JP2001029313A - Endoscope device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain observation images of adequate brightness without depending upon the kinds of the endoscopes containing solid state image pickup elements. SOLUTION: The endoscope 2 arranged with a CCD 9 at the front end of an insertion part 6 is freely attachably and detachably connected to a processor 3, by which the information previously stored in a ROM 48 is transmitted to a control means 21 in the processor 3. This control means 21 controls the sensitivity of the CCD 9 according to the connected endoscope 2 by a CCD sensitivity control means 12 so that the observation images of the adequate brightness may be obtained without depending upon the kinds of the endoscopes 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an endoscope apparatus for imaging using a solid-state image sensor capable of controlling sensitivity.

[0002]

2. Description of the Related Art An endoscope apparatus for performing an endoscope inspection with an endoscope having a solid-state image pickup device includes an endoscope such as an electronic endoscope, a processor, a light source device, and a monitor. Is inserted into the body cavity, and the illumination light from the light source device illuminating the subject via the light guide built into the endoscope is photoelectrically transmitted by the solid-state imaging device arranged at the end of the endoscope. This is a device that processes a video signal obtained by conversion with a processor and displays the signal on a monitor.

[0003] For example, there is known a plane-sequential type endoscope apparatus for performing normal observation using illumination light in a visible region as disclosed in Japanese Patent Application Laid-Open No. 1-221135. Also, as disclosed in Japanese Patent Application Laid-Open No. 9-70384, a living tissue is irradiated with excitation light, and the fluorescent light emitted from the living body is observed, whereby an endoscope device for fluorescence diagnosis for finding early cancer or the like is used. Is also widely used.

The imaging device used in the internal mirror device for fluorescence diagnosis requires high sensitivity to observe weak fluorescence, and an imaging tube is mainly used. Further, Japanese Unexamined Patent Publication No.
Japanese Patent No. 252450 discloses a technique in which an overflow drain voltage of a solid-state imaging device is controlled in accordance with an output signal level of the solid-state imaging device, so that a portion that cannot be completely corrected by light amount control using a diaphragm can be imaged. .

[0005]

In the endoscope apparatus, various endoscopes are properly used depending on the diagnosis site and the method of diagnosis. An endoscope used for bronchial examination has a smaller diameter than an endoscope used for colon examination.

[0006] The diameter of the endoscope affects the number of light guides inside the endoscope, and appears as a difference in irradiation light amount. Also, the aperture value of the lens differs depending on the use of the endoscope. In particular, with an endoscope having a large aperture value, the amount of light may be insufficient when observing a subject located at a far point, resulting in a dark observation image.

These factors cause the range in which an appropriate amount of light necessary for imaging is obtained to differ greatly depending on the type of endoscope. On the other hand, in the endoscope device, in addition to the normal observation,
Diagnosis by special observation such as fluorescence observation is also possible.

However, since the fluorescence observation must capture very weak auto-fluorescence, the solid-state imaging device provided at the end of the endoscope needs a much higher sensitivity than the solid-state imaging device usually used for observation. Is done.

In view of the above, the present invention provides an endoscope apparatus that controls the sensitivity of a solid-state imaging device according to the type of endoscope and obtains an observation image with appropriate brightness regardless of the type of endoscope. The purpose is to do.

[0010]

SUMMARY OF THE INVENTION The present invention relates to U.S. Pat. S. Pa
t. No. 5,337,340 "Charge Mul
tipping Detector (CMD) sui
table for small pixel CCD
As shown in “image sensors”, by creating an electric field region with sufficient strength and colliding conduction electrons with atoms, the electrons are released from the valence band and the original conduction electrons collide. This technique focuses on a technique for increasing the charge by ionization and improving the sensitivity, and an endoscope having a solid-state imaging device with variable sensitivity, In an endoscope apparatus having a signal processing device that performs signal processing on an output signal and a light source device that irradiates illumination light to a subject, by providing a sensitivity control unit that controls sensitivity of the solid-state imaging device, Observed images with appropriate brightness can be obtained regardless of the type.

An externally applied sensitivity control pulse (CMD)
It also has a feature that the sensitivity can be freely controlled by the amplitude of the “gate pulse” and the number of pulses. By controlling the sensitivity, a high-sensitivity solid-state imaging device that does not generate noise due to multiplication and does not require cooling can be realized, so that an endoscope with good image quality and excellent insertability can be realized.

Further, the sensitivity control means is provided in a signal processing device, and the sensitivity of the solid-state imaging device is set according to the type of the endoscope or the characteristics of each solid-state imaging device. Observed images with appropriate brightness can be obtained regardless of the type of mirror or the characteristics of each solid-state imaging device.

In addition, the sensitivity control means controls the sensitivity of the solid-state imaging device in accordance with a signal from the designating means for designating the sensitivity of the solid-state imaging device, so that the type of endoscope or the solid-state imaging can be easily achieved. Observed images with appropriate brightness were obtained regardless of the characteristics of each element.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIGS. 1 to 6 relate to a first embodiment of the present invention, and FIG. 1 is a block diagram showing a schematic configuration of an endoscope apparatus according to the first embodiment. FIGS. 2, 3 and 4 are block diagrams showing configurations of pre-signal processing means, frame sequential signal synchronizing means and post-signal processing means constituting the signal processing means, and FIG. 4 shows various types used in the present embodiment. FIG. 5 shows an application of the endoscope, etc.
FIG. 6 shows an operation explanatory diagram.

As shown in FIG. 1, an endoscope apparatus 1 according to a first embodiment of the present invention is an electronic endoscope (hereinafter simply referred to as an endoscope for simplicity) having a built-in solid-state imaging device. Abbreviation) 2,
The endoscope 2 is detachably connected, a processor 3 having a signal processing device 4 and a frame sequential light source device 22 built-in, and a monitor connected to the processor 3 for displaying a video signal processed by the processor 3. And 5.

The endoscope 2 has an elongated insertion portion 6 inserted into a body cavity. A distal end portion 7 of the insertion portion 6 has an objective lens 8 for forming an image of a subject, and an At the image forming position, for example, a charge-coupled device (CCD) is used as a solid-state imaging device.
The CCD 9 is connected to a CCD driving means 11 and a CCD sensitivity control means 12 provided in a signal processing device 4 in the processor 3 via a signal line, and the CCD driving means 11 and the CCD sensitivity Exposure / read-out is controlled by the drive signal and the sensitivity control signal generated by the control means 12.

This CCD 9 is a U.S.A. S. Pat. No.
5,337,340 "ChargeMultiplyii
ng Detector (CMD) suite
for small pixel CCD image
As shown in "sensors", by creating an electric field region having sufficient strength and causing conduction electrons to collide with atoms, the electrons are released from the valence band and the original conduction electrons collide. This CCD is a CCD that multiplies the charge by this ionization and improves the sensitivity, and also receives an external control pulse (CM
It also has a feature that the sensitivity of the CCD can be freely controlled by the amplitude of Dgate pulse) and the number of pulses.

Therefore, since a high-sensitivity CCD can be realized without generating noise due to the sensitivity multiplication and without cooling, it is suitable for realizing an endoscope with good image quality and excellent insertability. The CCD 9 is connected to signal processing means 14 provided in the processor 3 via a buffer 13, and the subject image formed on the imaging surface of the CCD 9 by the objective lens 8 is converted into an electric signal by the CCD 9. The output is read, and the output is supplied to the signal processing means 14.

Further, the endoscope 2 is provided with a light guide 15 for transmitting illumination light, and an illumination lens 16 is disposed on the distal end side of the light guide 15. The illuminating light transmitted inside illuminates the subject via the illumination lens 16.

The signal processing means 14 includes a pre-signal processing means 17 for performing various signal processing of the output signal read by the CCD 9 and a plane-sequential signal for synchronizing the plane-sequential signals output from the pre-signal processing means 17. Signal synchronization means 18;
And post signal processing means 19 for performing various signal processing for outputting the output signal of the frame sequential signal synchronizing means 18 to the monitor 5 and the like. The output signal read from the CCD 9 is converted into a television signal. And output it to the monitor 5 or the like.

The CCD driving means 11 and the CCD
The sensitivity control means 12 and the signal processing means 14 are connected to a (first) control means 21, and control is performed by the control means 21.

The control means 21 controls a stop 23, a stop control means 24, and an RGB rotary filter control means 25 provided in a field sequential light source device 22 for supplying field sequential illumination light to the endoscope 2 (No. 1). 2) also connected to the control means 26, and in synchronization with the RGB rotation filter control means 25,
The CCD driving means 11 and the signal processing means 14 are controlled.

The surface-sequential light source device 22 includes a lamp 27 for generating illumination light, a condenser lens 28 for condensing a light beam of the illumination light on the rear end surface of the light guide 15,
An RGB rotation filter 29 inserted between the lamp 27 and the condenser lens 28 is provided.

This rotary filter 29 is rotatably connected to a rotary shaft of a motor 30,
By controlling the rotation at a predetermined speed via the rotation filter control means, the RGB surface sequential light is supplied to the rear end surface of the light guide 15.

The signal processing means 14 is configured, for example, as shown in FIG. The pre-signal processing means 17 includes:
The frame sequential signal output from the endoscope 2 is input.

In the pre-signal processing means 17, the CCD 9
Is converted to a digital signal by an A / D converter 34 via a CDS circuit 31, an LPF 32 and a clamp circuit 33. This digital signal is supplied to the photocoupler 35.
The signal a is isolated and transmitted from the patient circuit to the secondary circuit.

In the secondary circuit, a white balance correction circuit 36, a color tone adjustment circuit 37, and a gamma correction circuit 38 are provided. Enlargement is performed by zoom processing. The output signal of the enlarging circuit 39 is input to the frame sequential signal synchronizing means 18 via the contour emphasizing circuit 40.

The control means 21 outputs a control signal for controlling the operations of the white balance correction circuit 36, the color tone adjustment circuit 37, the enlargement circuit 39, and the contour emphasis circuit 40 in the secondary circuit, and serves as an isolation transmission means. Clamp circuit 33 in the patient circuit via photocoupler 35b
Output a control signal for controlling the operation of.

The RGB plane-sequential signal output from the pre-signal processing means 17 is a plane-sequential signal synchronizing means 1 shown in FIG.
8 are inputted to the synchronizing means 43a, 43b, 43c via the changeover switches 41, 42A, 42B.

The synchronizing means 43a, 43b, 43c
Has at least one screen of memory, and sequentially has R, G,
The frame-sequential signals input in the order of B are stored in memories for the respective colors, and the stored frame-sequential signals are simultaneously read out and output as synchronized signals.

As an example of the synchronizing means 43a, 43b, 43c, for example, as shown in FIG.
i (i = a, b, c) can be constituted by means having image memories 44a, 44b for at least two screens. Here, image writing and image reading of the image memories 44a and 44b are alternately switched to perform synchronization.

The synchronized output signals synchronized by the synchronizing means 43a, 43b and 43c are output to the still image memories 45a and 45 in the post signal processing means 19 for storing still images.
5b and 45c and the selector 46.

Synchronization means 43 via selector 46
Synchronized outputs of a, 43b, and 43c are supplied to the monitor 5 via a 75Ω driver 47 at the subsequent stage as a moving image. A still image memory 45 is connected to the other input terminal of the selector 36.
Outputs a, 45b, and 45c are connected.

Image writing and image reading of the still image memories 45a, 45b and 45c are controlled by the control means 21, and the control means 21 responds to a freeze command from the outside.
Controls the still image memories 45a, 45b, and 45c so as to store the image at the time when the freeze command is given, and provides the selector 46 with the synchronization means 43a, 4b.
3b, 43c output moving image signal and still image memory 45
Of the still image signals which are the output signals a, 45b and 45c, control is performed so that the still image signal is supplied to the monitor 5 via the 75Ω driver 47 at the subsequent stage.

The endoscope 2 has a built-in ROM 48 which stores information specific to the endoscope 2. When the endoscope 2 is connected to the processor 3, the information is transmitted to the signal processing device 4 inside the processor 3. Is transmitted to the control means 21 in the CCD 9
Is performed. That is, the ROM 48 forms a designating means for designating the sensitivity of the CCD 9. .

As shown in FIG. 4, in addition to the endoscope 2, various types of endoscopes 2I are provided in accordance with the region to be observed and the purpose of use.
(I = A, B, C) are prepared. However, in order to reduce the diameter, the number of light guides 15 is smaller than the endoscope 2 and the lens aperture value is smaller than the endoscope 2. There are an endoscope 2B that increases the depth of field by increasing the number of filters, and an endoscope 2C in which a filter 49 that transmits only the fluorescence of a living body for fluorescence observation is disposed in front of the CCD 9, and is detachably connected to the processor 3. It is possible.

FIG. 5 shows the characteristics of the endoscopes 2 and 2I, and information (for example, the sensitivity control pulse φ) corresponding to the characteristics.
Information including the number of CMD pulses) is stored in the ROM 48 in advance. The information in the ROM 48 provided in the endoscope 2 or 2I connected to the processor 3 is stored in the control unit 2
1 and the control means 21 controls the endoscopes 2 to 2 for normal observation.
B determines the sensitivity of the CCD 9 as a solid-state imaging device so that an appropriate exposure amount can be obtained.

Here, when the amount of light supplied from the light source device 22 to the rear end face of the light guide 15 is constant, even if the number of light guides and the f-number of the lens aperture are different, the CCD 9
The sensitivity control value of the CCD 9 is calculated such that the signal levels of the output signals are equal. When the number of light guides and the f-number of the lens aperture are different, information based on the difference is included.

For example, when the number of light guides is small, control is performed so that the sensitivity of the CCD 9 is higher than when the number of light guides is large.

In the endoscope 2C for fluorescence observation, information indicating that the endoscope is for fluorescence observation is sent, and the sensitivity setting value is set to a predetermined value. The control means 21 controls the CCD driving means 11 and the CCD sensitivity control means 12 based on the calculation result. FIG. 6 shows drive signals and sensitivity control signals output from the CCD drive means 11 and the CCD sensitivity control means 12.

FIG. 6 shows the exposure period / light-shield period (readout period) of the RGB rotation filter and the CCD 9 in that case.
Control pulse φCMD, vertical transfer pulse φI
The relationship between AG, horizontal transfer pulse φSR, and CCD output signal is shown.

The sensitivity of the CCD 9 can be controlled by either the number of pulses of φCMD or the pulse amplitude. Here, the number of pulses is adjusted to obtain a desired sensitivity. In this case, a sensitivity control pulse φCMD is output to the CCD 9 during a light-shielding period (reading period) after the exposure time, and the CCD 9
, The vertical transfer pulse φIAG and the horizontal transfer pulse φSR are output to the CCD 9 to obtain an output signal from the CCD 9.

For example, as shown in FIG. 5, the number of pulses of the sensitivity control pulse φCMD is changed with respect to the CCD 9 of the endoscope 2 or 2I connected according to the intended use, and the endoscope 2 or 2I is The required sensitivity can be easily obtained.

In FIG. 5, it is assumed that there is a 1% electron multiplication for each φCMD pulse in order to simplify the calculation.

In the endoscope 2C for fluorescence observation, a filter 49 having a characteristic of passing the wavelength of the fluorescence of the living body in the range of 480 nm to 600 nm is arranged on the front surface of the CCD 9. Only the weak fluorescence excited by the blue component (wavelength 400 nm to 500 nm) of the frame sequential light by the RGB rotation filter 29 is converted into a video signal by the CCD 9 set to have high sensitivity.

Synchronization means 43a, 43 in processor 3
b and 43c simultaneously store all the signals of only the blue component in memories for each color, and simultaneously read out the stored frame-sequential signals and output them as monochrome images.

This control is performed by the control means 21. The switching between the signal processing for normal observation and the signal processing for fluorescence observation described above is performed by the ROM 48 in the endoscopes 2 to 2C.
This is done based on information from.

As described above, according to the present embodiment, it is possible to obtain an observation image with appropriate brightness by controlling the sensitivity of the solid-state imaging device in accordance with the type of the endoscopes 2 and 2I to be connected. The endoscope device 1 which can be realized can be realized.

The information output from the ROM 48 may be a parameter such as a light distribution characteristic or an angle of view, or a correction value for individual variation in brightness. Of course, the sensitivity setting value of the CCD 9 itself may be transmitted to the processor 3.

In this embodiment, the information of the ROM 48 provided in the endoscopes 2 and 2I is used to control the CCD 9 of the endoscope.
Although the sensitivity is designated, the control means 21 in the signal processing device 4 may be provided with an input means such as a keyboard so as to cope with the case of an endoscope without the ROM 48 (for example, 2D). (Or sensitivity specifying means) is connected, and an input for specifying a sensitivity when an appropriate observation image is obtained for the endoscope 2D is performed from the input means, and CCD sensitivity control is performed via the control means 21. The sensitivity of the CCD 9 provided in the endoscope 2D may be controlled from the means 12.

Instead of inputting the designation of the sensitivity from the input means, the characteristics of the endoscope 2D, specifically, the number of light guides and the lens aperture value shown in FIG. Sensitivity control pulse φCM requiring 21
The sensitivity of the CCD 9 may be controlled via the CCD sensitivity control means 12 by calculating the number of pulses of D.

(Second Embodiment) FIG. 7 shows a second embodiment of the present invention.
1 shows a configuration of an endoscope device 51 according to an embodiment. The description of the parts common to FIG. 1 is omitted.

In the first embodiment, the frame sequential light source device 22 is built in the processor 3 together with the signal processing device 4 such as the signal processing means 14. Is provided with a surface-sequential light source device 52.

In the surface-sequential light source device 52, a half mirror 53 is disposed in front of the lamp 27 inside the device. The light emitted from the lamp 27 is split by the half mirror 53, and the reflected light is converted into a light amount detection unit 54. It is led to.

Since the amount of light emitted from the lamp 27 deteriorates in accordance with the lamp lighting time, the degree of decrease in the amount of light is converted into numerical data by the light amount detection unit 54 and transmitted to the control unit 21 via the control unit 26. Sent. The control means 21 calculates the sensitivity setting value of the CCD 9 so as to correct the decrease in the light amount of the lamp 27 based on the numerical data, and controls the CCD sensitivity control means 12.

Further, information from the aperture control means 24 via the control means 26 also indicates whether the aperture 23 is in a range where the dimming control operation is possible, or whether the aperture 23 is in a fully open state or a fully closed state. To the control means 21.

The control means 21 controls the CCD sensitivity control means 12 so as to increase the sensitivity setting value of the CCD 9 when the aperture 23 is fully open, and the CCD sensitivity when the aperture 23 is fully closed.
CCD sensitivity control means 1 so as to lower the sensitivity setting value of
2 is controlled. These sensitivity setting values may be changed stepwise or may be changed continuously. Other configurations are the same as those of the first embodiment.

In this embodiment, in addition to the operation of the first embodiment, the actual emitted light amount of the lamp 27 is detected in consideration of the case where the lamp 27 changes due to aging or the like. The effect of the change is calculated by the CCD sensitivity control means 12
There is provided a means for solving the problem by controlling the sensitivity of D9.

According to the second embodiment, the light source device 5
Even when the light emitted from the second lamp 27 is reduced or when the dimming control by the diaphragm 23 is not effective, the light source device 52
By controlling the sensitivity of the CCD 9 as a solid-state imaging device on the basis of information from the camera, the endoscope device 51 capable of obtaining an observation image with appropriate brightness can be realized.

(Third Embodiment) FIG. 8 shows a third embodiment of the present invention.
1 shows a configuration of an endoscope device 51 ′ according to an embodiment. The description of the portions common to FIGS. 1 and 7 is omitted. This embodiment is different from the second embodiment shown in FIG.
The LED light source device 52 'of FIG. 8 can be used in place of the field sequential light source device 52 of FIG.

The LED light source device 52 'shown in FIG.
A red LED 57a, a green LED 57b, and a blue LED 57c that are connected to the LED control means 56 and are sequentially turned on and off.
In addition, a condensing lens 28 for condensing the light flux of the illumination light on the rear end face of the light guide 15 is provided, and the light is supplied to the rear end face of the light guide 15 face-sequentially.

A red LED 57a and a green LED 57
b, A stop 23 is disposed between the blue LED 57c and the condenser lens 28, and is controlled by a stop control means 24. The aperture control means 24 and the LED control means 56 are
It is connected to the.

The control means 21 in the signal processing device 4
The red LED 57a, the green LED 57b, and the blue LED L of the LED light source device 52 that supplies the illumination light in a frame sequence to the endoscope 2
The light emission control of the ED 57c is also connected to the control means 26 for controlling the light emission timing of each LED via the LED control circuit 56, so that the CCD drive means 11 and the signal processing means 14 are controlled in synchronization with the light emission timing of each LED. ing.

The control means 21 indicates that the xenon lamp is used when the field sequential light source device 52 is connected, and that the LED is used when the LED light source device 52 'is connected. When a light source device (not shown) using a halogen lamp is connected, information indicating that the halogen lamp is used is transmitted from the control means 26 in each light source device. The control means 21 controls the CCD sensitivity control means 12 based on this information.

As described above, according to the third embodiment, the light source device 5
Even when the absolute value of the emitted light is different due to the difference between the types 2 and 52 ', the sensitivity of the solid-state imaging device is controlled so as to correct the emitted light amount based on the information from the connected light source device. An endoscope apparatus capable of obtaining an observation image of brightness can be realized.

(Fourth Embodiment) FIG. 9 shows a fourth embodiment of the present invention.
1 shows a configuration of an endoscope apparatus 61 according to an embodiment. In the present embodiment, a simultaneous endoscope apparatus is provided in which a color filter 65 is provided on the front surface of the CCD 9.

Description of portions common to FIG. 1 or FIG. 7 is omitted. In this embodiment, a simultaneous endoscope 62 is used.
A light source device 63 for supplying white illumination light to the endoscope 62; a signal processing device 64 for driving and signal-processing the CCD 9 (for example, separate from the light source device 63); and an output from the signal processing device 64 And a monitor 5 for displaying a video signal to be displayed.

The endoscope 62 of the simultaneous type is provided with a color filter 65 on the front surface of the CCD 9 of the endoscope 2 of the first embodiment, for example.

The light source device 63 is different from the field sequential light source device 22 of FIG. 1 in that the RGB rotation filter 29 inserted in the illumination light path is removed, and the white light of the lamp 27 is
The light guide 1 is condensed by the condensing lens 28 through the light guide 1
5 is supplied to the rear end face. Therefore, neither the motor 30 nor the RGB rotation filter control means 25 in FIG. 1 is provided.

Further, the signal processing device 64 in the present embodiment replaces the signal processing means 14 of FIG.
And post signal processing means 67.

That is, a pre-signal processing means 66 for performing various signal processing of the output signal read from the CCD 9, and a post signal processing means for performing various signal processing for outputting the output signal of the pre-signal processing means 66 to the monitor 5 or the like. A signal processing means 67 for converting an output signal read from the CCD 9 into a television signal,
And so on.

The CCD driving means 11 and the CCD
The sensitivity control unit 12 and the signal processing unit 14
And the control is performed by the control means 21.

The control means 21 is also connected to a control means 26 for controlling the stop 23 and the stop control means 24 provided in the light source device 63 for supplying white illumination light to the endoscope 62.

Signal processing means 1 used in this embodiment
4 is configured, for example, as shown in FIG. The signal output from the endoscope 62 is input to the pre-signal processing means 66.

In the pre-signal processing means 66, the output signal of the CCD 9 on which the color component is superimposed is output to the CDS circuit 31, LP
A / D converter 34 via F32 and clamp circuit 33
Is converted into a digital signal. This digital signal is isolated and transmitted from the patient circuit to the secondary circuit by the photocoupler 35a.

The output signal passing through the photocoupler 35a is separated into a luminance signal Y and color difference signals RY and BY by a luminance / color difference signal separation circuit 68 in a secondary circuit, and further, an RGB signal by a matrix circuit 69. After the white balance correction, the color tone adjustment, and the gamma correction performed by the white balance correction circuit 36, the color tone adjustment circuit 37, and the gamma correction circuit 38, the electronic zoom processing is performed by the enlargement circuit 39. The output of the enlargement circuit 39 is input to the post signal processing means 67 via the contour emphasis circuit 40.

The output of the contour emphasizing circuit 40 is supplied to a still image memory 45 for storing a still image in the post signal processing means 67.
a, 45b, and 45c and the selector 46. The output of the contour emphasizing circuit 40 via the selector 46 is supplied to the monitor 5 as a moving image via a 75Ω driver 47 at the subsequent stage.

The outputs of the still picture memories 45a, 45b and 45c are connected to the other input terminal of the selector 46. Image writing and image reading of the still image memories 45a, 45b, and 45c are controlled by the control unit 21, and in response to a freeze command of the operator, the control unit 21 stores the image at the time of the freeze command. Control the still image memories 45a, 45b, 45c.

The control means 21 controls the CCD driving means 11 so that the electronic shutter operation is performed in response to the freeze command, and controls the CCD sensitivity control means 12 to increase the CCD sensitivity setting value. Control. This sensitivity setting value is set so as to correct the decrease in exposure time due to the electronic shutter operation. When the electronic shutter operation of 1/120 second is performed, the sensitivity is twice as high as that in the normal exposure of 1/60 second. Is set to CCD9.

As described above, according to the present embodiment, even during the electronic shutter operation, the sensitivity of the solid-state image sensor is controlled in accordance with the driving state of the solid-state image sensor to obtain an observation image with appropriate brightness. The endoscope device which can be realized.

(Modification of Fourth Embodiment) A modification of the fourth embodiment of the present invention will be described with reference to FIG. 9 of the fourth embodiment. In this modification, the NTSC system (60H
2A and 2B show a simultaneous endoscope apparatus which can be connected to both monitors of the PAL system (50 Hz). Signal processing device 6
Reference numeral 4 indicates that a TV system can be selected by a switch (not shown). If NTSC is selected, C
The imaging process of CD9 is performed at 60 Hz, and the signal processing for converting into the NTSC television signal is performed.
The control means 21 controls the CCD driving means 11, the pre-signal processing means 66, and the post-signal processing means 67.

When the PAL system is selected, the CCD 9
The control means 21 controls the CCD driving means 11, the pre-signal processing means 66, and the post-signal initiating means 67 so as to carry out the signal processing for converting the imaging rate of the PAL at 50 Hz and converting it into a PAL television signal. At this time, the control means 2
Reference numeral 1 also controls the sensitivity setting value of the CCD 9 in accordance with the switching of the imaging rate, and controls the CCD sensitivity control means 12 so that the same video signal level is obtained at the time of 60 Hz imaging and 50 Hz imaging.

As described above, according to the present modification, even when the imaging rate is different or the exposure time is different, by controlling the sensitivity of the solid-state imaging device in accordance with the driving state of the solid-state imaging device, appropriate brightness is obtained. An endoscope device capable of obtaining an observation image of the same can be realized.

(Fifth Embodiment) FIG. 11 shows a configuration of an endoscope apparatus according to a fifth embodiment of the present invention. The description of the parts common to those in FIG. 1 or FIG. 9 is omitted. An endoscope device 61 'according to the present embodiment includes an endoscope 62, a light source device 63', a signal processing device 64 ', and a monitor 5.

The light source device 63 'in this embodiment is the same as the light source device 63 of the endoscope device 61 shown in FIG.
3. The aperture control means 24 and the control means 26 are removed, and the illumination light of the lamp 27 is condensed by the condenser lens 28 and supplied to the rear end face of the light guide 15.

That is, this light source device 63 'is not provided with a stop mechanism, and the same amount of irradiation light is always input to the rear end face of the light guide 15.

The signal processing device 64 'of the present embodiment is different from the signal processing device 64 of FIG. 9 in that a pre-signal processing device 66', which is partially different from the pre-signal processing device 66 in the signal processing device 14, in configuration. Has been adopted. FIG. 12 shows the configuration of the pre-signal processing means 66 '.

The pre-signal processing means 66 'shown in FIG. 12 differs from the pre-signal processing means 66 shown in FIG.
The average value detection filter circuit 70 to which the output signal is input is provided.

The average value detection filter circuit 70
Calculates the average value of the luminance signal Y for one screen output from the CCD 9, and sends the average luminance value to the control means 21. The control means 21 calculates the sensitivity setting value of the CCD 9 based on the average luminance value so as to obtain an observation image of appropriate brightness, and controls the CCD sensitivity control means 12.

As described above, according to the present embodiment, the endoscope apparatus 6 which obtains an observation image with appropriate brightness by controlling the sensitivity of the solid-state imaging device according to the output signal of the solid-state imaging device.
1 'can be realized, and the configuration of the light source device 63' can be simplified.

(Sixth Embodiment) FIG. 13 shows a configuration of an endoscope apparatus according to a sixth embodiment of the present invention. The description of the parts common to FIG. 1 is omitted.

The endoscope device 71 comprises the endoscope 2, a video processor 73 having the frame sequential light source device 22 and the signal processing device 74, and the monitor 5.

In this embodiment, the ROM 48 in the endoscope 2
Stores information (data) of variation in electron multiplication factor for each pixel of the CCD 9.

In the signal processing device 74 of this embodiment, the signal processing device 4 of FIG. 1 further includes a storage means 75 for storing data of the ROM 48, a switch 76 for freely setting the sensitivity of the CCD 9, and a variation. And calculating means 78 for calculating correction data to be corrected by calculation.
The signal processing means 14 employs a pre-signal processing means 17 'having a partially different configuration instead of the pre-signal means 17 shown in FIG. The sensitivity set by the switch 76 can be set even when the sensitivity varies.

Then, as in the first embodiment, when the endoscope 2 is connected to the processor 73, the information in the ROM 48 is sent to the storage means 75 in the processor 73 and stored. For example, information of a sensitivity setting value provided on a panel of the processor 73 and set by a switch 56 for freely setting the sensitivity of the CCD 9 is input to the control means 21, and the control means 21 responds to the information by the CCD sensitivity. The control unit 12 is controlled.

In this embodiment, the sensitivity is controlled by the number of φCMD pulses, and the calculating means 78 calculates the variation in the electron multiplication factor for each pixel stored in the storage means 75 and the number of φCMD pulses. The correction data is calculated based on.

When the electron multiplication factor of a certain pixel is kX and the electron multiplication factor of a pixel is n and the pulse number of φCMD is n, the correction data of the pixel is 1 / X.
(KX) ＾ n.

The correction data for each pixel is multiplied by the output signal read from the CCD 9 by the multiplier 79 constituting the pre-signal processing means 17 'shown in FIG. It is sent to the stage side circuit. The pre-signal processing means 17 'shown in FIG. 14 is different from the pre-signal processing means 17 in FIG. 2 in that a multiplier 79 is provided between the photocoupler 35a and the white balance correction circuit 36.

FIG. 15 shows the CCD 9 used in the present embodiment. Below the light receiving surface 80, there are a serial register 81 and an FDA 82 for converting charges into a voltage. Six dummy pixels 83 exist between the serial register 80 and the FDA 82.

The control means 21 performs different control based on the set value from the switch 76 between the normal sensitivity where the sensitivity is not increased and the electron multiplication.

That is, the control means 21 does not perform the electron multiplying operation based on the set value from the switch 76, that is, at the time of the normal sensitivity in which the sensitivity is not increased, as shown in FIG.
As shown in (A), the CCD output signal (C
A timing signal is sent to the clamp circuit 33 so as to perform clamping in the OB period in which the DS output signal is input.

On the other hand, at the time of electron multiplication in which the electron multiplication operation is performed to increase the sensitivity, as shown in FIG.
Since the dark current of the pixel 84 is multiplied and affects the potential to be OB-clamped, the dummy pixel 8 is controlled to avoid this.
A timing signal at a different clamp position is sent to the clamp circuit 33 so as to perform clamping in a dummy period in which the CCD output signal of No. 3 is input.

As described above, according to the present embodiment, the output signal of the solid-state image sensor is changed according to the data of the variation in the electron multiplication factor for each pixel of the solid-state image sensor and the set value of the sensitivity of the solid-state image sensor. By performing the correction, an endoscope that can obtain a good observation image can be realized.

Further, by controlling the signal processing of the output signal of the solid-state imaging device according to the sensitivity set value of the solid-state imaging device, a correct black level can be reproduced and a good observation image can be obtained.

Note that, in the above description, the CCD 9 is
Although the case of an electronic endoscope in which (is built in) is described, the present invention is not limited to this, and a television camera in which a television camera having a built-in CCD is attached to an eyepiece of an optical endoscope. It can also be applied to the case of a wearing endoscope.

In this case, for example, as described in the first embodiment, an input for designating the sensitivity of the CCD 9 from the input means (designating means) to the control means 21 may be performed. Further, the characteristics of the television camera are input together with the characteristics of the optical endoscope (the number of light guides, etc.), and the control means 21 controls the sensitivity control pulse φCM required in that case.
The sensitivity of the CCD 9 may be controlled via the CCD sensitivity control means 12 by calculating the number of pulses of D.

(Seventh Embodiment) FIGS. 17 to 23
FIG. 17 relates to a seventh embodiment of the present invention, FIG. 17 is a block diagram showing a schematic configuration of an endoscope apparatus, FIG. 18 is an explanatory diagram showing a configuration of two filter sets provided in a rotary filter,
FIG. 19 is a block diagram showing a pre-signal processing means constituting the signal processing means, FIG. 20 is a block diagram showing a field sequential synchronizing means and a post signal processing means constituting the signal processing means, and FIG. 21 is a timing of driving the CCD. Chart, FIG. 22
Is a graph showing the relationship between the illuminance of the CCD plate surface and the S / N, FIG.
3 is a graph showing the relationship between the illuminance of the CCD surface and the output voltage.

As shown in FIG. 17, an endoscope apparatus 101 according to the seventh embodiment includes an electronic endoscope (hereinafter abbreviated as an endoscope) 102 having a built-in solid-state image pickup device, and Mirror 10
2 is detachably connected to a processor 103 having a signal processing device 104 and a frame sequential light source device 122 therein, and a monitor 105 connected to the processor 103 and displaying a video signal processed by the processor 103. It is composed of

The endoscope 102 has an elongated insertion portion 106 to be inserted into a body cavity, and a distal end portion 107 of the insertion portion 106 has an objective lens 108 for forming an image of a subject, and an objective lens 108 An image sensor as a solid-state imaging device, for example, a charge-coupled device (abbreviated as CCD)
The CCD 109 is connected via signal lines to CCD driving means 111 and CCD impression control means 112 provided in the signal processing device 104 in the processor 103. The CCD driving means 111 and CCD impression control means 112 Exposure, doubling of the generated charge, and readout control are performed by the drive signal and the sensitivity control signal generated in step (1).
Further, the image sensor may be a CMOS sensor. CC
On the front surface of D109, a filter 110 that transmits only a specific wavelength region is arranged. Filter 110
Has a spectral transmittance characteristic of transmitting a wavelength band of auto-fluorescence emitted from a living tissue and cutting (not transmitting) excitation light.

The CCD 109 is a U.S.A. S. Pat. N
o. 5,337,340 "Charge Multip
Lying Detector (CMD) suite
left small pixel CCD ima
Ge sensors ".
The feature is that an electron multiplication mechanism (hereinafter referred to as CMD: Charge Mull) is provided for each pixel or before the detection amplifier (after the horizontal transfer register).
A tiplying detector is provided, and an electron multiplier (CM)
When an electric field (energy about 1.5 times the energy gap) is applied to D), the signal charges (electrons) collide with the electrons in the valence band and are excited into the conduction band, and are impacted by impact ionization (secondary ionization). A hole pair is generated. In other words, when pulses having a certain intensity (amplitude) are sequentially applied, electron-hole pairs are generated one after another due to the impact ionization phenomenon, so that the signal charge is arbitrarily multiplied by controlling the number of pulses. Have.

The CCD 109 includes a buffer 113 and a CCD.
A subject image formed on the imaging surface of the CCD 109 via the objective lens 108 and the filter 110 is connected to a signal processing unit 114 provided in the processor 103 via a cable 120 (signal line). The output signal is supplied to the signal processing unit 114.

FIG. 21 shows the exposure time / light-shielding time (CCD readout period) of the rotary filter 129 described later, and the impression control pulse φCMD for the CCD 109 in that case.
Vertical transfer pulse φIAG, horizontal transfer pulse φSR and C
3 shows the relationship between CD output signals. The CMD of the CCD 109 is
The CMD can be set for each pixel or in the stage preceding the detection amplifier. Here, the CMD is set for each pixel. The sensitivity (CMD multiplication factor) of the CCD 109 is φ
Although it is possible to control either the number of pulses of the CMD or the pulse amplitude (voltage value), here, the desired number of pulses (CMD multiplication factor) is obtained by controlling the number of pulses.
In this case, a sensitivity control pulse φCMD is output to the CCD 109 during a light-shielding period (reading period) after the exposure period, and
The sensitivity (CMD multiplication factor) is increased and the generated charge is multiplied. Thereafter, a vertical transfer pulse φIAG and a horizontal transfer pulse φSR are output to the CCD 109 and the CCD 10
9 to obtain an output signal. That is, the sensitivity control pulse φC
The desired sensitivity (CMD multiplication factor) of the CCD 109 is obtained by changing the number of MD pulses.

The endoscope 102 is provided with a light guide 115 for transmitting illumination light, which can transmit ultraviolet to near-infrared light. An illumination lens 116 is provided on the distal end side of the light guide 115. Illumination light for observation of normal light or special light obtained by guiding the endoscope 102 by 115 is applied to the subject via the illumination lens 116. As the light guide 115, an SLF fiber (trade name), a quartz fiber, or the like can be used.

The signal processing means 114 performs pre-signal processing means 117 for performing various kinds of signal processing of the output signal read by the CCD 109, and a frame sequential simultaneous signal for synchronizing the frame sequential signals output from the pre signal processing means 117. Means 118,
The output signal of the frame sequential synchronization means 118 is monitored by the monitor 105.
And post signal processing means 119 for performing various signal processing for output to the CCD 109 and the like.
Is converted into a television signal and output to the monitor 105 or the like.

The CCD driving means 111, the CCD sensitivity control means 112, and the signal processing means 114 are connected to the (first) control means 121, and the control is performed by the control means 121. The control unit 121 controls a stop 123, a stop control unit 124, and an RGB rotation filter control unit 125 provided in a plane sequential light source device 122 that guides the plane sequential illumination light to the endoscope 102 (second). ) Control means 1
26, the RGB rotation filter control means 1
The CCD driving means 111 and the signal processing means 114 are controlled in synchronism with the control signal 25.

The surface-sequential light source device 122 includes a lamp 127 for generating illumination light of a wide band from the ultraviolet region to the infrared region, a condensing lens 128 for condensing the light flux of the illumination light on the rear end face of the light guide 115. , An RGB rotation filter 129 inserted between the lamp 127 and the condenser lens 128. The lamp 127 includes a xenon lamp, a halogen lamp, a metal halide lamp, an LED,
High-pressure mercury or the like can be used.

This rotary filter 129 is
Is rotatably connected to the rotation shaft of the light guide 115, and is controlled by the control means 126 to rotate at a predetermined speed via the RGB rotation filter control means 125, and the surface sequential light is guided to the rear end face of the light guide 115. . Rotary filter 129
Has a double structure as shown in FIG. 18, and has two filter sets 133, 13 at the inner peripheral portion and the outer peripheral portion.
4 are provided. The inner first filter set 133 is composed of three filters R1, G1, and B1 for normal light mode (normal light observation), and the second filter set 134 on the outer periphery is special light mode (special light mode). R for observation)
The first filter set 133 and the second filter set 134 have spectral transmittance characteristics corresponding to observation purposes, respectively. That is, the first filter set 133 includes the filters 133a, 133b, and 13 that transmit the red (R1), green (G1), and blue (B1) wavelength regions for the normal light mode (normal light observation).
3c are arranged in a fan shape, discretely along the circumferential direction, and further on the outer peripheral side thereof are R for special light mode (special light observation).
2, a filter 1 that transmits light in each wavelength region of G2 and B2
34a, 134b and 134c are discretely arranged.

A light-shielding portion is provided between the filters 133a, 133b, and 133c that transmit the red (R1), green (G1), and blue (B1) wavelength regions for the normal light mode (normal light observation). I have. The light-shielding portion corresponds to a light-shielding period (readout period) of the CCD 109, and corresponds to the filter 133.
The light-shielding portions a, 133b, and 133c are arranged at substantially the same intervals. The second filter set 134 is similarly configured.

In the present embodiment, the filter 134b
Is equipped with an excitation filter that transmits only light in the ultraviolet to blue region used in the special light mode, and can generate autofluorescence from living tissue. In this embodiment, the filters 134a (R2) and 134c (B2) are shielded from light and are not irradiated.

On the illumination optical axis connecting the lamp 127 and the rear end face of the light guide 115, the filter set 1 on the inner peripheral side is provided.
A rotary filter switching mechanism 131 is provided so that the filter set 33 and the outer filter set 134 can be selectively set. In the case of the normal light mode, the light beam P1 (shown by a solid line in FIG. 18) from the lamp 127 is opposed to the filter set 133 on the inner peripheral side. On the other hand, in the special light mode, the light beam P2 from the lamp 127 (shown by a dotted line in FIG.
The filter set disposed on the illumination optical path can be switched by moving the entire rotary filter 129 by the rotary filter mechanism 131 so as to oppose the filter set. The rotation filter switching mechanism 131 moves the motor 130 and the rotation filter 129 relatively to the lamp 127,
The lamp 127 may be moved in the opposite direction.

Further, the processor 103 is connected to the mode switching means 135, and the observation mode (normal light / special light)
Is performed, a rotation filter switching instruction signal is output to the rotation filter switching mechanism 131 and the control means 126, and the rotation filter 129 is switched, and at the same time, in the special light mode, via the aperture control means 124. The aperture 123 is controlled to be fully opened automatically.

The rotation filter switching instruction signal is transmitted to the control unit 1
21 to the selected mode (normal light /
The control means 121 to the signal processing means 114, the CCD driving means 111 and the CCD
The sensitivity control unit 112 is controlled.

The signal processing means 114 is configured, for example, as shown in FIG. In FIG. 19, an output signal from the CCD 109 is input to the pre-signal processing means 117. In the pre-signal processing means 117, the output signal of the CCD 109 is output to the preamplifier 140
S circuit 141, LPF 143, clamp circuit 144, A
The signal is converted into a digital signal by an A / D converter 146 via a GC circuit (auto gain control) 145. This digital signal is isolated and transmitted from the patient circuit to the secondary circuit by the photocoupler 147a. The secondary circuit includes a white balance correction circuit 14.
8. A color tone adjustment circuit 149 and a gamma correction circuit 150 are provided. After white balance correction, color tone adjustment, and gamma correction are respectively performed, the enlargement circuit 151 performs enlargement by electronic zoom processing.

The output signal of the enlarging circuit 151 is inputted to the frame sequential synchronizing means 118 via the contour emphasizing circuit 152. Further, after the CDS circuit 141, a photometric unit 142 is connected, calculates an average value of one output screen of the CCD 109, and outputs the average value to the control unit 121. Further, the control unit 121 outputs a control signal for controlling the operations of the white balance correction circuit 148, the color tone adjustment circuit 149, the enlargement circuit 151, and the outline emphasis circuit 152 in the secondary circuit, and a photo coupler as an isolation transmission unit. A control signal for controlling the operation of the clamp circuit 144 in the patient circuit is output via 147b.

R output from pre-signal processing means 117
The GB plane-sequential signal is input to the synchronizing means 163a, 163b, 163c via the changeover switches 160, 162A, 162B in the plane-sequential signal synchronizing means 118 shown in FIG. Synchronization means 163a, 163
b, 163c have at least one screen of memory,
The frame-sequential signals input sequentially in the order of R, G, and B are stored in memories for each color, and the stored frame-sequential signals are simultaneously read out and output as synchronized signals.

Synchronization means 163a, 163b, 163c
As an example, each synchronization unit 163 shown in FIG.
I (I = a, b, c) can be constituted by means having image memories 164a and 164b for at least two screens. The synchronizing means 163a corresponds to the video signal obtained by 133a or 134a of the rotation filter 129. Similarly, the synchronizing means 163 b
The reference numeral 133 b or 133 a of the rotary filter 129 corresponds to the 133 c or 134 c of the rotary filter 129. Here, image writing and image reading of the image memories 164a and 164b are alternately switched to perform synchronization. The synchronization means 163a, 163b, 1
The synchronized output signal 63c is input to the still image memories 165a, 165b, and 165c for storing the still image in the post signal processing means 119 and also to the selector 166. The synchronizing output of the synchronizing means 163a, 163b, 163c via the selector 166 is output to the monitor 1 via a 75Ω driver 167 at the subsequent stage as a moving image.
05. Still image memories 165a, 165b, and 165c are connected to the other input terminal of the selector 166.

Still picture memories 165a, 165b, 16
Image writing and image reading of 5c are performed by the control unit 121.
In response to an external freeze command, the control means 121 controls the still image memories 165a, 165b, and 16 so as to store the image at the time of the freeze command.
5c, and for the selector 166,
Moving picture symbols and still picture memories 165a, 165b, 165c which are output from the synchronizing means 163a, 163b, 163c
Out of the still image signal, which is an output signal, is supplied to the monitor 105 via the 75Ω driver 167 at the subsequent stage.

[0129] The endoscope 102 has a built-in ROM 170 storing information unique to the endoscope. When the endoscope 102 is connected to the processor 103, the information is processed by the signal processing inside the processor 103. It is transmitted to the control means 121 in the device 104 and controls the sensitivity of the CCD 109 (CM
D multiplication factor control) and the like. That is, R
The OM 170 forms a designating unit for designating the sensitivity of the CCD 109.

(Operation) The operation in the normal light mode and the special light mode will be described.

First, when the normal light mode (normal light observation) is performed, the rotation filter 129 is set to the first filter set 1.
Reference numeral 33 is arranged on the illumination light path, and the CMD multiplication factor of the CCD 109 is set to a fixed value. The set value (fixed value) for the normal light mode of the CMD multiplication factor of the CCD 109 is the endoscope 102.
Is transmitted from the ROM 70 when connected to the processor 103.

The CCD sensitivity control means 112 includes the control means 1
21 receives the CMD multiplication factor (fixed value) of the CCD 109 transmitted from the ROM 70 via the
Calculate the number of pulses corresponding to MD multiplication factor (fixed value),
In synchronization with the exposure / shielding (readout period) of CD109, C
The calculated number of pulses are output to CD109.

It is to be noted that, for example, input means (or designation means) such as a keyboard is provided to the control means 121 in the signal processing device 104.
And the user can manually input an arbitrary CMD multiplication factor from the input means, and can set the CMD multiplication factor of the CCD 109 from the CCD sensitivity control means 112 via the control means 121. This is the same in the special light mode.

The illumination light emitted from the lamp 127
By passing through the filter set 133, R (red), G
(Green) and B (blue) surface-sequential illumination light is sequentially radiated onto the living tissue, and the reflected light is smoothly imaged by the CCD 109.
The G and B image signals (video signals) are input to the signal processing unit 114, and a normal light observation image is displayed on the monitor 105.

The photometric means 142 is a CCD 10 for one screen.
The average value of the output signal from the control unit 9 is calculated and output to the control unit 121. The output value is output to the second control means 126 via the control means 121, and a command is issued to the aperture control according to the value to control the opening and closing of the aperture 123. In other words, if the subject is too bright than the set reference value,
Since the output signal 109 becomes large, the direction in which the diaphragm 123 is closed (the irradiation intensity on the rear end face of the light guide becomes small)
On the other hand, when the subject is dark, the output signal of the CCD 109 becomes small. Therefore, the CCD 123 is operated in the opening direction (the irradiation intensity on the rear end face of the light guide is increased) to change the irradiation intensity on the living tissue. (Automatic light control function).

The brightness of the monitor 105 (the reference value)
Is connected to input means (or designation means) such as a keyboard to the control means 121 in the signal processing device 104, for example.
The user can set any brightness from the input means.

The AGC circuit 145 can electrically amplify the output signal of the CCD 109 so that the brightness of the monitor 105 is set. That is, even if the subject is dark and the automatic light control function is activated, the monitor 105
When the brightness cannot be obtained, the output signal from the CCD 109 can be electrically amplified (AGC function).

The intensity of the reflected light obtained when the living tissue (digestive organ, bronchus, etc.) is irradiated with light in a plane sequence (red, green, blue) is generally larger than l [lux] in FIGS. 22 and 23, it can be seen from FIGS. 22 and 23 that as the CMD multiplication factor of the CCD 109 increases, the S / N and the output value are improved as compared with the case where the CMD multiplication of the CCD 109 is not performed.

In the normal light mode (normal light observation), even when the brightness of the subject (living tissue) (reflected light intensity from the subject) changes, the monitor 105 is controlled by the automatic light control function and the AGC function. On the top, an observation image with appropriate brightness set by the user is always obtained. Moreover, in this case, C
By increasing the CMD multiplication factor of MD109, S /
N also improves. Thus, normal light mode (normal light observation)
Is performed, an observation image with appropriate brightness can be obtained without deteriorating the image quality by the automatic dimming function. When the image cannot be covered by this function, adjustment is performed by the AGC function.

On the other hand, when the special light mode (special light observation) is performed, the user operates the rotary filter switching mechanism 131 by operating, for example, a mode switch which constitutes the mode switching means 135 to operate the rotary filter 12.
Along with the ninth second filter set 134 being arranged on the illumination light path, the diaphragm 129 operates so as to be fully opened, and the strongest excitation light is incident on the rear end face of the light guide 115.
The sensitivity of the CCD 109 is CMD compatible with the special light mode.
Observation is performed with the multiplication factor set to a fixed value. The set value (fixed value) of the CMD multiplication factor of the CCD 109 is a value transmitted from the ROM 170, and is set in advance to a value larger than that in the normal light mode (normal light observation).

The CCD sensitivity control means 112 includes the control means 1
CCD 109 output from ROM 170 via
CMD multiplication factor (fixed value), and calculates the number of pulses corresponding to the CMD multiplication factor (fixed value) in the special light mode,
The calculated number of pulses are output to the CCD 109 in synchronization with the exposure / light shielding (readout period) of the CCD 109.

The excitation light (ultraviolet to blue region in this embodiment) emitted from the lamp 127 is supplied to the second filter set 134.
In this embodiment, the filter 134b (G
Only the excitation light of 2) is intermittently applied to the living tissue. In this embodiment, the filters 134a (R2) and 134c (B2) are not irradiated because they are shielded from light.

The objective lens 108 receives the reflected light of the excitation light from the living tissue and the autofluorescence (for example, due to NADH and flavin) emitted from the living tissue by the excitation light. Is cut and CC
Auto-fluorescence enters D109. The autofluorescence image captured by the CCD 109 is input to the signal processing unit 114. The signal processing means 114 includes a filter 134b (G2)
Are processed and displayed on the monitor 105.

The AGC circuit 145 electrically amplifies the output signal of the CCD 109 to a set value. That is, when the subject is dark and the output signal of the CCD 109 is smaller than the set value even when the CMD multiplication is performed by the CCD 109, the amplifier is electrically amplified to amplify the intensity of the output signal (AGC function). Thus, a special light observation image having appropriate brightness can always be obtained on the monitor 105.
The brightness of the monitor 105 (the reference value) can be determined, for example, by connecting input means (or designation means) such as a keyboard to the control means 121 in the signal processing device 104, and allowing the user to set the desired brightness from the input means. Can be set.

Here, when the CMD multiplication factor of the CCD 109 is increased (assuming that the CMD multiplication factor is 3 or 10), the S / N and the S / N of the observed image (autofluorescence image in this embodiment) displayed on the monitor 105 are increased. The brightness will be described (FIG. 2
2, see FIG. 23).

S / N reflects the extent to which a dark subject can be imaged, and the image quality of a dark subject, and is very important especially when faint light such as autofluorescence is imaged. This is an important parameter. The output value is a very important parameter like S / N to reflect the brightness of the image displayed on the monitor. When the solid-state imaging device is a general CCD (without a multiplication mechanism), the S / N and brightness of the observation image displayed on the monitor 105 are CMD multiplication of the CCD 109 by 1 (no multiplication).
Roughly corresponds to

When a living tissue (digestive organ, bronchus, etc.) is irradiated with ultraviolet to blue light, autofluorescence due to NADH, flavin, collagen and the like contained in the living tissue is obtained. However, the auto-fluorescence intensity is very weak (FIG. 22, FIG. 2).
3 generally corresponds to an area smaller than 1 [lux]), and it is very difficult to image with a general CCD. 22nd
FIGS. 23 and 23 show that as the CMD multiplication factor of the CCD 109 increases, the S / N and the output value are greatly improved as compared with a general CCD.

Regarding the sensitivity characteristics of CCD 109, CCD 1
09 Plate surface illuminance (reflection of subject brightness) on plate surface (imaging surface) and S / N obtained at output stage of processor 103
The relationship between (signal-to-noise ratio) and the output value will be described.

The target system is an endoscope 101 (CCD 10
9 + CCD cable 120 + processor 103 (signal processing means 114)), and theoretically calculates a signal-to-noise ratio S / N and an output value S at an output stage of the processor 103 (signal processing means 114).

S / N = S / {NCCD ² + NCV ² } ^1/2 (1) = {A · n · K · (1-β) · G} / ｛(A ² · F ² · (n + D) + R ^{2) · K 2 · (1} -β) 2 · G 2 + NCV 2} 1/2 (1-2) = {n · K · (1-β) · G} / {(F 2 · (n + D) + R ² / A ² ｝ · K ² · (1-β) ² · G ² + NCV ² / A ² ｝ ^1/2 (1-3) S = A · n · K · (1-β) · G [mV] (2) S: signal output value (＠output stage of processor 103) (Pedestal is assumed to be 0 for simplicity of calculation) NCCD: amount of noise generated in CCD 109 (＠output stage of processor 103) NCV: CCD cable 120 + processor 103 Amount of noise generated at (output stage of processor 103) [Parameters] 1) CCD related ・ n [e / pixel]: For each pixel Number of signal charges that formed (CMD up times before) (n = M × (4.1 × 10 9) × μ 2 × η × RA × T
[E / pixel / frame]) (M [lux]: plate surface illuminance, μ: pixel size, η: quantum efficiency, RA: aperture ratio, T: exposure time) A [times]: CMD multiplication factor D [ e / pixel / s]: Dark current generated for each pixel. R [eRMS]: Readout noise (detection amplifier noise). K [mV / e]: Detection ampoule charge-voltage conversion coefficient. A [times]: CMD (Charge). M
multiplying Detector) multiplication factor ・ F ² : CMD Access
Noise Factor 2) Other than CCD • β [× 100%]: Signal attenuation rate of CCD cable 120 • G [times]: Processor gain (G = processor output value / processor input value) • Ncv [mV]: CCD cable 120 + processor 103 (In a state where a gain is applied) Here, a numerical value is substituted for each parameter of Expression (1-2) and Expression (2), and the plate when the CMD multiplication factor is assumed to be 1, 3, and 10 times FIG. 22 shows the relationship between surface illuminance and S / N, and FIG. 23 shows the relationship between plate surface illuminance and output value. The S / N (vertical axis) in FIG. 22 is S / N = 2.
It is calculated as 0 × log {Equation (1-2)} (in decibels).

(Effect) When the special light mode (special light observation) is performed, a weak subject image is multiplied by the CMD multiplication of the CCD and A
With the GC function, a weak subject image that cannot be captured by a general CCD can be captured. In this case, S / N
In addition, the output value can be improved, and an observation image with good image quality (high S / N) and appropriate brightness can be obtained.

The information output from the ROM 170 includes the value of the CMD multiplication factor of the CD 109 in the normal light / special light mode, the type of endoscope, and the like.
Information on the brightness of the monitor 105 (output value of the processor 103), correction data of the CMD multiplication factor of the CCD 109 for each pixel, and the like may be transmitted to the processor 103.

Further, the endoscope is of a two-CCD type having two CCDs disposed at the distal end, and the first CCD is dedicated to the normal light mode (normal light observation) and the second CCD is the special light mode (special light observation). It may be dedicated. In this case, the second CCD employs the CCD 109 shown in this embodiment, but the first normal light mode dedicated CCD is the CCD 109 or a general CCD.
May be adopted.

Although the rotary filter 129 has three filters corresponding to the special light mode, the number of filters is not limited to three but may be two or less, or four or more.

Although the filter corresponding to the special light mode of the rotary filter 129 has the characteristic of transmitting the ultraviolet to blue region, autofluorescence imaging is performed as a filter that transmits only the characteristic wavelength of the ultraviolet region or only the blue region. May be.

The spectral transmittance characteristics of the filter corresponding to the special light mode of the rotary filter 129 were in the ultraviolet to blue range, but the specific wavelengths in the visible range were drugs (HpD, porphyrin, NPe6, ALA, m-THPC, ATX). -S1
0, BPD-MA, ZnPC, SnET2, etc.) and may be used as a drug fluorescence imaging of PDD (photodynamic diagnosis).

Although the spectral transmittance characteristic of the filter corresponding to the special light mode of the rotary filter 129 is in the ultraviolet to blue region, a drug using a drug (for example, an indocyanine green derivative-labeled antibody) as a specific wavelength in the near infrared region is used. Fluorescence imaging may be used.

Although the spectral transmittance characteristic of the filter corresponding to the special light mode of the rotary filter 129 is in the ultraviolet to blue region, the reflected light may be imaged as a specific wavelength in the visible region. In this case, the filter 110 may not be provided.

The mode switching means 135 is
3, but may be provided on the endoscope 102.

In the processor 103, the signal processing device 104 and the field sequential light source device 122 are integrated, but the signal processing device 104 and the field sequential light source device 122 may be formed separately.

(Eighth Embodiment) In this embodiment,
In the case of normal light observation, automatic light control + AGC is performed, and in the case of special light observation, CMD (fixed value (manual)) + AGC (processor Gain UP) + long-time exposure and full light emission are performed. .

In the seventh embodiment, the normal light mode (normal light observation) and the special light mode (special light observation) have the same exposure time.

In this embodiment, the exposure time is made longer in the special light mode than in the normal light mode, and a higher S / N and a higher output value are realized.

(Structure) FIG. 24 shows the structure of a rotary filter, FIG. 25 is a timing chart in a special light mode of CCD driving, and FIG. 26 is a relation between plate surface illuminance of CCD and S / N (long exposure). FIG. 27 is a graph showing the relationship between the illuminance of the CCD plate surface and the output voltage (long-time exposure).

The description of the parts common to the seventh embodiment, including the rotary filter 129A, is omitted.

As shown in FIG. 24, the rotary filter 129A has a double structure, and two filter sets 133 and 134A are provided on the inner peripheral portion and the outer peripheral portion. The first filter set 133 on the inner peripheral side includes 133a for a normal light mode (normal light observation) as in the seventh embodiment,
It is composed of three filters 133b and 133c. The second filter set 134A in the outer peripheral portion is composed of two filters 134aA and 134c for a special light mode (special light observation), and each has a spectral transmittance characteristic according to the observation purpose.

In the present embodiment, the filter 134aA is provided with a filter for excitation of autofluorescence (ultraviolet to blue region), and the filter 134c is not provided this time (light is shielded). The second filter set 134A of the rotary filter 129A is divided (for convenience) into three regions R2, G2, and B2 as shown in FIG.
The filter 134aA is composed of substantially the entire region of R2 and approximately half of the region of G2.
It consists of almost half of the area, has a fan-like shape, and is arranged along the circumferential direction. Also, the filter 134a
Other than A and 133c, it is a light shielding part.
There are nine light-blocking periods (reading periods).

The control means 121 includes a mode switching means 135
The CCD driving means 11 performs different CCD driving in the selected mode (normal light / special light) based on the
1 is controlled.

FIG. 25 is a timing chart in the special light mode driven by the CCD.
Exposure period / light-shielding period (readout period) for the second filter set (outer peripheral side) of A, and CC in that case
The relationship between the sensitivity control pulse φCMD, the vertical transfer pulse φIAG, the horizontal transfer pulse φSR, and the CCD output signal for D109 is shown. Also, the operation R2, G of the rotation filter
Reference numerals 2 and B3 correspond to the three regions R2, G2 and B2 of the above-described rotary filter 129A, respectively. The sensitivity control pulse φCMD, the vertical transfer pulse φIAG, and the horizontal transfer pulse φSR are output from the CCD sensitivity control unit 112 and the CCD drive unit 111 during the light-shielding period (readout period) after the exposure time only when Gate is ON. Obtain the output signal.

That is, in the eighth embodiment, the Gate is set to O only when the operation of the rotary filter 129A is G2 and B2.
N, each control pulse is output, and an output signal of the CCD 109 is obtained. On the other hand, the operation of the rotation filter 129A is R
In the case of 2, since the Gate is OFF, the output signal of the CCD 109 cannot be obtained. Accordingly, the exposure time is a period obtained by adding the R2 period and the G2 exposure period, and the exposure is approximately three times as long as that of the seventh embodiment. The signal read by the CCD 109 in the G2 light shield is output to the image memory of the synchronizing means 163a and 163b, and the same signal is output to the image memory of the B2 light shield by the image of the synchronizing means 163c. Output to memory. In the normal light mode, Gate is always ON, and the first filter sets 133a, 133b,
After the exposure at 33c, the CCD 109 is read.

(Operation) The operation in the special light mode will be described. The operation in the normal light mode is the same as in the seventh embodiment.

The excitation light (ultraviolet to blue light region in this embodiment) emitted from the lamp 127 is supplied to the second filter set 13.
4A, the filter 134a in this embodiment.
Only the excitation light passing through A is intermittently applied to the living tissue. The filter 134c is not irradiated in this embodiment. The irradiation time of the filter 134aA is about 3 compared to the seventh embodiment.
It is twice. The CCD 109 reads out the signal charges received and accumulated by the CCD 109 during the period in which the living tissue is irradiated with the excitation light from the second filter set filter 134aA during the G2 light-shielding period (reading period). The output signal is input to the signal processing unit 114. The signal processing unit 114 processes the signal read in G2, and displays a special light observation image on the monitor 105.

Here, the long-time exposure of the CCD 109 and C
The S / N and brightness of an observation image (autofluorescence image in this embodiment) displayed on the monitor 105 when the MD multiplication factor is increased will be described.

In the eighth embodiment, the exposure time T ′ is set to about three times the exposure time T of the first embodiment. Also,
The CMD multiplication factor of the CCD 109 is set to 3, 10 times. The relationship between the plate surface illuminance, the S / N, and the output value obtained in this case is shown by performing long-time exposure (irradiation) with the CMD multiplication factor of the CCD 109 shown in FIGS.
It can be seen that the output value is improved. Then, the CMD multiplication factor is increased, and the S / N is further increased by long-time exposure.
It can be seen that the output value is improved.

(Effect) When the special light mode (special light observation) is performed, a weak subject that cannot be imaged by a general CCD can be obtained by multiplying the CMD of the CCD, extending the exposure time, and using the AGC function. An image can be captured. Also, S
/ N and output value are improved, and good image quality (high S /
N) and an observation image with appropriate brightness can be obtained.

The information output from the ROM 170 is stored in the CD 10 in each of the normal light / special light modes.
9 in addition to the value of the CMD multiplication factor, the type of the endoscope, the monitor 1
05 brightness information (output value of processor 103) and CC
The correction data of the CMD multiplication factor of D109 for each pixel may be transmitted to the processor 103.

2C in which two CCDs are arranged at the end of the endoscope
The first CCD is used for the normal light mode (normal light observation), and the second CCD is used for the special light mode (special light observation).
It may be dedicated. In this case, the second CCD employs the CCD 109 shown in the present embodiment, but the first normal light mode dedicated CCD may employ the CCD 109 or a general CCD.

In this embodiment, CCD reading is performed twice during one rotation of the rotary filter.
2, G2 and B2 may be performed only once. In that case, the exposure time can be extended up to about five times that of the first embodiment.

Although the rotary filter 129A has two filters corresponding to the special light mode, the number of filters is not limited to two but may be one.

The filter corresponding to the special light mode of the rotary filter 129A has been described as having a characteristic of transmitting light in the ultraviolet to blue region. May be performed.

The spectral transmittance characteristics of the filter corresponding to the special light mode of the rotary filter 129A are in the ultraviolet to blue region, but the specific wavelength in the visible region is a medicine (HpD, porphyrin, NPe6, ALA, m-THPC, ATX-). S1
0, BPD-MA, ZnPC, SnET2, etc.) and may be used as a drug fluorescence imaging of PDD (photodynamic diagnosis).

The spectral transmittance characteristic of the filter corresponding to the special light mode of the rotary filter 129A is in the ultraviolet to blue region, but the agent using a drug (for example, an indocyanine green derivative-labeled antibody) as a specific wavelength in the near infrared region. Fluorescence imaging may be used.

Although the spectral transmittance characteristic of the filter corresponding to the special light mode of the rotary filter 129A is in the ultraviolet to blue region, the reflected light may be imaged with a specific wavelength in the visible region. In this case, the filter 110 may not be provided.

The mode switching means 135 is
3, but may be provided on the endoscope 102.

In the processor 103, the signal processing device 104 and the field sequential light source device 122 are integrated, but the signal processing device 104 and the field sequential light source device 122 may be formed separately.

(Ninth Embodiment) This embodiment is different from the ninth embodiment in that
The normal light observation and the special light observation are obtained by automatically changing the CMD multiplication factor.

In Example 7, the CMD multiplication factor of the CCD was a fixed value, and the adjustment of the CMD multiplication factor was manually performed. Further, in order to make the brightness of the monitor appropriate, the output signal of the CCD is electrically amplified and adjusted by the AGC function.

(Configuration) FIG. 28 is a block diagram showing a schematic configuration of the endoscope apparatus, and FIG. 29 is a block diagram showing pre-signal processing means constituting signal processing means.

Description of the same parts as in FIG. 17 is omitted.

AG built in the form of the seventh embodiment
The C circuit 145, the aperture 123, and the aperture control unit 124 are omitted in the ninth embodiment.

The photometric means 142 is provided for the CCD 10 for one screen.
The average value of the nine output signals is calculated and output to the CCD sensitivity control means 112 via the control means 121. The CCD sensitivity control means 112 calculates the number of pulses corresponding to the CMD multiplication factor at which the output signal of the CCD 109 becomes a set value, and
CC is synchronized with the light shielding period (reading period) of CD109.
The calculated number of pulses are output to D109.

(Operation) The user operates the mode switching means 13
A desired mode (normal light / special light mode) is selected by operating, for example, a mode changeover switch that constitutes 5. From the surface sequential light source device 122A, the rotation filter 129 is operated by the rotation filter switching mechanism 131 in accordance with the selected mode, and illumination light corresponding to the mode enters the rear end face of the light guide 115 via the rotation filter 129. Then, the living tissue is sequentially irradiated with illumination light. Since the aperture is not built in the surface sequential light source device 122A,
The intensity of the illumination light emitted from the end of the endoscope 102 is constant.

In the normal light mode, a video signal obtained by imaging the special light such as auto-fluorescence by the CCD 109 from the living tissue in the sequential light mode (red, blue, green) in the special light mode is sent to the signal processing means 114A. Is entered. Signal processing means 114
In A, an output signal from the CCD 109 is processed, and an observation image is displayed on the monitor 105.

When a subject (living tissue) having a certain brightness is imaged by the CCD 109, the S / N (FIG. 22) and the output value (FIG. 23) are obtained according to the CMD multiplication factor of the CCD 109. The average value of the output signals of the CCD 109 for one screen is calculated by the photometric unit 142, and
It is output to the sensitivity control means 112. The CCD sensitivity control means 112 calculates the number of pulses corresponding to the CMD multiplication factor of the CCD 109 at which the output signal becomes the brightness of the monitor 105 arbitrarily set by the user.
Is output to the CCD 109. That is, processor 1
If the output value of 03A is smaller than the set value, the CCD 10
9, the output of the processor 103A is larger than the set value.
Automatic control is performed so that the D multiplication factor becomes small. Therefore, the user can set the monitor 10 that he / she has set to an arbitrary value.
An image with a brightness of 5 can always be observed.

Further, especially when the subject is weak light, the CMD multiplication factor of the CCD 109 is automatically increased. Therefore, as can be seen from FIG. 22, for example, the CMD multiplication factor is larger than when the CMD multiplication factor is small. , The S / N is improved, so that a good observation image can be obtained.

Since the output signal from the output stage of the processor 103A is amplified by increasing the CMD multiplication factor of the CCD 109, noise is reduced as compared with the case where the output signal from the CCD 109 is electrically amplified. The influence is small, so that an image with a higher S / N is obtained.

(Effect) By automatically controlling the CMD multiplication factor of the CCD according to the brightness of the subject, it is possible to obtain an observation image with good image quality (high S / N) and appropriate brightness. Further, the configuration of the light source device can be simplified.

Note that additions, modifications, and the like in this embodiment are the same as those in the seventh embodiment.

In the present embodiment, in the normal light / special light mode, the CCD 105 is used to keep the brightness of the monitor 105 constant.
Although the CMD multiplication factor of 109 is changed, the configuration may be such that the irradiation intensity on the living tissue is changed by controlling the aperture of the light source in the normal light mode as in the first embodiment.

(Tenth Embodiment) This embodiment is directed to
In normal light observation and special light observation, the CMD multiplication factor is automatically changed, and in special light observation, + long exposure is performed.

In the ninth embodiment, the normal light mode (normal light observation) and the special light mode (special light observation) have the same exposure time.

On the other hand, in the tenth embodiment, the exposure time is set longer in the special light mode than in the normal light mode.
This realizes a higher S / N than the ninth embodiment.

Therefore, a rotary filter (second filter set) is formed as shown in FIG. 24, and the timing of driving the CCD in the special light mode is set as shown in FIG.

(Structure) The description of the parts common to the ninth embodiment is omitted.

This embodiment differs from the ninth embodiment only in the configuration of the rotary filter 129A and the timing of driving the CCD in the special light mode.

(Operation) The operation in the special light mode will be described. The operation in the normal light mode is the same as in the ninth embodiment.

The excitation light (from ultraviolet to blue light in this embodiment) emitted from the lamp 127 is supplied to the second filter set 1.
34A, the filter 134 in this embodiment.
Excitation light that has passed through the aA is intermittently applied to the living tissue.
The irradiation time (exposure time) is about three times that of the ninth embodiment. The filter 134c is not irradiated in this embodiment. CCD1
In step 09, the auto-fluorescence imaged during the period in which the living tissue is irradiated with the excitation light is received, and the stored signal charges are read out during the G2 light-shielding period (reading period). The obtained output signal is subjected to signal processing. Input to the means 114A. The signal processing unit 114A performs signal processing, and displays a special light observation image on the monitor 105.

Here, the long-time exposure of the CCD 109 and C
The S / N and brightness of an observation image (autofluorescence image in this embodiment) displayed on the monitor 105 when the MD multiplication factor is increased will be described.

In the tenth embodiment, the exposure time T ′ is about three times the exposure time T of the ninth embodiment. Further, the CMD multiplication factor of the CCD 109 is set to 3 times and 10 times. 26 and 27 show the relationship between the plate surface illuminance, the S / N, and the output value obtained in that case.

When a subject (living tissue) having a certain brightness is imaged by the CCD 109 with the exposure time extended, the CCD 109
According to the CMD multiplication factor of 109, the S / N (FIG. 26) and the output value (FIG. 27) are obtained. Comparing with the same CMD multiplication factor, it can be seen that the S / N and the output value are longer when the exposure time is extended than when the exposure time is longer than in the ninth embodiment. The average value of the output signals of the CCD 109 for one screen is calculated by the photometric means 142 and output to the CCD sensitivity control means 112 via the control means 121. The CCD sensitivity control means 112 outputs a constant output signal arbitrarily set by the user. Brightness C
The number of pulses corresponding to the CMD multiplication factor of the CD 109 is calculated and output from the CCD sensitivity control means 112 to the CCD 109. That is, when the output value of the processor 103A is smaller than the set value, the CMD multiplication factor of the CCD 109 is increased, and when the output value of the processor 103A is larger than the set value, the CMD multiplication factor of the CCD 109 is automatically decreased. Controlled. Therefore, an observation image of the brightness of the monitor set by the user to an arbitrary value can always be observed.

Further, especially when the subject is weak light, the CMD multiplication factor of the CCD 109 is automatically increased. Therefore, as can be seen from FIG. 26, for example, the CMD multiplication factor is increased as compared with the case where the CMD multiplication factor is small. It can be seen that the S / N is significantly improved by performing the exposure for a long time.

Since the output signal from the output stage of the processor 103A is amplified by increasing the CMD multiplication factor of the CCD 109, the noise is smaller than when the output signal from the CCD 109 is electrically amplified. The influence is small, so that an image with a higher S / N is obtained.

(Effect) When the special light mode (special light observation) is performed, good image quality (high S) can be obtained by automatically controlling the CMD multiplication factor of the CCD according to the level of weak light.
/ N) and an observation image with appropriate brightness can be obtained. Further, an observation image with a higher S / N can be obtained by extending the exposure time. Further, the configuration of the light source device can be simplified.

The addition and modification of this embodiment are described in Embodiment 8.
Is the same as

In this embodiment, in the normal light / special light mode, the CCD 105 is used to keep the brightness of the monitor 105 constant.
Although the CMD multiplication factor of 109 is controlled, a configuration may be employed in which the irradiation intensity on the living tissue is changed by controlling the aperture of the light source in the normal light mode as in the first embodiment.

It should be noted that embodiments and the like constituted by, for example, partially combining the above-described embodiments and the like also belong to the present invention.

[Supplementary Notes] An endoscope having a solid-state imaging device with variable sensitivity;
A signal processing device that performs signal processing on an output signal from the solid-state imaging device, and an endoscope device that has a light source device that irradiates illumination light to a subject, wherein the endoscope device includes a sensitivity control unit that controls sensitivity of the solid-state imaging device. Endoscope device characterized by the following.

[0219] 2. 2. The apparatus according to claim 1, wherein the sensitivity control means is provided in a signal processing device, and the sensitivity of the solid-state imaging device is set according to a type of the endoscope or a characteristic of each solid-state imaging device. Endoscope device.

[0219] 3. The endoscope apparatus according to claim 1, wherein the sensitivity control unit controls the sensitivity of the solid-state imaging device in accordance with a signal from a designation unit that designates the sensitivity of the solid-state imaging device.

[0220] 4. The endoscope is provided with information generating means for generating information representing characteristics of the endoscope, and the sensitivity control means is controlled in accordance with information from the information generating means. Endoscope device.

5. The endoscope apparatus according to claim 1, wherein the sensitivity control unit is controlled according to operation information of the light source device.

6. The endoscope apparatus according to claim 1, wherein the sensitivity control unit is controlled according to a driving condition of the solid-state imaging device.

[0223] 7. The endoscope apparatus according to claim 1, wherein the sensitivity control unit is controlled according to an output signal from the signal processing device.

8. The endoscope is provided with information generating means for generating correction information of the sensitivity of the solid-state imaging device, and based on information from the information generating means, a signal correcting means for correcting an output signal of the solid-state imaging device. The endoscope apparatus according to claim 1, further comprising:

9. Endoscope having a solid-state imaging device capable of controlling sensitivity by multiplying electrons by supplying a pulse-like drive signal, and having information generating means for generating information representing characteristics of the endoscope And a signal processing device for signal processing an output signal from the solid-state imaging device, and an endoscope device having a light source device for irradiating illumination light to a subject, wherein the solid-state imaging device according to information from the information generating means. An endoscope apparatus comprising a drive signal generating means for controlling at least one of a pulse number and a pulse waveform of a pulse-like drive signal supplied to an element.

10. An endoscope having a solid-state imaging device capable of controlling sensitivity by multiplying electrons by supplying a pulsed drive signal, a signal processing device for performing signal processing on an output signal from the solid-state imaging device, and In an endoscope apparatus having a light source device for irradiating the illumination light, at least one of the number of pulses of the same pulse-shaped signal to be supplied to the solid-state imaging device and a pulse waveform are set based on characteristics of the endoscope. An endoscope apparatus comprising: a driving signal generating means.

(11) The endoscope apparatus according to attachments 9 and 10, wherein the feature of the endoscope is information based on a lens aperture of the endoscope and the number of light guides.

12. The endoscope apparatus according to Supplementary Notes 9 and 10, wherein the feature of the endoscope is information based on an observation use.

(Supplementary notes 1, 2, 3, 4, 9, 10, 11,
12 backgrounds) Described in the text.

13. An endoscope having a solid-state imaging device capable of controlling sensitivity by multiplying electrons by supplying a pulsed drive signal, a signal processing device for performing signal processing on an output signal from the solid-state imaging device, and In an endoscope device having a light source device for irradiating the illumination light, at least one of a pulse number and a pulse waveform of a pulse-like drive signal supplied to the solid-state imaging device is controlled according to operation information of the light source device. An endoscope apparatus comprising a drive signal generating means.

14. The operation information of the light source device is information based on a light amount of a lamp.
Endoscope device.

15. The endoscope apparatus according to appendix 13, wherein the operation information of the light source device is information based on a stop position of the light source device.

(Background of Supplementary Notes 5, 13, 14, and 15) In the endoscope device, a light source device using a halogen lamp, a xenon lamp, or an LED is used. Since the amount of light varies depending on the type of lamp, an LED with a particularly small amount of light
In the case where is used, an appropriate amount of exposure could not be obtained, resulting in a dark observation image. Further, when the aperture in the light source device is fully opened, the amount of light irradiated on the subject is insufficient, and this also results in a dark observation image.

Accordingly, it is an object of the present invention to provide an endoscope apparatus in which the sensitivity of the solid-state imaging device is controlled in accordance with the operation information of the light source to obtain an appropriate exposure amount.

16. An endoscope provided with a solid-state image sensor capable of controlling sensitivity by multiplying electrons by supplying a pulse-like drive signal, a signal processing device for performing signal processing on an output signal from the solid-state image sensor, and a subject In the endoscope device having a light source device that irradiates the illumination light to the, according to the driving conditions of the solid-state imaging device, at least one of the pulse number of the pulse-like drive signal supplied to the solid-state imaging device, pulse waveform An endoscope apparatus comprising a drive signal generating means for controlling.

[0236] 17. The endoscope apparatus according to appendix 16, wherein the driving condition of the solid-state imaging device is information based on an electronic shutter operation.

18. Supplementary note 1 wherein the driving condition of the solid-state imaging device is information based on an imaging rate.
6. The endoscope device of 6.

(Background of Supplementary Notes 6, 16, 17, and 18) When observing a fast-moving subject or capturing a still image with the endoscope apparatus, the solid-state image pickup device performs an electronic shutter operation.
At this time, the irradiation light amount is increased in order to make the exposure amount appropriate. However, if the electronic shutter operation is performed in a state where the aperture for adjusting the irradiation light amount is fully opened, the exposure amount becomes insufficient.
The result is a dark image. AGC can compensate for the lack of exposure, but the noise increases.

Therefore, it is an object of the present invention to provide an endoscope apparatus in which the sensitivity of the solid-state imaging device is controlled according to the driving state of the solid-state imaging device, and an observation image with less noise is obtained.

19. An endoscope having a solid-state imaging device capable of controlling sensitivity by multiplying electrons by supplying a pulse-like drive signal, a signal processing circuit for processing an output signal from the solid-state imaging device, and In an endoscope device having a light source device that irradiates the illumination light, in accordance with an output signal from the signal processing circuit, at least one of the number of pulses of a pulse-like drive signal to be supplied to the solid-state imaging device and a pulse waveform. An endoscope apparatus comprising a drive signal generating means for controlling.

(Background of Supplementary Notes 7 and 19) The light source device of the endoscope apparatus has a light amount adjusting mechanism using aperture blades, and the signal processing circuit has an AGC (Auto Gain Control).
l) There was a circuit.

By controlling the sensitivity of the solid-state imaging device in accordance with the output of the signal processing circuit for processing the output signal of the solid-state imaging device, an observation image having appropriate brightness can be obtained without using the light amount adjusting mechanism of the light source device or the AGC. An object of the present invention is to provide an endoscope that obtains the following.

20. An information generating means having a solid-state imaging device capable of controlling sensitivity by multiplying electrons by supplying a pulse-like drive signal, and generating information representing an electron multiplication factor for each pixel of the solid-state imaging device An endoscope having a signal processing circuit for processing an output signal from the solid-state imaging device, and a light source device for irradiating the subject with illumination light, based on information from the information generating means. An endoscope apparatus having signal correction means for correcting an output signal of the solid-state imaging device.

(Background of Supplementary Notes 8 and 20) Since the operation of multiplying electrons of the solid-state imaging device is performed for each pixel, when sensitivity is increased, variation in image magnification for each pixel may cause deterioration in image quality. Become.

An object of the present invention is to provide an endoscope that obtains a high-quality observation image by correcting the output of a solid-state image sensor using information on the electron image magnification of each pixel of the solid-state image sensor. .

21. An endoscope having a solid-state imaging device capable of changing the electron multiplication factor and changing the sensitivity by supplying a plurality of pulsed drive signals, a signal processing device for processing an output signal from the solid-state imaging device, and A light source device that irradiates light to a subject so that the solid-state imaging device forms a subject image, and a sensitivity control that variably supplies a sensitivity control pulse to the solid-state imaging device and controls an electron multiplication factor of the solid-state imaging device. And an endoscope device.

22. An endoscope having a solid-state imaging device capable of changing the electron multiplication factor and changing the sensitivity by supplying a plurality of pulse-like drive signals; a signal processing device for processing an output signal from the solid-state imaging device; A light source device that irradiates the subject with light and special light in a specific wavelength region with variable intensity, observation in a normal light mode with the white light, and means for switching between observation in the special light mode with the special light in the specific wavelength region, An endoscope apparatus comprising: a sensitivity control unit that varies a sensitivity control pulse and supplies the variable to the solid-state imaging device to control an electron multiplication factor of the solid-state imaging device.

23. An endoscope having a solid-state imaging device capable of changing the electron multiplication factor and changing the sensitivity by supplying a plurality of pulse-like drive signals, and an optical device that emits light to a subject so that the solid-state imaging device forms a subject image. A surface sequential light source device for sequentially irradiating the solid-state imaging device, sensitivity control means for varying the sensitivity control pulse and supplying the solid-state imaging device with an electron multiplication factor, and a signal output from the solid-state imaging device. Pre-signal processing means for processing, field-sequential signal synchronizing means for synchronizing the field-sequential signal output from the pre-signal processing means, post signal for processing a signal output from the synchronizing means to generate a television signal An endoscope apparatus comprising: signal processing means having processing means.

24. The sensitivity control unit, a designation signal from the designation unit, an information signal supplied from the connected endoscope and indicating characteristics of the endoscope, an operation information signal of the light source device, a signal indicating a driving condition of the solid-state imaging device, The endoscope apparatus according to claim 1, wherein the endoscope apparatus is controlled in accordance with at least one of output signals from the signal processing device.

25. 3. The endoscope apparatus according to claim 2, wherein the sensitivity control unit performs different control between observation in a normal light mode and observation in a special light mode.

26. 3. The endoscope apparatus according to claim 1, wherein the sensitivity control unit sets at least one of a pulse number and a pulse waveform of a pulse signal supplied to the solid-state imaging device. .

27. The endoscope apparatus according to claim 4, wherein the information indicating the characteristics of the connected endoscope is at least one of a lens aperture of the endoscope and the number of light guides.

28. The endoscope apparatus according to claim 4, wherein the operation information of the light source device is at least one of information based on a light amount of a lamp and information based on an aperture.

29. The endoscope apparatus according to claim 4, wherein the driving condition of the solid-state imaging device is at least one of information based on an electronic shutter and information based on an imaging rate.

30. 3. The sensitivity control unit according to claim 1, wherein the information indicating the characteristics of the connected endoscope is controlled by an information signal input from the input unit and indicating the characteristics of the endoscope. Endoscope device.

31. 3. The endoscope apparatus according to claim 1, wherein the signal processing unit includes a unit that amplifies a signal gain when an output signal from the solid-state imaging device is lower than a set value.

32. The sensitivity control means is provided in a signal processing device, and the sensitivity of the solid-state imaging device is set according to a type of the endoscope or a characteristic of each solid-state imaging device. 3. The endoscope device according to 2.

33. 3. The light source device according to claim 1, wherein the light source device has a light amount adjusting mechanism using a diaphragm blade.
An endoscope apparatus according to claim 1.

34. 3. The light source device according to claim 2, wherein the light source device irradiates the subject with light in a plane-sequential manner, and when observing in the special light mode, the exposure time is longer than in the normal light mode. Endoscope device.

35. The endoscope apparatus according to claim 2, wherein the observation in the special light mode is at least one of autofluorescence observation, drug fluorescence observation, infrared fluorescence observation, and reflected light observation of a specific wavelength. .

36. When the light source device is used for observation in the special light mode, the light in the ultraviolet to blue range is converted to light in the ultraviolet range, light in the blue range, light of a specific wavelength in the visible range corresponding to the PDD drug, and specification of the visible to near-infrared range. 3. The endoscope device according to claim 2, wherein the endoscope device is at least one of light having a wavelength and light having a specific wavelength in a near-infrared region corresponding to infrared fluorescence.

37. The endoscope apparatus according to claim 1, wherein the endoscope is a frame sequential type.

38. The endoscope has two solid-state imaging devices at its tip, one of which is a solid-state imaging device having no electron multiplying function for performing imaging with ordinary light, and the other is an electronic multiplication device for performing imaging with special light. 3. The endoscope apparatus according to claim 2, wherein the endoscope apparatus is a solid-state imaging device having a double function.

39. The endoscope has two solid-state imaging devices internally provided at its tip, one of which is a solid-state imaging device that performs imaging with ordinary light, and the other is a solid-state imaging device that performs imaging with special light. The endoscope apparatus according to claim 2, wherein

[0265]

As described above, according to the present invention, an endoscope having a solid-state imaging device with variable sensitivity, a signal processing device for processing an output signal from the solid-state imaging device,
In an endoscope apparatus having a light source device for irradiating an object with illumination light, sensitivity control means for controlling the sensitivity of the solid-state imaging device is provided. An image is obtained.

This sensitivity control means also has a feature that the sensitivity can be freely controlled by the amplitude and the number of the sensitivity control pulses. By controlling the sensitivity, there is no generation of noise due to multiplication, no cooling is required, and high sensitivity is achieved. Since a solid-state imaging device can be realized, an endoscope with good image quality and excellent insertability can be realized.

The sensitivity control means is provided in a signal processing device, and the sensitivity of the solid-state imaging device is set according to the type of the endoscope or the characteristics of each solid-state imaging device. Observed images with appropriate brightness can be obtained regardless of the type of endoscope or the characteristics of each solid-state imaging device.

The sensitivity control means controls the sensitivity of the solid-state imaging device in response to a signal from the designation means for designating the sensitivity of the solid-state imaging device. Observed images with appropriate brightness can be obtained regardless of the characteristics of each element.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an overall configuration of an endoscope apparatus according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a pre-signal processing unit constituting the signal processing unit.

FIG. 3 is a block diagram showing a configuration of a frame sequential signal synchronizing unit and a post signal processing unit constituting the signal processing unit.

FIG. 4 is a diagram showing various types of endoscopes used in the embodiment.

FIG. 5 is a diagram showing an application of an endoscope and the like.

FIG. 6 is an operation explanatory diagram.

FIG. 7 is a block diagram showing an overall configuration of an endoscope apparatus according to a second embodiment of the present invention.

FIG. 8 is a block diagram showing an overall configuration of an endoscope apparatus according to a third embodiment of the present invention.

FIG. 9 is a block diagram showing an overall configuration of an endoscope apparatus according to a fourth embodiment of the present invention.

FIG. 10 is a block diagram showing a detailed configuration of a video signal processing unit.

FIG. 11 is a block diagram showing an overall configuration of an endoscope apparatus according to a fifth embodiment of the present invention.

FIG. 12 is a block diagram showing a detailed configuration of a pre-signal processing unit.

FIG. 13 is a block diagram illustrating an overall configuration of an endoscope apparatus according to a sixth embodiment of the present invention.

FIG. 14 is a block diagram showing a detailed configuration of a pre-signal processing unit.

FIG. 15 is a diagram showing a detailed configuration of a CCD.

FIG. 16 is an explanatory diagram showing operations at the time of normal sensitivity and at the time of electron doubling operation.

17 to 23 relate to a seventh embodiment of the present invention, and FIG. 17 is a block diagram showing a schematic configuration of an endoscope apparatus.

FIG. 18 is an explanatory diagram showing a configuration of two filter sets provided in a rotary filter.

FIG. 19 is a block diagram showing pre-signal processing means constituting the signal processing means.

FIG. 20 is a block diagram showing a frame sequential synchronizing unit and a post signal processing unit constituting the signal processing unit;

FIG. 21 is a timing chart of driving a CCD.

FIG. 22 is a graph showing the relationship between the illuminance of the CCD surface and the S / N ratio.

FIG. 23 is a graph showing the relationship between the illuminance of the CCD surface and the output voltage.

24 to 27 relate to an eighth embodiment of the present invention, and FIG. 24 shows a configuration of a rotary filter.

FIG. 25 is a timing chart in a special light mode driven by a CCD.

FIG. 26 is a graph showing the relationship between CCD plate surface illuminance and S / N (long exposure).

FIG. 27 is a graph showing a relationship between a plate surface illuminance of a CCD and an output voltage (long exposure).

28 and 29 relate to a ninth embodiment of the present invention, and FIG. 28 is a block diagram showing a schematic configuration of an endoscope apparatus.

FIG. 29 is a block diagram showing pre-signal processing means constituting the signal processing means.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Endoscope apparatus 2 ... Endoscope (endoscope) 3 ... Processor 4 ... Signal processing apparatus 5 ... Monitor 6 ... Insertion part 7 ... Tip part 9 ... CCD 11 ... CCD drive means 12 ... CCD sensitivity control means 14 ... video signal processing means 15 ... light guide 17 ... pre-signal processing means 18 ... frame sequential signal synchronizing means 19 ... post signal processing means 21 ... control means 24 ... aperture control means 25 ... RGB rotation filter control means 26 ... control means 27 ... Lamp 29 ... RGB rotation filter 30 ... Motor 31 ... CDS circuit 32 ... LPF 33 ... Clamp circuit 35a, 35b ... Photo coupler 36 ... White balance correction circuit 37 ... Color tone adjustment circuit 38 ... Gamma correction circuit 39 ... Enlargement circuit 40 ... Contour Emphasis circuit 48 ROM

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[Procedure amendment]

[Submission Date] June 7, 2000 (2000.6.7)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0110

[Correction method] Change

[Correction contents]

The endoscope 102 has an elongated insertion portion 106 to be inserted into a body cavity, and a distal end portion 107 of the insertion portion 106 has an objective lens 108 for forming an image of a subject, and an objective lens 108 An image sensor as a solid-state imaging device, for example, a charge-coupled device (abbreviated as CCD)
The CCD 109 is connected via signal lines to CCD driving means 111 and CCD impression control means 112 provided in the signal processing device 104 in the processor 103. The CCD driving means 111 and CCD impression control means 112 Exposure, multiplication of generated charges, and readout control are performed by the drive signal and the sensitivity control signal generated in step (1).
Further, the image sensor may be a CMOS sensor. CC
On the front surface of D109, a filter 110 that transmits only a specific wavelength region is arranged. Filter 110
Has a spectral transmittance characteristic of transmitting a wavelength band of auto-fluorescence emitted from a living tissue and cutting (not transmitting) excitation light.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

First, when the normal light mode (normal light observation) is performed, the rotation filter 129 is set to the first filter set 1.
Reference numeral 33 is arranged on the illumination light path, and the CMD multiplication factor of the CCD 109 is set to a fixed value. The set value (fixed value) for the normal light mode of the CMD multiplication factor of the CCD 109 is the endoscope 102.
Is transmitted from the ROM 170 when connected to the processor 103.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

The CCD sensitivity control means 112 includes the control means 1
CCD 109 transmitted from ROM 170 via
And calculates the number of pulses corresponding to the CMD multiplication factor (fixed value) in the normal light mode,
The calculated number of pulses are output to the CCD 109 in synchronization with the exposure / light shielding (readout period) of the CCD 109.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

The illumination light emitted from the lamp 127
By passing through the filter set 133, R (red), G
(Green), B (blue) surface-sequential illumination light is sequentially irradiated on the living tissue, and the reflected light is sequentially imaged by the CCD 109.
The G and B image signals (video signals) are input to the signal processing unit 114, and a normal light observation image is displayed on the monitor 105.

Continued on the front page (72) Inventor Kazunari Nakamura 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Industrial Co., Ltd. (72) Inventor Sakae Takehata 2-43-2 Hatagaya, Shibuya-ku, Tokyo Ori (72) Inventor Katsuichi Imaizumi 2-43-2, Hatagaya, Shibuya-ku, Tokyo Orimpus Optical Industries, Ltd. (72) Takayuki Hanawa 2-43-2, Hatagaya, Shibuya-ku, Tokyo Olympus Optical Co., Ltd.

Claims (3)

[Claims] 1. An endoscope having a solid-state imaging device having a variable sensitivity, a signal processing device for processing an output signal from the solid-state imaging device, and a light source device for irradiating illumination light to a subject. An endoscope apparatus, comprising: a mirror device; a sensitivity control unit configured to control sensitivity of the solid-state imaging device. 2. The apparatus according to claim 1, wherein the sensitivity control unit is provided in a signal processing device, and the sensitivity of the solid-state imaging device is set according to a type of the endoscope or a characteristic of each solid-state imaging device. The endoscope device according to claim 1. 3. An endoscope according to claim 1, wherein said sensitivity control means controls the sensitivity of said solid-state imaging device in accordance with a signal from designating means for designating the sensitivity of said solid-state imaging device. apparatus.