JP2003018467A - Charge multiplier type solid-state electronic imaging apparatus and its control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a charge multiplier type CCD that suppresses a dark current. SOLUTION: The signal charge stored in a photo diode 2 is shifted to a vertical transfer line 3 and transferred in a row direction. The signals charge stored in photo diodes 2 of even number rows is given to a 1st horizontal transfer line 4 through which the charge is transferred horizontally. The signal charge stored in photo diodes 2 of odd number rows is given to a 2nd horizontal transfer line 5 through which the charge is transferred horizontally. Since the two horizontal transfer lines 5, 6 are used to transfer the signal charge, the transfer time can be decreased and the dark current can be suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charge multiplication type solid state electronic imaging device, an operation control method thereof and an endoscope apparatus using such a charge multiplication type solid state electronic imaging device.

[0002]

BACKGROUND OF THE INVENTION In a solid-state electronic image pickup device such as a CCD, a current flows (dark current, dark noise) regardless of the incidence of light. Such a dark current is also generated in a charge multiplication type solid-state electronic image pickup device that can transfer accumulated signal charges while multiplying them. Particularly, in the charge multiplication type solid-state electronic image pickup device, since the accumulated signal charges are multiplied, the signal charges that generate the dark current are also multiplied.

Therefore, it is very important to reduce the dark current in the charge multiplication type solid state electronic image pickup device.

[0004]

DISCLOSURE OF THE INVENTION The present invention aims to reduce dark current.

In the charge multiplication type solid-state electronic image pickup device according to the first aspect of the present invention, a large number of photoelectric conversion elements (for example, a large number of photoelectric conversion elements provided in the vertical direction and the horizontal direction) which accumulate signal charges in accordance with the amount of incident light. And a read-out means (vertical transfer path, horizontal transfer path) for reading out the signal charge accumulated in the photoelectric conversion element for each of the plurality of areas, It is characterized in that it comprises a charge multiplication stage which is provided corresponding to the reading means and transfers the signal charges read from the reading means while multiplying the signal charges for each region.

The first aspect of the present invention also provides an operation control method suitable for the solid-state electronic image pickup device. That is, according to this method, in a solid-state electronic image pickup device having a light receiving region provided with a large number of photoelectric conversion elements for accumulating signal charges according to the amount of incident light, the light receiving region is divided into a plurality of regions, A read circuit is provided corresponding to the area, a charge multiplication stage is provided corresponding to the read circuit, and the signal charge accumulated in the photoelectric conversion element is read from the read circuit for each of the plurality of areas. The signal charges read from the reading circuit are transferred while being multiplied for each region.

According to the first aspect of the invention, the reading means (reading circuit) is provided in correspondence with the region where the light receiving region is divided into a plurality of regions. The signal charges accumulated in the photoelectric conversion elements in a plurality of regions can be read simultaneously for each region. The signal charges read out for each of the plurality of regions are transferred while being multiplied by the charge multiplication stage provided for each of the plurality of regions.

Since the read-out means and the charge multiplication stage are provided corresponding to a plurality of regions, the signal charges accumulated in the photoelectric conversion element can be read out for each of the plurality of regions. The signal charges can be read out relatively quickly. Since the dark current increases in proportion to the read time, the dark current can be suppressed by shortening the signal charge read time.

If a large number of the photoelectric conversion elements are arranged in the row direction and the column direction, the read-out means outputs the signal charges accumulated in the photoelectric conversion elements included in the area in the row direction (vertical direction). From the horizontal transfer path provided corresponding to the area in which the signal charges transferred in the vertical transfer path are transferred in the horizontal direction for each signal charge accumulated in the photoelectric conversion element in the area. Will be composed. The length of the transfer path of the horizontal transfer path can correspond to the horizontal length of each area, or can correspond to the horizontal length of the light receiving area. The charge multiplication stage is
It is provided corresponding to the horizontal transfer path.

The read means corresponds to, for example, an odd-row vertical transfer path and an odd-row vertical transfer path for transferring the signal charges accumulated in the photoelectric conversion elements of the odd rows in the row direction (vertical direction). Provided for the horizontal transfer path for the odd rows, which transfers the signal charges transferred in the vertical transfer path for the odd rows in the horizontal direction, and for the even rows that transfers the signal charges accumulated in the photoelectric conversion elements in the even rows in the row direction. It may be a horizontal transfer path for even rows which transfers the signal charges transferred in the vertical transfer path and the vertical transfer path for even rows in the horizontal direction.

In this case, the charge multiplication stage is an odd-row charge multiplication stage for multiplying and transferring the signal charges accumulated in the odd-row photoelectric conversion elements transferred through the odd-row horizontal transfer path. The charge multiplication stage for even rows may be configured to multiply and transfer the signal charges accumulated in the photoelectric conversion elements of the even rows transferred through the horizontal transfer paths for even rows.

It is possible to further include a generation means for generating a video signal representing an image of one frame based on the signal charges transferred through the charge multiplication stage while being multiplied in each of the plurality of divided regions.

A video signal representing an image of one frame can be obtained on the basis of the signal charges obtained separately for each region.

In response to the adjustment command, means for adjusting the charge amount of the signal charges transferred through the charge multiplication stage while being multiplied in each of the plurality of divided regions to a predetermined ratio (increase). (Double drive pulse adjustment, A / D gain adjustment, software adjustment, etc.) may be further provided.

If there are a plurality of read-out means and a plurality of charge multiplication stages, the amount of signal charges may change during the transfer of the read-out means and charge multiplication stages. Since the charge amount of the signal charge can be adjusted so as to have a predetermined ratio (for example, to be equal), a change in the signal charge amount during the transfer of the reading means and the charge multiplication stage can be corrected.

The data used for the adjustment by the adjusting means can be obtained from at least one of the memory storing the adjustment data and the receiving device for receiving via the network.

When the charge multiplication type solid state electronic image pickup device is applied to an endoscope device, for example, the memory can be provided as a ROM in a video scope of the endoscope device. Further, if the endoscope apparatus is capable of communicating with the server via the network, the adjustment data is transmitted from the server so that the reception apparatus can receive the adjustment data.

An endoscope apparatus according to a second aspect of the present invention is an endoscope apparatus including a light source for illuminating a body tissue and a solid-state electronic image pickup apparatus for photographing a body tissue illuminated by the light source. The above-mentioned charge multiplication type solid-state electronic image pickup device is used for the device.

Since the charge multiplication type solid state electronic image pickup device is used for the solid state electronic image pickup device of the endoscope apparatus, the dark current output from the solid state electronic image pickup device can be suppressed and a relatively accurate diagnosis can be performed. Like

The above-mentioned light source emits, for example, excitation light that fluoresces internal tissues (for example, 430 nm to 730 nm), and light having a wavelength different from the above excitation light (for example, 730 nm).
~ 900nm near infrared light) and others.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of the present invention and shows the structure of a charge multiplication type CCD.

The CCD 1 is arranged on the right side of each column of a plurality of photodiodes (photoelectric conversion elements) 2 and photodiodes 2 arranged in rows and columns, and the signal charges accumulated in the photodiodes 2 are vertically arranged. Connected to the output side (lower side) of the vertical transfer path 3 and the first horizontal transfer path 4 and the second horizontal transfer path 4 for transferring the signal charges transferred in the vertical transfer path 3 in the horizontal direction. Horizontal transfer path 5
Is provided.

The first horizontal transfer paths 4 are connected to the vertical transfer paths 3 in even columns. The signal charges transferred from the vertical transfer paths 3 in the even columns (the signal charges accumulated in the photodiodes 2 in the even columns) are transferred in the horizontal direction. First
The signal charges transferred from the horizontal transfer path 4 are given to the first charge multiplication stage 6. A charge multiplication drive pulse is applied to the first charge multiplication stage 6, and the input signal charge is transferred while being multiplied in accordance with the applied charge multiplication drive pulse. The signal charge multiplied in the first charge multiplication stage 6 is converted into a video signal in the first FDA (floating diffusion amplifier) 8 and output from the CCD 1.

The second horizontal transfer paths 5 are connected to the vertical transfer paths 3 in odd columns. The signal charges transferred from the vertical transfer paths 3 of the odd columns (the signal charges accumulated in the photodiodes 2 of the odd columns) are transferred in the horizontal direction. Second
The signal charges transferred from the horizontal transfer path 5 are given to the second charge multiplication stage 7. The charge multiplication drive pulse is also applied to the second charge multiplication stage 7, and the input signal charge is transferred while being multiplied according to the applied charge multiplication drive pulse. The signal charge multiplied in the second charge multiplication stage 7 is converted into a video signal in the second FDA 9 and output from the CCD 1.

Since the signal charges accumulated in the photodiodes 2 in the odd-numbered columns and the signal charges accumulated in the photodiodes 2 in the even-numbered columns can be read at the same time, the reading time can be shortened and the dark current can be suppressed. become.

Further, since there are errors in the horizontal transfer path and the charge multiplication stage, the transfer rate and multiplication factor are
Not exactly the same. Therefore, the same signal charge amount is not obtained even when the reference object (white diffusion plate or the like) is imaged. In this embodiment, the amounts of signal charges obtained when the reference object is imaged can be made the same. Details will be described later.

FIG. 2 shows another configuration of the charge multiplication type CCD.

In the CCD 1 shown in FIG. 1, the first horizontal transfer paths 4 are connected to the vertical transfer paths 3 in even columns, and the second horizontal transfer paths 5 are connected to the vertical transfer paths 3 in odd columns. , Fig. 2
In the CCD 1A shown in (1), a large number of photodiodes 2 are divided into three regions in the column direction (regions 2A, 2B and 2C). A first horizontal transfer path 11, a second horizontal transfer path 14 and a third horizontal transfer path 17 are connected to each vertical transfer path 3 included in the divided area. That is, the vertical transfer path 3 included in the first area 2A
Are connected to the first horizontal transfer path 11. The vertical transfer path 3 included in the second area 2B is connected to the second horizontal transfer path 14. The vertical transfer path 3 included in the third region 2C is connected to the third horizontal transfer path 17.

The signal charges accumulated in the photodiodes 2 arranged in the first area 2A are stored in the first area 2A.
The data are transferred vertically through the vertical transfer paths 3 arranged inside and input to the first horizontal transfer path 11. The signal charge is the first
Is transferred in the horizontal direction through the horizontal transfer path 11 and is input to the first charge multiplication stage 12. The signal charges are transferred while being multiplied in the first charge multiplication stage 12. The signal charge transferred while being multiplied in the first charge multiplication stage 12 is the first FD
At A13, it is converted into a video signal and output from the CCD 1.

The signal charges accumulated in the photodiodes 2 arranged in the second region 2B are stored in the second region 2B.
The vertical transfer paths 3 arranged inside are transferred in the vertical direction and input to the second horizontal transfer path 14. The signal charge is the second
Is transferred in the horizontal direction through the horizontal transfer path 14 and is input to the second charge multiplication stage 15. The signal charges are transferred while being multiplied in the second charge multiplication stage 15. The signal charge transferred while being multiplied in the second charge multiplication stage 15 is the second FD
At A16, it is converted into a video signal and output from the CCD 1.

The signal charges accumulated in the photodiodes 2 arranged in the third region 2C are
The vertical transfer paths 3 arranged inside are transferred in the vertical direction and input to the third horizontal transfer path 17. The signal charge is the third
Is transferred in the horizontal direction through the horizontal transfer path 17 and is input to the third charge multiplication stage 18. The signal charges are transferred while being multiplied in the third charge multiplication stage 18. The signal charge transferred while being multiplied in the third charge multiplication stage 18 is the third FD
At A19, it is converted into a video signal and output from the CCD 1.

As described above, the signal charge accumulated in the photodiode 2 in the first region 2A, the signal charge accumulated in the photodiode 2 in the second region 2B and the photodiode in the third region 2C. It is possible to read out each signal charge accumulated in No. 2. Since the signal charge can be read out quickly, dark current can be suppressed. Also in the case shown in FIG. 2, by adjusting the charge multiplication pulse given to the first charge multiplication stage 12, the second charge multiplication stage 15 and the third charge multiplication stage 18, the reference object is changed. It becomes possible to make the amounts of the signal charges obtained at the time of imaging substantially equal.

FIG. 3 is a block diagram showing the electrical construction of a fluorescence endoscope apparatus using the CCD 1 shown in FIG.

The fluorescence endoscope is a fluorescence image (narrow band) represented by fluorescence having a relatively short wavelength (about 430 nm to 530 nm) among fluorescence generated from the body tissue OB when the body tissue OB is irradiated with excitation light. A fluorescent image (referred to as a fluorescent image) and a fluorescent image (referred to as a broadband fluorescent image) represented by fluorescence having a relatively long wavelength (about 430 nm to 730 nm) and light in the near infrared wavelength region (about 750 nm to 900 nm) of the reflected light of the internal tissue OB A reflected light image represented by (referred to as an IR reflected light image) can be obtained (fluorescence observation mode). In the fluorescence observation mode, excitation light and near infrared light are alternately emitted. In addition, internal tissue OB
It is possible to obtain a reflected light image of the internal tissue (referred to as a normal reflected light image) represented by the reflected light of the internal tissue OB when the white light is irradiated on (normal observation mode). Diagnosis of the internal tissue OB is performed based on these fluorescence image, reflected light image, and the like.

The fluorescent endoscope apparatus includes an endoscope processor 20.
And endoscopic scope 50 is included. A display device 40 is connected to the endoscope processor 20. As described above, the charge multiplication CCD 1 shown in FIG. 1 is provided at the tip of the endoscope 50 as an image pickup device.

The CPU 21 controls the entire operation of the endoscope processor 20.

As described above, since the CCD 1 has the plurality of charge multiplication stages 6 and 7, the multiplication factors do not completely match. For this reason, in the fluorescent endoscope apparatus of this embodiment, when the signal charges having the same signal charge amount are transferred, the correction is performed so that the image signal of the same level is output from the CCD 1. The calibration switch 38 for giving a command for this correction processing (hereinafter referred to as calibration) is the endoscope processor 20.
It is provided in. The calibration command signal output from the calibration switch 38 is the CPU 21
To enter.

When the calibration is set by the calibration switch 38, the distal end of the endoscope 50 is covered with the calibration cap 60. The CCD driver 31 included in the endoscope processor 20 drives the CCD 1 in the endoscope scope 50, and odd-numbered-row images based on the signal charges accumulated in the odd-numbered-row photodiodes 2 from the CCD 1 as described above. The even-numbered column video signal based on the signal and the signal charges accumulated in the even-numbered column photodiodes 2 are output.

The odd-column video signal and the even-column video signal output from the CCD 1 are input to the analog / digital conversion circuit 32 in the endoscope processor 20. The analog / digital conversion circuit 32 has two analog / digital conversion circuits, a conversion circuit for an odd-numbered column video signal and a conversion circuit for an even-numbered column video signal, built-in to generate odd-numbered column image data and even-numbered column image data. Each is converted. The odd column image data and the even column image data are given to the image memory 33 and temporarily stored. The odd-numbered column image data and the even-numbered column image data stored in the image memory 33 are given to the CPU 21. The CPU 21 generates correction data (data for adjusting the level of the pulse for driving the above-described multiplication stage, the number of pulses, etc.) such that the odd-numbered column image data and the even-numbered column image data are equal. The generated correction data is stored in the correction data memory 30.

The correction data memory 30 stored in the correction data memory 30 at the time of imaging in the examination of the internal tissue OB.
The correction data is read from the CCD, and the charge multiplication drive pulse is controlled by the CCD driver 31 so that the two charge multiplication stages 6 and 7 of the CCD 1 have the same multiplication factor. Even when the odd-numbered video signal and the even-numbered video signal are divided and read out, the difference in the multiplication factors in the multiplication stages 6 and 7 can be corrected.

White light is emitted from the white light source 22. An IR filter 23A and a color filter plate 23B are provided in front of the white light source 22. Both the IR filter 23A and the color filter plate 23B can advance and retreat on the emission optical path of the white light source 22. In the fluorescence observation mode, the motor (not shown) causes the IR filter 23A to enter the emission optical path of the white light source 22, and the motor (not shown) retracts the color filter plate 23B. In the normal observation mode, the color filter plate 23B enters the emission light path of the white light source 22,
The IR filter 23A is retracted.

The IR filter 23A has a characteristic of transmitting light having a wavelength in the near infrared region of about 750 nm to 900 mn. Also in the fluorescence observation mode, when the IR filter 23A enters the emission optical path of the white light source 22, near infrared light having a wavelength of about 750 nm to 900 mn is guided to the condenser lens 24.

The color filter plate 23B has a substantially circular shape, and has a filter having a characteristic of transmitting a red light component, a filter having a characteristic of transmitting a blue light component, and a green light at every 120 degrees. A filter having a characteristic of transmitting a component is formed. In the normal observation mode, when the color filter plate 23B enters the outgoing light path of the white light source 22, the color filter plate rotates by 120 degrees at regular intervals. The red light component, the blue light component, and the green light component are guided to the condenser lens 24 at a constant cycle (a frame sequential endoscope).

The endoscope scope 50 includes a light guide 53 whose rear end is divided into two parts (excitation light guiding part 51 and white light guiding part 52). White light (including near-infrared light) collected by the condenser lens 24 is converted into white light guide section 52.
Be led to. The white light propagates through the light guide 53 and is placed at the tip of the endoscope scope 50 by the condenser lens 54.
Be led to. The white tissue illuminates the internal tissue OB.

In the fluorescence observation mode, the driver 25 controls so that the laser diode 26 emits excitation light having a wavelength of about 430 nm to 730 nm.
The excitation light emitted from the laser diode 26 is guided to the excitation light guide section 51 by the condenser lens 27. The excitation light is
The light propagates through the light guide 53 and is guided to the condenser lens 54.
The body tissue OB is illuminated by the excitation light.
In this observation mode, excitation light and near infrared light are emitted alternately.

When white light illuminates body tissue OB, reflected light is generated, and when excitation light illuminates body tissue OB, body tissue OB
Emits fluorescence. Reflected light or fluorescence is obtained by the objective lens 55
It is condensed by and is guided to the excitation light cut filter 56. The excitation light cut filter 56 has a characteristic of cutting light having a wavelength of about 420 nm or less. The light transmitted through the excitation light cut filter 56 is guided by the prism 57 onto the light receiving surface of the CCD 1 described above.

A mosaic filter 95 shown in FIG. 4 (FIG. 4 is a part of the mosaic filter 95) is arranged on the light receiving surface of the CCD 1. The mosaic filter 95 is
A narrow band filter 96 having a characteristic of transmitting light having a wavelength of about 430 nm to 530 nm and a wide band filter 97 having a characteristic of transmitting light having a wavelength of about 430 nm to 900 nm are alternately formed in the column direction. The width of each filter is one pixel (one photodiode is two) in the column direction. A narrow band filter 96 is arranged on the odd-numbered photodiodes 2 and a wide band filter 97 is arranged on the even-numbered photodiodes 2.

In the fluorescence imaging mode, the CCD 1 outputs an odd-numbered column video signal and an even-numbered column video signal representing a fluorescent image of the body tissue OB, which are input to the analog / digital conversion circuit 32 included in the endoscope processor 20. The analog / digital conversion circuit 32 converts the image data into odd-numbered column image data and even-numbered column image data, and inputs them to the image memory 33. In the image memory 33, image data representing one frame of image is generated from the odd-numbered column image data and the even-numbered column image data. By operating the addressing of the image memory 33, it is possible to generate image data representing an image of one frame. The image data output from the image memory 33 is input to the image processing circuit 34.

In the normal imaging mode, out of the reflected light of the internal tissue OB, the odd-numbered column image data obtained based on the light transmitted through the broadband filter 97 is used. The image data obtained in the normal imaging mode is the image processing circuit 34.
When inputting to, the image processing circuit 34 performs predetermined signal processing such as color correction and gamma correction, and inputs to the video circuit 35. Encoding processing such as generation of an NTSC video signal is performed from the image data input in the video circuit 35. NTS output from video circuit 35
When the C video signal is applied to the display device 40, the reflected light image is displayed on the display screen of the display device.

In the fluorescence endoscope in this embodiment, the IR reflected light obtained by reflection from the body tissue OB when the image data obtained in the fluorescence imaging mode and the near infrared light are irradiated on the body tissue OB. An image for examining the internal tissue can be generated by using the image data representing the image. As described above, the fluorescence image data and the IR reflected light image (750 nm) showing the fluorescence image (represented by fluorescence of about 430 nm to 730 nm) obtained in the fluorescence imaging mode.
From about 900 nm to about 900 nm)
The R reflected light image data is temporarily stored in the image memory 33.

From the image memory 33, fluorescence image data and I
The R reflected light image data is read out and input to the image processing circuit 34. In the image processing circuit 34, the fluorescence image data is IR
It is divided pixel by pixel by the reflected light image data. Image data representing an image resulting from the division (referred to as a first division image) is transmitted via the video circuit 35 to the NTSC (national televis
Ion system committee) is given to the display device 40 as a video signal. The IR reflected light image represents the distance from the tip of the endoscope 50 to the body tissue OB. By dividing the fluorescence image by the IR reflected light image, the difference in fluorescence intensity between normal body tissue and lesion body tissue can be displayed on the display screen of the display device 40. Distinguishing the tissue properties becomes relatively easy.

Further, in the image processing circuit 34, the color information is assigned to the fluorescence operation image obtained by dividing the narrow band fluorescence image data by one pixel by the wide band fluorescence image data, and the brightness information is assigned to the IR reflected light image data to synthesize the image. It can also be processed. The fluorescence calculation image obtained by dividing the narrow band fluorescence image data by one pixel by the wide band fluorescence image data can be considered as an image in which the tissue property is reflected in the color information. By synthesizing the color information image and the brightness information image created from the IR reflected light image, a relatively natural image of the internal tissue can be displayed on the display screen of the display device 40.

In the image processing circuit 34, color information may be assigned to the image obtained by dividing the broad band fluorescence image data by the IR reflected light image data, and brightness information may be assigned to the IR reflected light image data to be combined. Also in this case, a relatively natural image of the internal tissue is displayed on the display screen of the display device 40.

The above-mentioned mosaic on the light receiving surface of the CCD 1.
It can be easily understood that the narrow band fluorescence image data, the broad band fluorescence image data, the IR reflected light image data and the normal reflected light image data can be obtained by providing the filter 95.

FIG. 5 is a flow chart showing the processing procedure of the endoscope apparatus shown in FIG.

When the calibration switch 38 is pressed as described above (YES in step 71), the calibration mode is entered and the calibration process is executed (step 72). In the calibration process, the correction data is obtained as described above, and the obtained correction data is stored in the correction data memory 30 (step 73). After that, the process proceeds to the imaging process of the internal tissue OB. In the calibration process, since the cap 60 is fitted to the tip of the endoscope 50 as described above, it goes without saying that the cap 60 is removed when the imaging process of the internal tissue OB is performed. .

If the calibration switch 38 has not been pressed (NO in step 71) (the imaging switch (not shown) will be pressed), the correction data memory 30
Since the correction data is already stored in, the correction data stored in the correction data memory 30 is read (step 74).

When the correction data is obtained, the CCD driver is controlled so that the error of the multiplication factor of the charge multiplication stage of the CCD 1 is corrected (the charge multiplication drive pulse is output) according to the correction data as described above. 31 is set (step 75). Patient information such as a patient's name, age, and sex is input from an input device (not shown) (step 76), and an inspection command is given (step 77). When the endoscope scope 50 is inserted into the patient's body and reaches the vicinity of the body tissue OB to be examined, the body tissue OB is imaged (step 78). Video signal obtained by imaging (a video signal representing a reflected light image of the internal tissue OB when the normal observation mode is set, a video signal representing a fluorescent image generated from the internal tissue OB when the fluorescence observation mode is set, etc. ) Is obtained. The obtained video signal is converted into digital image data in the analog / digital conversion circuit 32 (step 79).

Thereafter, image processing is performed on the obtained one frame of digital image data (step 81). In the case of digital image data obtained in the normal observation mode, image processing such as color correction and gamma correction is performed. In the case of digital image data obtained in the fluorescence observation mode, as described above, the fluorescence image data is IR reflected. Processing such as division by optical image data will be performed. The image data is subjected to video processing such as generation processing of an NTSC video signal in the video circuit 35 (step 82) and given to the monitor display device 40. An image of the internal tissue OB is displayed on the display screen of the monitor display device 40 (step 83). A doctor examines the image of the body tissue OB to determine whether the body tissue OB is normal or a lesion. If the inspection is to be continued (YES in step 84), the processes of steps 78 to 83 are repeated (step 84).

The above-described transition to the calibration mode may be performed at the time of initial setting of the endoscope apparatus or may be performed at each examination.

6 and 7 show another embodiment.

FIG. 6 is a block diagram showing the electrical construction of the fluorescence endoscope apparatus. In this figure, the same parts as those shown in FIG. 3 are designated by the same reference numerals and the description thereof will be omitted. The imaging device of the fluorescence endoscope apparatus shown in FIG. 6 has the CC shown in FIG.
D1A is used. In addition, FIG. 7 is a flowchart showing a processing procedure of the fluorescence endoscope apparatus shown in FIG. Also in this figure, the same processing as the processing shown in FIG.

In the above-described embodiment, the calibration switch 38 is provided, and the correction data is obtained according to the setting of the calibration mode by the calibration switch 38. In the embodiment shown in FIG.
When the endoscope scope 50A is attached to the endoscope, the correction data is stored in the correction data memory 30 in the endoscope scope 50A.
(First correction data memory). Needless to say, the calibration switch 38 may be provided.

In the above embodiment, the CCD 1
Although the multiplication factor drive pulse is adjusted in order to correct the error between the plurality of multiplication stages in the above, in the embodiment shown in FIGS. 6 and 7, the gain of the analog / digital conversion circuit 32A should be adjusted. As a result, the error between the plurality of multiplication stages in the CCD 1A is corrected. That is, in the analog / digital conversion circuit 32A, an analog / digital conversion circuit for converting a video signal obtained based on the photodiode in the area 2A of the CCD 1A into digital image data and a photodiode in the area 2B of the CCD 1A are provided. An analog / digital conversion circuit for converting the video signal obtained based on the image signal into digital image data and an analog / digital conversion circuit for converting the video signal obtained based on the photodiode of the area 2C of the CCD 1A into digital image data are included. However, the gains of those analog / digital conversion circuits are adjusted. Also, image data representing one frame of image is generated in the image memory 33. However, hardware such as a multiplexer and a first-in-first-out (FIFO) memory for synchronization may be used without generating image data representing one frame image on the image memory 33.

The endoscope scope 50A includes a second correction data memory 58. In the second correction data memory 58, correction data for correcting the error between the plurality of multiplication stages of the CCD 1A is stored in advance. When the endoscope scope 50A is attached to the endoscope processor 20A (YES in step 91), the endoscope scope 50A
The correction data stored in the second correction data memory 58 therein is read by the correction data reading circuit 37 in the endoscope processor 20A. The read correction data is stored in the first correction data memory 30 in the endoscope processor 20A. According to the correction data, the gain of each analog / digital conversion circuit of the analog / digital conversion circuit 30A corrects the error in the multiplication stage of the CCD 1 so that the analog / digital gain control circuit 36
Is set to (step 93).

When the examination is started and the internal tissue OB is imaged, the gain of the analog / digital conversion circuit 32A is adjusted by the analog / digital gain control circuit 36 (step 94). Analog / digital conversion circuit 32A
As a result, the error in the multiplication stage of CCD 1 is corrected. Then, image data representing one frame of image is generated as described above (step 80).

FIG. 8 shows still another embodiment and is a flow chart showing the processing procedure of the fluorescence endoscope apparatus.
In this figure, the same processes as those shown in FIG. 5 are designated by the same reference numerals and the description thereof will be omitted.

In this embodiment, the endoscope device shown in FIG. 6 is used. In the endoscope apparatus shown in FIG. 6, a modem 100 is connected so that it can communicate with a server. Further, the correction processing based on the correction data is performed based on the software.

The above-mentioned correction data is stored in the server. Communication between such a server and the endoscopic device is established (step 101). The correction data is downloaded from the server to the endoscope device (step 102). The correction data obtained by downloading is stored in the correction data memory 30 in the endoscope processor 20A (step 103). Then, the communication with the server is cut off (step 104).

The body tissue OB is imaged as described above,
The image data representing the internal tissue is the area 2A, 2 of the CCD 1A.
Obtained for every B and 2C. The obtained image data is input to the image processing circuit 34. In the image processing circuit 34, CC
Processing for correcting the error in the multiplication stage of D1A is executed under the control of the CPU 21A (step 105).

As described above, the correction can be made by software instead of the hardware.

FIG. 9 shows a modification.

In the above-mentioned embodiment, by disposing the mosaic filter 95 shown in FIG. 4 on the light receiving surface of the CCD 1A, light having a wavelength range of 430 nm to 530 nm and wavelengths of 430 nm to 900 nm are provided. , But in the example shown in FIG. 9, the dichroic mirror 111
Light with wavelengths in the wavelength range of 430 nm to 530 nm and 53
It obtains light having a wavelength in the wavelength range of 0 nm to 900 nm.

At the tip of the endoscopic scope 50B, the fluorescence generated from the internal tissue OB passes through the condenser lens 55 and the excitation light cut filter 56 and is dichroic mirrored.
You are led to 111. Dichroic mirror 111 is 430nm
From 530 nm to 530 nm
It reflects light with wavelengths in the wavelength range from to 900 nm. Light having a wavelength in the wavelength range of 530 nm to 900 nm is
Light received by the first CCD 1B and having a wavelength in the wavelength range of 430 nm to 530 nm is received by the second CCD 1C.

A video signal representing an optical image having a wavelength in the wavelength range of 530 nm to 900 nm is output from the first CCD 1B, and a video signal representing an optical image having a wavelength in the wavelength range of 430 nm to 530 nm is output from the second CCD 1C. Is output.

Even with such a configuration, 530 nm to 900 nm
By adding a video signal representing an optical image having a wavelength in the wavelength region of 430 nm and a video signal representing an optical image having a wavelength in the wavelength region of 430 nm to 530 nm, broadband light having a wavelength in the wavelength region of 430 nm to 900 nm can be obtained. A video signal representing the image is obtained. Therefore, as described above, it becomes possible to execute arithmetic processing such as dividing the narrow band video signal by the wide band video signal.

FIG. 10 shows still another modified example.
It is a block diagram showing a part of electric composition of endoscope device 20B.

A CCD is not provided in the endoscope scope, but an image fiber 112 for propagating the light condensed by the condenser lens 55 is provided in the endoscope scope. The light condensed by the condenser lens 55 propagates in the image fiber 112 and is guided into the endoscope scope. The light is emitted from the rear end (on the endoscope processor side) of the image fiber 112, passes through the excitation light cut filter 56, and the condenser lens 113, and is dichroic mirror 1.
Guided to 14. The dichroic mirror 114 has the same configuration as the above-mentioned dichroic mirror 111.

53 reflected from dichroic mirror 114
Light having a wavelength in the wavelength range of 0 nm to 900 nm is emitted by the first CC
You are led to D1B. Light having a wavelength in the wavelength range of 430 nm to 530 nm transmitted through the dichroic mirror 114 is
Led to CCD 1C. The video signal output from the first CCD 1B is the first analog / digital conversion circuit.
At 115, it is converted into digital image data and given to the image memory 33. The video signal output from the second CCD 1C is the second analog / digital conversion circuit 116.
Converted into digital image data at
Given to 33.

As described above, the CCD can be provided in the endoscope processor without being provided in the endoscope scope.

Although the CCD 1 or 1A is applied to the fluorescence endoscope in the above-mentioned embodiment, it may be applied to a usual electronic endoscope. It can also be applied to so-called simultaneous endoscopes and electronic endoscopes that use complementary color filters.

[Brief description of drawings]

FIG. 1 shows the structure of a CCD.

FIG. 2 shows the structure of a CCD.

FIG. 3 is a block diagram showing an electrical configuration of the endoscope apparatus.

FIG. 4 shows a mosaic filter.

FIG. 5 is a flowchart showing a processing procedure of the endoscope apparatus.

FIG. 6 is a block diagram showing an electrical configuration of the endoscope apparatus.

FIG. 7 is a flowchart showing a processing procedure of the endoscope apparatus.

FIG. 8 is a flowchart showing a processing procedure of the endoscope apparatus.

FIG. 9 shows a part of the configuration of the endoscope.

FIG. 10 is a block diagram showing a part of an electrical configuration of the endoscope processor.

[Explanation of symbols]

1,1A, 1B, 1C CCD 2 photodiode 3 Vertical transfer path 4,5,11,14,17 Horizontal transfer path 6,7,12,15,18 Charge multiplication stage 20, 20A, 20B endoscope processor 21,21A CPU 30 Correction data memory 31 CCD driver 32 analog / digital conversion circuit 33 Image memory 34 Image processing circuit 36 A / D gain control circuit 37 Correction data reading circuit 38 Calibration switch 50 endoscope scope 95 Mosaic filter 111, 114 dichroic mirror

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4C061 CC06 JJ06 JJ15 LL01 PP01                       QQ04 SS04 SS07                 4M118 AA05 AB01 AB10 BA13 CA02                       DD04 DD20 FA06 FA44 GA10                       GC14                 5C024 AX16 BX02 CX32 GX03 GY03                       GY15 GZ42

Claims (7)

[Claims] 1. A plurality of photoelectric conversion elements for accumulating signal charges according to the amount of incident light are provided, and a light receiving region divided into a plurality of regions, and the signal charges accumulated in the photoelectric conversion devices are divided into the plurality of regions. A read-out means for reading out each divided area, and a charge multiplication stage provided corresponding to the read-out means for transferring the signal charges read out from the read-out means while multiplying the signal charges in each area are provided. Charge multiplication type solid-state electronic imaging device. 2. A generation means for generating a video signal representing an image of one frame based on the signal charges transferred through the charge multiplication stage while being multiplied in each of the plurality of divided regions. 2. The charge multiplication type solid-state electronic image pickup device according to 1. 3. Means for adjusting, in response to an adjustment command, the charge amount of the signal charges transferred through the charge multiplication stage while being multiplied in each of the plurality of divided regions to a predetermined ratio. The charge multiplication type solid-state electronic imaging device according to claim 1, further comprising: 4. The charge increasing device according to claim 3, wherein the data used for adjustment by the adjusting means is obtained from at least one of a memory storing the adjustment data and a receiving device for receiving via a network. Double type solid-state electronic imaging device. 5. An endoscope apparatus comprising a light source for illuminating a body tissue and a solid-state electronic image pickup device for picking up an image of a body tissue illuminated by the light source, wherein the solid-state electronic image pickup device has a charge according to claim 1. An endoscopic device characterized by using a multiplication type solid-state electronic imaging device. 6. The endoscope apparatus according to claim 5, wherein the light source emits excitation light for generating fluorescence of body tissue. 7. A solid-state electronic imaging device having a light-receiving region provided with a large number of photoelectric conversion elements for accumulating signal charges according to the amount of incident light, wherein the light-receiving region is divided into a plurality of regions, and the divided regions are divided. And a charge multiplication stage is provided corresponding to the read circuit, and the signal charge accumulated in the photoelectric conversion element is read from the read circuit for each of the plurality of divided regions. A method for controlling the operation of a charge multiplication type solid-state electronic imaging device, which transfers the signal charges read from the read circuit while multiplying each region.