JPH01213615A - Electronic endoscope device - Google Patents

Abstract

PURPOSE:To automatically perform appropriate dimming when the number of picture element in an image pickup means is different by switching a photometric range according to the characteristic of the image pickup means using plural solid-state image pickup elements whose number of picture elements is different and generating a dimming signal to said image pickup means. CONSTITUTION:A picture signal photoelectrically converted in the solid state image pickup element SID 11 is inputted in a photometric range switching circuit 12. A discrimination signal output circuit 13 is provided in a video converter which is externally mounted to an electronic endoscope and the circuit 13 transmits the kind of the SID 11 which is inputted in the discrimination circuit 14 in a signal processor and connected after the discrimination with the endoscope is performed and the photometric range to a timing control circuit 15, which transmits the kind of the SID 11 and a photometric range signal in accordance with the photometric range to the photometric range switching circuit 12 so as to switch the photometric range. Thus, when the electronic endoscope whose number of picture element is different is connected, it can be automatically set in a dimming level fitted to the SID of said number of picture elements.

Description

[Detailed Description of the Invention] [Industrial Application Field] [Prior Art] In recent years, electronic endoscopes with a built-in solid-state image sensor in the tip of the endoscope and optical endoscopes with an image guide have been developed. An endoscope with an external video converter (this also falls under the category of electronic endoscope), which is attachable and has a built-in video converter with a built-in solid-state image sensor that converts the observed image of the image guide into an image signal. ) became widely used.

For example, Japanese Patent Laid-Open No. 62-21140 discloses a conventional example in which the type of endoscope is determined and settings such as whether to perform image reversal or whether to form a mask are automatically performed.

By the way, many types of optical endoscopes are used, from small diameter ones to large diameter ones, depending on the target area. Therefore, even in electronic endoscopes, solid-state image sensors with different numbers of pixels are used. There has arisen a need to be able to use it in a variety of things with

[Problems to be Solved by the Invention] In the above conventional example, even if the type of endoscope is determined, the solid-state image sensor used in the endoscope is limited to one type, and endoscopes with different numbers of pixels are used. The mirror wasn't something I could deal with.

In addition, one endoscope can be connected to a video converter that can be connected to various electronic endoscopes with solid-state image sensors with different numbers of pixels, or endoscopes with various types of image guides from small to large diameters. Equipment (i.e. signal processing system and light source means)
However, since there is no switching mechanism in the photometry circuit, the dimming level may change depending on the solid-state image sensor. For example, as shown in Fig. 16, among CCDs 1a, Ib, and 1c that can be used with three different numbers of pixels, if the photometry range is set to match the CCD 1b with the middle number of pixels, the CCD with the smallest number of pixels
In 1c, the image pickup surface is only in the center of the photometry range, so no signal is output outside the image pickup surface, and the photometry level is output small (lower), making it impossible to adjust the light correctly. . Also, CC with the largest number of pixels
With D 1a, center-weighted metering is performed unintentionally, and the correct light control level cannot be obtained.

As described above, since the dimming level changes depending on the number of pixels, it is necessary to adjust the dimming level correction switch in order to set an appropriate dimming level.

The present invention has been made in view of the above-mentioned points, and does not require the operation of a light adjustment level correction switch, etc., and automatically adjusts the image pickup device to the appropriate level even in the case of an image pickup means having a solid-state image pickup device with a different number of pixels. An object of the present invention is to provide an electronic endoscope II device that can be set to a light control level.

[Means and effects for solving the problem] In FIG. 1 showing the basic configuration of the present invention, an image (video) signal photoelectrically converted by a solid-state image sensor (hereinafter abbreviated as SID) 11 is used for switching photometry ranges. It is input to the circuit 12.

A video converter externally attached to an electronic endoscope or an optical endoscope has a discrimination signal output circuit 13, and the discrimination signal output circuit 13 is input to a discrimination circuit 14 in a signal processing device, Endoscope discrimination (scope discrimination) is performed, and the type and photometry range of the connected 5ID11 are transmitted to the timing control circuit 15, and the timing control circuit 1
5 is configured to send a photometric range signal corresponding to the type and photometric range of the 5ID 11 to a photometric range switching circuit 12 to switch the photometric range.

Therefore, when an electronic endoscope or video converter with a different number of pixels is connected, the number of pixels is determined, the photometry range is switched according to the number of pixels, and the S of the determined number of pixels is
Automatically set the dimming level suitable for the ID.

[Example] Hereinafter, the present invention will be specifically explained with reference to the drawings.

2 to 10 relate to the first embodiment of the present invention, and FIG. 2 is an overall configuration diagram of the electronic endoscope device of the first embodiment,
FIG. 3 is a configuration diagram of an electronic endoscope, FIG. 4 is a configuration diagram of a light source device and a signal processing device, and FIG. 5 is an explanatory diagram showing that the COD used in the 11111 means has a different number of pixels. Fig. 6 is a circuit diagram showing the discrimination signal generation circuit and discrimination circuit, Fig. 7 is a circuit diagram of the timing control circuit, and Fig. 8 is a circuit diagram showing the discrimination signal generation circuit and discrimination circuit.
The figure is a circuit diagram of a photometric circuit, and FIGS. 9 and 10 are timing charts for explaining the operation of the first embodiment.

As shown in FIG. 2, the electronic endoscope device 21 of the first embodiment
For example, three electronic endoscopes 122a equipped with imaging means,
22b, 22c (22b and 22a have the same external shape,
22c shows only the connector portion. However, the outer diameter of the insertion portion and the number of pixels of the COD are limited. ) and the electronic endoscope 1122
i (ia, b.

C); a light source device 23 that supplies illumination light; a signal processing device 24 that performs signal processing for the electronic endoscope 22i; and a color monitor 25 that displays video signals output from the signal processing device 24 in color. It consists of

Each electronic endoscope 22i has an elongated insertion section 26 that can be inserted into a body cavity, etc., and a large operation section 27 is formed at the rear end of the insertion section 26. By rotating the angle knob 28, the insertion portion 26
A curved portion 29 formed near the tip of the can be bent vertically or horizontally.

A light guide 31 is inserted into the insertion portion 26 as shown in FIG. 3, and this light guide 31 is further inserted into a light guide cable 32 extending from the operating portion 27. A light source connector 33 is attached to the end of the light source 32 so that it can be connected to a connector receiver 34 of the light source device 23. By connecting this light source connector 33 to the light source connector receiver 34, illumination light is supplied to the input end face of the light guide 31, and this illumination light is transmitted and spread from the output end face roughly through the light distribution lens 35. and illuminates the subject side.

The object illuminated by the illumination light that has passed through the light distribution lens 35 is illuminated by the CCD 37 as an SID disposed on the focal plane of the objective lens 36 attached to the distal end of the insertion section 26.
i (if the It child endoscope is 21). This CCD 37i performs 8 photoelectric conversions. Therefore, as shown in FIG. 4, the COD drive circuit 3 in the signal processing bag M24
By applying a COD drive signal output from 8, the image signal is read out as an image signal. The COD drive signal and the image signal are transmitted by a signal cable, and a signal connector 41i is provided at the end of this signal cable so that it can be connected to a connector receiver 42 provided in the signal processing device 24.

As shown in FIG. 4, the light source device 23 includes a lamp 42 that generates white light, a concave mirror 43 that converts the white light of the lamp 42 into a parallel light beam, and emits it. A diaphragm device W144 that varies the light σ, a rotating color filter 45 that converts the illumination light focused by the diaphragm device 44 into component light of the three primary colors of red, green, and blue; Light guide 31 for component light
It has a condenser lens 46 that condenses light on the incident end face of the light source.

The rotating color filter 45 is provided with three fan-shaped openings on a rotating frame rotated by a motor 47, and these openings have color transmission filters 48R and 48G that transmit red, green, and blue wavelengths, respectively.

48B is installed, color transmission filter 48R948G
, 48B is formed of a light shielding member. Thus, transmission filters 48R, 48G, and 48B for each color are sequentially interposed in the optical path, such as red and green.

The subject is sequentially illuminated with blue color light, and images are taken by the CCD 37i under the illumination of each color light. Thus, during the light shielding period by the light shielding member, a COD drive signal is applied, each image is captured, and the image signals stored as charges are read out, and the image signals captured under illumination of each color light are subjected to signal processing. This enables frame-sequential color imaging.

By the way, the aperture device 44 is composed of an aperture blade 51 having a slit formed therein, and an aperture motor 52 attached to the base end of the aperture blade 51 and rotating in a direction perpendicular to the optical axis to reduce the amount of light passing through. The rotation of the aperture motor 52 is controlled by a drive signal from the aperture control circuit 53, and the amount of rotation (rotation angle) can be used to control the amount of light.

Incidentally, the image signal read out from the CCD 37i is input to the pre-processing circuit 55, and after being subjected to pre-processing such as carrier removal, is input to the AGC circuit 56.

The output signal of the AGC circuit 56 is input to an A/D comparator 57 and converted into a digital signal. This digital signal passes through a multiplexer 58 and changeover switches 598, 59B, and 590 to a pair of R and G signals, respectively.

Frame memory for B 61R, 62R: 61G.

62G: Stored sequentially in 61B and 62B. For example, an image signal captured under red illumination light is stored in one of the first and second frame memories 61R and 62R for R, for example 61
The other frame memory 62R is set to the read mode, and is input to the D/A converter 64A via the changeover switch 63A, and is converted into an analog R signal and output. Frame memory for other G 61G, 62G
The same applies to the B frame memories 618 and 62B.

In this way, a pair of frame memories 611 and 621 (1-R
, G, B), one frame memory 611
is used to store image data, the other frame memory 62I can be read out independently, and they are read out simultaneously (that is, the frame memories 62R, 6
2G and 62B image data are read out at the same time), are input to the D/A converter 64J via the changeover switch 63J (J=A, B, C), are D/A converted, and are sent to R2O, 8.
The three primary color signals are output from the RGB output terminal 65 to the monitor side and are also input to the matrix circuit 66.

The matrix circuit 66 converts the signal into a luminance signal Y and color difference signals R-Y, B-Y, which are further input to an NTSC encoder 67, converted into an NTSC composite video signal, and outputted from a composite output terminal 68.

By the way, in the first embodiment, three electronic endoscopes 22a,
22b and 22c, these electronic endoscopes 2
As shown in FIG. 5, 2a, 22b, and 22c are constituted by CCDs 37a, 37b, and 370 each having a different number of pixels.

In other words, the one using the CCD37a with the largest number of pixels (
For example, if the size is LIXL1), it is used for an electronic endoscope 122a having a large diameter insertion part, and a C with a medium number of pixels.
CD37b (its dimensions are e.g. L2XL2) is used for electronic endoscope!
3) is used for the electronic endoscope 1122c, which has the smallest diameter insertion section.

The signal connectors 41i of each of the electronic endoscopes 22a, 22b, and 22c can be connected to the connector receiver 42 of the signal processing device 24, and these electronic endoscopes 22a with different numbers of pixels
, 22b, and 22c to perform appropriate signal processing.

That is, as shown in FIG. 6, a discrimination signal generation circuit 71a is provided in, for example, the signal connector 41a of the electronic endoscope 122i (1-a in this case), and the -force signal processing device 24 side is provided with a discrimination signal generation circuit 71a. A discrimination circuit 72 is provided.

In the discrimination signal generation circuit 71a, for example, one contact of each of three switches 81, 82, 83 is commonly connected to one connector bin PO, and each of the other contacts is connected to one connector bin PO.
one connector pin P1. Connected to P2 and P3.

On the other hand, the discrimination circuit 72 selects the three bins P1, P2. P
The bottle receivers to which the common bottles PO are connected are each connected to a power source via a resistor R, and the bottle receivers to which the common bottle PO is connected are grounded.

Therefore, the three switches 81. S2. The combination of on and off of S3 is set in association with the number of pixels of cco37+. For example, depending on the CCDs 37a, 37b, and 37c, switches S1; 81. S2: Sl, 3
2.33 is turned on and the sieving switch is set to off. Therefore, the lines L1 . connected to these switches 81, 82, 83 and the resistor R. L2. L3 signal is “H”
II or “L” level, and these three binary signals become C
The discrimination signal corresponds to the number of pixels of the CD37i.

The signal line L1. L2. The determination signal L3 is input to the timing control circuit 73, and a readout sequence of the CCD 371 corresponding to the number of detected pixels is performed.

FIG. 7 shows a block diagram of a timing control signal that responds to the discrimination signal. The discrimination signal output from the discrimination circuit 72 is the upper address A1 of the vertical ROM 76 and the horizontal ROM 77.
It is input to 0 to A12. The vertical counter 78 is cleared at the beginning of the R exposure period (see FIG. 9) by a write start pulse 79 (hereinafter abbreviated as WSP), and thereafter continues to increment the address for one frame (one period) using the HD as a clock. The output of the vertical counter 78 is input to the lower address AO-A9 of the vertical ROM 76.

The output of the vertical ROM 76 is used as a control signal for each line (HD), and is used as an integral reset signal 81, R,
G, [3 sample and hold signals for each color field 82A
, 828.820, and other signals. The horizontal h counter 83 is cleared by the HD at the beginning of horizontal scanning, and thereafter continues to increment its output every 190 clocks using the CCD read clock as the counter clock (
IHD period) is input to lower addresses Δ0 to 80 of the horizontal ROM 77. This corresponds to switching the photometry range in the horizontal direction from this horizontal ROM 77, which will be described later.
(horizontal) photometry range switching signal 84 (one that causes an integration operation to be performed for a video signal period corresponding to the number of pixels in the horizontal direction of the CCD 37i), etc.

In this way, by switching the upper addresses of the horizontal and vertical ROMs 76 and 77 based on the output of the discriminating path 72, the photometry range corresponding to each of the CCDs 37i of the polymorphs is switched.

FIG. 8 shows a specific configuration of the photometry circuit 91 to which the output signal of the pre-processing circuit 55 in FIG. 4 is input.

The video signal from the CCD 37i is input to a clamp circuit 92 via a preprocessing circuit 55, where a DC component is reproduced and input to an analog switch 93.

This analog switch 93 is 0N1 for horizontal photometry.
0FF switch, as shown in Figure 10, CCD3
84a for 7a, 84b for CCD37b,
C0D37Cf7) @ conducts for the period shown in 84C,
It controls the input of the video signal to an integrating circuit consisting of a resistor 95 and a capacitor 96.

This analog switch 93 is connected to the horizontal ROM 77 described above.
On/off is controlled by a photometry range switching signal 84.

The integration circuit holds the integral value immediately before the analog switch 93 opens until the next readout period.

As described above, the photometry range in the horizontal direction is switched.

The analog switch 97 reads out each color field 11.
The capacitor 96 is made conductive by a reset signal 81 (as shown in FIG. 9) at the timing immediately before the capacitor 96, and the charge accumulated in the capacitor 96 is emptied. The integrated value of this capacitor 96 is output to the next stage through a buffer operational amplifier (hereinafter abbreviated as operational amplifier) 98. Immediately after the reading of each color field is completed, samples and holds are performed for each color. For example, immediately after the R field readout, the analog switch 101A becomes conductive in response to a sample hold signal at the timing indicated by reference numeral 82A in FIG.
Sample and hold is performed by a circuit consisting of 2A and 103A operational amplifier. Similarly, in the G field, the analog switch 101B conducts, the capacitor 102B and the operational amplifier 1
Sample and hold is performed by 03B. In field B, analog switch 101C conducts and capacitor 1
02G and is sampled and held by the operational amplifier 103C.

As described above, the photometry range in the vertical direction is switched.

The sampled and held dimming signals of each color field are weighted and mixed by an amplifier including an operational amplifier 105 and a resistor 106 through weighted resistors 104A to 104G, and a dimming signal as one frame is generated.
It is input to an aperture control circuit 53 shown in FIG.

The above resistors 104A and 1048.104G are R of the dimming signal.
, G, B component ratio is the component ratio R of the luminance signal Y of the NTSC signal.
: G : B = 0.3 : 0.6 : It is set to be approximately 0.1. In this way, it is possible to maintain a good dimming level even for CCDs 37i having different numbers of pixels.

Further, in this first embodiment, the AGC circuit 56 is
The signal passed through the C circuit 56 is input to the photometric circuit 105, and the output of this photometric circuit 105 is further passed through the AGCill11 circuit 106, and the gain of the AGCIW path 56 is controlled by the tc A G C control signal. .

The photometry circuit 105 has the same configuration as the photometry circuit 91 shown in FIG.
By controlling the gain of the C circuit 56, this AGC
The level of the video signal input to the A/D converter 57 via the circuit 56 is controlled so as to be an appropriate value even for CCDs 37i having different numbers of pixels. In this case, the AGC circuit 56 controls the AGC circuit 56 by adjusting the level proportional to the luminance signal.
Since the GC gain is adjusted to IIJIB, it is possible to prevent the gain from changing depending on the video signal for each color field that is input in time series for each color field, that is, to prevent the white balance from changing. Maintain at video signal level. Therefore, it is possible to maintain brightness and color tone suitable for endoscopic diagnosis. Incidentally, the timing control circuit 73 (or the discrimination circuit 72) controls the drive circuit 38 and the connected electronic endoscope 1122.
A drive signal capable of reading out the number of pixels of CCD 37i of i is output.

The operation of the first embodiment configured in this manner will be described below with reference to FIGS. 9 and 10.

As shown in FIG. 9, the rotating color filter 45 rotates in synchronization with the vertical synchronizing signal VD. Thus, at the beginning of the exposure period of each color field of the rotating color filter 45, the timing control circuit 73 outputs a write start pulse WSF' 79, resets the zero counter 78, and then uses the horizontal synchronization signal HD as a clock to perform address processing. is incremented every one frame. At the end of the exposure period of each color field, from the drive circuit 3B to the CC
A read drive signal is applied to D371, and the CCD
A video signal is output from the 37i. In this case CCD37
Immediately before applying the drive signal to i, the timing control circuit 73 outputs an integral value reset signal 81,
The analog switch 97 shown in FIG. 8 is turned on to empty the charge accumulated in the capacitor 94. The video signal output period of the video signal output from each CCD 37i differs depending on the number of pixels. That is, the CCD 37 with the largest number of pixels
The video signal in case a has a longer output tI interval than the video signal in case of CCDs 37b and 37c.

Immediately after reading out each color field, the video signal for each color field is transferred to the sample and hold circuit 103.
A, 1038.103C are sampled and held sequentially. In other words, the discrimination circuit 72 determines that the CCD 37 used in the electronic endoscope 11221 connected to the signal processing equipment 24
i is determined, and in accordance with this determination, the vertical ROM 76 outputs a sample hold signal 82A after reading in each color field.
.

82B, 82G output, analog switch 101A,
101B and 10IC are sequentially ONL and sample held. The R, G, and B color signals sampled for each color field are connected to resistors 104A, 1048.104
G, the operational amplifier 105 and the resistor 106, the luminance signal @
A dimming signal proportional to Y is generated and input to the aperture control circuit 53.

Note that, as shown in FIG. 10, reading from the CCD 37i in the horizontal direction is also performed using, for example, a clock synchronized with the horizontal synchronizing signal HD. In this case, the period of the video signal output from the CCD 37i differs depending on the number of pixels (in the horizontal direction) of the CCD 371, but depending on the output signal of the discrimination circuit 72, the horizontal ROM 77
outputs the photometry range switching signal 84, and turns on the switch 93 shown in FIG. 8 for a period corresponding to the video signal period as shown in FIG. 10, and turns it off for the other periods.

Aperture is activated by the above dimming signal! The 1ljifi circuit 52 is
The rotation angle of the aperture motor 52 is set to tlJIllt, and the amount of illumination light passing through the aperture blades 51 is automatically set to an appropriate level. In other words, automatic light adjustment will be performed.

Further, the AGC circuit 56 automatically maintains the video signal of the CCD 37i at an appropriate level even when the number of pixels of the CCD 37i differs. In this case, the gain control of the AGC circuit 56 is performed at a value proportional to the luminance level during one frame period. ! Therefore, even in a frame-sequential signal processing system in which R, G, and B video signals are input for each color field, it is desirable that there is no change in white balance or color tone, even when the number of pixels of the CCD 37i differs. It is held at the video signal level and output to the next stage. Therefore, even if the number of pixels of the CCD 37i differs, color display will be performed on the color monitor 25 with appropriate brightness.

FIG. 11 shows an electronic endoscope device 11 according to a second embodiment of the present invention.
1 is shown.

This electronic endoscope device 111 includes the electronic endoscope 22i.
Instead of (or together with the electronic endoscope 11221) the video converter 11 is attached to the eyepiece 113 of the fiberscope 1121.
41 is externally attached (attached) to the external video converter that allows the use of scope 1151 (first
Only one is shown in Figure 1. In other words, 1-a).

FIG. 12 shows the configuration of a scope 115a with an external video converter as an electronic endoscope.

In the fiber scope 112a, a light guide cable 117 extends from the operating section 116, and a light guide connector 11 is attached to the tip of the light guide cable 117.
8 is provided and can be connected to the connector receiver 34 of the light source device 23. Fiber scope 112 shown in FIG.
a is a CCD in the electronic endoscope 22a shown in FIG.
37i is replaced by an image guide 121, and the optical image transmitted by this image guide 121 is transmitted to the eyepiece 12.
2 so that it can be observed with the naked eye from the eyepiece section 113. Other components that are the same as those of the electronic scope 22a are given the same reference numerals.

As shown in FIG. 11, the video converter 114a has a built-in image means consisting of an imaging lens 124 and a CCD 125i as an SID disposed at a position where an image is formed by the imaging lens.

The video converter 114a sends the video signal photoelectrically converted by the CCD 125a via the signal cable 126,
The signal connector 127a attached to the end of the signal cable 126 can be connected to the signal connector receiver 42' of the signal processing device M24'. The signal connector 127a includes, for example, a discrimination signal generation circuit 128a shown in FIG. 13, and the -power signal processing circuit 24' includes:
A discrimination circuit 129 shown in this figure is provided.

In the discrimination signal generation circuit 128a, for example, a discrimination resistor Ra is connected to two connector bins Pi and P2. On the other hand, the determination circuit 129 of the signal processing device 24' determines that the bin receiver to which the connector bins Pi and P2 are connected is the constant current circuit 1.
31 and the ground, respectively. The constant current l output from this constant current circuit 131 is
The voltage Ra I of this resistor Ra is applied to each input terminal of one of the three comparators 131A, 131B, and 131G, and the constant voltage E1 . E2. Compared to E3.

These constant voltages E1. E2. E3 is, for example, El>E
2>E3, while CCD125 i
The resistance Ri (ia, 'o, -) set corresponding to, for example, El>Ra I>E2. E2>Rb I>E3
．． It is set so that E3>Rc1.

Therefore, as C0D22i, for example, C0 shown in FIG.
If it is equal to D22i, the CC with the largest number of pixels
In D125a, comparators 131A, 131B, 13
The output of 1G is H and L.

However, for C0D22i with a medium number of pixels, H9N, L,
C0D22i, which has the smallest number of pixels, is set to H2N and H. Therefore, these comparators 131
The number of pixels of the CCD 125i can be determined from the outputs of A to 131C.

This second embodiment has the same structure as the first embodiment in other respects, and its effects are also the same.

FIG. 14 shows a photometric circuit 91' which is the main part of a third embodiment of the present invention.

In the first embodiment shown in FIG.
The switching timing of the analog switches 93, 97, 101A to 101C shown in FIG. 91' is used. This photometry circuit 91' connects the gain setting resistor 106 of the operational amplifier 105 in the photometry U path 91 shown in FIG.
A multiplexer 131 that is switched according to the CCD 37i or 1251, and resistors 106a and 106b that are selected by this multiplexer 131.

···I have to.

The multiplexer 131 includes a discrimination circuit (for example, 72)
The switching is controlled by the output signal of.

According to this third embodiment, the CCD 371 or 125 has the same characteristics such as photoelectric conversion characteristics (sensitivity) but has a different number of pixels.
CCD is not limited to those that constitute CCD 1, but can also be used with CCDs that have different characteristics.
37i or 1251, the CCD3
Resistors 106a and 10 provided corresponding to 7i or 1251
If you select 6b,..., it is not just the number of pixels, but also the CO
By compensating for the differences in characteristics inherent to the COD, it is possible to generate a dimming signal suitable for the COD.

Note that the present invention is not limited to the one in which light is adjusted over the entire imaging surface of each COD, but as shown in FIG. It can also be applied to photometry.

In this case, for example, in the photometry circuit 91' shown in FIG. 14, the analog switches 93.101A to 101C may be turned on only during the video period corresponding to the photometry range 142.

Note that the present invention is not limited to the case of an electronic endoscope or a video converter equipped with a color imaging means of a frame-sequential method; It is also applicable to the case of simultaneous color Ill imaging means).

Furthermore, the present invention is not limited to providing a discrimination signal generation means on the electronic endoscope or video converter side, but also provides a pixel number detection means for automatically detecting the number of pixels of the connected COD on the signal processing system side. The photometry range may be switched using the output signal of this means. (This automatic pixel number detection means has been applied for in Japanese Patent Application No. 62-266059.

) In the above explanation, the dimming signal is generated according to the characteristics unique to the prisoner image element, such as the number of pixels of the solid-state image sensor and its sensitivity. Alternatively, the light control level may be set in consideration of the F number of the imaging lens system.

[Effects of the Invention] As described above, according to the present invention, it is possible to improve the image pickup means using a plurality of solid-state image pickup devices having different numbers of pixels. Since a dimming signal is generated by switching the photometric range in accordance with the characteristics of the am image means, it is possible to automatically perform appropriate dimming even when the number of pixels differs.

[Brief explanation of the drawing]

FIG. 1 is a conceptual configuration diagram of the present invention, FIGS. 2 to 10 relate to a first embodiment of the present invention, and FIG. 2 is an overall configuration diagram of an electronic endoscope device according to the first embodiment. , FIG. 3 is a configuration diagram of an electronic endoscope, FIG. 4 is a configuration diagram of a light source device and a signal processing device,
Fig. 5 is an explanatory diagram showing that the COD used in the m-image means has a different number of pixels, Fig. 6 is a circuit diagram showing the discrimination signal generation circuit and discrimination circuit, and Fig. 7 is the circuit of the timing control circuit. Figure 8 is the circuit diagram of the photometric circuit, Figure 9 is the circuit diagram of the photometric circuit.
10 and 10 are timing charts for explaining the operation of the first embodiment, and FIG. 11 shows the rest period of the second embodiment of the present invention.
12 is a configuration diagram of a fiber scope and a video converter, FIG. 13 is a circuit diagram showing a discrimination signal generation circuit and a discrimination circuit in the second embodiment, and FIG. 14 is a photometry diagram in the third embodiment of the present invention. A circuit diagram of the circuit, Fig. 15 is an explanatory diagram showing the photometry range when center-weighted photometry is performed, and Fig. 1
6 is an explanatory diagram showing solid-state image sensors having different numbers of pixels. 11... Solid-state image sensor (SID) 12... Photometric range switching circuit 13... Discrimination signal output circuit 14... Discrimination circuit 15... Timing control circuit 21... Electronic endoscope device 22a ...Electronic congratulations 11 23...Light source device 24.
...Signal processing device 25...Color monitor 37a
-= CCD 56...AGC circuit 71a...Discrimination signal generation circuit 72...Discrimination circuit 91.105...Photometry circuit 10G...AGC control circuit Fig. 1 Fig. 3 Fig. 5 Figure 8 Figure 10 Figure 12 Figure 13 / 129 Procedural City Official Book (Voluntary) 11. Display of incident Patent Application No. 40265 of 1988
2. Title of the invention Electronic type 8! Mirror device is the representative representative Satoshi Shimoyama Department 5. Date of amendment order (voluntary) 6. Subject of amendment ``Detailed explanation of the invention'' column of the specification, description In the 13th line to the 7th line of page 18 of the inner box, "...to be controlled...to be held..." has been corrected to "...to be controlled..." To do. , and color tone on page 18 of the statement, line 18.
Delete. , on the fourth line of page 22 of the statement, the phrase "...without any change..." has been changed to "...due to the change..."
・Corrected to ``.

Claims (1)

[Claims] An electronic endoscope apparatus comprising an electronic endoscope having an externally attached or built-in imaging means using a solid-state image sensor, a light source for illumination, and a signal processing means having an automatic gain control means, wherein the imaging means and an automatic light control means that automatically adjusts the amount of illumination light output from the light source based on the output signal of the determination means. Electronic endoscope device.