JP2020129578A - Semiconductor laser light source device - Google Patents

Abstract

To provide a semiconductor laser light source device that uses a plurality of semiconductor laser chips to increase optical output while suppressing enlargement of a device scale.SOLUTION: A semiconductor laser light source device includes a plurality of semiconductor laser chips which are formed on an upper layer of a surface of a heat sink and have light emission regions respectively, and a refracting optical system that receives a bundle of light beams emitted from the light emission regions, changes a traveling direction, and emits light. At least two semiconductor laser chips are arranged to be inclined with respect to each other when viewed from a first direction orthogonal to the surface of the heat sink so that principle light beams of the bundle of light beams emitted from the respective light emission regions of the respective semiconductor laser chips are not parallel to each other, and the refractive optical system is configured by an optical system in which a first focus on a first plane formed by the first direction and an optical axis direction of the refractive optical system, and a second direction on a second plane formed by the optical axis direction and a second direction orthogonal to the optical axis direction are displaced with respect to the optical axis direction.SELECTED DRAWING: Figure 6

Description

The present invention relates to a semiconductor laser light source device, and more particularly to a semiconductor laser device having a plurality of semiconductor laser chips.

The use of semiconductor laser chips as light sources for projectors is being promoted. In recent years, the market is expected to use a light source device that further increases the light output while using the semiconductor laser chip as a light source.

In order to increase the light output on the light source side, a method of condensing light emitted from a plurality of semiconductor laser chips can be considered. However, the semiconductor laser chip has a certain width, and there is a limit to closely disposing them. In other words, simply arranging a plurality of semiconductor laser chips would increase the size of the light source device.

From this point of view, for example, as in Patent Document 1 below, a semiconductor laser chip group is arranged in a first region, another semiconductor laser chip group is arranged in a second region different from the first region, and There is a technique of combining light emitted from a group of semiconductor laser chips using a light combining means composed of a slit mirror. By such a method, compared with the case where a plurality of semiconductor laser chips are simply arranged in the same place, it is possible to increase the light intensity while reducing the arrangement area.

JP, 2017-215570, A

By the way, as a method of increasing the light intensity on the light source side, a method of using a light source module provided with a plurality of semiconductor laser chips is known. According to this structure, a plurality of regions for emitting laser light (light emission regions: hereinafter, may be referred to as “emitters”) are provided according to the number of semiconductor laser chips installed. The present inventor has studied the use of such a light source module to increase the light intensity, and found that the following problems exist.

FIG. 1A is a perspective view schematically showing the structure of a semiconductor laser chip having one emitter. Such a semiconductor laser chip is sometimes called a "single emitter type". It should be noted that FIG. 1A also schematically shows a light flux of light (laser light) emitted from the emitter. In the present specification, a bundle of rays emitted from a single emitter is referred to as a “ray bundle”, and a ray emitted from the center of the emitter is referred to as a “main ray”.

In the case of a so-called “edge emitting type” semiconductor laser chip 100 as shown in FIG. 1A, it is known that the light flux 101L emitted from the emitter 101 has an elliptic cone shape. In the present specification, of the two directions (X direction and Y direction) orthogonal to the optical axis (Z direction shown in FIG. 1A), the direction in which the divergence angle of the light bundle 101L is large (Y direction shown in FIG. 1A) is referred to as “ The direction in which the divergence angle of the light beam 101L is small (the X direction shown in FIG. 1A) is called the “fast axis direction”, and the “slow axis direction” is called. The “fast axis” may be called “Fast axis”, and similarly, the “slow axis” may be called “Slow axis”.

FIG. 1B is a diagram schematically showing the light beam bundle 101L when viewed from the X direction and when viewed from the Y direction. As shown in FIG. 1B, the divergence angle θ _y of the ray bundle 101L is large in the fast axis direction and the divergence angle θ _x of the ray bundle 101L is small in the slow axis direction.

Note that in FIG. 1B, only the light rays emitted from the upper end and the lower end of the emitter 101 are drawn, and such a drawing method is also applied to the following drawings. Further, in each of the following drawings, the divergence angle of the light ray bundle (light ray bundle 101L or the like) may be exaggerated from the actual one for convenience of description.

When a plurality of semiconductor laser chips 100 are arranged and the light (light flux 101L) emitted from each semiconductor laser chip 100 is condensed and used, from the viewpoint of suppressing the size of the optical member, each light flux 101L is collimated. After being converted into light, it is generally condensed by a lens. Specifically, a collimating lens (also referred to as a “collimation lens”) is arranged in the subsequent stage of the semiconductor laser chip 100 to reduce the divergence angle of each light beam bundle 101L.

FIG. 2A is a drawing schematically showing a light beam traveling in the YZ plane direction when the collimator lens 102 is arranged in the subsequent stage of the semiconductor laser chip 100.

According to FIG. 2A, after passing through the collimating lens 102, the light beam bundle 101L becomes a substantially parallel light beam bundle (hereinafter, referred to as “substantially parallel light beam bundle”) in the fast axis direction (Y direction). In the present specification, the “substantially parallel ray bundle” or “substantially parallel ray bundle” refers to a ray bundle having a divergence angle of less than 4°. It should be noted that in each of the drawings from FIG. 2A onward, the substantially parallel light flux may be illustrated as a perfect parallel light flux.

FIG. 2B is a diagram schematically showing a light flux that travels in the XZ plane direction when the collimator lens 102 is arranged in the subsequent stage of the semiconductor laser chip 100. According to FIG. 2B, after passing through the collimator lens 102, the bundle of rays 101L becomes a bundle of substantially parallel rays also in the slow axis direction (X direction).

FIG. 3A schematically shows the structure of a light source module including a plurality of semiconductor laser chips 100 shown in FIG. 1A. As shown in FIG. 3A, the light source module 120 includes a submount 121, and a plurality of semiconductor laser chips (100, 110) on the upper layer of the surface of the submount 121. When viewed from the Z direction (optical axis direction), for example, as shown in FIG. 3B, the emitters (101, 111) are arranged adjacent to each other. Note that, in FIG. 3A, the spacing in the X direction between the emitters (101, 111) is exaggerated for convenience of illustration.

FIG. 4 shows a bundle of light rays (101L, 111L) emitted from each of the emitters (101, 111) mounted on the light source module 120 shown in FIG. It is schematically illustrated in a case where it is viewed from above. It should be noted that, in FIG. 4, only the emitters (101, 111) are shown in the diagram viewed from the X direction due to space limitations.

As shown in FIGS. 3A and 3B, the semiconductor laser chips (100, 110) are arranged such that the faces of the emitters (101, 111) are arranged in the X direction. That is, since the emitters (101, 111) are formed at the same coordinate position in the Y direction, the ray bundles (101L, 111L) are completely overlapped when viewed from the X direction. On the other hand, since the emitters (101, 111) are formed at different coordinate positions in the X direction, the light fluxes (101L, 111L) are displayed in different positions when viewed from the Y direction.

The mode of the light flux in the case where the collimator lens 102 is arranged at the rear stage of the light source module 120 shown in FIG. 3A as in FIGS. 2A and 2B will be examined. As described above with reference to FIG. 4, the ray bundles (101L, 111L) completely overlap each other when viewed from the X direction. Therefore, in the fast axis direction (Y direction), after passing through the collimating lens 102, the light beam bundles (101L, 111L) become substantially parallel light beam bundles as in FIG. 2A.

FIG. 5 is a diagram schematically showing a light beam bundle traveling in the XZ plane direction when the collimator lens 102 is arranged in the rear stage of the light source module 120. Note that, due to space limitations, the size of each semiconductor laser chip (100, 110) included in the light source module 120 is shown in a partially reduced size.

As described above, the light source module 120 includes the plurality of semiconductor laser chips (100, 110), and the respective emitters (101, 111) are arranged so as to be separated in the X direction. Therefore, the X coordinate at the center position of the collimator lens 102 and the X coordinate at the center position of each emitter (101, 111) inevitably deviate.

As a result, each of the ray bundle 101L emitted from the emitter 101 and the ray bundle 111L emitted from the emitter 111 becomes a substantially parallel ray bundle after passing through the collimating lens 102, but the principal ray 101Lm of the ray bundle 101L, It is not parallel to the principal ray 111Lm of the ray bundle 111L. That is, the light bundle 101L and the light bundle 111L have different traveling directions in the X direction (traveling directions on the XZ plane).

In the case of such a configuration, for example, even if each of the light beam bundles (101L, 111L) is condensed by using the condensing optical system later, the light beam bundle group after the condensing spreads and is guided in the target direction. The light beam that cannot be generated will be generated. As a result, the utilization efficiency of light is reduced.

After passing through the collimating lens 102, the angles of the traveling directions of the light bundle 101L and the light bundle 111L on the XZ plane with respect to the optical axis (Z-axis) are between the emitters (101, 111) relative to the focal length of the collimating lens 102. It is determined by the relative value of the distance. More specifically, when the distance between the optical axis of the collimator lens 102 and the position of each emitter (101, 111) farthest from the optical axis of the collimator lens 102 is d, and the focal length f of the collimator lens 102 is f , The angle θ between the traveling direction of each principal ray (101Lm, 111Lm) of the light bundle (101L, 111L) and the optical axis of the collimator lens 102 is defined by θ=tan ⁻¹ (d/f). At this time, the angle θ _xm formed by the principal ray 101Lm and the principal ray 111Lm is twice the above θ.

As shown in FIG. 5, the principal ray 101L and the principal ray 111L travel through the collimator lens 102 so as to approach each other in the X direction, and thereafter, travel in a direction in which they depart from each other. As a result, in the mode of FIG. 5, the light bundle 101L and the light bundle 111L are completely separated at the position z1 in the optical axis direction (Z direction).

Conversely, when the distance between the emitters (101, 111) is sufficiently negligible with respect to the focal length of the collimator lens 102, the chief ray 101Lm of the ray bundle 110L also in the X direction. And the angle formed by the ray bundle 111L and the principal ray 111Lm substantially approaches 0°, and the ray bundles (101L, 111L) are not separated. However, for this purpose, the collimator lens 102 needs to be a lens having a sufficiently long focal length, and the size of the optical system is enlarged.

In particular, when a plurality of light source modules 120 are arranged to form a light source device, it is necessary to arrange the collimator lens 102 corresponding to the emitters (101, 111) included in each light source module 120. It gets bigger.

In view of the above problems, it is an object of the present invention to provide a semiconductor laser light source device that uses a plurality of semiconductor laser chips and that enhances the optical output while suppressing the expansion of the device scale.

The semiconductor laser light source device according to the present invention,
Heatsink,
A plurality of semiconductor laser chips formed on the upper surface of the surface of the heat sink and having a light emitting region;
A light flux emitted from the light emission region of the plurality of semiconductor laser chips is incident, and a refraction optical system that changes the traveling direction and emits is provided,
The at least two semiconductor laser chips are orthogonal to the surface of the heat sink so that the chief rays of the light flux emitted from the light emission regions of the respective semiconductor laser chips are not parallel to each other. When viewed from the direction, they are arranged at an angle to each other,
The refracting optical system is orthogonal to the optical axis direction and the first direction, which is a focus on a first plane formed by the first direction and the optical axis direction of the refracting optical system. A second focal point, which is a focal point on a second plane formed by the second direction, is composed of an optical system displaced in the optical axis direction.

As described above with reference to FIG. 5, in the semiconductor laser light source device including a plurality of semiconductor laser chips, the light emitting regions (emitters) are arranged apart from each other in the slow axis direction. As a result, the light beam spreads in the slow axis direction.

On the other hand, according to the above configuration, at least two semiconductor laser chips are arranged on the surface of the heat sink so as to be inclined with respect to each other. More specifically, the at least two semiconductor laser chips are arranged such that the principal rays of the bundle of rays emitted from the light emission region of each semiconductor laser chip are not parallel to each other.

First, for the sake of simplicity, two semiconductor lasers are arranged so that the principal rays of the bundle of rays emitted from the light emitting regions of the two semiconductor laser chips come closer to each other as they travel on the second plane. A case where the chips are arranged at an inclination will be described. This aspect is called the "first aspect". In the case of the first aspect, the distance between the light fluxes emitted from the respective light emission regions decreases as they travel on the second plane.

Here, in the refractive optical system included in the semiconductor laser light source device according to the present invention, the focal point on the first plane (first focal point) and the focal point on the second plane (second focal point) are displaced in the optical axis direction. It is composed of the optical system. For example, the position where the light emitting area exists in the optical axis direction is the first focal point, and the vicinity of the position where the chief rays of the light fluxes emitted from the respective light emitting areas intersect with each other in front of the first focal point. It can be the second focus. At this time, the bundle of rays emitted from the two light emitting regions and traveling on the second plane has a distance larger than that of the light emitting regions at the position of the second focal point of the refractive optical system. Becomes shorter. Since the divergence angle of the ray bundle after passing through the refracting optical system depends on the beam width of the ray bundle at the focus position, such a configuration suppresses the divergence angle of the ray bundle traveling on the second plane. The effect is obtained. As a result, the spread of the light flux is suppressed more than in the conventional case, so that it is possible to downsize the condensing optical system arranged in the subsequent stage while maintaining the light utilization efficiency.

The semiconductor laser chip may be arranged on the surface of the heat sink via a submount. In this case, one semiconductor laser chip may be mounted on one submount, or a plurality of semiconductor laser chips may be mounted.

More specifically,
When the distance in the second direction between the chief rays emitted from the light emitting regions of the adjacent semiconductor laser chips is d1,
The plurality of semiconductor laser chips, in the optical axis direction, from the light emitting region to a specific position on the light emitting region side with respect to the refractive optical system, as the semiconductor laser chips progress in the optical axis direction. It may be arranged so as to be inclined with respect to each other so that the distance d1 becomes small.

At this time, the second focus may be located closer to the refractive optical system than the first focus in the optical axis direction.

Contrary to the above-described configuration, the chief rays of the bundle of rays emitted from the light emitting regions of the two semiconductor laser chips are separated from each other as they travel on the second plane. The two semiconductor laser chips may be arranged to be inclined. This aspect is called the "second aspect". In this case, the separation distance of the light flux emitted from each light emission region widens as it travels on the second plane.

However, even with such a configuration, when the principal rays of the bundle of rays emitted from the respective light emission regions are virtually extended in the direction opposite to the traveling direction, these virtual principal rays intersect each other. The same effect as described above can be obtained by setting the vicinity of the position where the light is emitted as the second focus and setting the position where the light emitting region exists in the optical axis direction as the first focus. That is, even in the case of this configuration, the bundle of rays emitted from the two light emitting areas and traveling on the second plane is compared with the distance between the light emitting areas and the second focal point of the refractive optical system. The separation distance at this position (corresponding to the separation distance of the virtual ray bundle here) becomes shorter. As described above, since the divergence angle of the ray bundle after passing through the refractive optical system depends on the beam width of the ray bundle at the focal point, even in the case of this second aspect, the same as in the first aspect. In addition, the effect of suppressing the divergence angle of the light beam traveling on the second plane can be obtained.

More specifically, virtual principal rays obtained by virtually extending the chief rays emitted from the light emitting regions of the adjacent semiconductor laser chips in a direction opposite to the refractive optical system. If the distance in the second direction is d1,
The plurality of semiconductor laser chips, in the optical axis direction, in a direction opposite to the optical axis direction from a virtual light emitting area corresponding to an end surface at a position opposite to the light emitting area to a specific position. The distance d1 may be smaller than the distance d1.

At this time, the second focus may be located on the side farther from the refractive optical system in the optical axis direction than the first focus.

The refracting optical system has any specific configuration as long as the first focus and the second focus are optical systems displaced in the optical axis direction.

As an example,
The refracting optical system may be configured by a single lens having a different focal length in the first direction and a different focal length in the second direction. An anamorphic lens or the like can be used as such a lens.

As another example,
The refraction optical system,
With respect to the light flux emitted from the light emission region, a divergence angle in the first direction is reduced, and a first lens having the first focus as a focus,
A second lens having a second focus as a focal point, which is disposed in the latter stage of the first lens and reduces the divergence angle in the second direction with respect to the light flux emitted from the light emission region. You may have it.

The first lens may be a FAC (Fast Axis Collimation) lens, and the second lens may be a SAC (Slow Axis Collimation) lens.

As another example,
The refraction optical system,
With respect to the light flux emitted from the light emission region, reducing the divergence angle in the first direction and the second direction, a first lens having the first focus as a focus,
A second lens having a second focus as a focal point, which is disposed in the latter stage of the first lens and reduces the divergence angle in the second direction with respect to the light flux emitted from the light emission region. You may have it.

In this case, the first lens may be a collimator lens that collimates in both the fast axis and the slow axis, and the second lens may be a cylindrical lens that refracts only in the slow axis direction.

The plurality of semiconductor laser chips may be connected in series. In particular, the semiconductor laser device includes a semiconductor laser chip according to the present invention (hereinafter, referred to as “first semiconductor laser chip”) and a semiconductor laser having a higher driving voltage than that and emitting light in another wavelength band. In the case of including a chip (hereinafter, referred to as “second semiconductor laser chip”), it is useful in that the driving power source for the first semiconductor laser chip and the second semiconductor laser chip can be shared.

According to the present invention, by using a plurality of semiconductor laser chips, a semiconductor laser light source device in which the optical output is increased while suppressing the expansion of the device scale is realized.

It is a perspective view which shows the structure of a semiconductor laser chip typically. 1A and 1B are schematic illustrations of a light beam emitted from the semiconductor laser chip of FIG. 1A, divided into a case viewed from an X direction and a case viewed from a Y direction. It is the drawing which showed typically the light flux which advances in a YZ plane direction, when a collimating lens is arranged at the latter part of a semiconductor laser chip. It is the drawing which showed typically the light flux which advances in a XZ plane direction, when a collimating lens is arranged at the latter part of a semiconductor laser chip. It is a perspective view which shows typically the structure of the light source module provided with several semiconductor laser chips. FIG. 3B is a schematic view of an emitter included in the light source module of FIG. 3A when viewed from the optical axis direction. FIG. 3B is a schematic diagram showing a bundle of rays emitted from the light source module of FIG. 3A, divided into a case viewed from the X direction and a case viewed from the Y direction. FIG. 3B is a diagram schematically showing a bundle of rays that travels in the XZ plane direction when a collimator lens is arranged in the latter stage of the light source module of FIG. 3A. It is drawing which shows typically the structure of 1st embodiment of a semiconductor laser light source device. It is drawing which shows typically the structure of the semiconductor laser chip with which a semiconductor laser light source device is equipped. FIG. 7 is a partially enlarged view of the XZ plan view shown in the lower part of FIG. 6. 7 is a graph showing the light intensity distribution by angle in the slow axis direction and the fast axis direction of the bundle of rays after exiting the collimator lens in the semiconductor laser light source device of Comparative Example 1. 7 is a graph showing the light intensity distribution by angle in the slow axis direction and the fast axis direction of the bundle of rays after exiting the collimator lens in the semiconductor laser light source device of Comparative Example 2. 7 is a graph showing the light intensity distribution by angle in the slow axis direction and the fast axis direction of the bundle of rays of light after exiting the lens in the semiconductor laser light source device of Example 1. 7 is a graph showing the light intensity distribution by angle in the slow axis direction and the fast axis direction indicated by the bundle of rays of light after exiting the lens in the semiconductor laser light source device of Example 2. 16 is a graph showing the light intensity distribution by angle in the slow axis direction and the fast axis direction of the bundle of rays of light after exiting the lens in the semiconductor laser light source device of Example 3. 16 is a graph showing the light intensity distribution by angle in the slow axis direction and the fast axis direction of the bundle of rays of light after exiting the lens in the semiconductor laser light source device of Example 4. 19 is a graph showing the light intensity distribution by angle in the slow axis direction and the fast axis direction of the bundle of rays of light after exiting the lens in the semiconductor laser light source device of Example 5. 16 is a graph showing the light intensity distribution by angle in the slow axis direction and the fast axis direction of the bundle of rays of light after exiting the lens in the semiconductor laser light source device of Example 6. 16 is a graph showing the light intensity distribution by angle in the slow axis direction and the fast axis direction of the bundle of rays of light after exiting the lens in the semiconductor laser light source device of Example 7. 7 is a graph showing light intensity distributions by angle in the slow axis direction and the fast axis direction, which are shown by the bundle of light rays after exiting the lens, in the semiconductor laser light source devices of Examples 1 to 7 and Comparative Example 2. It is drawing which shows typically the structure of 2nd embodiment of a semiconductor laser light source device. It is drawing which shows typically the structure of 3rd embodiment of a semiconductor laser light source device. It is drawing which shows typically the structure of another embodiment of a semiconductor laser light source device.

Each embodiment of the semiconductor laser light source device according to the present invention will be described with reference to the drawings as appropriate. It should be noted that each of the following drawings is a schematic illustration, and the actual dimensional ratio and the dimensional ratio in the drawings do not necessarily match. In addition, the dimensional ratios do not always match between the drawings.

[First embodiment]
A first embodiment of a semiconductor laser light source device according to the present invention will be described.

FIG. 6 is a drawing schematically showing the configuration of the first embodiment of the semiconductor laser light source device. Further, FIG. 7 is a drawing schematically showing a configuration of a semiconductor laser chip included in the semiconductor laser light source device.

The semiconductor laser light source device 1 includes a semiconductor laser chip (10, 20) and a refracting optical system 30. As shown in FIG. 7, each semiconductor laser chip (10, 20) is formed on the same heat sink 5, and is housed in the casing member 6. Then, by being supplied with power from the external leads 4, the light flux (12, 22) is emitted from the light emission regions (11, 21) of each semiconductor laser chip (10, 20). The bundle of rays (12, 22) is extracted to the outside through, for example, the window member 7 provided in the casing member 6. In this embodiment, the semiconductor laser chip 10 and the semiconductor laser chip 20 are connected in series with each other.

Note that, in the following, description will be given with reference to the XYZ coordinate system illustrated in FIGS. That is, the direction of the optical axis 30A of the refractive optical system 30 is defined as the "Z direction". Further, the fast axis direction of the light flux (12, 22) emitted from each light emission region (11, 21) is defined as "Y direction", and the slow axis direction is defined as "X direction". At this time, the Y direction corresponds to the “first direction” and the X direction corresponds to the “second direction”. The YZ plane defined by the Y direction and the Z direction corresponds to the “first plane”, and the XZ plane defined by the X direction and the Z direction corresponds to the “second plane”. 6 and 7, the configuration on the YZ plane and the configuration on the XZ plane are shown separately in the upper and lower stages. Since the upper part of FIG. 7 shows the state when the casing member 6 is viewed from the X direction, the two external leads 4 shown in the lower part of FIG. 7 are overlapped and displayed in the X direction. Has been done.

Further, in the following, when simply described as “X direction”, “Y direction”, or “Z direction”, the positive and negative directions are not distinguished. On the other hand, when the positive and negative directions are separately described, they are described as “+X direction”, “−X direction”, and the like.

As shown in FIG. 7, the semiconductor laser chip (10, 20) is formed on the surface of the heat sink 5. Here, the case where the surface of the heat sink 5 is parallel to the XZ plane is illustrated. The semiconductor laser chip 10 and the semiconductor laser chip 20 are arranged so as to be separated in the X direction.

Although not shown in FIG. 7, the semiconductor laser chip (10, 20) may be mounted on the surface of the heat sink 5 via a submount. The heat sink 5 is provided for the purpose of discharging heat generated when the semiconductor laser chip (10, 20) emits light, and is made of a material having high thermal conductivity such as copper or copper alloy. The submount is provided with electrode wiring (not shown) on its surface, for example, to form an electrical connection for power supply to the semiconductor laser chip (10, 20) and also to connect the semiconductor laser chip (10, 20). It also has a function of guiding the heat generated during light emission to the heat sink 5 side. The material of the submount is appropriately selected in consideration of heat dissipation, insulation, difference in linear expansion coefficient with the semiconductor laser chip (10, 20), and the like. As an example, the submount is made of a material such as AlN, Al ₂ O ₃ , SiC, and CuW.

Further, as shown in the lower part of FIG. 7, the semiconductor laser chips (10, 20) are arranged so as to be inclined with respect to each other when viewed from the Y direction. Regarding this point, returning to FIG. 6, the description will be continued.

In FIG. 6, the upper diagram schematically shows how the light beam bundles (12, 22) emitted from the light emission regions (11, 21) of the semiconductor laser chip (10, 20) travel along the YZ plane. It is a drawing shown typically. Further, the lower diagram of FIG. 6 is a diagram schematically showing how the light flux (12, 22) travels along the XZ plane. That is, in FIG. 6, the upper part of the drawing corresponds to the fast axis direction of the light emitting regions (11, 21) in the upper direction of the drawing, and the lower part of the drawing illustrates the upper part of the drawing in the slow direction of the light emitting regions (11, 21). Corresponds to the axial direction.

In FIG. 6, the principal rays (12 m, 22 m) of the light bundle (12, 22) are shown by a chain line for convenience. The same applies to the following drawings.

As described above, the semiconductor laser chip (10, 20) emits the elliptical cone-shaped light beam bundle (12, 22) from the light emitting region (11, 21). As described above with reference to FIG. 4, since the respective light emitting regions (11, 21) are formed at the same coordinate position in the Y direction, each light flux (12 , 22) completely overlap (see the upper part of FIG. 6). Further, as described above, since the semiconductor laser chips (10, 20) are arranged apart from each other in the X direction, the light emitting regions (11, 21) are formed at different coordinate positions in the X direction. It Therefore, when viewed from the Y direction, the light beam bundles (12, 22) are displayed with their respective positions displaced (see the lower part of FIG. 6).

Here, the refraction optical system 30 included in the semiconductor laser light source device 1 of the present embodiment includes a lens 31 having a different focal length on the YZ plane and a focal length on the XZ plane. As such a lens 31, for example, an anamorphic lens or the like can be used.

More specifically, the lens 31 has a focal length in the Z direction between the focus 30yf on the YZ plane and the center position of the lens 31, and a focal length in the Z direction between the focus 30xf on the XZ plane and the center position of the lens 31. Different from the distance. The focus 30yf corresponds to the "first focus", and the focus 30xf corresponds to the "second focus". At this time, the focal point 30yf and the focal point 30xf are displaced in the Z direction. In the configuration of this embodiment, the focal point 30xf is located closer to the lens 31 than the focal point 30yf in the Z direction by the distance dz.

The lens 31 has a function similar to that of the collimator lens 102 described above with reference to FIG. 2A for the bundle of rays (12, 22) traveling on the YZ plane. For the same reason as described above with reference to FIG. 4, the light flux (12, 22) emitted from the semiconductor laser chip (10, 20) travels with a large divergence angle θ _y in the fast axis direction. To do. That is, if the lens 31 does not exist, the bundle of rays (12, 22) travels on the YZ plane while expanding in the Y direction. The lens 31 is provided for the purpose of suppressing the spread of the light beam bundle (12, 22) in the Y direction. More preferably, the lens 31 converts a bundle of rays (12, 22) traveling in the Z direction on the YZ plane into a bundle of substantially parallel rays (13, 23). Therefore, the lens 31 is arranged so that the focal point 30yf on the YZ plane is near the position of the light emitting region (11, 21) of the semiconductor laser chip (10, 20).

The “near the position of the light emitting area (11, 21)” here means that the Z coordinate is completely the same as the Z coordinate of the light emitting area (11, 21) (hereinafter, referred to as “coordinate Z0” for convenience). When the distance Z between the coordinate Z0 and the Z coordinate of the lens 31 in the Z direction is zc, the distance in the Z direction is within 10% of the distance Zc with respect to the coordinate Z0. Including the area displaced to the front and back.

On the other hand, as described above, the semiconductor laser chips (10, 20) are arranged in a mutually inclined state on the XZ plane. In the case of the present embodiment, the principal ray 12m of the light beam bundle 12 emitted from the light emission area 11 of the semiconductor laser chip 10 and the main ray bundle 22 of the light beam bundle 22 emitted from the light emission area 21 of the semiconductor laser chip 20. The semiconductor laser chips (10, 20) are arranged so as to gradually approach the light beam 22m in the X direction as it travels in the Z direction.

More specifically, as shown in an enlarged view in FIG. 8, the semiconductor laser chip 10 has a state in which the end face of the light emitting region 11 is arranged in parallel with the X direction, and then the angle θ ₁₁ in the clockwise direction on the XZ plane. It is placed in a rotated state. On the other hand, the semiconductor laser chip 20 is arranged in a state in which the end face of the light emitting region 21 is arranged in parallel with the X direction and is rotated counterclockwise by an angle θ ₁₂ on the XZ plane. For convenience of illustration, in FIG. 8, unlike FIG. 6, only the chief ray (12 m, 22 m) is representatively shown for the ray bundle (12, 22 ).

Since the light emitting region 11 and the light emitting region 21 are separated from each other by the distance d0 in the X direction on the end face, each chief ray (12 m, 22 m) is also separated from the end face by the distance d0 in the XZ plane. Go on top. However, as described above, since the semiconductor laser chips (10, 20) are arranged so as to be inclined with respect to each other, the chief ray 12m and the chief ray 22m are closer to each other with the distance d1 in the X direction being closer to XZ. Proceed on a plane. This means that the light beam bundle 12 emitted from the light emission region 11 and the light beam bundle 22 emitted from the light emission region 21 travel on the XZ plane while approaching each other in the X direction (Fig. (See the lower part of 6.)

At this time, as schematically shown in FIG. 8, at a specific position 40, the principal ray 12m and the principal ray 22m intersect on the XZ plane. The specific position 40 corresponds to the position where the light bundle 12 and the light bundle 22 are closest to each other in the X direction. Therefore, by setting the focal point 30xf of the lens 31 on the XZ plane near this specific position 40, the light beam bundle (12, 22) incident on the lens 31 has a beam diameter of the beam diameter existing near the specific position 40. It can be regarded as a bundle of rays emitted from a small virtual light source. As a result, the lens 31 can convert the bundle of rays (12, 22) traveling on the XZ plane into a bundle of substantially parallel rays (13, 23).

The term "near the specific position 40" as used herein means that the Z coordinate is completely coincident with the Z coordinate of the specific position 40 (hereinafter referred to as "coordinate Z40" for convenience), and the light emitting region (11). , 21) of the Z coordinate (corresponding to the above-mentioned “coordinate Z1”) and the coordinate Z40 in the Z direction is defined as za, the Z direction is a length within 25% of the displacement za with respect to the coordinate Z40. Including the area displaced to the front and back.

Note that the focal point 30xf of the lens 31 on the XZ plane is preferably near the position of the specific position 40, but the interval d1 of the bundle of rays (12, 22) in the X direction is the light emission region (11, 21). If the position is shorter than the interval d0 of, the position may be apart from the vicinity of the position of the specific position 40 in the Z direction.

[Verification]
According to the semiconductor laser light source device 1 of the present embodiment, the spread of the bundle of rays (13, 23) after exiting the lens 31 in the slow axis direction (X direction) is suppressed, based on the simulation result. explain. The simulation conditions are as follows.

(Comparative Example 1)
As shown in FIG. 5, the semiconductor laser chip (100, 110) in which the respective light emission regions (101, 111) are arranged in parallel on the XZ plane, and the focal length Ff in the fast axis direction and the slow axis direction. The semiconductor laser light source device including the collimator lens 102 having the same focal length Fs (4 mm) was used as the configuration of Comparative Example 1.

The length of the distance d0 in the X direction between the center position of the light emitting region 101 and the center position of the light emitting region 111 was set to 112.5 μm. Further, the shape of the light emitting area 101 and the light emitting area 111 on the XY plane is a rectangular shape having a length in the X direction of 75 μm and a length in the Y direction of 1 μm.

Further, the divergence angle of the light beam bundles (101L, 111L) emitted from the light emission regions (101, 111) in the fast axis direction (Y direction) is 33°, and the divergence angle in the slow axis direction (X direction). Was 12°.

(Comparative example 2)
The angle θ ₁₁ and the angle θ ₁₂ shown in FIG. 8 are both 15°, and the semiconductor laser chips (10, 20) are arranged such that the light emitting regions (11, 21) are inclined at 30° to each other on the XZ plane. The semiconductor laser light source device including the collimator lens 102 having the same focal length Ff in the fast axis direction and the focal length Fs in the slow axis direction (4 mm) is configured as Comparative Example 2. The length of the distance d0 in the X direction between the center position of the light emitting region 11 and the center position of the light emitting region 21, and the shapes of the light emitting region 11 and the light emitting region 21 on the XY plane are the same as those of Comparative Example 1. did. Further, the divergence angles in the fast axis direction and the slow axis direction of the light beam bundles (12, 22) emitted from the respective light emission regions (11, 21) are the same as the light beam bundles (101L, 111L) in Comparative Example 1. did.

(Example 1)
The angle θ ₁₁ and the angle θ ₁₂ shown in FIG. 8 are both 15°, and the semiconductor laser chips (10, 20) are arranged such that the light emitting regions (11, 21) are inclined at 30° to each other on the XZ plane. And a lens 31 having a focal length Ff in the fast axis direction of 4 mm and a focal length Fs in the slow axis direction of 3.9 mm, the semiconductor laser light source device 1 has the configuration of the first embodiment. As for the length of the distance d0 in the X direction between the center position of the light emitting area 11 and the center position of the light emitting area 21 and the shapes of the light emitting area 11 and the light emitting area 21 on the XY plane, Comparative Example 1 And 2 were common. Further, the divergence angles of the light beam bundles (12, 22) emitted from the respective light emission regions (11, 21) in the fast axis direction and the slow axis direction were also common to Comparative Example 1.

(Examples 2 to 7)
It is common to the first embodiment except that the focal length Fs in the slow axis direction is different. Specifically, it is as follows.
Example 2 The focal length Ff of the lens 31 in the fast axis direction was set to 4 mm, and the focal length Fs of the lens 31 in the slow axis direction was set to 3.8 mm.
Example 3 The focal length Ff of the lens 31 in the fast axis direction was set to 4 mm, and the focal length Fs of the lens 31 in the slow axis direction was set to 3.7 mm.
Example 4 The focal length Ff of the lens 31 in the fast axis direction was set to 4 mm, and the focal length Fs of the lens 31 in the slow axis direction was set to 3.6 mm.
Example 5: The focal length Ff of the lens 31 in the fast axis direction was set to 4 mm, and the focal length Fs of the lens 31 in the slow axis direction was set to 3.5 mm.
Example 6 The focal length Ff of the lens 31 in the fast axis direction was set to 4 mm, and the focal length Fs of the lens 31 in the slow axis direction was set to 3.4 mm.
Example 7: The focal length Ff of the lens 31 in the fast axis direction was 4 mm, and the focal length Fs of the lens 31 in the slow axis direction was 3.3 mm.

In each of the semiconductor laser light source devices of Comparative Examples 1 and 2 and Examples 1 to 7, the light intensity for each angle of the bundle of light beams emitted from the collimator lens 102 or the lens 31 is set to the fast axis direction (Y direction) and the slow axis direction. It was calculated by simulation in each of the axial directions (X direction). The results are shown in FIGS. 9A to 9I. In each figure, the horizontal axis is the angle and the vertical axis is the relative value of the light intensity. In each figure, "fast" corresponds to the divergence angle in the fast axis direction (Y direction), and "slow" corresponds to the divergence angle in the slow axis direction (X direction).

FIG. 9J is a graph in which the results of Comparative Example 2 and Examples 1 to 7 are plotted and summarized. In FIG. 9J, the horizontal axis is the focal length Fs in the slow axis direction of the lens 31, and the vertical axis is the value of the half width at half maximum (HWHM) of the angular intensity distribution of the bundle of rays in the slow axis direction. Is. In FIG. 9J, for comparison, the half width at half maximum in Comparative Example 1 is also indicated by a broken line parallel to the horizontal axis. Other plots correspond to Examples 1 to 7 in order from the right side of the horizontal axis Fs, that is, when Fs is 3.9 mm to 3.3 mm.

As shown in FIG. 9A, in the case of the semiconductor laser light source device of the conventional configuration (Comparative Example 1), the bundle of rays after being emitted from the collimator lens 102 is separated as two bundles of rays in the slow axis direction. I understand. Then, according to the region where the light intensity shows a half value (full width at half maximum), it can be seen that the two ray bundle groups have a divergence angle of about 4.4° in the slow axis direction. The half width at half maximum (HWHM) value at this time is about 2.2°.

As shown in FIG. 9B, in the case of Comparative Example 2 including the semiconductor laser chips (100, 110) of Comparative Example 1 instead of the semiconductor laser chips (100, 110) tilted on the XZ plane, As with Comparative Example 1, it can be seen that the bundle of rays after exiting the collimator lens 102 is separated as two bundles of rays in the slow axis direction. The divergence angle of this ray bundle group in the slow axis direction is about 4.7°, which is larger than that in Comparative Example 1. The full width at half maximum (HWHM) value at this time is about 2.4°.

As shown in FIG. 9C, a lens 31 having a focal length Fs in the slow axis direction of 3.9 mm, which is shorter than the focal length Ff (4.0 mm) in the fast axis direction, is provided instead of the collimator lens 102 of Comparative Example 2. In the case of Example 1 as well, similar to Comparative Example 1 and Comparative Example 2, the ray bundle group after exiting the lens 31 is separated as two ray bundles (13, 23) in the slow axis direction. I understand. However, according to the region where the light intensity shows a half value (full width at half maximum), it can be seen that in Example 1, the two ray bundle groups have a divergence angle of about 4.2° in the slow axis direction. This result shows that the divergence angle in the slow axis direction can be suppressed in Example 1 as compared with Comparative Examples 1 and 2. The full width at half maximum (HWHM) value at this time is about 2.1°.

As shown in FIGS. 9D to 9G, when the focal length Fs in the slow axis direction is made shorter than that in the first embodiment (Examples 2 to 5), the half-width of the intensity distribution in the slow axis direction is accompanied by this. It can be seen that is further reduced. This shows that the divergence angle in the slow axis direction of the bundle of rays after exiting the lens 31 can be further suppressed. According to the results of Examples 3 to 5, it can be seen that the bundles of light rays after exiting the lens 31 overlap with each other in the slow axis direction.

It is confirmed that when the focal length Fs in the slow axis direction is further reduced from that in Example 5 (Examples 6 and 7), the full width at half maximum of the intensity distribution in the slow axis direction tends to increase (FIG. 9H-. See FIG. 9J). However, in Example 6, the full width at half maximum of the light intensity in the slow axis direction is about 2.0° (half width at half maximum is about 1.0°), and in Example 7, the full width at half maximum in the slow axis direction is about 3.2°. (Half width at half maximum is about 1.6°). That is, also in Examples 6 and 7, the half value width of the light intensity in the slow axis direction was smaller than that in Comparative Examples 1 and 2, and the divergence angle of the ray bundle group in the slow axis direction was suppressed. I understand that.

As shown in FIG. 8, the states of Examples 6 and 7 are in the Z direction (direction of the optical axis 30A) rather than the specific position 40 at which the chief ray 12m and the chief ray 22m intersect on the XZ plane. ) Means that the focal point 30xf of the lens 31 on the XZ plane is located at a position close to the lens 31. That is, at this position, the distance d1 between the principal rays (12 m, 22 m) is wider than the specific position 40, but is closer than the distance d0 at the end faces of the light emitting regions (11, 21). Therefore, it can be concluded that the spread of the ray bundles (13, 23) in the slow axis direction (X direction) is suppressed more than in Comparative Example 1.

[Second embodiment]
The second embodiment of the semiconductor laser light source device according to the present invention will be described focusing on the points different from the first embodiment.

As described above in the first embodiment, the refractive optical system 30 is an optical system in which the focal length on the YZ plane and the focal length on the XZ plane are different. In the first embodiment, the refracting optical system 30 is composed of one lens 31, but in the present embodiment, the refracting optical system 30 is composed of a plurality of lenses. Note that other configurations are common to the first embodiment.

More specifically, as shown in FIG. 10, in the semiconductor laser light source device 1 of this embodiment, the refractive optical system 30 includes a first lens 32 and a second lens 33.

The first lens 32 has only the function of suppressing the divergence in the Y direction (fast axis direction) with respect to the light flux (12, 22) traveling in the Z direction, and moves in the X direction (slow axis direction). It is a lens that does not have a function of suppressing diffusion, and is sometimes called a FAC (Fast Axis Collimation) lens. On the other hand, the second lens 33 has only the function of suppressing the diffusion of the light flux (12, 22) traveling in the Z direction in the X direction (slow axis direction), and the Y direction (fast axis direction). It is a lens that does not have a function of suppressing the diffusion of light into the air, and is sometimes called by a name of SAC (Slow Axis Collimation) lens.

Similar to the lens 31 of the first embodiment, the first lens 32 has a focal point 30yf on the YZ plane near the position of the light emitting region (11, 21) of the semiconductor laser chip (10, 20). Will be placed. Further, the second lens 33 is arranged such that the focal point 30xf on the XZ plane is near the specific position 40 where the chief ray 12m and the chief ray 22m intersect, like the lens 31 of the first embodiment. ..

The first lens 32 has a function similar to that of the lens 31 described in the first embodiment with respect to the bundle of rays (12, 22) traveling on the YZ plane. On the other hand, the second lens 33 does not have a function of refracting the light ray bundle (12, 22) traveling on the YZ plane, and allows the incident light ray bundle to pass through as it is. As a result, as shown in the upper part of FIG. 10, the light beam bundles (12, 22) emitted from the respective light emission regions (11, 21) and traveling on the YZ plane are the first lens 32 and the second lens 33. After passing through, the light beam is converted into a substantially parallel ray bundle (13, 23) as in the first embodiment.

The first lens 32 does not have a function of refracting the ray bundle (12, 22) traveling on the XZ plane, and allows the incident ray bundle to pass through as it is. On the other hand, the second lens 33 has the same function as the lens 31 described in the first embodiment with respect to the bundle of rays (12, 22) traveling on the XZ plane. As a result, as shown in the lower part of FIG. 10, the ray bundles (12, 22) emitted from the respective light emission areas (11, 21) and traveling on the XZ plane pass through the first lens 32 as they are. When the light enters the second lens 33, it is refracted. Here, as in the first embodiment, the second lens 33 is arranged such that the focal point 30xf on the XZ plane is in the vicinity of the specific position 40 where the chief ray 12m and the chief ray 22m intersect, The principal ray (13m, 23m) of the bundle of rays (13, 23) after passing through the second lens 33 becomes substantially parallel on the XZ plane. As a result, similarly to the first embodiment, the bundle of rays (13, 23) after passing through the second lens 33 becomes a bundle of substantially parallel rays on the XZ plane.

Therefore, also in the semiconductor laser light source device 1 of the present embodiment, for the same reason as in the first embodiment, it is possible to obtain the light flux (13, 23) in which the divergence angle in the slow axis direction (X direction) is suppressed. it can.

[Third embodiment]
The second embodiment of the semiconductor laser light source device according to the present invention will be described focusing on the points different from the first embodiment.

As described above in the first embodiment, the refractive optical system 30 is an optical system in which the focal length on the YZ plane and the focal length on the XZ plane are different. In the first embodiment, the refracting optical system 30 is composed of one lens 31, but in the present embodiment, the refracting optical system 30 is composed of a plurality of lenses, as in the second embodiment. Is different. Note that other configurations are common to the first embodiment.

More specifically, as shown in FIG. 11, in the semiconductor laser light source device 1 of this embodiment, the refractive optical system 30 includes a first lens 34 and a second lens 35.

The first lens 34 is similar to the collimating lens 102 described above with reference to FIGS. 2A and 2B, with respect to the bundle of rays (12, 22) traveling in the Z direction, the Y direction (fast axis direction) and the X direction (fast axis direction). This is a lens showing a function of suppressing diffusion in the slow axis direction. The second lens 35 has only the function of suppressing the diffusion of the light flux (12, 22) traveling in the Z direction in the X direction (slow axis direction), and the Y direction (fast axis direction). It is a lens that does not have the function of suppressing the diffusion of light into the lens and is composed of a cylindrical lens. The SAC lens described above in the second embodiment can be used.

Like the lens 31 of the first embodiment, the first lens 34 has a focal point 30yf on the YZ plane near the position of the light emitting region (11, 21) of the semiconductor laser chip (10, 20). Will be placed. Since the first lens 34 is an ordinary collimating lens, the focal length in the Y direction and the focal length in the X direction are the same. Therefore, although not shown, the first lens 34 also has a focal point on the XZ plane in the vicinity of the position of the light emitting region (11, 21) of the semiconductor laser chip (10, 20).

On the other hand, the second lens 35 has a function of displacing the focal point of the first lens 34 on the XZ plane in the Z direction by making the focal point on the XZ plane different from that of the first lens 34. That is, in the second lens 35, the focal point 30xf on the XZ plane of the synthetic optical system (refractive optical system 30) with the first lens 34 is in the vicinity of the specific position 40 where the principal ray 12m and the principal ray 22m intersect. The focus is adjusted so that

The first lens 34 has the same function as the lens 31 described in the first embodiment with respect to the bundle of rays (12, 22) traveling on the YZ plane. On the other hand, the second lens 33 does not have a function of refracting the light ray bundle (12, 22) traveling on the YZ plane, and allows the incident light ray bundle to pass through as it is. As a result, as shown in the upper part of FIG. 11, the light beam bundles (12, 22) emitted from the respective light emission regions (11, 21) and traveling on the YZ plane are the first lens 32 and the second lens 33. After passing through, the light beam is converted into a substantially parallel ray bundle (13, 23) as in the first embodiment.

The first lens 34 also has a function of refracting the bundle of rays (12, 22) traveling on the XZ plane. Therefore, the ray bundle (12, 22) travels on the XZ plane, passes through the first lens 34, is refracted, and then enters the second lens 35. Here, as described above, the second lens 35 is installed in the synthetic optical system with the first lens 34 so that the focal point 30xf on the XZ plane is near the specific position 40. Therefore, when the ray bundle (12, 22) travels on the XZ plane and passes through the second lens 35, it is converted into a substantially parallel ray bundle (13, 23) for the same reason as in the first embodiment. ..

Therefore, also in the semiconductor laser light source device 1 of this embodiment, for the same reason as in the first embodiment, it is possible to obtain the light beam bundle (13, 23) in which the divergence angle in the slow axis direction (X direction) is suppressed. it can.

[Another embodiment]
Hereinafter, another embodiment will be described.

<1> In the above embodiment, the principal ray 12m of the light beam bundle 12 emitted from the light emission area 11 of the semiconductor laser chip 10 and the principal ray bundle 22 of the light beam bundle 22 emitted from the light emission area 21 of the semiconductor laser chip 20. The case where the semiconductor laser chips (10, 20) are arranged so as to be inclined so that the light beam 22m gradually approaches the X direction as it travels in the Z direction has been described. However, as shown in FIG. 12, the semiconductor laser chip (10, 20) is tilted so that the principal ray 12m and the principal ray 22m are separated in the X direction (slow axis direction) as they travel in the Z direction. It does not matter even if it is arranged as.

In the case of this configuration, when each principal ray (12 m, 22 m) is virtually extended to the opposite side (−Z direction) to the light emitting area (11, 21), the light emitting area (11, 21) is There is a position where the principal rays (12 ma, 22 ma) of the bundle of rays virtually emitted from the opposite end faces (11 a, 12 a) intersect. The intersecting position may be the specific position 40, and the focus 30xf on the XZ plane of the lens 31 may be located near the specific position 40.

Even with such a configuration, as in the first embodiment, the bundle of rays (12, 22) that travels on the XZ plane and is incident on the lens 31 is as if the beam diameter existing near the specific position 40 is small. It can be regarded as a light flux emitted from the light source. As a result, the lens 31 can convert the bundle of rays (12, 22) traveling on the XZ plane into a bundle of substantially parallel rays (13, 23).

Note that FIG. 12 illustrates the case where the refractive optical system 30 is configured by the lens 31 described above in the first embodiment, but it is also possible to adopt the configurations of the second embodiment and the third embodiment. is there.

<2> In the second embodiment and the third embodiment, the case where the refractive optical system 30 has two lenses has been described. However, the present invention does not exclude the case where the refractive optical system 30 has three or more lenses.

<3> In each of the above embodiments, the two semiconductor laser chips (10, 20) mounted on the same heat sink 5 are connected in series and are fed with power through the external leads 4. did. However, the present invention does not exclude the case where two semiconductor laser chips (10, 20) mounted on the same heat sink 5 are connected in parallel with each other.

<4> In each of the above embodiments, the semiconductor laser light source device 1 has been described by exemplifying the case where two semiconductor laser chips (10, 20) are mounted on the same heat sink 5. However, the semiconductor laser light source device 1 according to the present invention may include three or more semiconductor laser chips on the same heat sink 5. In this case, it suffices that the chief rays emitted from the light emitting areas of at least two semiconductor laser chips are arranged so as not to be parallel to each other, and the chief rays emitted from two adjacent light emitting areas are adjacent to each other. Are preferably non-parallel. Furthermore, it is particularly preferable that the chief rays emitted from all the adjacent light emission regions are arranged so as not to be parallel to each other.

<5> In each of the above embodiments, the case where each semiconductor laser chip (10, 20) includes one light emitting region (11, 21) has been described. However, each semiconductor laser chip (10, 20) may be configured to have a plurality of light emission regions (multi-emitter type).

<6> The refracting optical system 30 described in each embodiment may be housed inside the casing member 6, may also serve as the window member 7, or may be arranged outside the casing member 6. It doesn't matter.

1: Semiconductor laser light source device 4: External lead 5: Heat sink 6: Casing member 7: Window member 10: Semiconductor laser chip 11: Light emission area 12: Light flux 20: Semiconductor laser chip 21: Light emission area 22: Light flux 30 : Refractive optical system 30A: Optical axis of refractive optical system 30xf: Second focus of refractive optical system 30yf: First focus of refractive optical system 31: Lens 32: First lens 33: Second lens 34: First lens 35: Second lens 40: Specific position 100: Semiconductor laser chip 101: Light emission area (emitter)
101L: Ray bundle emitted from the emitter 102: Collimating lens 120: Light source module 121: Submount θ _y : Divergence angle in the fast axis direction θ _x : Divergence angle in the slow axis direction

Claims (9)

Heatsink,
A plurality of semiconductor laser chips formed on the upper surface of the surface of the heat sink and having a light emitting region;
A light flux emitted from the light emission region of the plurality of semiconductor laser chips is incident, and a refraction optical system that changes the traveling direction and emits is provided,
The at least two semiconductor laser chips are orthogonal to the surface of the heat sink so that the chief rays of the light flux emitted from the light emission regions of the respective semiconductor laser chips are not parallel to each other. When viewed from the direction, they are arranged at an angle to each other,
The refracting optical system is orthogonal to the optical axis direction and the first direction, which is a focus on a first plane formed by the first direction and the optical axis direction of the refracting optical system. A semiconductor laser light source device, wherein a second focal point, which is a focal point on a second plane formed by the second direction, is composed of an optical system displaced in the optical axis direction. When the distance in the second direction between the chief rays emitted from the light emitting regions of the adjacent semiconductor laser chips is d1,
The plurality of semiconductor laser chips, in the optical axis direction, from the light emitting region to a specific position on the light emitting region side with respect to the refractive optical system, as the semiconductor laser chips progress in the optical axis direction. The semiconductor laser light source device according to claim 1, wherein the semiconductor laser light source devices are arranged so as to be inclined with respect to each other so that the distance d1 becomes small. The semiconductor laser light source device according to claim 2, wherein the second focal point is located closer to the refractive optical system than the first focal point in the optical axis direction. The second principal rays obtained by virtually extending the principal rays emitted from the light emitting regions of the adjacent semiconductor laser chips in the direction opposite to the refractive optical system, If the distance related to the direction is d1,
The plurality of semiconductor laser chips, in the optical axis direction, in a direction opposite to the optical axis direction from a virtual light emitting area corresponding to an end surface at a position opposite to the light emitting area to a specific position. 2. The semiconductor laser light source device according to claim 1, wherein the semiconductor laser light source devices are arranged so as to be inclined with respect to each other so that the distance d1 becomes smaller as the distance d1 goes to the next direction. The semiconductor laser light source device according to claim 4, wherein the second focus is located on a side farther from the refractive optical system with respect to the optical axis direction than the first focus. The refraction optical system is configured by a single lens having a different focal length in the first direction and a focal length in the second direction, and any one of claims 1 to 5, wherein 2. A semiconductor laser light source device according to item 1. The refraction optical system,
With respect to the light flux emitted from the light emission region, a divergence angle in the first direction is reduced, and a first lens having the first focus as a focus,
A second lens having a second focus as a focal point, which is disposed in the latter stage of the first lens and reduces the divergence angle in the second direction with respect to the light flux emitted from the light emission region. It has, The semiconductor laser light source device of any one of Claims 1-5 characterized by the above-mentioned. The refraction optical system,
With respect to the light flux emitted from the light emission region, reducing the divergence angle in the first direction and the second direction, a first lens having the first focus as a focus,
A second lens having a second focus as a focal point, which is disposed in the latter stage of the first lens and reduces the divergence angle in the second direction with respect to the light flux emitted from the light emission region. It has, The semiconductor laser light source device of any one of Claims 1-5 characterized by the above-mentioned. The semiconductor laser light source device according to claim 1, wherein the plurality of semiconductor laser chips are connected in series.

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