JP3523675B2 - Dimming circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention supplies an object to be imaged.
The present invention relates to a dimming circuit for dimming illumination light. [0002] 2. Description of the Related Art In recent years, the development of video cameras and the like is remarkable.
In imaging means used for video cameras and the like,
By adjusting the exposure based on the light from the subject, the subject image
There have been proposed various imaging devices that reliably capture images. this
By providing a light source device in these imaging devices,
Some objects illuminate the body with appropriate illumination light to capture images.
You. In such a light source device, the image pickup device
Provide a dimming circuit that dims the illumination light supplied to the body
Was. The conventional dimming circuit is proportional to the quantity of light of the subject.
The signal obtained by integrating the integrated video signal with the reference signal
Drive the aperture according to the difference, and
When the operation is performed so that the signals obtained by integrating the image signals match,
In addition, hunting is suppressed by a phase compensation circuit. Further, for example, in order to improve the response,
As shown in Japanese Unexamined Patent Publication No. Hei.
Variable loop gain depending on the position or opening,
One that changes the loop gain or response speed according to body illuminance
The law has been taken. [0005] SUMMARY OF THE INVENTION
In the conventional configuration, an image pickup signal from a video camera or the like is processed by a signal.
Of a CCU to manage and a light source to supply illumination light to the subject
Combination of CCU and light source with limited setting
Must properly perform dimming operation only in the specified combinations.
There is a problem that can not be. The present invention has been made in view of the above circumstances.
And the combination of the imaging means and the light source means is limited.
No hunting occurs without adjustment, smooth operation
It is an object to provide a dimming circuit having excellent responsiveness. [0007] The dimming circuit of the present invention comprises:Suffered
Illuminate the objectIllumination light supply means for supplying illumination light,Previous
Inserted into and removed from the optical path between the object and the illumination light supply means.
Aperture means for restricting the illumination light;
Before the illumination light supplied by the light supply meansThe subject
Light amount detecting means for detecting the amount of the returning light,Predetermined response
Driving the diaphragm means in response,The light amount detecting means detects
The amount of the returning light emittedAnd a predetermined reference light amount
So that the difference is smallLight that controls the amount of illumination light
Volume control means;Based on the input of the execution operation from outside,
Over the entire range of the light quantity limit of the illumination light by the diaphragm means.
Therefore, according to the ratio of limiting the illumination lightLight intensity control
Calculating means for calculating a correction value for correcting the responsiveness of the means;
A correction value storage for storing the correction value calculated by the calculation means;
With means of memoryIt is characterized by having. [0008] 1 to 14 relate to a first embodiment of the present invention.
FIG. 1 shows a light source device as a first embodiment of the dimming circuit.
FIG. 2 is a configuration diagram showing the configuration of the endoscope device obtained in FIG.
FIG. 3 is an external view showing the appearance of the device, and FIG.
FIG. 4 is an enlarged view of the duct body of the light source device of FIG.
FIG. 5 is an enlarged view of a modification, and FIG.
Fig. 6 and Fig. 6 show the configuration of the optical system for the illumination light from the lamp in Fig. 1.
FIG. 7 shows a diaphragm used in the optical system of FIG.
FIG. 8 is a configuration diagram showing an example of the configuration of the aperture spring.
FIG. 9 is an explanatory view for explaining the structure of the light transmitting hole, and FIG.
Configuration showing the configuration of a first modification of the used diaphragm spring
FIGS. 10 and 10 show a second example of the diaphragm spring used in the optical system of FIG.
FIG. 11 is a configuration diagram showing a configuration of a modification of FIG.
FIG. 12 is a cross-sectional view showing the detailed configuration of the second modification of the second embodiment.
The stop position and stop amount of the stop splash by the light source device of FIG.
FIG. 13 is a characteristic diagram showing the relationship between the aperture ratios, and FIG. 13 is an electronic endoscope of FIG.
And graph showing the characteristics of the output of the CCD with respect to the incident light of FIG.
Reference numeral 14 denotes a dimming loop gay by the CPU of the light source device of FIG.
FIG. 9 is an explanatory diagram for explaining the correction of the noise. The endoscope device of the first embodiment is shown in FIG.
Thus, an electronic endoscope 1 inserted into a body cavity,
A camera that inputs an output signal of the endoscope 1 and outputs a video signal
LA Control Unit 2 (hereinafter referred to as CCU)
A light source device 3 for supplying light to the electronic endoscope 1.
The CCU 2 transmits the subject image in the electronic endoscope 1 to the electronic endoscope 1.
Amplifies the output signal of the solid-state imaging device 4b for converting the output signal into an air signal.
Preamplifier 5 and an output signal of the preamplifier 5
DC conversion circuit 6 for smoothing with a time constant of
It is composed of a processing circuit. The light source device 3 is used by an operator to operate a panel.
Outputs a signal according to the brightness that can be set to more arbitrary brightness.
A reference signal generating circuit 7 for outputting the output of the DC converting circuit 6
A signal is input and the ratio is compared with the output signal of the reference signal generation circuit 7.
A comparison circuit 8 for comparing and outputting a difference;
The output signal switches gain according to an external control signal
Gain control amplifier (hereinafter referred to as GCA) 9
And a phase correction circuit 10 for correcting frequency characteristics, and a subject
And a light amount emitted from the lamp 11
The aperture 12 to be squeezed and the aperture to move the aperture 12
In conjunction with the spring drive unit 18 and the drive shaft of the diaphragm spring 12
A potentiometer 13 whose axis moves,
Input the output and the output of potentiometer 13
And a CPU 14 connected to the CPU 14
An address signal corresponding to the output of the potentiometer 13
An external memory for storing the operation data of the CPU 14 according to the signal
Memory 15 and an address signal of the external memory 15.
After reading the same data by the CPU 14,
Input to the GCA9 gain switching control terminal.
Gain switching signal generating circuit 16 and the CPU
14 and the output of the phase correction circuit 10
Starts a predetermined operation based on the output of the optical set SW and then ends.
Until the process is completed, the selection of the output of the CPU
And a changeover switch 17, and
Illumination light is inserted into the electronic endoscope 1 through a diaphragm spring 12.
Transmitted to the distal end of the electronic endoscope 1 by the light guide 4a passing therethrough.
It is sent and illuminated in front of the tip. The light source device 3, as shown in FIG.
A duct body 22 is fixed to the housing 21 of the source device 3 from the inside.
Have been. As shown in FIG.
Cover that covers the entire body 22 with almost the same area.
A shoe 23 is attached by a screw 25. Hippo
-Four leaf springs 24 are integrally fixed to the mesh 23.
Have been. The leaf spring 24 is vacant in the housing 21 in a no-load state.
Larger than the mounting hole of the duct body 22
You. In this structure, the duct body 22 and the cover
Attachment holes for housing 21 from outside with mesh 23
Into the plate mesh integrated with the cover mesh 23.
When the screw 24 spreads through the hole of the housing 21,
The duct body 22 is fixed to the housing 1 by the elastic force of the leaf spring 24
Is done. With such a structure, the duct body 22
Can be easily and quickly fixed to the housing 21 without using tools.
To be able to The configuration of a modification of the duct body 22 will be described.
Thus, a configuration as shown in FIG. 4 can be obtained. Sand
The configuration is almost the same as that of FIG.
The mesh 26 and the four thin springs 27 are fixed by screws 25.
Is defined. The fine spring 27 is a duct body 22 of the housing 21.
Can be rotated in parallel with the mounting surface of the
Two projections 28 are provided in the rotation circumference of the spring 27, respectively.
It is. FIG. 5 shows an enlarged view of the thin spring 7 and the projection 8 of the housing 1.
You. In this configuration, the duct body 22 and the mesh
And insert it into the mounting hole of the housing 21 from outside.
After rotating the four fine springs 27, the
It is moved between the two projections 28. Then four fine springs
27, the duct body 22 is fixed to the housing 21.
It is. With such a structure, as in FIG.
The body 22 can be easily and quickly attached to the housing 21 without using tools.
Can be fixed. Here, in the diaphragm spring 12 of this embodiment, the conventional
Can be used with a different configuration
You. That is, as shown in FIG. 6 and FIG.
The aperture spring 12 with a cut 35 is installed in the light source device 3.
The installation position is the same as the circle of the fan of the aperture spring 12.
With the same rotation center and a certain distance from the rotation center
The trajectory 37 on the line 12 is always the lamp 11, the condenser lens group 32
The hole 36 is set as the rotation center so as to pass through the optical axis 31 passing through the central axis of
And is rotatably fixed. The aperture spring 12 is arranged at equal angles through a hole 36.
Transmit light at equal intervals on the trajectories a, b, c, ..., m, ...
A hole 38 is provided, and the light transmitting hole 38 is formed as shown in FIG.
Perpendicular to the aperture spring 12 on the trajectory a, b, c,
…, Open while tilting with respect to the optical axis 31 as going to m
Have been. The light transmitting holes 38 are holes having the same angle on the same line.
Is open. Further, the outer peripheral gear 35 of the aperture spring 12
Is directly connected to the motor 18a as the aperture driving unit 18.
Spur gears are connected. The aperture spring 12 is driven by a motor 18a.
As the light is rotated, the light transmitting hole 38 becomes a trajectory with respect to the optical axis 31.
It changes from on a to trajectory m. The light transmitting hole 38 is as described above.
As the optical axis 31 goes from the trajectory a to the trajectory m
Of the lamp light passing through the diaphragm spring 12
The amount of over light changes. That is, there is a problem such as suppression of hunting of the diaphragm.
The gear must have a certain reduction ratio or higher,
The diameter must be increased, and the aperture drive mechanism becomes larger
However, although this is disadvantageous for downsizing the equipment, the outer peripheral gear 35 is provided.
A light transmitting hole 3 as an aperture adjusting element is provided inside the aperture spring 12.
8 and the aperture spring 12
By removing the outer gear part and making it a fan shape, a circular gear
Compared to this, the aperture drive mechanism has been downsized and the number of parts has been reduced.
It is possible to improve the assemblability due to the reduction. As shown in FIG. 9, the stop shown in FIG.
An aperture spring 12a, which is a modification of the spring 12, is shown in FIG.
The light transmitting holes 38 arranged on the base lines a, b, c,.
By changing the inclination with respect to the optical axis 31 and changing the amount of transmitted light
On the other hand, in the case of the diaphragm spring 12a, the optical axis of the passing light
There is no inclination of the light transmitting hole 38 with respect to 31 and all are vertical.
However, the diameter of the hole gradually decreases as going from trajectory a to trajectory m.
In other words, the configuration can be made by changing the amount of transmitted light. The diaphragm spring 12 other than those shown in FIGS.
A modified example of 12a may have the following configuration.
No. That is, an aperture for adjusting the light quantity of the light source device
In the spring 12b, as shown in FIG.
A hole 42 whose size changes due to photocorrosion
By changing the opening area of the area
Adjust the amount of light emitted by the light source by changing the amount of light transmitted through the spring
You. Here, in order to reduce the amount of light emitted from the light source to the limit,
The total opening area of all the holes 42 in the region 43 where light is most focused is reduced.
If you reduce the number of holes 42, the light distribution of the light source
To reduce the diameter of the hole 42 without reducing the number of holes 42
Must be combed. However, conventional SUS materials
In the method of making holes in the material by photocorrosion, the dimensions are the same as the thickness of the base material.
Limiting the diameter of the hole is the limit.
When the thickness of the base material is reduced, the rigidity of the drawing spring 12b is weak.
And the aperture heat 12b warps due to the heat of light.
I will. Also, if you drill holes beyond the limit, the diameter of holes 42 will vary
It becomes. Therefore, the rigidity is high, the heat is strong, and the light distribution is high.
An aperture that can reduce the amount of light to the limit without loss
In the spring 12b, as shown in FIG.
The base material is a three-layer structure in which a copper layer 45 is sandwiched between two nickel layers 46
It has a structure. A hole 42 is made in the base material of the drawing spring 12b.
First, only the outer nickel layers 46 are obtained.
Corrosion with a diameter larger than the diameter of the hole 44
Hole diameter determined by a solvent that corrodes only the copper layer 45
Open 4. This method reduces the thickness of the drawing spring 12b itself.
Copper that is smaller than the thickness of the drawing spring 12b
A hole 42 having a diameter equivalent to the thickness of the layer 45 may be formed.
High rigidity, high heat resistance and impaired light distribution
Instead, the light amount can be reduced to the limit. Next, an endoscope of the embodiment constructed as described above.
The operation of the mirror device will be described. In FIG. 1, after power-on, the operator
When the light control set SW is pressed for setting, the CPU 14
A predetermined value for determining the gain of the dimming circuit with respect to the position
Start the calculation. The changeover switch 17 is connected to the CPU 14
Is selected as an input signal. The CPU 14
The output of the oscillometer 13 changes step by step at a fixed amount.
Output to the aperture driving unit 18 as described above. Specifically, the CPU 14 controls the potentiometer
Monitor the output of the potentiometer 13
However, the squeezing spring 12 stairs at regular intervals in the direction from full opening to closing.
Of a counter that also changes in steps,
CP so that the value matches the output of potentiometer 13
It is controlled by U14. In this way, the diaphragm spring 12 is
The output signal of the DC conversion circuit 6 at each position.
The CPU 14 inputs the bell. Whether the relationship between the aperture position and the aperture amount in FIG.
DC at each position during the step operation of the aperture spring 12
The output signal level Vn of the circuit 6 and one step of the current aperture position
Signal level Vn-1 of the DC conversion circuit 6 at the position before the
Difference signal Vn-1-Vn, and the aperture spring 12 is fully open
The ratio with the output level Vmax of the DC conversion circuit 6 at the time is obtained.
The output signal level of the DC conversion circuit 6 at each aperture position is
The output signal level of the DC conversion circuit 6 at the position one step before the bell.
The difference between the bells (Vn-1-Vn) is used to convert the DC circuit 6 when fully open.
, And multiply by the constant A. This value
That is, the aperture ratio shown in FIG.
3 with an address signal corresponding to the output signal of the external memory 15
Write to. Until the diaphragm spring 12 is fully closed,
When the processing is performed, the changeover control output of the CPU 14
Changes the output of the phase correction circuit 10
Select From now on, the same as a normal automatic light control circuit
It is. That is, as shown in FIG.
The proportional output signal of the solid-state imaging device 4 is passed through the preamplifier 5
Then, it is integrated by the DC conversion circuit 6. The output of the DC conversion circuit 6 is
The difference is compared with the output of the reference signal generation circuit 7 by the comparison circuit 8.
Output according to. The output of the reference signal generation circuit 7 is operated
Is proportional to the dimming level set by the user. The output of the comparison circuit 8 is increased by GCA8.
As shown in Fig. 14, the amplification is normal auto dimming
Unlike the circuit, the output of the potentiometer 13 is not constant.
It changes according to power. In the initial operation, the CPU 14 calculates
Of the correction value obtained in the external memory 15
Data at the address corresponding to the output value of
The switching signal generation circuit 16 has an amplification degree corresponding to the correction value.
So as to output a gain switching signal to the GCA 9. The differential signal amplified by GCA 9 is
The phase is corrected by the positive circuit 10 and the changeover switch 17
Input to the diaphragm spring driving unit 18 and the output of the comparison circuit 8 is small.
The diaphragm spring 12 is driven in the direction to decrease. Therefore, the operator can externally use the storage means as storage means.
Is instructed to be written into the external memory 15,
The CPU 14 controls the aperture spring 12 at a predetermined interval.
Signal and output a signal proportional to the illuminance of the subject at that time.
Input sequentially, and subtract the difference between adjacent signals of the sequentially input signal.
Then, a predetermined operation is performed on the difference value, and the external memory 15
Write the aperture position or opening of the aperture spring 12 as an address.
Get in. Writing data for all throttle positions or opening degrees
Is completed, writing is prohibited and the aperture position or
Reads the data according to the opening and uses it as a response control means
Phase correction by the phase correction circuit 10 of FIG.
The combination of the system is controlled by controlling the driving unit 18.
Even if the setting is changed, the operator must
Calculates and sets the optimal response automatically with
Even in such combinations, hunting is suppressed and responsiveness is improved.
Be improved. As described above, in this embodiment, the light control set is performed.
By adjusting the aperture at the stop position in the total system,
Is calculated, a correction value corresponding to the value is calculated and stored,
Loop gay according to the aperture position at any time during automatic dimming operation
Camera compensation, so you can
Which camera control unit of the roll unit
Always appropriate aperture without hunting even when combined
Control can be performed. Next, a second embodiment of the present invention will be described. FIG.
5 and 16 relate to a second embodiment of the present invention, and FIG.
Endoscope provided with a light source device according to a second embodiment of the light control circuit
FIG. 16 is a configuration diagram showing a configuration of the electronic endoscope of FIG.
FIG. 4 is an explanatory diagram illustrating an adapter connectable to a distal end. No.
The second embodiment is almost the same as the first embodiment.
Only the same components will be described, and the same components will be denoted by the same reference numerals, and description thereof will be omitted.
Abbreviate. The light source device 3 according to the second embodiment has a panel
According to the brightness that can be set to any brightness by
A reference signal generating circuit 7 for outputting a signal;
A / D converter that inputs output signals and converts them to digital signals
A converter 52, an output of the A / D converter 52,
The difference is output by comparing with the output signal of the reference signal generation circuit 7.
A comparison circuit 8 and an output signal of the comparison circuit 8
A multiplier 53 that performs multiplication with the control signal of
A phase correction circuit 10 for correcting the
A D / A converter 54 for converting the output to analog, and an aperture
A half mirror 49 disposed on the exit side of the spring 12;
Light receiving element 5 arranged in the reflection direction of half mirror 49
0, the output of the DC conversion circuit 6 and the potentiometer
13 and the output of the light receiving element 50
A CPU 14 for performing calculations and before being connected to the CPU 14
Address signal corresponding to the output of potentiometer 13
External memory for storing the operation data of the CPU 14 according to the
Memory 15 and the DC conversion circuit connected to the CPU 14
6 according to an address signal corresponding to the output of the CPU 1.
4 and an external memory 51 for storing the operation data.
Is done. Other configurations are the same as those of the first embodiment. The operation of this embodiment will be described. After turning on the power, the operator adjusts the light for initial setting.
When the set SW is pressed, the half mirror 49 is placed in the exit optical path.
The CPU 14 controls the gain of the light control circuit with respect to the aperture position.
A predetermined calculation for obtaining the value is started. Also switch
Switch 17 keeps CPU 1 until the operation of CPU 14 is completed.
4 is selected as an input signal. The CPU 14
The output of the tension meter 13 changes step by step at a fixed amount.
Output to the aperture driving unit 18 as described above. More specifically, the potentiometer
Monitor the output of potentiometer 13
The force is applied to the floor at regular intervals in the
A counter that also steps like a step
And the output of potentiometer 13 match C
Suppressed by PU14. In this way, the diaphragm spring 12 is moved stepwise.
And the output signal level of the DC conversion circuit 6 at each position.
CPU 14 inputs the output signal level of
You. CPU 14 is a light receiving element when aperture spring 12 is fully open.
Steps of aperture spring 12 for 50 output signal levels
Between the output signal levels of the light receiving element 50 at each position during the
Calculate the ratio to the difference between
Find a value proportional to the gain. Each step during the step operation of the diaphragm spring 12 is described.
From the output signal of the DC conversion circuit 6 and the output of the
The value corresponding to the gain of CCU2 for the output light
You. The CPU 14 controls the light receiving element 50 at each aperture position.
Output signal level and photodetector one step before current aperture position
The difference from the output signal level of the slave 20 is obtained,
Divided by the output signal level of the light receiving element 50 at the open position,
The value corresponding to the output signal of potentiometer 13 is
Writing to the external memory 15 by a dress signal. The CPU 14 determines the step of the aperture spring 12
During operation, the output signals of the light receiving element 50 and the DC conversion circuit 6 are input.
And the direct current with the light receiving element 20 one step before the current aperture position.
From the output signal of the converting circuit 6, the light receiving element 5 at the current aperture position is
0 and the output of the light receiving element 50 one step before.
Difference and the output of the DC conversion circuit 6 at the current aperture position and one step.
The difference from the output of the DC conversion circuit 6 at the time before
The difference signal of the road 6 is divided by the difference signal of the light receiving signal 50. This value
With an address signal corresponding to the output signal of the DC conversion circuit 6
Write to the external memory 51. Until the diaphragm spring 12 is fully closed,
Process, the output of the changeover switch control of the CPU 14
The switch 17 changes the output of the phase correction circuit 10
select. Also, the half mirror 49 moves out of the optical path.
You. From now on, the same as a normal automatic light control circuit
It is. Output of the solid-state imaging device 4 in proportion to the amount of light of the subject
The signal is integrated by the DC conversion circuit 6 via the preamplifier 5
You. The output of the DC conversion circuit 6 is used as a reference signal generation time by the comparison circuit 8.
The output is compared with the output of the road 7 and output according to the difference. Reference signal
The output of the generation circuit 7 is compared with the dimming level set by the operator.
For example. The output of the comparison circuit 8 is supplied to the multiplier 53 by the CPU 1.
4 is multiplied by the output. The CPU 14 performs in the initial operation.
At the aperture position calculated and stored in the external memory 15.
Set the value corresponding to the gain of the aperture spring 12 to a potentiometer
13 is read at the address corresponding to the output value. In addition, external
The gain of CCU2 according to the output light stored in the memory 51
The corresponding value is stored in an address corresponding to the output value of the DC conversion circuit 6.
Read with. Read from external memory 15 and external memory 51
The CPU 14 multiplies the output data and calculates the reciprocal.
And multiply the reference value by the reciprocal to obtain the multiplier 53 as a multiplier.
Output. Multiplier 53 multiplies the data by CPU 14
The obtained difference signal is phase-corrected by the phase correction circuit 10 and D /
After converting to an analog signal by the A converter 54, the switching
Input to aperture driving unit 18 via switch 17 and compare
The diaphragm spring 12 is driven so that the output of the circuit 8 becomes smaller.
You. As described above, in this embodiment, the light control set is performed.
The gain of the diaphragm spring at the diaphragm spring position,
The output signal of the camera control unit, that is, the solid-state image sensor
Of the camera control unit according to the amount of light
Find the gain, calculate the correction value according to that value, and store it
Aperture stop position and solid-state imaging at any time during automatic dimming operation
Perform loop gain correction according to the amount of incident light on the element
Can be connected to multiple camera control units.
When combined with a camera control unit,
It is possible to always perform proper aperture control without causing ching etc.
Wear. In addition, as shown in FIG.
Endoscope with cap-shaped adapter 61 painted with paint
If you set the light control over the top of
Output of CCU2 saturates during operation in loop operation
And a calculation with good reproducibility can be performed. In addition, this method
If used, the white balance is set at the same time as the light control set.
I can. Next, a third embodiment will be described. FIG.
20 to FIG. 20 relate to the third embodiment, and FIG.
FIG. 18 is a configuration diagram showing a configuration of a road, and FIG. 18 is a phase correction circuit of FIG.
Flowchart for explaining the operation of the calculation CPU of FIG.
9 shows a configuration of a modification of the phase correction circuit of FIG.
FIG. 20 and FIG. 20 show the operation of the operation CPU of the phase correction circuit of FIG.
It is a flowchart explaining use. In the third embodiment,
Only the configuration of the phase correction circuit is different from that of the second embodiment.
Since they are the same, only different configurations will be described. As shown in FIG. 17, the phase correction of this embodiment
The circuit 10A receives the difference signal data from the multiplier 53.
The PIO 10a for powering is provided via the data bus 10b.
Connected to the CPU 10d dedicated to calculation. In addition,
The data bus 10b has a dedicated CPU 10d for operation and a control
ROM 10h storing the program, differential signal data
For outputting operation data obtained by correcting the phase to D / A
The IOs 10c are respectively connected. Also, calculation CP
Chip select according to address data from U10d
The decoder 10e that generates the signal 10g is connected to an arithmetic CPU
10d and the ROM 10h via the address bus 10f.
It is connected. Although not shown, for calculation
A control bar for transmitting a control signal output from the CPU 10d.
Connected to PIOs 10a, 10c and ROM 10e, respectively.
Has been continued. Next, the operation will be described. Power on
Then, the operation CPU 10d reads the control program from the ROM 10h.
Load the program and initialize the PIOs 10a and 10c
After that, the arithmetic processing is started. Diagram of the contents of this arithmetic processing
5 is shown in the follow chart. First, in step S1, P
Difference signal output from IO 10a by multiplier 53
Capture data DIN. Next, the loop characteristics of the control system
To optimize, based on the size of the difference signal data
In step S2, the correction gain G is supplemented in step S3.
The positive phase a is calculated. Based on these calculated data,
The difference signal data input in step S4 is corrected, and PIO1
Output to D / A via 0c. Therefore, in the third embodiment, the difference signal is corrected.
Correction factor for the hardware
And the versatility can be increased. Furthermore, one
Of the difference signal for the two hardware correction factors.
Multiple function data tables according to the optimization area
This can increase the accuracy of the control. A modification of the phase correction circuit having the configuration shown in FIG.
As an example, as shown in FIG.
Data corresponding to the dimming level set by the operator.
Phase correction circuit 1 having a PIO 10i
It may be 0B. Operation of the phase correction circuit 10B
Is almost the same as the phase correction circuit 10A of FIG.
As shown in the flowchart of FIG.
1 and output by the multiplier 53 from the PIO 10a
After fetching the difference signal data DIN, step S12 is performed.
To capture the reference signal data. Next, the loop of the control system
In order to optimize the characteristics,
Then, in step S13, the correction gain G is calculated in step S13.
At 14, the correction phase a is calculated. Based on these calculated data
The difference signal data input in step S15
Then, the data is output to the D / A via the PIO 10c. That is,
The dimming level reference value is also taken into account when calculating the correction coefficient.
are doing. In this modification, only the magnitude of the difference signal is used.
The dimming level value set by the operator is not
The third correction by the phase correction circuit of FIG.
In addition to the effects of the embodiment, it was adapted to more detailed use conditions
Control becomes possible. In each of the above embodiments, the adjustment is performed using an electronic endoscope.
The light source device as a dimming circuit that performs light has been described.
However, not limited to this, an external camera is attached to the optical endoscope.
A similar effect can be obtained with a girder configuration. By the way, an endoscope for observing the inside of a cavity (hereinafter referred to as an endoscope).
The lower part is called a scope, and a fixed image sensor (hereinafter
(Referred to below as CCD) on electronic scopes and eyepieces
Fiber Scope, etc. that can directly connect a camera for shooting
is there. These scopes are used to
To have an electrical connection to the detachable part that connects to the light source device
Has contacts. Also, the light source device has the scope connection described above.
The contact spring for contacting the point and maintaining electrical connection
It is provided in the loop holding unit. However, the attachment / detachment part of the scope and the light source device
In order to make it detachable between the cope holding part,
The scope is connected to the light source device and used
The contact spring deforms and wears
Deterioration due to wear, etc.
Cause. This allows the video signal of the electronic endoscope
Is disturbed or the camera cannot shoot.
It is hard to use. Therefore, as shown in FIG.
In the source device 103, the detachable portion 101 of the scope is
Scope that detects that it has been securely inserted into the loop holder
A connection fixing means 105 and a switch for fixing a detachable portion of the scope.
The scope fixing means 104 and the scope connection detecting means 1
05 by means of the detection signal from the
4 fixes the detachable part 101 of the scope with a predetermined strength.
And a fixed scope control means 106 for controlling the scope. More specifically, as shown in FIG.
A detachable switch between the scope holding units 102 and 103
As the light guide portion 101a of the co-op is inserted,
The detection rod 105a is moved by the light guide portion 101a.
When the scope is pushed down and the scope is securely connected,
Become like This detection rod 105a reflects light such as black.
It is colored with a color that is difficult to
It is exposed. This reflecting surface 105b has a reliable scope.
Where the photoreflector 105c operates when connected to
It is provided in the place. This photo reflector 105c is
Driven by the scope connection detecting means 105,
Scope connection detection when the photo reflector 105c operates
A detection signal is sent from the means 105 and the scope is fixed.
Means 106 receives this detection signal. At this time the scope
The fixed control means 106 controls the oil chamber 1 by the hydraulic pump 119.
Control is performed so that the pressure in 21 is maintained at a predetermined value. Ta
The oil of the ink 120 is sent to the oil chamber 121 through the pump 119.
When pressed, the pressing pad 104a becomes the fixed pad 104b.
Extruded towards. The springs 105d and 104d
Move the detection rod 105a and the pressing pad 104a to their original positions.
Generates restoring force to return. In such a light source device, first, a scope
To connect the light guide device to the light source device.
Is inserted between the scope holding units 102 and 103. this
The pressing pad 104a is inserted into the light guide portion 101a.
As it is raised to a position where it does not interfere with entry,
The guide portion 101a contacts the detection rod 105a from a certain position.
Or push down the detection rod 105a. And surely
When the scope is connected, the reflection surface 10 of the detection rod 105a is
5b brings the photoreflector 105c into the operating state.
You. Thereby, the detection signal from the scope connection detecting means 105 is output.
Is sent to the scope fixed control means 106 and the pump 1
19 starts working. From this point the scope fixed control hand
The stage 106 monitors the pressure in the oil chamber 121 and determines a predetermined pressure.
Continue pressurizing until. After reaching the specified value,
Control to maintain state. In the above pressurization process
The pressing pad 104a fixes the light guide portion 101a.
Move toward fixed pad 104b and press
You. Then, the light guide unit 101a is pressed with a constant pressure.
Keep going. As a result, the scope has no rattling
Will be held in a state. When the use of the scope is completed,
Pressing the unlock switch (not shown)
The loop fixing control means 106 controls the pressure in the oil chamber 121
Return to the state before the connection, and press the pad 104a to the initial position.
To return to the position and exit the scope. Therefore, the light guide portion 101a is
In order to secure it without any keys,
Of electrical contacts due to stress such as pulling or kinking
Wear and detachment can be eliminated. Further, a light source device for an endoscope as shown in FIG.
The scope attachment / detachment unit 101 is securely
Scope connection detecting means 1 for detecting the actual insertion
05 and the contact spring is pressed against the contact 131 of the scope.
Contact spring pressing means 132 and the scope connection detecting means
The contact spring pressing means 13 according to the detection signal from
2 controls the contact spring so as to press the contact spring with a predetermined pressure.
Point spring pressing control means 133 is provided. More specifically, as shown in FIG.
A detachable switch between the scope holding units 102 and 103
As the light guide portion 101a of the co-op is inserted,
The detection rod 105a is moved by the light guide portion 101a.
When pressed down and the scope is securely connected,
Become like This detection rod 105a reflects light such as black.
It is colored with a color that is difficult to
It is exposed. This reflecting surface 105b has a reliable scope.
Where the photoreflector 105c operates when connected to
It is provided in the place. This photo reflector 105c is
Driven by the scope connection detecting means 105,
Scope connection detection when the photo reflector 105c operates
The detection signal is sent from the means 105, and the contact spring pressing control is performed.
Means 133 receives this detection signal. At this time, the contact spring
The pressing control means 133 controls the hydraulic pump to control the pressure in the oil chamber 121.
Control is performed so that the force is maintained at a predetermined value. Tank 120
Is sent to the oil chamber 121 through the pump 119,
The pressing rod 132a is pressed toward the contact pin 131 of the scope.
Be sent out. The springs 105d and 132b are respectively detected
A return for returning the rod 105a and the pressing rod 132a to their original positions.
Generates original force. In such a light source device, first, a scope
To connect the light guide device to the light source device.
Is inserted between the scope holding units 102 and 103. this
When the pressing rod 132a and the contact spring 132c are
31 has risen to a position where it does not hinder insertion. Insertion
The inserted light guide unit 101a is detected from a certain position.
Hits the rod 105a and starts pushing down the detection rod 105a
You. When the scope is securely connected, the detection rod 10
The photoreflector 105c is formed by the reflecting surface 105b of 5a.
Becomes operational. Thereby, the scope connection detecting means 1
From 05, a detection signal is sent to the contact spring pressing control means 133.
Then, the pump 119 starts operating. From this point of contact
The spring pressing control means 133 monitors the pressure in the oil chamber 121.
Then, pressurization is continued until a predetermined pressure is reached. To the specified value
After that, control is performed to maintain that state. The above
During the pressure process, the pressing rod 132a is
To the contact pin 131 and press it further.
You. After that, keep pressing the contact spring 132c with a constant pressure
You. As a result, the contact spring 132c is always
The state of contact with 131 is maintained. When the use of the scope is completed,
Pressing the release switch (not shown)
The spring pressing control means 133 controls the pressure in the oil chamber 121
Return to the state before connection, and move the pressing rod 132a to the initial position.
Return, do not contact the contact spring 132c and the contact pin 131
State. Therefore, even if the scope is loose, the contact pins
Generated during use to keep the contact pressure between
Electricity caused by stress such as pulling or kinking of the scope
That is, it is possible to eliminate poor contact at the contact portion. That is, in the light source device shown in FIGS.
Of the scope created to make the scope detachable
Electricity generated due to rattling of the attachment / detachment part and the scope holding part
Since the wear and detachment of the air contact part can be suppressed, the contact
Eliminates poor contact in the unit, and disrupts the video signal of the electronic endoscope
In addition, it is possible to eliminate defective photographing of the photographing camera. [0069] [0070] As described above, the dimming circuit of the present invention can be used.
According to, ShootingCombinations of image means and light source means are limited
No hunting occurs without adjustment, smooth operation
There is an effect that a dimming circuit excellent in response can be realized.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration diagram showing a configuration of an endoscope device including a light source device as a first embodiment of a dimming circuit. FIG. 2 is an external view showing the external appearance of the light source device of FIG. FIG. 3 is an enlarged view of a duct main body of the light source device of FIG. 2; FIG. 4 is an enlarged view of a modification of the duct main body of the light source device of FIG. 2; FIG. 5 is an enlarged view of a thin spring and a projection of a housing in FIG. 4; FIG. 6 is a configuration diagram showing a configuration of an optical system of illumination light from the lamp in FIG. 1; FIG. 7 is a configuration diagram showing a configuration of an example of a diaphragm spring used in the optical system of FIG. 6; FIG. 8 is an explanatory view illustrating the structure of a light-transmitting hole of the stop spring in FIG. 7; FIG. 9 is a configuration diagram showing a configuration of a first modification of a diaphragm spring used in the optical system of FIG. 6; FIG. 10 is a configuration diagram showing a configuration of a second modification of the diaphragm spring used in the optical system of FIG. 6; FIG. 11 is a sectional view showing a detailed configuration of a second modification of the diaphragm spring of FIG. 10; 12 is a characteristic diagram showing a relationship between a stop position of a stop splash, a stop amount, and a stop ratio by the light source device of FIG. FIG. 13 is a characteristic diagram showing characteristics of an output of the CCD with respect to incident light of the electronic endoscope in FIG. 1; FIG. 14 is an explanatory diagram illustrating correction of a dimming loop gain by the CPU of the light source device of FIG. 1; FIG. 15 is a configuration diagram illustrating a configuration of an endoscope apparatus including a light source device according to a second embodiment of the light control circuit. FIG. 16 is an explanatory diagram illustrating an adapter that can be connected to the distal end of the electronic endoscope in FIG. FIG. 17 is a configuration diagram illustrating a configuration of a phase correction circuit of a dimming circuit according to a third embodiment. FIG. 18 is a flowchart for explaining the operation of the calculation CPU of the phase correction circuit in FIG. 17; FIG. 19 is a configuration diagram showing a configuration of a modification of the phase correction circuit of FIG. 17; FIG. 20 is a flowchart illustrating the operation of the calculation CPU of the phase correction circuit in FIG. 19; FIG. 21 is a configuration diagram showing a conceptual configuration of a light source device in which contact failure of an electric contact portion is unlikely to occur. FIG. 22 is a configuration diagram showing a specific configuration of the light source device of FIG. 21; FIG. 23 is a configuration diagram showing a configuration of a modification of the light source device of FIG. 21. FIG. 24 is a configuration diagram showing a specific configuration of the light source device of FIG. 23; [Description of Signs] 1 ... Electronic endoscope 2 ... CCU 3 ... Light source device 4a ... Light guide 4b ... Solid-state imaging device 5 ... Preamplifier 6 ... DC conversion circuit 7 ... Reference signal generation circuit 8 ... Comparison circuit 9 ... GCA 10 ... Phase correction circuit 11 lamp 12 aperture stop 13 potentiometer 14 CPU 15 external memory 16 gain switching signal generation circuit 17 switch

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masanobu Kotabashi 2-43-2 Hatagaya, Shibuya-ku, Tokyo O-limpus Optical Industry Co., Ltd. (72) Inventor: Tsuguhisa Sasai 2-43-2 Hatagaya, Shibuya-ku, Tokyo O-Limpus Optical Industry Co., Ltd. (72) Inventor Keiji Handa 2-43-2 Hatagaya, Shibuya-ku, Tokyo O-Limpus Optical Industry Co., Ltd. (56) References JP-A-6-285019 (JP, A) 60-53917 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04N 5/225-5/257 H04N 7/18 A61B 1/04

Claims (1)

(57) Claims 1. An illumination light supply means for supplying illumination light for illuminating a subject, and an illumination light supply means inserted into and removed from an optical path between the subject and the illumination light supply means.
Te, a throttle means for limiting the illumination light, light quantity detecting means for detecting the intensity of the returning light from the front Symbol subject supplied the illumination light by the illumination light supplying means, said a predetermined response The diaphragm unit is driven, and the light amount of the return light detected by the light amount detection unit and a predetermined reference
A light amount control unit that controls the light amount of the illumination light so that a difference from the light amount is small ; and an aperture unit based on an input of an execution operation from outside.
Over the entire range of the light quantity limit of the illumination light,
Calculating means for calculating a correction value for correcting the responsiveness of the light amount control means in accordance with the rate of limiting light, and correction value storing means for storing the correction value calculated by the calculating means. Features a dimming circuit.