JP2005111110A - Endoscope system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simplify processing for changing the visual field position of a magnified image and to rapidly perform the processing, in an endoscope system for displaying a wide-angle image and the magnified image. <P>SOLUTION: Fluorescent paint is applied on the tip end 41 of forceps 40, so as to make a position detection mark 42. The fluorescent paint for emitting light with a prescribed wave length is used, which is excited by the light with a specified wave length included in illumination light which is supplied from a light source device and is radiated from the tip end of a hard endoscope. The image signal of the wide angle image is acquired by the intervention of a color filter for transmitting only light with a wave length around the prescribed wave length. The component of the prescribed wave length is extracted from the image signal, so as to generate a luminance distribution. A high luminance area is detected from the luminance distribution. Then a shift optical system for changing the visual field position of the magnified image is driven so that the area is at the center of the magnified image. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an endoscope system for performing treatment by inserting a treatment instrument such as a rigid endoscope and forceps into a body cavity of a patient, and particularly relates to detection of the treatment tool.

  Conventionally, treatment using an endoscope (rigid endoscope) and forceps may be performed at a medical site. The rigid endoscope and the forceps are each inserted into a patient's body cavity through a trocar. A light guide is inserted through the rigid endoscope, and illumination light is irradiated forward from the tip of the rigid endoscope. An objective optical system is provided at the tip of the rigid mirror, and an object image is formed. A light beam from the objective optical system is branched and guided to a wide-angle photographing means for photographing a wide-angle image and an enlarged photographing means for photographing an enlarged image through a predetermined optical element. A wide-angle image and an enlarged image captured by each imaging unit are displayed on a display unit such as a TV monitor.

The distal end portion of the forceps is displayed on the enlarged image TV monitor. The practitioner performs a procedure such as excision of a lesion site with forceps while visually recognizing a wide-angle image and an enlarged image image of the TV monitor. Therefore, when the position of the forceps changes during the treatment, a process for converting the visual field position of the enlarged image is performed accordingly (for example, Patent Document 1).
Japanese Patent Laid-Open No. 08-332169

  In converting the position of the field of view of such an enlarged image, the position of the forceps is detected. The position detection of the forceps is based on the shape and color of the forceps known in advance and the image signal of each pixel constituting the wide-angle image is analyzed to detect the arrangement of the pixels constituting the area having the shape and color corresponding to the forceps Is done. Accordingly, there is a problem that the arithmetic processing is extremely complicated and the speed of visual field conversion is impaired. There is also a problem that the circuit scale for image processing increases.

  SUMMARY OF THE INVENTION An object of the present invention is to easily and quickly convert a visual field position of an enlarged image with respect to a change in the position of a forceps in an endoscope system that performs a procedure while visually recognizing the position of the forceps on a TV monitor. .

  An endoscope system according to the present invention includes a first photographing unit for photographing a wide-angle image formed by an objective optical system, and a second photographing for photographing an enlarged image of a partial region of the wide-angle image. Means, a wide-angle image display means for displaying a wide-angle image captured by the first imaging means, an enlarged image display means for displaying an enlarged image captured by the second imaging means, and a treatment instrument. A tracking control means for changing the field of view of the enlarged image so as to be included in the enlarged image, and the treatment tool is a high-intensity part in which a luminance value for a color of a predetermined wavelength is imaged higher than other regions in the wide-angle image The tracking control means includes position detection means for detecting a region having a higher luminance than other regions for the color of a predetermined wavelength in the wide-angle image as the position of the treatment tool, and the tracking control means detects the treatment tool detected by the position detection means. Based on position , And changes the view position of the enlarged image.

  According to the present invention, a portion having a relatively high luminance with respect to a color having a predetermined wavelength is formed on the treatment instrument, and the position of the treatment instrument is specified by detecting the high luminance portion in the wide-angle image. That is, since the position of the treatment tool is detected only by processing the luminance information, the processing is simplified, and the visual field change of the enlarged image is speeded up. Further, the circuit configuration for position detection can be reduced in size, which is economical.

  The high-luminance portion is formed, for example, by providing a fluorescent material that emits light of a predetermined wavelength when excited by light of a specific wavelength included in illumination light irradiated for photographing. Preferably, the endoscope system includes a filter that transmits light in the vicinity of the wavelength of the light emitted from the fluorescent material, and the filter is interposed on the optical path of the light beam guided from the objective optical system, or from the optical path. And a filter driving means for retracting. The tracking control means controls the filter driving means, interposes the filter on the optical path from the objective optical system, and captures a wide-angle image formed in that state by the first photographing means. Based on the signal, the processing of the position detecting means is executed.

  The high-luminance portion is formed by, for example, applying a color paint having a predetermined wavelength. Preferably, the first photographing unit is a solid-state imaging device having a color chip filter, the color of a predetermined wavelength is one color of the color chip filter, and the position detection unit is a color of a predetermined wavelength. A signal obtained from the pixel corresponding to the color chip filter is extracted.

  The high-luminance part is formed by, for example, providing a phosphorescent substance that accumulates light energy during external light irradiation and emits light based on the stored light energy when external light irradiation is stopped. Is done. Preferably, the tracking control unit executes the processing of the position detection unit in a state where irradiation of illumination light for photographing is stopped.

  Preferably, an operation member for instructing start and stop of processing of the tracking control means may be provided.

  The treatment instrument may have a plurality of the high-luminance portions described above, and preferably, the geometric shape formed by the plurality of high-luminance portions may be held in the storage unit. If a plurality of high-luminance portions are provided, the accuracy of detecting the position of the treatment tool can be further increased.

  As described above, according to the present invention, in an endoscope system that performs a procedure using a forceps while visually recognizing a wide-angle image and an enlarged image on a TV monitor or the like, the process of converting the visual field position of the enlarged image is simplified. The effect of being performed quickly is obtained.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram schematically showing an entire endoscope system to which an embodiment according to the present invention is applied. The rigid endoscope 10 is inserted into the patient's body through a trocar (not shown) or the like fitted into the patient's abdominal wall. An objective optical system 11 is disposed at the distal end of the rigid endoscope 10. The objective optical system 11 is a retrofocus type optical system capable of forming a wide range of field images. A relay optical system 12 is disposed in the rigid endoscope 10 along the longitudinal direction. As will be described later, the color filter 13 is a filter that transmits only light in the vicinity of a predetermined wavelength. The color filter 13 is positioned at a position (intervening position) interposed on the optical path of the light beam guided from the relay optical system 12 by a predetermined driving device (not shown), or a position retracted from the optical path (retracted position). Is positioned.

  The rigid endoscope 10 is connected to the image separation device 20. The observed object image formed by the objective optical system 11 is guided to the branch optical system 21 in the image separation device 20 via the relay optical system 12 or via the relay optical system 12 and the color filter 13. The branching optical system 21 is disposed on the optical path of the light beam from the objective optical system, reflects a part of the light beam, and transmits the rest.

  The light beam reflected by the branching optical system 21 is guided to the wide-angle CCD camera 23 through the wide-angle optical system 22 and is incident on an imaging region of an imaging device (not shown) provided in the wide-angle CCD camera 23.

  The light beam that has passed through the branching optical system 21 is reflected by the reflecting prism 24 and enters the magnifying optical system 25. The magnifying optical system 25 includes a shift optical system 26, a focusing lens 27, and a zooming lens group 28. The shift optical system 26 is composed of, for example, a Pechan prism, and is held so as to be movable in a direction perpendicular to the optical axis OA1 of the light beam from the reflecting prism 24. By appropriately moving the shift optical system 26, the optical axis OA2 of the light beam incident on the focusing lens 27 can be displaced with respect to the optical axis OA1.

  The light beam emitted from the magnifying optical system 25 is guided to the magnifying CCD camera 29 and enters the imaging region of an imaging device (not shown) provided in the magnifying CCD camera 29 perpendicularly. Accordingly, by driving the shift optical system 26, the position of the enlarged image in the wide-angle image is changed. Further, by appropriately driving the zooming lens group 28, the observed object image is magnified at a predetermined magnification.

  The wide-angle CCD camera 23 and the enlargement CCD camera 29 are connected to external monitors 31 and 32 by video cables, respectively. As a result, a wide-angle image of the object to be observed is displayed on the external monitor 31, and an enlarged image of a partial region of the wide-angle image is displayed on the external monitor 32.

  The light source device 50 supplies illumination light that irradiates the object to be observed. The light emitted from the light source device is guided to the distal end portion of the rigid endoscope 10 by a light guide (not shown) that passes through the interior of the rigid endoscope 10.

  The forceps 40 is inserted into the patient's body via a trocar (not shown) separate from the trocar of the rigid endoscope 10. The practitioner performs the treatment with the forceps 40 while visually checking the external monitors 31 and 32.

  FIG. 2 is a diagram schematically showing the vicinity of the distal end portion of the forceps 40 in an enlarged manner. A position detection mark 42 is formed by applying a fluorescent paint on the distal end portion 41 where the lesion site is excised. The fluorescent paint for the position detection mark 42 is a fluorescent paint that is excited by light of a specific wavelength included in illumination light supplied from the light source device 50 and irradiated from the tip of the rigid endoscope 10 and emits light of a predetermined wavelength. Used. Therefore, in the wide-angle image acquired by the wide-angle CCD camera 23 in the state where the illumination light is irradiated, the area corresponding to the position detection mark 42 has image information with higher brightness than the other areas. The color filter 13 is a filter that transmits only light in the vicinity of the wavelength of light emitted from the fluorescent paint.

  FIG. 3 is a block diagram of the endoscope system according to the first embodiment. The system controller 100 is a microcomputer that controls the entire endoscope system. The wide-angle image signal output from the wide-angle CCD camera 23 is subjected to predetermined image processing in the wide-angle image processing circuit 101 and is output to the external monitor 31. The image signal of the enlarged image output from the enlargement CCD camera 29 is subjected to predetermined image processing in the enlarged image processing circuit 102 and is output to the external monitor 32.

  A tracking control switch 103 is connected to the system controller 100. The tracking control switch 103 is turned on / off in conjunction with an operation of a tracking control button (not shown) provided in the image separation device 20 for changing the field position of the enlarged image. The system controller 100 is connected with an enlargement ratio designation dial 104. In response to the operation of the enlargement factor designation dial 104, a control signal indicating the enlargement factor of the enlarged image is input to the system controller 100.

  When the tracking control switch 103 is turned on in response to the operation of the tracking control button, a visual field position change control signal is input to the controller 100. When the control signal for changing the visual field position is input, a control signal for driving the color filter 13 (see FIG. 1) from the retracted position to the intervening position is output to the filter driving circuit 108. Based on this control signal, a drive signal is output from the filter drive circuit 108 to the filter drive device 109, and the color filter 13 is positioned at the intervening position.

  When a control signal for changing the visual field position is input, an image signal subjected to predetermined image processing by the wide-angle image processing circuit 101 is input to the tracking control circuit 106 based on the control of the system controller 100. That is, the tracking control circuit 106 receives an image signal that has been subjected to predetermined processing based on the light beam that has passed through the color filter 13.

  The tracking control circuit 106 detects a region (high luminance region) composed of pixels having relatively higher luminance than other regions. Further, the driving direction and the driving amount of the X direction driving motor 261 and the Y direction driving motor 262 are calculated so as to change the visual field position of the enlarged image so that the center of the enlarged image becomes a high luminance region.

  When drive signals are output from the tracking control circuit 106 to the X-direction and Y-direction drive motors 261 and 262, the shift optical system 26 (see FIG. 1) causes the optical axis OA1 of the light beam from the reflecting prism 24 (see FIG. 1). Are driven along the X and Y directions perpendicular to each other in a plane perpendicular to. On the other hand, the driving direction and the driving amount in which the X direction driving motor 261 and the Y direction driving motor 262 are actually driven are detected by the X direction encoder 263 and the Y direction encoder 264, respectively, and input to the tracking control circuit 106. The tracking control circuit 106 performs drive control of each motor so that the drive amounts of the X-direction and Y-direction drive motors 261 and 262 become the calculated drive amounts based on inputs from these encoders.

  The focusing lens 27 (see FIG. 1) is driven along the optical axis OA1 by the focusing motor 271. The driving direction and driving amount in which the focusing motor 271 is actually driven are detected by the focusing encoder 272 and input to the system controller 100. In the system controller 100, drive control of the focusing motor 271 is performed so that the driving amount of the focusing motor 271 becomes the calculated driving amount based on this input.

  The zooming lens group 28 is held by a cam ring (not shown). The cam ring is driven by a cam ring drive motor 281. When a control signal for changing the enlargement ratio is input from the enlargement ratio designation dial 104 to the system controller 100, the system controller 100 outputs a drive signal to the cam ring drive motor 281 based on this control signal. As a result, the cam ring is driven, the zooming lens group 28 is displaced along the optical axis OA1, and an enlarged image corresponding to the enlargement ratio is formed. The driving direction and driving amount in which the cam ring drive motor 281 is actually driven are detected by the cam ring encoder 282 and input to the system controller 100. In the system controller 100, drive control of the cam ring drive motor 281 is performed so that the drive amount of the cam ring drive motor 281 becomes the calculated drive amount based on this input.

  FIG. 4 is a flowchart illustrating a processing procedure of the visual field position changing process according to the first embodiment. When the tracking control switch 103 is turned on, the visual field position changing process is started. First, in step S100, the color filter 13 is driven to the above-described intervening position. Next, in step S102, an image signal of a wide-angle image that has been subjected to photoelectric conversion by the wide-angle CCD camera 23 and subjected to predetermined image processing in the wide-angle image processing circuit 101 is input to the tracking control circuit 106.

  In step S104, the same wavelength component as the wavelength of the light excited by the illumination light and emitted from the fluorescent paint of the position detection mark 42 is extracted from the image signal. Next, in step S106, the luminance distribution measurement process of the extracted image signal is performed. The luminance distribution measurement process is performed for each scanning line constituting the wide-angle image. For example, as shown in FIG. 5, when the center of the position detection mark 42 of the forceps 40 is on the scanning line m in the wide-angle image M1, the processing result of step S104 for the scanning line m is the brightness of the graph shown in FIG. Distribution.

  In step S108, the position detection process of the forceps 40 in the wide-angle image is performed. The position of the forceps 40 is determined based on the position of the position detection mark 42. That is, the vertical direction is determined from the position of the scanning line m in the wide-angle image, and the horizontal direction is determined from the position having the highest luminance in the scanning line m (Xp in FIG. 6).

  Next, the process proceeds to step S110, and the tracking control process of the forceps 40 is performed. The driving of the X-direction drive motor 261 and the Y-direction drive motor 262 is controlled so that the position detection mark 42 is positioned at the center of the enlarged image, and the visual field position of the enlarged image is changed.

  In step S112, whether the tracking control switch 103 is on or off is checked. If it is confirmed that the tracking control switch 103 remains on, the process returns to step S102, and the subsequent processing is repeated. When it is confirmed that the tracking control button is operated and the tracking control switch 103 is turned off, the process proceeds to step S114. After the process for driving the color filter 13 to the retracted position is performed in step S114, this routine ends.

  In the first embodiment, the position detection mark 42 may be formed by applying paint of the same color as one of the color chip filters provided on the image sensor of the wide-angle CCD camera 23 to the tip 41. Good. In this case, after the process of extracting only the image signal from the pixel corresponding to the color chip filter of the color of the position detection mark 42 is performed in step S104, the process of creating the luminance distribution is performed in step S106.

  Next, an endoscope system to which the second embodiment according to the present invention is applied will be described. In the second embodiment, the position detection mark 42 of the forceps 40 is formed by applying a phosphorescent substance. The phosphorescent substance is a substance that accumulates light energy while external light is irradiated, and emits light based on the accumulated light energy when the external light irradiation is stopped. In the second embodiment, unlike the first embodiment, the color filter 13 and its driving member are not provided.

  FIG. 7 is a block diagram of an endoscope system according to the second embodiment. When the tracking control switch 103 is turned on, the system controller 100 outputs a control signal for stopping the light source device 50 to the light source driving circuit 107. When the tracking control switch 103 is turned off, the system controller 100 outputs a control signal for driving the light source device 50 to the light source driving circuit. The light source driving circuit 107 drives and stops the light source device 50 based on a control signal from the system controller 100. That is, when the tracking control switch 103 is on, the supply of illumination light from the light source device 50 is stopped, and when it is off, illumination light is supplied from the light source device 50. Other configurations are the same as those of the first embodiment.

FIG. 8 is a flowchart illustrating the processing procedure of the visual field position changing process according to the second embodiment.
When the tracking control switch 103 is turned on, the visual field position changing process is started. First, in step S200, the supply of illumination light is stopped in the manner described above. In step S202, the wide-angle image that is not irradiated with illumination light is photoelectrically converted by the wide-angle CCD camera 23 and subjected to predetermined image processing in the wide-angle image processing circuit 101. The image signal subjected to the image processing is input to the tracking control circuit 106.

  In step S204, luminance distribution measurement processing is performed. The luminance distribution measurement process is performed for each scanning line constituting the wide-angle image. In step S200, irradiation of illumination light is stopped. Therefore, as shown in FIG. 9, in the wide-angle image M2, the brightness level of the area other than the position detection mark 42 provided at the distal end portion 41 of the forceps 40 is zero, and the brightness level of the area corresponding to the position detection mark 42 is High brightness. Therefore, when the center of the position detection mark 42 is on the scanning line m, the processing result of step S204 for the scanning line m is the luminance distribution of the graph shown in FIG.

  Next, in step S206, the position detection process of the forceps 40 in the wide-angle image is performed, and the process proceeds to step S208 where the tracking control process of the forceps 40 is performed. These processes are performed in the same manner as steps S108 and S110 in FIG.

  In step S210, ON / OFF of the tracking control switch 103 is checked. If it is confirmed that the tracking control switch 103 remains on, the process returns to step S202, and the subsequent processing is repeated. If it is confirmed that the tracking control button is operated and the tracking control switch 103 is turned off, the process proceeds to step S212. In step S212, the supply of illumination light is resumed, and this routine ends.

  In the first and second embodiments, the position detection mark provided on the forceps 40 is one, but is not limited thereto. For example, as shown in FIG. 11, three position detection marks 51, 52, and 53 may be provided. In this case, the geometric shape formed by the position detection marks 51, 52 and 53 (the dimension between the marks and the angle formed by the straight line connecting the marks) is held in a predetermined storage unit in advance. If the geometric shape is grasped in this way, the posture of the forceps 40 can be detected by comparing with the geometric shape formed by the three high-luminance regions in the wide-angle image. Even if a high-luminance region exists other than the position detection mark, the position of the forceps 40 can be accurately detected.

1 is a diagram schematically showing an overall view of an endoscope system to which a first embodiment according to the present invention is applied. It is an enlarged view of the front-end | tip part of forceps. It is a block diagram of the endoscope system of a 1st embodiment. It is a flowchart which shows the process sequence of the visual field position change in 1st Embodiment. It is a figure which shows an example of a wide angle image typically. It is a graph which shows the luminance distribution of the wide angle image about the light of a predetermined wavelength. It is a block diagram of an endoscope system to which a second embodiment according to the present invention is applied. It is a flowchart which shows the process sequence of the visual field position change in 2nd Embodiment. It is a figure which shows an example of a wide angle image typically. It is a graph which shows the luminance distribution of the wide angle image obtained in the visual field position change process of 2nd Embodiment. It is a figure which shows the modification of the position detection mark formed in forceps.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Rigid endoscope 20 Image separation device 21 Branch optical system 22 Wide angle optical system 23 Wide angle CCD camera 24 Reflective prism 25 Magnification optical system 26 Shift optical system 27 Focusing lens 28 Zooming lens group 31, 32 External monitor 40 Forceps 42, 51 , 52, 53 Position detection mark

Claims (9)

First imaging means for capturing a wide-angle image formed by the objective optical system;
A second photographing means for photographing an enlarged image of a partial region of the wide-angle image;
Wide-angle image display means for displaying the wide-angle image photographed by the first photographing means;
Enlarged image display means for displaying the enlarged image taken by the second imaging means;
Tracking control means for changing the field of view of the enlarged image so that a treatment tool is included in the enlarged image;
The treatment tool has a high-luminance portion in which a luminance value for a color of a predetermined wavelength is photographed higher than other regions in the wide-angle image,
The tracking control means includes position detection means for detecting, as the position of the treatment tool, a region having a higher luminance than the other regions for the color of the predetermined wavelength in the wide-angle image, and the treatment detected by the position detection unit. An endoscope system, wherein a visual field position of the enlarged image is changed based on a position of a tool.   The high-intensity portion is formed by providing a fluorescent material that emits light of a color having a predetermined wavelength by being excited by light having a specific wavelength included in illumination light irradiated for photographing. The endoscope system according to claim 1. A filter that transmits light in the vicinity of the wavelength of light emitted by the fluorescent material;
A filter driving means for interposing the filter on an optical path of a light beam guided from the objective optical system, or retracting the optical path from the optical path;
The tracking control means controls the filter driving means, interposes the filter on the optical path, and obtains an image signal acquired by photographing a wide-angle image formed in that state by the first photographing means. The endoscope system according to claim 2, wherein the processing of the position detection unit is executed based on the processing.   The endoscope system according to claim 1, wherein the high-intensity portion is formed by applying a paint having a color having the predetermined wavelength. The first imaging means is a solid-state imaging device having a color chip filter;
The color of the predetermined wavelength is one of the color chip filters,
The endoscope system according to claim 4, wherein the position detection unit extracts a signal obtained from a pixel corresponding to the color chip filter having the color of the predetermined wavelength.   The high-brightness portion is formed by providing a phosphorescent substance that accumulates light energy during external light irradiation and emits light based on the stored light energy when external light irradiation is stopped. The endoscope system according to claim 1.   The endoscope system according to claim 6, wherein the tracking control unit executes the processing of the position detection unit in a state where irradiation of illumination light for photographing is stopped.   The endoscope system according to claim 1, further comprising an operation member for instructing start and stop of processing of the tracking control unit.   The endoscope system according to claim 1, wherein the treatment instrument has a plurality of the high-luminance portions, and a geometric shape formed by the plurality of high-luminance portions is held in a storage unit. .

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