JP2724249B2 - Adjustment jig for lens performance inspection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jig for a lens performance inspection apparatus for inspecting the performance of a lens, and more particularly, to a lens performance inspection such that the focus of a lens to be inspected coincides with the focus of an objective lens for inspection. The present invention relates to an adjustment jig for performing an initial adjustment.

[0002]

2. Description of the Related Art Conventionally, a lens performance inspection apparatus as shown in FIG. 5 has been employed to inspect the optical performance such as the focal length of a lens. This device includes a collimator 10, a main body 12, a CCD camera 14, and the like.
The collimator 10 is an instrument in which a focusing plate 18 is disposed at the focal point of the objective lens 16 and the light transmitted through the focusing plate 18 is converted into a parallel light beam, as is well known. The reticle 18 has a chart 18a as shown in FIG. 3 formed by direct photo-etching or the like based on a transparent glass disk. Main body 12
Comprises a lens holder 20 to which the lens 19 to be tested is attached, and a mount 24 to which the microscope objective 22 is fixed. The lens holder 20 is provided with a reference surface 20a on which the lens 19 to be tested is placed, and the lens 19 is attached to the lens holder 20 from a vertical direction. The lens holder 20 is screwed into the mount 24, and the distance L between the reference plane 20 a and the focal point of the microscope objective lens 22 can be adjusted by rotating the lens holder 20. Note that a scale is provided on the mount section 24. This scale measures the vertical movement distance of the lens holder 20 with respect to the mount part 24, and the scale L can be read by a numerical value.

In order to inspect the performance of a lens using such an apparatus, first, an adjustment operation for setting the interval L shown in FIG. 5 to "0" is required. In this operation, the image of the chart 18a on the collimator 10 side is required. Instead of observing the image on the monitor CRT 28, an image of the chart of the glass member is formed by illuminating collimated light on a glass member on which a chart as shown in FIG. Observe on monitor CRT28. The glass member is placed so that its chart forming surface is in contact with the reference surface 20 a of the lens holder 20. Then, the distance L is adjusted by rotating the lens holder 20 to a position where the image of the chart of the glass member can be observed well on the monitor CRT 28. According to this, the interval L is always “0”, and the reference of the scale provided on the mount portion 24 at this position is matched.

After the adjustment work is completed, a lens performance test is started. In the lens performance inspection, the collimated light is transmitted through the lens to be inspected 19 and an image is formed at the focal point of the lens. The aerial image is received by the CCD camera 14 via the microscope objective lens 22 and the reflection plate 26, and the image of the chart 18a provided on the collimator 10 is displayed on the monitor CRT 28.
Projected on. Then, the operator places the lens holder 20 at a position where the projected image of the chart 18a can be observed well.
To rotate. The interval L at this time is read on the scale of the mount unit 24, and the read value is compared with the focal length determined in the design of the lens 19 to be tested.
9 is to inspect the performance such as back focus.
The chart 18 displayed on the monitor CRT 28
Since the image a is transmitted through the microscope objective lens 22, it is projected in an enlarged state, so that the operator can easily read the image of the chart 18a.

[0005]

However, the work of performing the above-mentioned adjustment work has been performed by a skilled person. This is because this adjustment work is performed on the monitor CRT28.
In the past, the collimated light was illuminated on the chart of the glass member, so the amount of light was insufficient, and the image of the chart was projected on the monitor CRT 28 in a slightly dark state. There was a disadvantage that it was difficult to read. Incidentally, if the interval L is positioned while the image of the chart is not best displayed, it will affect all the performance inspections of the lens 19 to be inspected.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described drawbacks, and provides an adjustment jig which makes it easy to read a chart displayed on a monitor CRT and allows an adjustment operation to be performed with a simple operation. With the goal.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned drawbacks, the present invention provides a cylindrical portion having a contact surface which abuts a reference surface on which a lens to be tested is mounted, protruding from an outer periphery,
An adjustment including a light-transmissive chart portion housed in the cylindrical portion and provided at a focal position of the inspection lens from the contact surface, and a light source for providing illumination light to the chart portion from the cylindrical portion. By using a jig, the adjustment work of the lens performance inspection apparatus can be simplified.

[0008]

FIG. 1 shows an adjusting jig according to the present invention. The adjustment jig 30 is a jig for adjusting the distance L between the reference surface 20a of the lens holder 20 and the focal point of the microscope objective lens 22, as shown in FIG. The jig 30 has a contact surface 32 protrudingly provided on the outer periphery of the cylindrical portion 31 and in contact with the reference surface 20a. The light emitting element 33 and the glass plate 35 are built in the cylindrical portion 31. As the light-emitting element 33, a near-infrared light-emitting diode having a center emission wavelength of 880 nm is used, corresponding to the lens to be measured being a lens for distance measurement used for near-infrared light. The light emitting element 33 is fixed to the substrate 34 by soldering. As shown in FIG. 2, a switch 38, a power supply 39, and a power source 39 are provided between the terminal portions 33a and 33b of the light emitting element 33 fixed to the substrate 34.
The resistor 40 is connected.

The transparent glass plate 35 is arranged below the jig 30. A chart 37 is formed on the glass plate 35 by direct photo-etching or the like, and the chart 37 has black and white stripes displayed at equal intervals as shown in FIG. The chart 37 forming surface and the contact surface 32
Distance L ₁ between has a distance corresponding to the focal length of the lens. Therefore, the length of the cylindrical portion 31 along the optical axis P is also a length corresponding to the focal length of the test lens.

Next, the operation of the above configuration will be briefly described.
When performing an adjustment work using this adjustment jig 30, first,
The operator mounts the adjustment jig 30 on the lens holder 20 by mounting the adjustment jig 30 from the vertical direction such that the contact surface 32 of the adjustment jig 30 comes into contact with the reference surface 20a of the lens holder 20 shown in FIG. This results in the state shown in FIG. Thereafter, when the switch 38 of the circuit shown in FIG. 2 is turned on, the light emitting element 33 is turned on, and the chart 37 is illuminated.

Therefore, the monitor CRT2 shown in FIG.
In FIG. 8, the chart 37 provided on the adjustment jig 30 is clearly illuminated by the illumination of the light emitting element 33. This allows
The operator rotates the lens holder unit 20 while reading the projected chart 37, and adjusts the interval L shown in FIG. 5 so that the image of the chart 37 is clearly displayed on the monitor CRT. The interval L when the image is clearly projected on the monitor CRT 28 is an interval corresponding to the designed focal length of the lens to be inspected.
Then, the light source of the collimator 10 is turned on after the test lens is mounted on the reference surface 20. If the test lens is appropriate, the image of the chart 18a of the collimator 10 is correctly displayed on the monitor CRT 28. If the focal length of the test lens is incorrect or the optical axis is decentered, the monitor CRT 28 Since the image quality of the projected image of the chart 18a deteriorates, it is possible to inspect the suitability or unsuitability of the lens to be inspected.

In the present embodiment, the chart portion is formed by directly forming the chart 37 on the glass plate 35 by photo-etching or the like.
A polyester film or the like on which a photo is printed
May be bonded with a lens bond or the like, an acrylic plate may be used in place of the glass plate 35, or the surface of the acrylic plate or the glass plate or the like without using the chart 37 may have a light-diffusing surface. It is also possible to use as.

In this embodiment, the collimator 10 and the adjustment jig 30 are provided with charts 18a and 37 as shown in FIG.
However, instead of the charts 18a and 37, a chart plate provided with a pinhole or the like may be used.

[0014]

As described above, according to the present invention, since the adjusting jig is provided with the chart plate and the light source, the optical path length of the light source for providing illumination light to the chart plate becomes shorter as compared with the prior art. The chart image projected on the monitor CRT becomes easy to see. As a result, the adjustment work time is shortened, and an accurate adjustment work can be performed.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an adjustment jig according to the present invention.

FIG. 2 is a circuit diagram showing an electrical configuration of an adjustment jig.

FIG. 3 is a front view showing a chart.

FIG. 4 is a cross-sectional view of a main part showing a state where an adjustment jig is attached to a lens performance inspection device.

FIG. 5 is an explanatory diagram showing a schematic configuration of a lens performance inspection device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Collimator 14 CCD camera 16 Objective lens 20 Lens holder part 22 Microscope objective lens 24 Mount part 28 Monitor CRT 30 Adjusting jig 32 Contact surface 31 Cylindrical part 33 Light emitting element 35 Glass plate 18a, 37 Chart

Claims (1)

(57) [Claims] 1. A lens comprising: a lens holder on which a reference surface on which a lens to be tested is mounted is formed; and a mount which supports the lens holder so as to be able to move up and down and to which an inspection objective lens is fixed. Used for performance inspection equipment,
An adjusting jig used for positioning the lens holder so that the focus of the test lens coincides with the focus of the inspection objective lens when the test lens is mounted on the reference surface; A cylindrical portion formed with a contact surface protruding from the outer periphery in contact with the optical member; a light-transmissive chart portion provided in the cylindrical portion and provided at a focal position of the inspection lens from the contact surface; An adjustment jig for a lens performance inspection device, comprising: a light source that supplies illumination light to the chart section from within the section.