JP2013116277A - Electronic endoscope, white balance adjustment method, electronic endoscope system, and white balance adjustment tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic endoscope capable of adjusting the white balance of two imaging devices at once, and to provide a white balance adjustment method, an electronic endoscope system and a white balance adjustment tool.SOLUTION: The electronic endoscope 10 includes: a first imaging part 12 provided on an insertion part distal end 11a; a second imaging part 13 provided on an insertion part side face 11b; and a memory for storing a difference between the gain value of video signals after white balance adjustment of the first imaging part 12 upon shipping and the gain value of video signals after white balance adjustment of the second imaging part 13, as a correction value for the white balance during observation. The white balance adjustment jig 50 includes: a bottom part 51 facing the first imaging part 12; and a wall part (projection part) 52a facing the second imaging part 13. During the observation, a difference between the gain value of the video signals after the white balance adjustment of the first imaging part 12 and the correction value stored in the memory is used as the gain value of the video signals of the second imaging part 13.

Description

  The present invention relates to an electronic endoscope scope, a white balance adjustment method, an electronic endoscope system, and a white balance adjustment jig.

  In an electronic endoscope for observing digestive organs such as the small intestine and large intestine, it is desirable to be able to observe 360 ° at a time in order to prevent oversight during observation and to shorten the observation time. In view of this, development of an electronic endoscope system in which a plurality of image sensors are provided in an electronic endoscope scope and which can be simultaneously observed by a plurality of image sensors has been advanced.

  In general, in an electronic endoscope system, a white jig performed on a video signal obtained from a subject is adjusted using a cylindrical jig that covers an image sensor so that a captured image becomes white. There have been proposed examples in which this white balance adjustment is performed in a compound eye camera having two imaging units (see Patent Documents 1 and 2).

JP 2009-130681 A JP-A 63-244011

  However, when the two image pickup units face the same optical axis direction and the distance from the image sensor is short, white balance can be executed using the above-described jig, but the distance between the two image sensors is long. In this case, since the two image sensors cannot be accommodated in the white balance adjustment jig, it is necessary to adjust the white balance for each image sensor. Further, a white balance adjustment jig for each image sensor is required.

  Therefore, an object of the present invention is to provide an electronic endoscope scope, a white balance adjustment method, an electronic endoscope, and a system white balance adjustment jig capable of white balance adjustment of a plurality of image sensors at a time.

  The present invention has been made to solve the above problems, and an electronic endoscope scope according to the present invention is provided on a first imaging element provided at a distal end of an insertion portion and on a side surface of the insertion portion. The second image sensor, the gain value of the video signal after the first white balance adjustment is performed on the video signal read from the first image sensor, and the second image sensor And a memory that stores a difference between the gain value of the video signal after the second white balance adjustment is performed on the video signal as a correction value for white balance at the time of observation.

  In this electronic endoscope scope, the white balance adjustment jig at the time of shipment and observation of each image sensor provided on the tip and side of the insertion portion is made into a white balance adjustment jig by the white balance adjustment jig according to the present invention. It is executed just by inserting it once.

  In this electronic endoscope scope, it is preferable that the second imaging element is provided in the bending portion of the insertion portion so that a wide range can be observed at a time.

  A white balance adjustment method according to the present invention is a white balance adjustment method for an electronic endoscope scope according to the present invention, in which a third white balance adjustment is performed on a video signal read from a first image sensor. The difference between the gain value of the video signal of the first image sensor after the third white balance adjustment and the correction value stored in the memory is used as the gain value of the video signal of the second image sensor at the time of observation. It is characterized by calculating.

  By this method, the white balance adjustment at the time of observation of the electronic endoscope scope according to the present invention is executed once.

  The electronic endoscope system according to the present invention is read from the first image sensor provided at the distal end of the insertion section, the second image sensor provided on the side surface of the insertion section, and the first image sensor. The second white balance adjustment was performed on the video signal gain value after the first white balance adjustment was performed on the video signal and the video signal read from the second image sensor. An electronic endoscope scope including a memory for storing a difference from a gain value of a subsequent video signal as a correction value for white balance at the time of observation, a bottom portion facing the first imaging element, and a second imaging And a white balance adjustment jig of an electronic endoscope scope including a wall portion facing the element.

  In this electronic endoscope system, white balance adjustment at the time of production and observation is executed once.

  A white balance adjusting jig according to the present invention is a white balance of an electronic endoscope scope that includes a first image sensor provided at a distal end of an insertion portion and a second image sensor provided on a side surface of the insertion portion. An adjustment jig, wherein the white balance adjustment jig includes a bottom portion facing the first image sensor and a wall portion facing the second image sensor.

  With this configuration, the white balance adjustment of each image sensor of the electronic endoscope scope according to the present invention is executed at a time.

  According to the present invention, it is possible to provide an electronic endoscope scope, a white balance adjustment method, an electronic endoscope system, and a white balance adjustment jig capable of adjusting a white balance of a plurality of image sensors at a time.

It is explanatory drawing which shows the structure and circuit structure of an electronic endoscope system provided with the electronic endoscope scope which concerns on embodiment of this invention. It is explanatory drawing explaining the state by which the electronic endoscope scope which concerns on embodiment of this invention was inserted in the white balance adjustment jig | tool. It is explanatory drawing explaining the curved part of an electronic endoscope scope. It is a perspective view which shows the white balance adjustment jig which concerns on embodiment of this invention. It is a flowchart of the white balance adjustment process at the time of shipment. It is a flowchart of the white balance adjustment process at the time of observation.

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

  FIG. 1 is a diagram schematically showing a configuration and a circuit configuration of an electronic endoscope system including an electronic endoscope scope 10 according to an embodiment of the present invention, and FIG. FIG. 3 is an explanatory view for explaining a state of being inserted into the balance adjustment jig 50, FIG. 3 is an explanatory view for explaining the bending portion 11 c of the electronic endoscope scope 10, and FIG. 4 shows the white balance adjustment jig 50. It is a typical perspective view.

  As shown in FIG. 1, the electronic endoscope system includes an electronic endoscope scope 10 used for photographing a subject, a processor 20 for processing a video signal sent from the electronic endoscope scope 10, and a subject image. And a white balance adjusting jig 50 shown in FIGS. The electronic endoscope scope 10 is detachably attached to the processor 20 and used. A monitor 40 is connected to the processor 20, and a side panel of the processor 20 is provided with a front panel FP for an operator to input an instruction signal and the like.

  The processor 20 receives a signal from the front panel FP, and is processed by a system controller 25 that controls the entire processor 20 and a pre-stage signal processing circuit 21 that processes a video signal sent from the electronic endoscope scope 10. An image memory 22 for storing the video signal, a post-stage video signal processing circuit 23 for performing processing for displaying a subject image or the like on the monitor 40, a timing controller 24, and a light source 29. In the timing controller 24, first and second drivers provided with clock pulses for adjusting the processing timing of signals are provided in each circuit in the processor 20 and a connector portion 18 (see FIG. 2) of the electronic endoscope scope 10 described later. It is output to the signal processing circuits 14 and 15.

  The light source 29 is supplied with power from a power source 26 controlled by the system controller 25. The amount of light emitted from the light source 29 is adjusted by a diaphragm 31 disposed in front of the condenser lens 30 via the condenser lens 30. The diaphragm 31 is opened and closed by driving the motor 28. Irradiation light consists of a bundle of ultra-fine optical fibers and enters the light guide L from the incident end Lc of the light guide L disposed in the electronic endoscope scope 10. The motor 28 is driven by a driver 27 that is controlled by a control signal from the front-stage signal processing circuit 21. As a result, the diaphragm 31 opens and closes by a predetermined amount.

  As shown in FIG. 2, the electronic endoscope scope 10 includes an operation unit 17 that is gripped by an operator and operates the movement of the electronic endoscope scope 10, and a connector unit that is detachably connected to the processor 20. 18 is provided. The operation portion 17 is connected to the proximal end of a flexible tubular insertion portion 11 to be inserted into the body of the subject. The insertion portion 11 is configured by sequentially connecting a flexible tube portion 11f, a bending portion 11c, and a distal end portion 11t. As for the bending part 11c of the insertion part 11, the bending part 11c curves up and down or the left-right direction by operation of the operation part 17 of an operator, for example, as shown in FIG. 3, the front-end | tip part 11t is orient | assigned to the desired direction.

  The light guide L reaches the insertion portion 11 through the operation portion 17 in the electronic endoscope scope 10, branches at the insertion portion 11, and extends to the insertion portion distal end 11a and the insertion portion side surface 11b, and has two end portions. It has La and Lb. The illumination light transmitted by the light guide L is irradiated from the end portions La and Lb toward the observation site via first and second light distribution lenses 12a and 13a described later.

  As shown in FIG. 3, in the insertion unit 11, the insertion unit distal end 11 a includes the first imaging unit 12, and the insertion unit side surface 11 b that is a side surface other than the insertion unit distal end 11 a includes the second imaging unit 13. The second imaging unit 13 is provided in the bending portion 11 c of the insertion unit 11. Due to the bending of the bending portion 11c, the second imaging unit 13 comes to face the insertion direction indicated by the arrow A (the insertion unit distal end 11a side), and the first imaging unit 12 is the direction opposite to the insertion direction (the operation unit 17 side). ). As described above, when the bending portion 11c is bent in a predetermined direction, it is possible to simultaneously observe both the front and rear in the insertion direction. When the bending portion 11c is used without being bent, the front side in the insertion direction by the first imaging unit 12 is slightly behind the observation site of the first imaging unit 12 by the second imaging unit 13. The region orthogonal to the observation region of the first imaging unit 12 is observed. As described above, the electronic endoscope scope 10 according to the embodiment of the present invention is configured to include the imaging units 12 and 13 having different imaging directions in the insertion unit 11 of one scope.

  As shown in FIG. 1, the first and second imaging units 12 and 13 are each guided by the light guide L and diffused to distribute the irradiation light emitted from the end portions La and Lb to the observation site. First and second light distribution lenses 12a and 13a, which are lenses, first and second objective lenses 12b and 13b that allow light reflected at the observation site to pass, and first and second imaging elements 12c and 13c With. As the first and second image sensors 12c and 13c, for example, CCDs or CMOS image sensors are used. In the present embodiment, since the front side in the insertion direction is mainly observed by the first image sensor 12c during normal observation, for example, the first image sensor 12c has 1.3 million pixels, and the second image sensor 13c has The number of pixels is set to about 300,000 pixels.

  The drive of the first image sensor 12c is controlled by a drive signal from the first driver signal processing circuit 14, and the drive of the second image sensor 13c is controlled by a drive signal from the second driver signal processing circuit 15. The first and second driver signal processing circuits 14 and 15 are controlled by the timing controller 24 of the processor 20. The light reflected at the observation site reaches the light receiving surfaces of the first and second imaging elements 12c and 13c via the first and second objective lenses 12b and 13b. As a result, a subject image of the observation site is formed on the light receiving surfaces of the first and second imaging elements 12c and 13c. Video signals generated by the first and second imaging elements 12c and 13c are sequentially read out according to a predetermined method and sent to the first and second driver signal processing circuits 14 and 15.

  In the first driver signal processing circuit 14, process processing such as first white balance adjustment is performed on the video signal read from the first image sensor 12 c after A / D conversion. In the second driver signal processing circuit 15, the video signal read from the second image sensor 13 c is subjected to process processing such as second white balance adjustment after A / D conversion. Each video signal subjected to the process processing is sent to the previous stage signal processing circuit 21 of the processor 20. As will be described later, the difference between the gain values of the video signal after white balance adjustment is stored in a memory 16 provided in the connector unit 18 (see FIG. 2) as a white balance correction value at the time of observation. Here, the white balance adjustment is an adjustment for adjusting the gains of R, G, and B so that the ratio of R: G: B is 1: 1: 1.

  As shown in FIGS. 2 and 4, the white balance adjustment is executed when the operator operates a switch provided on the front panel FP of the processor 20 using the white balance adjustment jig 50 shown in FIG. 4. .

  As shown in FIG. 4, the white balance adjusting jig 50 according to the embodiment of the present invention is configured such that when the insertion portion 11 of the electronic endoscope scope 10 is inserted in the direction of arrow A from the opening 52 b, the first The second imaging unit has a shape including a circular bottom 51 facing the imaging unit 12 and a cylindrical side surface 52 provided to be orthogonal to the bottom 51, and a part of the side surface 52 is cut away. The surface which opposes 13 comprises the protrusion part (wall part) 52a which protruded rather than the others. The inner side of the white balance adjustment jig 50 is painted white, and the inner surfaces of the bottom 51, the side surface 52, and the protrusion 52a are white regions that serve as a reference for white balance. The inner diameter of the side surface 52 is set to be slightly larger than the diameter of the insertion portion distal end 11 a of the electronic endoscope scope 10.

  The first imaging unit 12 of the electronic endoscope scope 10 inserted into the white balance adjustment jig 50 uses the inner surface of the bottom 51 of the white balance adjustment jig 50 and the second imaging unit 13. The white balance adjustment is executed using the inner surface of the protrusion 52a of the white balance adjustment jig 50. The white balance value is, for example, an R or B gain value. In this embodiment, in the white balance adjustment, the G signal is used as a reference so that the ratio of the R, G, and B signals obtained in the first and second driver signal processing circuits 14 and 15 is 1: 1: 1. The R and B gain values of the video signals obtained from the first and second image sensors 12c and 13c are adjusted.

  The gain value of the video signal after white balance adjustment is performed on the video signal read from the first image sensor 12c and the white balance for the video signal read from the second image sensor 13c. The difference from the gain value of the video signal after the adjustment is set at the time of production (at the time of factory shipment) as a correction value for white balance at the time of observation and is stored in the memory 16.

  At the time of observation, the white balance adjustment is executed by the first driver signal processing circuit 14 only for the video signal read from the first image sensor 12c using the white balance adjustment jig 50 described above. The difference between the gain value of the video signal of the first image sensor 12c obtained by the white balance adjustment and the correction value set during production is the gain value of the video signal of the second image sensor 13c at the time of observation. Is calculated as Using the calculated gain value, the second driver signal processing circuit 15 performs white balance adjustment on the video signal read from the second image sensor 13c.

  The digital video signals output from the first and second driver signal processing circuits 14 and 15 of the electronic endoscope scope 10 are subjected to predetermined signal processing in a preceding signal processing circuit 21 in the processor 20. The timings of the pre-stage signal processing circuit 21, the image memory 22, and the post-stage video signal processing circuit 23 are controlled based on a synchronization signal from the timing controller 24. Examples of the image processing performed by the pre-stage signal processing circuit 21 include contour enhancement, noise reduction, gamma correction, pseudo pigment dispersion processing, specific frequency enhancement, color conversion, and the like.

  In the post-stage video signal processing circuit 23, the image signal is converted into an analog signal, subjected to process processing such as amplification processing, clamping processing, blanking processing, and the like, and is output to, for example, the monitor 40 via a video signal cable (not shown). Is done. As a result, an image of the observation site is displayed on the monitor 40. In addition to the monitor 40, it may be connected to a device such as a video printer or a VCR. In addition, the processing timing in the post-stage video signal processing circuit 23 is controlled based on the synchronization signal from the timing controller 24.

  When a freeze button (not shown) of the operation unit 17 of the electronic endoscope scope 10 is operated, the image data in the image memory 22 is held, and the post-stage video signal processing circuit 23 holds the image data. Image data is output repeatedly. As a result, the image held in the image memory 22 is displayed on the monitor 40 as a still image. When the electronic endoscope scope 10 outputs an analog image signal, the preceding signal processing circuit 21 performs decoding processing and A / D conversion processing, and the same processing is performed thereafter.

  Next, a white balance adjustment method for the electronic endoscope scope 10 according to the present embodiment will be described with reference to FIGS. FIG. 5 is a flowchart of white balance adjustment processing at the time of shipment, and FIG. 6 is a flowchart of white balance adjustment processing at the time of observation.

  First, the white balance adjustment process at the time of shipment will be described with reference to FIG. The connector portion 18 of the electronic endoscope scope 10 is connected to the processor 20, for example, a predetermined switch operation is performed on the front panel FP, and the insertion portion 11 of the electronic endoscope scope 10 is moved from the opening 52b to the white balance adjusting jig. When it is inserted in 50, white balance adjustment processing is started. Prior to the white balance adjustment process, the electronic endoscope system is already turned on, the light source 29 is turned on, and control of the processor 20 and the electronic endoscope scope 10 is started. .

  In step S101, the video signal read from the first image sensor 12c uses the inner surface of the bottom 51 of the white balance adjustment jig 50, and the ratio of R, G, and B signals is 1: 1: 1. The R and B gain values are adjusted with the G signal as a reference, and R and B adjustment gain data R1 and B1 are obtained. In step S102, the video signal read from the second image sensor 13c uses the inner surface of the protrusion 52a of the white balance adjustment jig 50, and the ratio of R, G, and B signals is 1: 1: 1. R and B gain values are adjusted using the G signal as a reference so that R and B adjustment gain data R2 and B2 are obtained. In step S103, correction values Rd and Bd are obtained by calculating differences between R and B adjustment gain data R1 and B1 and R and B adjustment gain data R2 and B2. In step S104, the obtained correction values Rd and Bd are stored in the memory 16 as correction values for white balance at the time of observation, whereby the white balance adjustment process is completed.

  Next, white balance adjustment processing during observation will be described with reference to FIG. The connector portion 18 of the electronic endoscope scope 10 is connected to the processor 20, for example, a predetermined switch operation is performed on the front panel FP, and the insertion portion 11 of the electronic endoscope scope 10 is moved from the opening 52b to the white balance adjusting jig. When it is inserted in 50, white balance adjustment processing is started. Prior to the white balance adjustment process, the electronic endoscope system is already turned on, the light source 29 is turned on, and control of the processor 20 and the electronic endoscope scope 10 is started. .

  In step S201, the video signal read from the first image sensor 12c uses the inner surface of the bottom 51 of the white balance adjustment jig 50, and the ratio of R, G, and B signals is 1: 1: 1. Thus, the R and B gain values are adjusted with the G signal as a reference, and R and B adjustment gain data Rn1 and Bn1 are obtained. In step S202, the correction values Rd and Bd stored in the memory 16 are read, and the difference between the R and B adjustment gain data Rn1 and Bn1 and the correction values Rd and Bd is calculated. The values obtained by the calculation are used as R and B adjustment gain data Rn2 and Bn2 of the second image sensor 13 at the time of observation.

  In addition, when the white balance adjustment process at the time of observation is completed, a normal photographing operation of the electronic endoscope scope 10 is started. In a normal photographing operation, signal processing is performed based on the R and B adjustment gain data Rn1 and Bn1 and the R and B adjustment gain data Rn2 and Bn2 set by the white balance adjustment process at the time of observation.

  As described above, in the electronic endoscope scope, the white balance adjustment method, the electronic endoscope system, and the white balance adjustment jig according to the embodiment of the present invention, imaging with different shooting directions is performed on the insertion portion of one scope. In the electronic endoscope scope having the configuration, the two image pickup elements fit into the inner surface of one white balance adjusting jig at a time. For this reason, at the time of shipment, the white balance can be easily adjusted at a time without adjusting the white balance separately for each image sensor and without using two jigs.

  Further, the correction value is stored in the memory at the time of shipment, and the correction value is read from the memory at the time of observation, so that the white balance adjustment is performed only on the first image pickup element at the distal end of the scope insertion unit, and the second image pickup is performed. It is not necessary to adjust the white balance of the element. This facilitates white balance adjustment during observation. In addition, an existing white balance adjustment jig different from that at the time of shipment, for example, a cylindrical jig that does not partially protrude like the white balance adjustment jig according to the embodiment of the present invention, and the first imaging It is also possible to use a jig having a shape in which only the element is covered.

  In addition, the white balance adjustment jig according to the embodiment of the present invention has a shape having a protruding portion with a part of the side surface cut away, and the opposing surface of the second image sensor is cylindrical. is not. Since the white inner surface of the white balance adjustment jig may be reflected if the shape covers the entire side surface of the insertion portion where the second image sensor exists, the white balance adjustment jig facing the second image sensor It is preferable that the protrusion part of is partial.

  In the electronic endoscope scope and the white balance adjustment method according to the embodiment of the present invention, the correction value is the difference between the gain values of the two video signals, but the correction value is the ratio of the gain values of the two video signals. It doesn't matter.

DESCRIPTION OF SYMBOLS 10 Electronic endoscope scope 11 Insertion part 11a Insertion part front-end | tip 11b Insertion part side surface 12 1st image pick-up part 12c 1st image pick-up element 13 2nd image pick-up part 13c 2nd image pick-up element 16 Memory 20 Processor 21 Previous stage signal processing circuit 22 Image memory 23 Rear stage video signal processing circuit 24 Timing controller 25 System controller 40 Monitor 50 White balance adjustment jig 51 Bottom 52 Side 52a Projection (wall)
L Light guide A Insertion direction

Claims (5)

A first imaging element provided at the distal end of the insertion portion;
A second imaging element provided on a side surface of the insertion portion;
The gain value of the video signal after the first white balance adjustment is performed on the video signal read from the first image sensor and the video signal read from the second image sensor And a memory for storing a difference from the gain value of the video signal after the second white balance adjustment as a correction value for white balance at the time of observation.   The electronic endoscope scope according to claim 1, wherein the second imaging element is provided in a bending portion of the insertion portion. A white balance adjustment method for an electronic endoscope scope according to claim 1,
Performing a third white balance adjustment on the video signal read from the first image sensor;
The difference between the gain value of the video signal of the first image sensor after the third white balance adjustment and the correction value stored in the memory is the difference of the video signal of the second image sensor at the time of observation. A white balance adjustment method characterized by calculating as a gain value. A first imaging element provided at the distal end of the insertion portion;
A second imaging element provided on a side surface of the insertion portion;
The gain value of the video signal after the first white balance adjustment is performed on the video signal read from the first image sensor and the video signal read from the second image sensor An electronic endoscope scope including a memory that stores a difference between the gain value of the video signal after the second white balance adjustment and a correction value for white balance at the time of observation;
An electronic endoscope comprising: a white balance adjusting jig of the electronic endoscope scope, comprising: a bottom portion facing the first image sensor; and a wall portion facing the second image sensor. system. A white balance adjustment jig for an electronic endoscope scope comprising a first image sensor provided at a distal end of an insertion portion and a second image sensor provided on a side surface of the insertion portion,
The white balance adjusting jig includes a bottom portion facing the first image sensor,
A white balance adjustment jig, comprising: a wall portion facing the second imaging element.

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