JPH04323531A - Life span measurement device for lamp - Google Patents

Abstract

PURPOSE:To achieve safe measurement without using by mercury by judging, noticing the life span of a lamp based on the change in the characteristic thereof detected according to the lighting of the lamp. CONSTITUTION:A part of the emitted light of a lamp 1 is injected into a light receiving element 2 serving as a characteristic detection means. The detected signal is amplified by an amplifier 3, which is reset at the time of replacing the lamp 1 for a new one, and the gain of which is corrected by a corection means 8, and the signal is input into a display means 4. An analog voltmeter 5, which has a graduation part 6 divided into red and green parts, and which displays the green or red part according to a using period within the life span and the end of the life of the lamp 1 through a pointer 7, is used for the means 4. The voltage input into the voltmeter 5 is changed according to the output of the element 2 correspondent to the brightness of the using condition of the lamp 1, which is indicated through the green or red part according to the remaining life span. A digital display device 13 is also used for the means 4. Safe measurement is thus carried out by the lighting characteristic of the lamp 1 without using mercury.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lamp life measuring device for measuring the life of a lamp in, for example, an endoscope illumination light source device.

0002

2. Description of the Related Art For example, a light source device for an endoscope uses a high-intensity lamp, which generally has a short lifespan. When a high-intensity lamp reaches the end of its life, its light intensity decreases, and when it is used, the field of view in an endoscope becomes dark.

Conventionally, life meters have been known that display the cumulative usage time of consumable parts such as heads in video decks and the like in order to check the lifespan of the consumable parts. In this conventional life meter, mercury and an electrolytic solution are placed in a container, and the cumulative usage time can be determined from the amount of mercury transferred in the electrolytic solution due to an electric field reaction.

0004

[Problems to be Solved by the Invention] Conventional life meters use mercury, which poses problems from an environmental and safety perspective. In recent years, the use of mercury has been restricted, and it has been desired to provide a life meter that does not use mercury.

The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a life meter that is safe without the use of mercury and is capable of measuring the life of a lamp. .

[0006]

[Means for Solving the Problems and Effects] The first invention includes a characteristic detecting means for detecting a characteristic that changes as the lamp is lit, and a characteristic detecting means that detects the life of the lamp from the change in the characteristic detected by the characteristic detecting means. lamp life determination means for determining;
The lamp includes a means for notifying that the life of the lamp has been reached when the life of the lamp is determined by the lamp life determination means.

[0007] The second invention includes a lamp characteristic detection means for detecting lamp characteristics when the lamp is lit, and a lamp characteristic detected by the lamp characteristic detection means when the lamp is initially lit. a lamp life determination means for determining the lamp life at a given time and determining the lamp life from a change in the lamp characteristics; It is equipped with a means for notifying.

[0008]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 conceptually shows the configuration of a lamp life measuring device according to a first embodiment of the present invention. Reference numeral 1 denotes a high-intensity lamp incorporated in, for example, an endoscope illumination device. The light L emitted from the lamp 1 is made to enter the light guide of the endoscope through an output optical system (not shown). A part of the light L emitted from the lamp 1 enters the light receiving element 2 as a characteristic detecting means at a certain rate. The detection signal of the light receiving element 2 is amplified by the amplifier 3 and inputted to the display means 4.

As the display means 4, for example, an analog voltmeter 5 as shown in FIG. 1(b) is used for visual display. This analog voltmeter 5 has a scale part 6 divided into red and green parts, and the pointer 7 points to the green part when the lamp 1 is in the usage period before the end of its life, and when it has reached the end of its life. points to the red part.

Settings for this purpose are performed by a correction means 8 for correcting the gain of the amplifier 3. That is, this correction means 8 is used as a means for resetting when the lamp 1 is replaced with a new one, and the analog voltmeter 5 is adjusted in consideration of the initial brightness of the lamp 1 used, its dimming characteristics, etc.
Set the pointer 7 so that it indicates the initial value.

As the lamp 1 is used, its brightness gradually decreases, the output of the light receiving element 2 also decreases, and the voltage input to the analog voltmeter 5 decreases accordingly, but it remains within a usable range. As long as the pointer 7 of the analog voltmeter 5 is located in the green area, it indicates a usable state.

However, when the life of the lamp 1 comes to an end and its brightness drops to an unusable range, the life of the lamp 1 is judged based on the decrease in the amount of light received by the light receiving element 2. Therefore, the analog voltage The voltage input to the total 5 also decreases accordingly.

Due to this change in lamp characteristics during lighting,
The pointer 7 of the analog voltmeter 5 serving as a display means moves away from the green part and points to the red part to notify that the life of the lamp 1 has expired. The user sees this and replaces the lamp 1 with a new one. Since it is displayed analogously with pointer 7,
It can be easily predicted before the end of life.

Note that instead of these, a configuration as shown in FIG. 1(c) may be used. That is, the output of the amplifier 3 that amplifies the detection signal of the light-receiving element 2 is converted into a digital signal by the A/D converter 11, this digital signal is calculated by the counter 12, and the digital display device 13 displays and announces the digital signal. do. This digital display device 13
For example, a 7-segment LED or a liquid crystal display is used.

FIG. 2 conceptually shows the configuration of a lamp life measuring device according to a second embodiment of the present invention. That is, the emitted light L of a high-intensity lamp 1 incorporated in, for example, an endoscope illumination device is made to enter a light guide of an endoscope through an output optical system (not shown). Further, the means for detecting the characteristics of the lamp is such that a part of the light L emitted from the lamp 1 is made incident on the light receiving element 2 at a certain rate, similar to the above-described embodiment. A detection signal from the light receiving element 2 is amplified by an amplifier 3.

The output of the amplifier 3 is transferred from the A side terminal to the first A/D converter 16 through the signal switching means 15, and then from the B side terminal to the first A/D converter 16.
The signal is selectively input to the second A/D converter 17 from the side terminal. The output of the first A/D converter 16 is input to the memory 18. The reference value setting means 19 uses the data stored in the memory 18 to set a predetermined reference value.

Comparing means 20, which constitutes means for determining the life of the lamp 1 from changes in lamp characteristics during lighting, compares the reference value with the output value of the second A/D converter 17. When the output value becomes less than the reference value, a display drive signal is sent to the display means 4. As the display means 4, for example, a method such as lighting a warning light can be considered.

When the lamp 1 is replaced with a new one, the signal switching means 15 automatically or manually switches the terminal to the A side. A value corresponding to the light amount of the lamp 1 at this time is stored in the memory 18. Then, (b
), if the time when the light intensity of the lamp 1 decreases to 50% or less is the end of the life of the lamp 1, then that value should be compared with the output value of the second A/D converter 17.
Use as standard value.

After this setting operation is completed, the signal switching means 15 is automatically or manually switched to the A side terminal. The amount of light from the lamp 1 that is turned on as the lamp is normally used is detected in real time, and the output from the second A/D converter 17 is compared with the reference value by the comparing means 20.

When the light intensity of the lamp 1 decreases to 50% or less, a signal for driving a warning operation is sent from the comparison means 20 to the display means 4, and the display means 4 is driven, indicating that the lamp 1 has reached the end of its life. Warn.

[0021] Incidentally, incandescent bulbs, laser diodes, L
Light emitting elements such as EDs have a limited lifespan. Therefore, the value of the correspondence between the lifespan curve of this incandescent bulb or light-emitting element and the lifespan curve of the lamp of the device under test that is lit at the same time is stored in memory in advance, and the lighting characteristics of the incandescent bulb or light-emitting element are If the usage time of the lamp is calculated from the time it takes to reach the reference value, then the life of the lamp can be measured in the same manner as described above.

Furthermore, when this type of incandescent bulb or light emitting element is operated under overload, its lifespan is shortened, as shown in FIG. Therefore, by storing this lifespan curve in memory in advance and calculating the time until it reaches a predetermined reference value, it is possible to more easily measure the lifespan of consumable parts such as other lamps, as described above. .

FIG. 4 conceptually shows the configuration of a lamp life measuring device according to a third embodiment of the present invention. That is, the color temperature sensor 22 uses a part of the luminous flux of the emitted light L of the high-intensity lamp 21 in the endoscope illumination device as described above.
The purpose is to detect the spectral distribution and determine the lifespan of the lamp 21 from changes in this spectral distribution.

Generally, as the usage time of the lamp 21 increases, the spectral distribution shifts from the initial spectral distribution shown by the solid line to the spectral distribution shown by the dotted line, as shown in FIG. 4(c). The color temperature sensor 22 detects this characteristic.

The detection signal of the color temperature sensor 22 is sent to the amplifier 23.
is amplified. Comparison means 24 compares the output of amplifier 23 with the reference value output from memory 25 to determine the lifespan of lamp 21. The memory 25 stores a color temperature value (reference value) when the lamp 21 reaches the end of its life, taking into account the color temperature of the lamp 21 when it is new. And comparison means 24
is compared with the detected value from the color temperature sensor 22 using this reference value, and when the detected value reaches the reference value, the display means 26
Outputs display drive signals to. As the display means 26, for example, a method such as lighting a warning light can be considered.

[0026] When the lamp 21 is replaced with a new one, a reference value corresponding to the life characteristics of the lamp 21 is stored in the memory 25.
to be memorized. Then, the color temperature of the lamp 21 is detected in real time by the color temperature sensor 22. When the detected value of the color temperature sensor 22 reaches the reference value, the comparison means 24 outputs a drive signal, drives the display means 26, and notifies that the lamp 21 has reached the end of its life.

As shown in FIG. 4(b), instead of the color temperature sensor 22, a normal light receiving element 28 and a color temperature correction filter 29 combined therewith are used to adjust the transmittance of any wavelength. The life of the lamp 21 may be measured by detecting the change in characteristics of the lamp 21.

FIGS. 5(a) and 5(b) show a lamp life measuring device according to a fourth embodiment of the present invention. This is provided with a light emitting element, for example an LED 31, which lights up corresponding to the lighting time of the lamp while the lamp, which is a consumable part in the device under test, is on, and this LED 31 is connected to the measurement circuit 32 of the device under test. That is, the LED 31 is used in place of the lamp described above. This is used to indirectly detect lamp characteristics. according to this,
There is no need to install a light receiving element or the like near the measurement target.

The light from the LED 31 is converted into an electrical signal by the photoelectric conversion means 33. This electrical signal is stored by a storage means 34, and a display means 35 consisting of a voltmeter or the like displays the cumulative usage time of the lamp according to the value. Note that the full scale of the display means 35 can be adjusted using a resistor or the like.

The photoelectric conversion means 33 is shown in FIG.
It may be a phototransistor 36 as shown in b),
A photoresistive element such as CdS may also be used. When a phototransistor 36 is used, the current-converted detection signal is appropriately amplified by an amplifier 37, integrated by a storage means 34 consisting of a resistor R and a capacitor C, and the time during which electricity is applied to the lamp is stored as an elapsed time. . Then, the value of the accumulated elapsed time is displayed on the display means 35. The full scale of the display means 35 is adjusted using a resistor or the like.

Note that the light from the LED 31 may be attenuated by a filter or the like and then made to enter the phototransistor 36. In addition, the lamp of the device to be measured is connected to the LED 3.
If it is used directly instead of 1, the light emitting element can be omitted. Furthermore, while the lamp, which is a consumable part in the device under test, is lit, changes in the characteristics of the light emitting element, such as the LED 31, which is lit corresponding to the lighting time of the lamp are detected, thereby indirectly determining the lifespan of the lamp to be measured. The determination may be made as follows.

FIG. 5(c) shows a modification of the photoelectric conversion means and storage means. In other words, this is a photoelectric conversion means that receives light from a lamp as a consumable part in the device under test, or receives light from a light emitting element or the like that is turned on in accordance with the lighting time of the lamp, and uses a silver halide film AG and a front surface of this circle. The light attenuating filter F provided above is stacked on top of the other.

Generally, the electrical resistance of silver salt film AG increases as it is exposed to light. In other words, at the same time as photoelectric conversion, there is an integration and accumulation function for the exposure amount (the product of the incident light amount and time), and here we will use this as a means to detect the characteristics that change depending on the lighting of the lamp and to determine the lamp life. It is used as a means to

Therefore, a constant voltage power supply 41 is connected to this silver halide film AG, and the voltage drop caused by the increase in electrical resistance of the battery silver halide film AG is amplified and outputted by an amplifier 42.
From that value, the display means displays the value of the cumulative usage time.

FIG. 5(d) shows the above-mentioned silver salt film AG.
This is an example in which a liquid crystal device (LCD) 46 divided into a plurality of bar portions 45 is used as a display means in a configuration that utilizes the characteristic that electrical resistance changes depending on the amount of light exposure, and each bar portion 45 has a step display. It lights up to display the elapsed usage time. The elapsed usage time of the lamp can be determined by the number of lit bar portions 45.

Note that when the circuit to be measured includes a heat generating element such as a heater or a lamp, a means for detecting the energization time can be configured using a heat sensitive sensor such as a POSISTOR or a platinum resistor. Alternatively, a resistor may be inserted into the conversion circuit, and the heat generated by the resistor may be used as the energization time.

FIG. 5(e) shows an embodiment that utilizes the characteristic of a lamp that the lamp voltage gradually increases as it is used. This detects the voltage across the lamp 51, which is a consumable part of the device under test, and when replacing the lamp 51 with a new one, writes the initial voltage into the memory 52, and stores the lamp voltage detected in real time and the stored initial voltage. A subtracter 53 subtracts the voltage from the subtracter 53, and the output of the subtracter 53 is converted into a 3-bit binary signal by an A/D converter 54, thereby driving a display means 55.

[0038]

Effects of the Invention As explained above, the present invention measures the lamp life using the lighting characteristics of the lamp or those whose characteristics change accordingly, so it is safe without the use of mercury, and the lamp It is possible to provide a life meter that can measure the lifespan of.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a schematic configuration of a lamp life measuring device according to a first embodiment of the present invention.

FIG. 2 shows a lamp life measuring device according to a second embodiment of the present invention, (a) is an explanatory diagram of its schematic configuration, (b)
) is a characteristic diagram showing the dimming characteristics with respect to the usage time of the lamp.

FIG. 3 is a diagram showing the life characteristics of a general light receiving element.

FIG. 4 shows a lamp life measuring device according to a third embodiment of the present invention, in which (a) is an explanatory diagram of its schematic configuration, and (b)
) is an explanatory diagram showing a modification thereof, and (c) is a characteristic diagram showing changes in spectral distribution with respect to usage time of the lamp.

FIGS. 5(a) and 5(b) show a lamp life measuring device according to a fourth embodiment of the present invention, and FIGS. 5(c), 5(d), and 5(e) are explanatory diagrams showing different modifications, respectively.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1... Lamp, 2... Light receiving element, 3... Amplifier, 4... Display means, 5... Analog voltmeter, 8... Correction means, 21... Lamp, 22... Color temperature sensor, 24... Comparison means, 26... Display means, 31...LED, 33...Photoelectric conversion means, 34...Storage means, 35...Display means, 36...Phototransistor, 46
...Liquid crystal device, 51...Lamp, AG...Silver salt film.

Claims (2)

[Claims] 1. A characteristic detecting means for detecting a characteristic that changes as the lamp is lit; a lamp life determining means for determining the life of the lamp from a change in the characteristic detected by the characteristic detecting means; and a lamp life determining means for determining the life of the lamp. 1. A lamp life measuring device comprising means for notifying that the life of the lamp has been reached when the life of the lamp is determined by the means. 2. A lamp characteristic detecting means for detecting lamp characteristics when the lamp is lit, and a lamp characteristic when the lamp is lit during use based on the lamp characteristics detected by the lamp characteristic detecting means when the lamp is initially lit. a lamp life determination means for determining the life of the lamp from a change in the lamp characteristics; and a means for notifying that the life of the lamp has been reached when the lamp life determination means determines that the life of the lamp has been reached. A lamp life measuring device characterized by comprising: