JP2004321511A - Electronic endoscope device capable of adjusting white balance - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the display of an object image based on white balance adjustment in which light source characteristics are not suitable. <P>SOLUTION: Lamp data indicating the characteristics of a lamp 24 are stored in a ROM 27 inside a processor 20. Then, when a video scope 10 is connected to the processor 20, the lamp data of the processor used at the time of the white balance adjustment of the previous time and stored in an EEPROM 14 inside the video scope 10 are read. A system control circuit 36 judges whether or not the kind of the lamp matches on the basis of the lamp data indicating the characteristics of the lamp 24 and the lamp data transmitted from the video scope 10. In the case that the kind of the lamp 24 does not match, since endoscope work is not progressed, only a part of the object image is displayed on a monitor 52. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a video scope having an image sensor and an electronic endoscope apparatus including a processor to which the video scope is connected, and more particularly to white balance adjustment for appropriately reproducing the color of a subject image.
[0002]
[Prior art]
In a conventional electronic endoscope apparatus, white balance adjustment is performed before observation in order to appropriately reproduce a color image of an observation site (for example, see Patent Document 1). Specifically, a white object (such as a white boat) is photographed through a video scope, and the ratio of R, G, and B of the R, G, and B image signals according to the primary colors is set to 1: 1: 1. The gain values of R and B are adjusted. The white balance adjustment is performed in accordance with the color temperature of the light source, that is, the spectral distribution characteristics. For example, the R and B gain values are adjusted in accordance with the light source characteristics of each of a halogen lamp, a metal halide lamp, and a xenon lamp.
[0003]
[Patent Document 1]
JP-A-6-142038 (FIGS. 11 to 16)
[0004]
[Problems to be solved by the invention]
Video scopes can be connected to the same or multiple types of processors. Therefore, if a videoscope is newly connected to a processor having a light source having characteristics different from the previous time after the white balance has been adjusted and the endoscope operation has been performed, the R and B gain values are appropriate for the light source. Therefore, the color reproducibility of the subject image deteriorates. As a result, the site cannot be properly observed, which adversely affects diagnosis, treatment, surgery, and the like.
[0005]
Therefore, an object of the present invention is to provide an electronic endoscope apparatus or the like that prevents a subject image from being displayed based on white balance adjustment that does not correspond to light source characteristics.
[0006]
[Means for Solving the Problems]
An electronic endoscope apparatus according to the present invention is an electronic endoscope apparatus including a video scope having an image sensor and a processor to which the video scope is connected, and a light source for illuminating a subject and a video scope. And a signal processing unit for performing a white balance adjustment process on an image signal corresponding to a subject image formed on the image sensor. For example, the signal processing unit adjusts the R and B gain values so that the ratio of R, G, and B of the R, G, and B image signals corresponding to the primary colors is 1: 1: 1. Once the white balance adjustment is performed, gain control is performed on the image signal based on the set R and B gain values.
[0007]
Further, the electronic endoscope apparatus includes a light source determining unit and a work progress stopping unit. The light source determining means determines a type of the light source classified according to a spectral distribution characteristic of light emitted from the light source. However, the spectral distribution characteristic of light indicates a spectrum (energy) distribution related to the wavelength of light. For example, when a halogen lamp, a metal halide lamp, or a xenon lamp can be used as a light source, the light source determination unit determines which lamp is used. When the type of the light source is different from the type of the previously used light source used at the time of the previous white balance adjustment, the work progress stop unit does not advance the endoscope operation until the white balance adjustment is performed. After the white balance is adjusted, the subject image may be normally displayed as it is.
[0008]
Since the operator cannot proceed with the endoscope operation, white balance adjustment is necessarily performed before observing a site such as the stomach. This prevents the subject image from being displayed based on the white balance adjustment according to the spectral distribution characteristics of the different light sources, and ensures that the treatment, the operation, and the like are performed with the color of the subject image faithfully reproduced.
[0009]
In order to surely notify the operator of the necessity of white balance adjustment, it is preferable to change the setting of the display method of the subject image. For this reason, it is preferable that the work progress stop unit has a video display control unit that can switch between a mask display indicating the necessity of white balance adjustment and a normal display that entirely displays the subject image. For example, the video display control means displays only a part of the subject image so as to hinder observation on the screen. In addition, in order to notify the necessity of the white balance adjustment not only with the video but also with the text information, it is preferable that the video display control means displays the text information so as to prompt the start of the white balance adjustment.
[0010]
In order to automatically display the subject image automatically after the white balance is adjusted, it is preferable that the electronic endoscope apparatus further includes a white balance completion determining unit that determines whether the white balance adjustment is completed. In this case, the video display control means switches the subject image to the normal display when the white balance adjustment is completed.
[0011]
When it is equal to the type of the light source used at the time of the previous white balance adjustment, there is no need to perform the white balance adjustment again. Is preferred.
[0012]
In order to detect the type of the previous white balance adjustment, for example, the processor preferably includes a light source data transmitting unit that transmits light source data according to the spectral distribution characteristics of the light source to the video scope. The video scope has a scope memory capable of storing light source data. When the light source data is stored in the scope memory, the light source data is used as data indicating the type of the light source at the time of the previous white balance adjustment at the next white balance adjustment.
[0013]
In order to execute the white balance adjustment when the video scope is connected to the processor, it is preferable that the light source determination unit determines whether or not the type of the light source at the time of the previous white balance adjustment matches when the video scope is connected. . If the type of light source is different, the operator performs white balance adjustment immediately after connecting the video scope.
[0014]
The processor of the electronic endoscope apparatus of the present invention is a processor of the electronic endoscope apparatus, which has an image sensor and is connected to a video scope capable of executing a white balance adjustment process, and a light source for illuminating a subject. A light source determining unit that determines the type of light source according to the spectral distribution characteristics of light emitted from the light source, and executes white balance adjustment when the type of light source is different from the type of light source used last time during the previous white balance adjustment. Work stop means for preventing the endoscope work from proceeding until the operation is completed. In addition, a video scope of the electronic endoscope apparatus according to the present invention is a video scope connectable to such a processor, and includes an imaging device that generates an image signal corresponding to a subject image, and a subject formed on the imaging device. Signal processing means for executing a white balance adjustment process on an image signal corresponding to an image.
[0015]
A video display control device for an endoscope according to the present invention is a video display control device for an electronic endoscope device including a video scope having an image sensor and capable of executing a white balance adjustment process, and a processor to which the video scope is connected. And a spectral distribution characteristic detecting means for detecting a spectral distribution characteristic of light emitted from a light source for illuminating the subject, and when the detected spectral distribution characteristic is different from the spectral distribution characteristic at the time of the previous white balance adjustment, Video display control means for executing mask display indicating the necessity of white balance adjustment.
[0016]
A video display control method for an endoscope according to the present invention is a video display control method for an electronic endoscope apparatus including a video scope having an image sensor and capable of executing a white balance adjustment process, and a processor to which the video scope is connected. If the spectral distribution characteristic of light emitted from the light source for illuminating the subject is detected, and the detected spectral distribution characteristic is different from the spectral distribution characteristic at the time of the previous white balance adjustment, the necessity of white balance adjustment is required. Characterized by executing a mask display indicating
[0017]
A program according to the present invention is a program relating to image display control in an electronic endoscope apparatus including a video scope having an image sensor and capable of executing a white balance adjustment process and a processor to which the video scope is connected. Spectral distribution characteristic detecting means for detecting the spectral distribution characteristic of light emitted from the light source for illumination, and necessity of white balance adjustment when the detected spectral distribution characteristic is different from the spectral distribution characteristic at the time of the previous white balance adjustment And a video display control means for executing a mask display indicating the above.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an electronic endoscope apparatus according to an embodiment of the present invention will be described with reference to the drawings.
[0019]
FIG. 1 is a block diagram of the electronic endoscope apparatus according to the present embodiment.
[0020]
The electronic endoscope apparatus includes a video scope 10 having a CCD 12, and a processor 20 for processing an image signal read from the CCD 12. The video scope 10 is detachably connected to the processor 20, and a keyboard 50 is connected to the processor 20 together with a monitor 52. The videoscope 10 is connected to the processor 20 when starting an operation, an examination or the like.
[0021]
When power is supplied to the lamp 24 from the lamp power supply 11 including the lamp control unit 11A, the lamp 24 is turned on. The light emitted from the lamp 24 is incident on the incident end 13a of the optical fiber bundle 13 provided in the video scope 10 via a condenser lens (not shown) and a stop 22. The optical fiber bundle 13 transmits the light emitted from the lamp 24 to the distal end side of the video scope 10 having the observation site, and the light passing through the optical fiber bundle 13 is emitted from the emission end 13b. Thereby, light is irradiated to the observation site.
[0022]
The light reflected by the observation site reaches the light receiving surface of the CCD 12 through an objective lens (not shown) and a color filter (not shown), whereby a subject image of the observation site is formed on the light receiving surface of the CCD 12. . In the present embodiment, a single-plate type is applied as an imaging method, and a primary color filter (not shown) including red (R), green (G), and blue (B) color elements is provided on the light receiving surface of the CCD. ) Is arranged. In the CCD 12, an image signal of a subject image corresponding to a color passing through the color filter is generated by photoelectric conversion, and image signals for one frame or one field are sequentially read at predetermined time intervals. Here, the NTSC system is applied as a color television system, and image signals for one frame (one field) are sequentially read out at intervals of 1/30 (1/60) second and transmitted to the initial signal processing circuit 19. Can be
[0023]
The initial signal processing circuit 19 performs an amplification process on the read image signal and converts the analog signal into a digital signal. Then, various processes such as gain control and gamma correction based on white balance adjustment are performed on the digital image signal to generate a luminance signal Y and color difference signals Cb and Cr. The luminance signal Y and the color difference signals Cb, Cb are sent to the circuit 28 of the processor 20. Further, the luminance signal Y is sent to the system control circuit 36 and the peripheral control circuit 35 of the processor 20 for light quantity adjustment.
[0024]
The luminance signal Y and the color difference signals Cb and Cr sent to the processor signal processing circuit 28 are converted into video signals such as NTSC signals and output to the monitor 52. Thereby, the subject image is displayed on the monitor 52 in real time.
[0025]
A system control circuit 36 including the CPU 26 controls the entire processor 20, controls image display on the monitor 52, and outputs control signals to various circuits such as the timing control circuit 42. The ROM 27 in the system control circuit 36 stores data relating to the characteristics of the lamp 24 and a program relating to control of the entire processor 20. In the timing control circuit 42, a clock pulse for adjusting the signal processing timing is output to each circuit in the processor 20, and a synchronization signal added to the video signal is sent to the processor signal processing circuit 28.
[0026]
The stop 22 provided between the entrance end 13a of the light guide 13 and the condenser lens opens and closes to adjust the amount of light irradiated to the subject, and when a control signal is sent from the system control circuit 36 to the peripheral control circuit 35. A drive signal is output to the stop 22 to drive the stop 22 by a predetermined amount. As a result, the amount of light applied to the subject is adjusted.
[0027]
The video scope 10 includes a scope control unit 15 for controlling the entire video scope 10 and an EEPROM 14 in which data relating to the characteristics of the video scope 10 and white balance adjustment are stored in advance. The scope control unit 15 sends a control signal to the initial signal processing circuit 19 and reads data from the EEPROM 14 as appropriate. While the video scope 10 is connected to the processor 20, data is mutually transmitted between the scope control unit 15 and the system control circuit 36, and data on scope characteristics and white balance adjustment is sent to the system control circuit 36 of the processor 20. At the same time, the data on the lamp characteristics of the processor 20 is sent to the scope control unit 15. The data transmitted from the video scope 10 is stored in the RAM 25 in the system control circuit 36, and the data transmitted from the processor 20 is stored in the EEPROM 14 in the video scope 10.
[0028]
The front panel 70 of the processor 20 is provided with a white balance adjustment switch 70A. When the white subject WW is arranged at the tip of the video scope 10 and the white balance adjustment switch 70A is operated, the white balance adjustment is performed. You. That is, in the initial signal processing circuit 19, the R and B gain values of the R, G and B signals are determined. After the white balance ends, a gain control process is performed on the image signal based on the set R and B gain values. Thus, a subject image with good color reproducibility is displayed on the monitor 52.
[0029]
When the keyboard 50 is operated, a signal corresponding to the operation is sent to the system control circuit 36, and a control signal is sent to a CRTC (CRT controller) 43 based on the signal. Then, a character signal corresponding to the key operation is sent from the CRTC 43 to the processor signal processing circuit 28, and is superimposed on the video signal. Thereby, the character information is displayed on the monitor 52 together with the subject image.
[0030]
FIG. 2 is a diagram showing a main routine of the processor 20. When the power of the processor 20 is turned on, a main routine is started.
[0031]
In step S101, parameters and the like are initialized. At this time, the value of the white balance data WB is set to 0. The white balance data WB is data for confirming whether or not the white balance adjustment has been performed. The white balance data WB is set to “1” when the white balance adjustment is performed, and is set to “0” when the white balance adjustment is not performed. Then, in step S102, various processes (normal processes) such as a process related to the keyboard 50 are performed. Step S102 is repeatedly performed until the power is turned off.
[0032]
FIG. 3 is a diagram showing an interrupt routine of a process related to the connection of the video scope 10, and FIG. 4 is a diagram showing a display screen of the monitor 52. This interrupt routine performs processing by interrupting the main routine at predetermined time intervals. An image control process related to white balance adjustment will be described with reference to FIGS.
[0033]
In step S201, it is determined whether or not the video scope 10 is connected to the processor 20. If it is determined that the video scope 10 is not connected, the process proceeds to step S210. In step S210, the white balance data WB is set to 0, and the interrupt routine ends. On the other hand, when it is determined in step S201 that the video scope 10 is connected, the process proceeds to step S202.
[0034]
In step S202, it is determined whether the white balance data WB is 0. That is, it is determined whether the white balance adjustment has not been performed yet. If it is determined that the white balance data WB is not 0, that is, it is determined that the white balance adjustment has already been performed, this routine ends as it is. On the other hand, if it is determined that the white balance data WB is 0, that is, it is determined that the white balance adjustment has not been performed, the process proceeds to step S203.
[0035]
In step 203, it is determined whether the previous lamp data and the scope data regarding the white balance adjustment have been read from the EEPROM 14. The previous lamp data is data stored in the EEPROM 14 when the video scope 10 has previously adjusted the white balance, and indicates the lamp characteristics at the time of the previous white balance adjustment, that is, the characteristics of the light source provided in the processor used last time. The data is stored in the EEPROM 14 as indicated data. If it is determined that the reading of the lamp data and the scope data has been completed last time, the interrupt routine ends as it is. On the other hand, when it is determined that the reading of the lamp data and the scope data has not been completed last time, the process proceeds to step S204.
[0036]
In step S204, the previous lamp data is read from the EEPROM 14 of the video scope 10 together with the scope data. Then, in step S205, it is determined whether the lamp data indicating the lamp characteristic according to the lamp 24 in the processor 20 matches the previous lamp data.
[0037]
When it is determined in step S205 that the lamp data is equal to the previous lamp data, that is, the lamp characteristics of the lamp 24 when the white balance is adjusted last time are equal to the lamp characteristics of the lamp 24, the process proceeds to step S206, and the white balance data setting process is executed. And the white balance data WB is set to “1”. That is, the R and B gain values stored in advance in the EEPROM 14 in association with the lamp data of the last use are set as they are. Then, in step S207, the subject image is displayed on the entire screen of the monitor 52 as a normal display (see FIG. 4). When step S207 is executed, the interrupt routine ends.
[0038]
On the other hand, if the lamp data is not equal to the previous lamp data in step S205, that is, if the lamp characteristics at the time of the previous white balance adjustment are different from the lamp characteristics of the lamp 24 of the processor 20, the process proceeds to step S208. In step S208, a control signal is output from the system control circuit 36 to the CRTC 43 in order to display on the monitor 52 character information that prompts the operator to perform the white balance adjustment. The CRTC 43 outputs a corresponding character signal. As a result, the character information “white balance required” is displayed on the monitor 52. Then, in step S209, a mask process is performed so that only a part of the subject image is displayed on the monitor 52 (see FIG. 4). That is, the CRTC 43 outputs a character signal corresponding to the mask display so that a part of the subject image is displayed in the region IR, and is superimposed on the video signal. When step S209 is executed, the interrupt routine ends.
[0039]
FIG. 5 is a diagram showing a white balance adjustment processing routine. When the operator operates the white balance adjustment execution switch 70A, the routine is started.
[0040]
In step S301, a command for starting execution of white balance adjustment is transmitted to the video scope 10. Then, in step S302, the lamp data of the processor 20 is transmitted to the video scope 10 and stored in the EEPROM 14. In the initial signal processing circuit 19, white balance adjustment processing is performed on an image signal obtained by photographing the white subject WW, and R and B gain values are determined. When the R and B gain values are determined, data notifying the end of the white balance adjustment is transmitted to the processor 20. Note that the transmitted lamp data is used as the previous lamp data at the next white balance adjustment. The R and B gain values determined by the white balance adjustment are stored in the EEPROM 14 in association with the transmitted lamp data.
[0041]
In step S303, it is detected whether data notifying the end of the white balance has been transmitted from the video scope 10. If it is determined that the data has been transmitted, the white balance data WB is set to 1 to end the white balance adjustment. Is done. Then, in step S304, a control signal is sent from the system control circuit 36 to the CRTC 43 to switch from the mask display to the normal display. Thus, the subject image is normally displayed on the entire screen of the monitor 52.
[0042]
As described above, according to the present embodiment, the lamp data indicating the characteristics of the lamp 24 is stored in the ROM 27 in the processor 20 and the lamp data of the processor used in the previous white balance adjustment is stored in the EEPROM 14 in the video scope 10. Is stored. Then, when the video scope 10 is connected to the processor 20, it is determined whether or not the lamp types match based on the lamp data indicating the characteristics of the lamp 24 and the lamp data transmitted from the video scope 10. (S205). If the types of the lamps 24 do not match, only a part of the subject image is displayed on the monitor 52 (S209), and the operator cannot proceed with the endoscope operation. When the white balance adjustment execution switch 70A is operated, the lamp data of the lamp 24 is transmitted to the video scope 10. Then, in the initial signal processing circuit 19, the R and B gain values of the R, G and B signals are adjusted based on the transmitted lamp data, and when the white balance adjustment is completed, the subject image is normally displayed. On the other hand, when the type of the light source is the same, the subject image is displayed as it is (S207).
[0043]
If the type of the light source is different as described above, an image is displayed so that the endoscope operation does not proceed, so that it is possible to prevent a treatment or the like while observing a subject image having poor color reproducibility. Further, when a lamp whose spectral distribution characteristic hardly changes regardless of the use time is continuously used, the subject image is displayed as it is without adjusting the white balance, and the working efficiency of the endoscope increases.
[0044]
In addition, it is not limited to the mask display shown in FIG. 4 and it can be confirmed that the image captured by the video scope 10 is displayed. However, the observation of the subject image (endoscopic work) is hindered, and the endoscope work is performed. What is necessary is just to display the video which cannot advance. Alternatively, the present invention is not limited to the image display, and a means for preventing the endoscope operation from proceeding (for example, sounding a loud buzzer or disabling the operation member of the video scope) may be applied.
[0045]
In the case of a metal halide lamp, the spectral distribution characteristics slightly change according to the use time. Therefore, a means for detecting the spectral distribution characteristic when the scope is connected may be provided so as to determine whether the spectral distribution characteristic is substantially the same as the previous spectral distribution characteristic. Alternatively, mask display may be performed so as to prompt white balance adjustment every time the scope is connected.
[0046]
In the present embodiment, the light source unit and the signal processing unit are integrally configured in the video processor 20, but the light source unit and the signal processing unit may be independently unitized.
[0047]
【The invention's effect】
As described above, according to the present invention, it is possible to prevent a subject image from being displayed based on white balance adjustment in which light source characteristics are not suitable.
[Brief description of the drawings]
FIG. 1 is a block diagram of an electronic endoscope apparatus according to the present embodiment.
FIG. 2 is a diagram showing a main routine of a processor.
FIG. 3 is a diagram illustrating an interrupt routine of a process related to connection of a video scope.
FIG. 4 is a diagram showing a display screen of a monitor.
FIG. 5 is a diagram showing a white balance adjustment processing routine.
[Explanation of symbols]
10 Video scope 12 CCD (imaging device)
14 EEPROM (scope memory)
19. Initial signal processing circuit (signal processing means)
20 Processor 24 Lamp (light source)

Claims (13)

An electronic endoscope apparatus including a video scope having an imaging element and a processor to which the video scope is connected,
A light source for illuminating the subject,
A signal processing unit that is provided in the video scope and executes a white balance adjustment process on an image signal corresponding to a subject image formed on the imaging element.
According to a spectral distribution characteristic of light emitted from the light source, light source determining means for determining the type of the light source,
When the type of the light source is different from the type of the previously used light source used at the time of the previous white balance adjustment, a work progress stop unit that does not advance the endoscope operation until the white balance adjustment is performed is provided. Electronic endoscope device. 2. The electronic device according to claim 1, wherein the work progress stopping means includes a video display control means capable of switching between a mask display indicating the necessity of white balance adjustment and a normal display for displaying the entire subject image. Endoscope device. The electronic endoscope apparatus according to claim 2, wherein the video display control unit displays only a part of the subject image on a screen. The electronic endoscope apparatus according to claim 2, wherein the video display control means displays character information so as to prompt the start of execution of white balance adjustment. Further comprising white balance completion determining means for determining whether the white balance adjustment has been completed,
3. The electronic endoscope apparatus according to claim 2, wherein the image display control unit normally displays a subject image when white balance is adjusted. 3. The electronic endoscope apparatus according to claim 2, wherein the image display control means normally displays a subject image when the type of the previously used light source is equal to the type. The processor has light source data transmission means for transmitting light source data according to the spectral distribution characteristics of the light source to the video scope,
The electronic endoscope apparatus according to claim 1, wherein the video scope has a scope memory capable of storing the light source data. 2. The electronic endoscope apparatus according to claim 1, wherein the light source determination unit determines whether or not the type of the light source at the time of the previous white balance adjustment matches when the video scope is connected. 3. A processor of an electronic endoscope apparatus connected to a video scope having an image sensor and capable of executing a white balance adjustment process,
A light source for illuminating the subject,
According to a spectral distribution characteristic of light emitted from the light source, light source determining means for determining the type of the light source,
When the type of the light source is different from the type of the previously used light source used at the time of the previous white balance adjustment, a work progress stop unit that does not advance the endoscope operation until the white balance adjustment is performed is provided. The processor of the electronic endoscope device. A videoscope for an electronic endoscope device connected to the processor according to claim 9,
An image sensor that generates an image signal according to a subject image;
A video scope for an electronic endoscope apparatus, comprising: signal processing means for executing white balance adjustment processing on an image signal corresponding to a subject image formed on the image sensor. A video display control device in an electronic endoscope apparatus including a video scope having an imaging device and capable of executing a white balance adjustment process and a processor to which the video scope is connected,
A spectral distribution characteristic detecting means for detecting a spectral distribution characteristic of light emitted from a light source for illuminating the subject,
When the detected spectral distribution characteristic is different from the spectral distribution characteristic at the time of the previous white balance adjustment, there is provided image display control means for executing a mask display indicating the necessity of the white balance adjustment until the white balance adjustment is performed. A video display control device for an endoscope, comprising: A video display control method in an electronic endoscope apparatus including a video scope having an imaging element and capable of executing a white balance adjustment process and a processor to which the video scope is connected,
Detecting the spectral distribution characteristics of light emitted from a light source for illuminating the subject,
When the detected spectral distribution characteristic is different from the spectral distribution characteristic at the time of the previous white balance adjustment, a mask display indicating the necessity of the white balance adjustment is performed until the white balance adjustment is performed. Video display control method. A program relating to image display control in an electronic endoscope apparatus including a video scope having an image sensor and capable of executing a white balance adjustment process and a processor to which the video scope is connected,
A spectral distribution characteristic detecting means for detecting a spectral distribution characteristic of light emitted from a light source for illuminating the subject,
When the detected spectral distribution characteristic is different from the spectral distribution characteristic at the time of the previous white balance adjustment, the image display control means for executing a mask display indicating the necessity of the white balance adjustment until the white balance adjustment is performed is functioned. Program characterized by the following.

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