JP2005169139A - Electronic endoscope apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic endoscope apparatus by which diagnosis under correct color reproduction using a securely white balance corrected endoscope is enabled. <P>SOLUTION: This electronic endoscope apparatus is equipped with a correction detecting means to detect the complement of color correction by a white balance correcting means, an attachment detecting means to detect whether the endoscope is attached/detached to/from a video processor, and a character generating means to generate character strings to be displayed on a monitor screen. Character strings are controlled corresponding to output signals from the correction detecting means and the attachment detecting means. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electronic endoscope that can accurately perform white balance correction.

  As is well known, an endoscope apparatus can observe a living body or the like that cannot be directly seen, and is widely used for observation and treatment mainly in the medical field. In recent years, electronic endoscope apparatuses that convert a subject image into an electrical signal using a solid-state imaging device such as a CCD and enable observation of a region to be inspected on a monitor screen have become widespread.

  This electronic endoscope apparatus has a higher resolution than a fiber-type (optical) endoscope, and is easy to record and reproduce an image. Also, an image can be enlarged, a comparison between two images, etc. It has advantages such as easy processing.

  The color imaging method of the electronic endoscope apparatus includes a surface sequential type in which illumination light is sequentially switched to red (R), green (G), blue (B), etc., and is irradiated on a region to be inspected; There is a simultaneous type in which a filter array in which color filters that transmit color lights such as R, G, and B are arranged in a mosaic pattern is arranged on the front surface of the image sensor. The frame sequential type has the advantage that the number of pixels can be reduced compared to the simultaneous type, while the simultaneous type has the advantage that no color shift occurs.

  It is well known that white balance must be adjusted in order to obtain good color image quality when color imaging is performed on a region to be inspected with this electronic endoscope apparatus.

  As the simplest method, there is known a method of correcting white balance of an electronic endoscope apparatus using a white paper or white gauze that is close to the user as an adjustment tool. In addition, there is a known method for correcting white balance by inserting the distal end portion of an endoscope into a white cylinder for white balance correction at the time of white balance correction of the electronic endoscope apparatus.

  However, when correcting the white balance of an electronic endoscope device, if the amount of light emitted from the lamp of the light source device is too bright or too dark, it is out of the dimming control range and is accurately corrected. There was a problem that could not be done.

  Also, due to the difference in the spectral characteristics of the color filter, which is arranged on the imaging surface of the CCD arranged at the distal end of the endoscope, or the difference in the light guide characteristics inserted through the endoscope, The color reproducibility of the subject image is different for each endoscope. For this reason, each time a different endoscope to be replaced is connected to the video processor, the white balance of the endoscope is corrected to correct individual differences.

  However, since there was no means for recognizing whether or not the endoscope connected to the video processor is white balance corrected, the inspection was performed with an endoscope that had not performed white balance correction. The accurate color reproducibility could not be obtained and the diagnosis could be adversely affected.

  The present invention has been made in view of the above circumstances, and makes it possible to easily recognize whether or not the endoscope connected to the video processor has already been subjected to white balance correction, thereby reliably performing white balance correction. It is an object of the present invention to provide an electronic endoscope apparatus that can perform diagnosis under accurate color reproducibility using an endoscope that has been performed.

  An electronic endoscope apparatus according to the present invention includes a white balance correction unit, a correction detection unit that detects completion of color correction by the white balance correction unit, and an attachment / detachment detection unit that detects attachment / detachment of the endoscope to / from a video processor. And a character generation circuit for generating a character string to be displayed on the monitor screen, and a character string generated from the character generation circuit according to output signals from the correction detection means and the attachment / detachment detection means. It is characterized by controlling.

  According to the present invention, it is possible to easily recognize whether or not an endoscope connected to a video processor has already been subjected to white balance correction, and use an endoscope that has been reliably subjected to white balance correction. Thus, it is possible to provide an electronic endoscope apparatus that can perform diagnosis under accurate color reproducibility.

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

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

  As shown in the figure, an electronic endoscope apparatus according to this embodiment includes an electronic endoscope (hereinafter also simply referred to as an endoscope) 1 having a built-in charge imaging element (hereinafter abbreviated as CCD) 2 as an imaging means. A video processor 3 as a signal processing device that performs signal processing on the CCD 2 of the endoscope 1, a light source device 4 as illumination light supply means for supplying illumination light to the endoscope 1, and the video processor 3 It is composed of a color monitor (not shown) that displays a video signal output after that. The endoscope 1 is detachably connected to the video processor 3 and the light source device 4.

  A lamp 13 and a diaphragm 14 for irradiating observation light are housed inside the light source device 4, and the value of the amount of light irradiated from the endoscope 1 can be controlled by the diaphragm 14. ing. The white light generated by the lamp 13 passes through the condenser lens 15a, is irradiated and supplied to the incident side end surface of the light guide 15, and extends to the distal end portion of the endoscope insertion portion 1a. The light is emitted from the illumination window 1b facing the surface toward the inspection site.

  On the other hand, the front panel 4a of the light source device 4 is provided with a light amount setting switch 16 which is an illumination light amount setting means for setting the irradiation light amount to a desired value. The value set by the light quantity setting switch 16 is input to the light source CPU 12 provided in the light source device 4 and stored as the value of the illumination light irradiation quantity at the time of observation. The light source CPU 12 outputs a predetermined voltage value based on the value of the illumination light quantity set by the light quantity setting switch 16, while comparing an output from a light control circuit 7 to be described later with this voltage value to reduce the aperture 14. Is controlled to an appropriate state.

  Further, when the white balance correction is performed for the light source CPU 12, the white balance correction is performed so that the irradiation light amount irradiated from the illumination window 1 b does not become too bright or too dark and becomes an optimal irradiation light amount. The amount of white balance correction light at that time is stored. The white balance correction light amount value is, for example, an intermediate value of a setting range that can be set by the light amount setting switch 16.

  The site to be inspected irradiated with the illumination light supplied from the light source device 4 forms an image on the imaging surface of the CCD 2 by an optical system attached to the observation window 1c adjacent to the illumination window 1b. The optical image of the region to be inspected imaged on the imaging surface of the CCD 2 is photoelectrically converted into an electrical signal by the CCD 2 and video is transmitted as a CCD output signal through a signal cable 2a inserted through the endoscope insertion portion 1a. It is transmitted to the processor 3. The CCD 2 is connected to a drive circuit (not shown) in the video processor 3 and the preamplifier 5 by a signal cable 2a inserted through the endoscope insertion portion 1a. The drive signal from the drive circuit is applied to the CCD 2 so that the photoelectrically converted signal is output from the CCD 2 as a CCD output signal.

  The CCD output signal output from the CCD 2 of the electronic endoscope 1 is amplified by a preamplifier 5 provided in the video processor 3 and output to a white balance correction circuit 6 and a light control circuit 7 which are white balance correction means. Is done. The electric signal input to the white balance correction circuit 6 and amplified by the preamplifier 5 is input to the signal processing circuit 8 through the white balance correction circuit 6, and is generated into a video signal by the signal processing circuit 8. It is output to a monitor (not shown).

  The front panel 3a of the processor 3 is provided with a white balance correction instruction switch (hereinafter abbreviated as a correction switch) 9 for outputting a white balance correction command. By pressing the correction switch 9, a white balance correction command is transmitted to the processor CPU 10.

  The correction switch 9 also serves as irradiation light amount switching means. When a white balance correction command is input to the processor CPU 10, the white balance correction circuit 10a, which is irradiation light amount switching means provided in the processor CPU 10, is provided. A command signal corresponding to the white balance correction command is output from the white balance correction circuit 6 and the light source CPU 12 provided in the light source device 4 via the connection cable 11 connected to the rear panel 3b. It has become.

  The operation of the electronic endoscope apparatus configured as described above will be described.

  The correction switch 9 is operated to correct the white balance. Then, the white balance correction command is transmitted to the processor CPU 10, and the value of the irradiation light amount set by the light amount setting switch 16 is forced from the white balance correction circuit 10 a of the processor CPU 10 to the light source CPU 12 in the light source device 4. In addition, a switching signal for switching to the light amount for white balance correction is output, and a command for correcting the white balance is output to the white balance correction circuit 6.

  In the light source CPU 12 that has received the switching signal for forcibly switching the value of the irradiation light amount from the white balance correction circuit 10 a to the white balance correction light amount, the emitted light amount is stored in the light source CPU 12. Is output to the aperture 14 to switch the irradiation light amount for white balance correction.

  On the other hand, the white balance correction circuit 6 of the video processor 3 expects that the dimming control is stabilized after the instruction signal is output from the light source CPU 12 (for example, the white balance correction light amount is obtained after a predetermined time elapses). After complete switching), correct the white balance.

  Then, after the white balance correction is completed, the light source CPU 12 sets the white balance correction light amount by the light amount setting switch 16 and stores it in the irradiation light amount value of the illumination light at the time of observation stored in the CPU 12. Switch.

  Thus, even when the value of the irradiation light amount set by the light amount setting switch is set to a value that is not appropriate for white balance correction at the time of white balance correction, it is provided in the video processor. The white balance correction is performed after receiving the white balance correction command from the white balance correction instruction switch, and forcibly switching the irradiation light quantity from the light source device to the white balance correction light quantity stored in the light source CPU. , You can always correct white balance.

  After the white balance correction is completed, the light amount of the illumination light output from the lamp by the light source CPU is changed from the white balance correction light amount to the illumination light irradiation light amount value at the time of observation set by the light amount setting switch. Since it can be switched, the troublesome operation of the light amount adjustment switch is eliminated.

  By the way, due to the difference in the spectral characteristics of the color filter disposed on the imaging surface of the CCD disposed at the distal end of the endoscope, or the difference in the light guide characteristics inserted into the endoscope, The color reproducibility of the subject image is different for each endoscope. For this reason, each time a different endoscope to be replaced is connected to the video processor, the white balance of the endoscope is corrected to correct individual differences.

  However, since there was no means for recognizing whether or not the endoscope connected to the video processor is white balance corrected, the inspection was performed with an endoscope that had not performed white balance correction. The accurate color reproducibility could not be obtained and the diagnosis could be adversely affected. For this reason, it is possible to easily recognize whether or not the endoscope connected to the video processor has already been subjected to white balance correction, and using an endoscope that has reliably performed white balance correction, There has been a demand for an electronic endoscope apparatus that can perform diagnosis based on accurate color reproducibility.

  2 and 3 relate to an embodiment of an electronic endoscope apparatus capable of recognizing whether or not white balance correction is performed, and FIG. 2 is a diagram showing another configuration of the electronic endoscope apparatus. FIG. 3 is a diagram illustrating a state in which a character string for notifying whether or not white balance correction has been performed is displayed on the monitor.

  As shown in FIG. 2, in the electronic endoscope apparatus of the present embodiment, a character string (such as “W / B failed”, “W / BO, K”, etc., is placed after the processor CPU 10 provided in the video processor 3. A character generating circuit 17 for generating a character signal is also provided. Then, the character signal generated from the character generation circuit 17 and the video signal output that is processed and output by the signal processing circuit 8 are superimposed and monitored as shown in FIGS. 3 (a) and 3 (b). A character string and an endoscopic image are displayed on the screen. Other configurations are the same as those of the above-described embodiment, and the same members are denoted by the same reference numerals and description thereof is omitted.

  The operation of the electronic endoscope apparatus configured as described above will be described.

  First, for example, the endoscope 1 is connected to the video processor 3. Then, connection detection contacts which are attachment / detachment detection means provided in the endoscope and the video processor are connected, and connection detection for notifying that the endoscope 1 is connected to the video processor 3 to the processor CPU 10 is detected. A signal is input. At this time, a signal notifying that the endoscope is connected to the character generation circuit 17 is output from the processor CPU 10. Upon receiving this signal, the character generation circuit 17 outputs a character string “W / B failed” instantaneously. Then, as shown in FIG. 3A, a character string “W / B failed” indicating that white balance correction is not performed is displayed on the monitor screen 81 of the monitor 80. Thus, the user can easily recognize that the white balance of the endoscope connected to the video processor 3 is not corrected by checking the monitor screen 81.

  Next, the correction switch 9 is operated to correct the white balance. Then, the white balance correction command is transmitted to the processor CPU 10, and the white balance correction command is output from the processor CPU 10 to the white balance correction circuit 6 and the character generation circuit 17. While white balance correction is performed, a detection signal notifying that the correction of white balance has been completed is output from the correction detection means provided in the white balance correction circuit 6 to the character generation circuit 17. In response to this detection signal, the character generation circuit 17 switches the output character string from “W / B failed” to “W / B O, K”. As a result, the character string “W / BO, K” indicating that the white balance has been corrected is displayed on the monitor screen 81 as shown in FIG. By doing so, it can be easily understood that the white balance of the endoscope connected to the video processor 3 has been corrected.

  In this way, when the endoscope is connected to the video processor, whether the white balance correction of the endoscope connected to the video processor is performed on the monitor screen is used. The character string to be recognized by the user is displayed, and after the white balance correction is performed by operating the correction switch, the character string indicating the white balance correction is switched and displayed on the monitor screen. The person can easily recognize whether or not the white balance correction of the endoscope connected to the video processor is corrected only by checking the monitor screen. This prevents white balance correction from being forgotten and ensures diagnosis based on accurate color reproducibility.

  Note that no character string is displayed on the monitor screen when the endoscope is detached from the video processor. Further, when a white balance correction command is output, the character signal output from the character generation circuit may be stopped so that the character string “W / B failed” is not displayed on the monitor screen. Furthermore, the character string displayed on the monitor screen is not limited to the above-mentioned “W / B failed” and “W / BO, K”, and the white balance has been corrected with an illustration instead of the character string. You may be made to notify a user whether it exists.

  By the way, the amount of irradiation light can be adjusted by operating the light amount setting switch provided on the front panel of the light source device. However, in the endoscope room where the surroundings are dark, the direction of the switch operation is changed. There was a case where the setting of the light quantity setting switch was mistaken. For this reason, there has been a demand for an electronic endoscope apparatus including a light source device that improves the operability by preventing erroneous operation of a light amount setting switch disposed on the front panel.

  FIG. 4 relates to an embodiment of an electronic endoscope apparatus in which an erroneous operation of a light amount setting switch of the light source apparatus is prevented. FIG. 4 (a) is a diagram showing another configuration of the electronic endoscope apparatus, and FIG. These are explanatory drawings which show the light quantity setting switch of the front panel.

  As shown in FIG. 4A, the light amount setting switch 16 is provided on the front panel 4a of the light source device 4, and the value of the irradiation light amount set by the light amount setting switch 16 is input to the light source CPU 12 and stored. It has come to be.

  As shown in FIG. 4B, the light quantity setting switch 16 is provided with an LED switch 19 in which an LED for display is arranged, and the setting quantity by the light quantity setting switch 16 is changed to cope with the setting quantity. The LED is turned on for the predetermined value.

  On the other hand, as shown in FIG. 4A, a buzzer 18 is connected to the light source CPU 12 inside the light source device 4, and different buzzer sounds are generated according to the increase / decrease of the set amount by the light amount setting switch 16. It is like that.

  The buzzer sound emitted from the buzzer 18 generates, for example, a continuous tone with a high pitch and a short generated sound interval as the light amount setting switch 16 is operated in a direction to increase the irradiation light amount, and in a direction to decrease the irradiation light amount. It is set to generate a continuous tone with a low pitch and a long interval between generated sounds as it is operated. Other configurations and operations are the same as those of the above-described embodiment, and the same members are denoted by the same reference numerals and description thereof is omitted.

  In this way, by connecting a buzzer to the light source CPU and generating a predetermined buzzer sound corresponding to the increase / decrease of the irradiation light amount by the switch operation of the light amount setting switch provided on the front panel of the light source device, the light amount setting is performed. The operation direction of the switch can be determined. As a result, even in the surrounding dark endoscope room or the like, the operation direction to be adjusted by the switch can be easily determined, and setting errors can be prevented.

  In the present embodiment, it is possible to recognize the increase / decrease of the irradiation light amount by the light amount setting switch provided on the front panel of the light source device by a buzzer sound. However, the present invention is not limited to the light amount setting switch. You may make it apply to the switch for color tone adjustment etc. which are provided in the front panel of a processor.

  By the way, when white balance correction is performed in an electronic endoscope device, white gauze is put on the endoscope tip, or the endoscope tip is placed in the inner hole of the white tube for white balance correction. The white balance was corrected by operating the switch. For this reason, an electronic endoscope apparatus that improves the workability of white balance correction has been desired.

  FIG. 5 is an explanatory diagram showing a schematic configuration of an electronic endoscope apparatus that improves the operability of the white balance correction work.

  As shown in the figure, the front panel 3a of the video processor 3 of the electronic endoscope apparatus of the present embodiment is provided with a white balance correcting cylinder portion (hereinafter abbreviated as a cylinder portion) 31 whose inner peripheral surface is colored white. ing. Photo switches 32 a and 32 b are arranged on the side peripheral surface of the cylindrical portion 31, and are formed by photo switches 32 a and 32 b by inserting the distal end portion of the endoscope into the cylindrical portion 31. By blocking the optical path, a white balance correction command is output to the processor CPU instead of the correction switch 9 of the above-described embodiment. In addition, when the inner peripheral surface of the cylinder part 31 is dirty, the cylinder part 31 is detachable from the front panel 3a so that it can be removed from the video processor and removed.

  In this way, a white balance correction cylinder portion having a white inner peripheral surface is provided on the front panel of the video processor, and a photo switch that also serves as a white balance correction instruction switch is provided on the white balance correction cylinder portion. White balance correction can be automatically performed simply by inserting the tip portion into the white balance correction cylinder. This eliminates the hassle of preparing white gauze, white balance correction white cylinders, etc., and can greatly improve the workability of white balance correction by eliminating the need to press the white balance correction switch. .

  Conventionally, when white balance correction is performed, KNEE processing is performed. For this reason, since white balance correction had to be performed by analog signal processing, it was necessary to perform circuit adjustment so that a predetermined input / output value was obtained after white balance correction.

  On the other hand, when white balance correction is performed by digital signal processing, the circuit is located after the A / D converter, so KNEE processing cannot be performed well, and white balance correction is performed as shown in FIG. Since it was difficult to perform processing so that the subsequent KNEE points match each color component, accurate color reproducibility could not be obtained as shown in FIG. Therefore, an electronic endoscope apparatus that performs white balance correction by digital signal processing to eliminate the need for circuit adjustment and that does not change the KNEE characteristics even when white balance correction is performed at a later stage of KNEE processing is desired. It was rare.

  As shown in FIG. 7, in this embodiment, the output signal of the CCD 2 is amplified by the preamplifier 5 and output to the KNEE processing circuit 20 and subjected to KNEE processing by the KNEE processing circuit 20, and then analogized by the A / D converter 21. Convert the signal to a digital signal. A digital multiplier 22 is connected after the A / D converter 21. For this reason, as the output signal from the CCD 2, a time-sequential frame sequential video signal corresponding to the plane sequential irradiation light irradiated through a rotating filter in the light source device (not shown) is output.

  The output of the A / D converter 21 is also input to the averaging circuit 23. The averaging circuit 23 calculates a white balance correction coefficient. The white balance correction coefficient is given to the digital multiplier 22 as a multiplication coefficient to perform white balance correction. The output from the multiplier 22 is input to a synchronization memory 24, converted into a synchronization signal, and then converted into an analog signal by a D / A converter 25 connected to each of R, G, and B signals. It is converted and output.

  The KNEE circuit is a non-linear circuit with one broken line that lowers the degree of amplification with respect to a predetermined level or higher of the input signal. The white balance correction coefficient is converted to an analog signal by the D / A converter 26 and input to the KNEE processing circuit 20.

  That is, as shown in FIG. 8A, according to the white balance correction coefficient, the KNEE processing KNEE point is set for each R, G, B component of the frame sequential video signal input to the KNEE processing circuit 20. Then, after white balance correction is performed as shown in FIG. 5B, processing is performed so that the KNEE points match in each color component. As a result, the color change in the high luminance region is eliminated, and accurate color reproducibility can be obtained.

  It should be noted that the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the invention.

[Appendix]
According to the embodiment of the present invention as described above in detail, the following configuration can be obtained.

(1) In an electronic endoscope apparatus having a white balance correction unit and an irradiation light amount setting unit capable of arbitrarily setting a value of the irradiation light amount, when the white balance correction unit is operated, it is set by the illumination light amount setting unit. An electronic endoscope apparatus having irradiation light amount switching means for switching a value of the irradiation light amount that has been set to a preset light amount value for white balance correction.

(2) white balance correction means;
Correction detection means for detecting the completion of color correction by the white balance correction means;
Attachment / detachment detection means for detecting attachment / detachment from the processor of the endoscope;
In an electronic endoscope apparatus having a character generation circuit for generating a character string to be displayed on a monitor screen,
In response to the output signals from the correction detection means and the attachment / detachment detection means, the electronic endoscope apparatus (3) for controlling the character string generated from the character generation circuit performs a knee process on the surface sequential video signal, In an electronic endoscope apparatus that performs white balance correction processing based on
An electronic endoscope that controls the knee processing in the knee processing circuit in correspondence with the correction coefficient of the white balance correction circuit.

The figure which shows the structure of the electronic endoscope apparatus which concerns on 1st Embodiment of this invention. 2 and 3 relate to an embodiment of an electronic endoscope apparatus capable of recognizing whether or not white balance correction is performed, and FIG. 2 is a diagram showing another configuration of the electronic endoscope apparatus. The figure which shows the state which displayed on the monitor the character string which announces whether it is the state in which white balance correction | amendment was performed Configuration of the electronic endoscope apparatus that prevents erroneous operation of the light quantity setting switch of the light source apparatus and an explanatory diagram of the light quantity setting switch provided on the front panel Explanatory drawing which shows schematic structure of the electronic endoscope apparatus which improves the operativity of white balance correction work. The figure which shows the KNEE point after the conventional white balance correction | amendment, and the color signal for each color The block diagram which shows the knee process in an electronic endoscope apparatus The figure which shows the KNEEE point after white balance correction | amendment, and the color signal for every color

Explanation of symbols

1 ... Electronic endoscope
3 ... Video processor
4. Light source device
6. White balance correction circuit (W / B)
9. White balance correction instruction switch (correction switch)
10a ... White balance correction circuit
16: Light quantity setting switch
Attorney Susumu Ito

Claims (1)

White balance correction means;
Correction detecting means for detecting completion of color correction by the white balance correcting means;
Attaching / detaching detecting means for detecting attachment / detachment of the endoscope with respect to the video processor;
A character generation circuit for generating a character string to be displayed on the monitor screen;
Comprising
An electronic endoscope apparatus, wherein a character string generated from the character generation circuit is controlled in accordance with output signals from the correction detection means and the attachment / detachment detection means.

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