JP2011098169A - Confocal endomicroscopy and confocal endomicroscopy system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a confocal endomicroscopy structured suitable for a design for miniaturization. <P>SOLUTION: The confocal endomicroscopy has a structure including: of a point-light-source supporting means to support the prescribed point light-source movably in a two-dimensional direction; a confocal pinhole arranged in the position common to the focal point of light radiated from the point light-source; a holding means to hold the point-light-source supporting means movably in an orthogonal direction orthogonal to the two-dimensional direction together with the confocal pinhole; a first reflection plane supported by the point-light-source supporting means, and reflecting some of the prescribed measurement light; a second reflection plane supported by the holding means, and reflecting at least some of the measurement light penetrating the first reflection plane; and a reflected-light transmission means to transmit the reflected light, which is reflected at the first and second reflection planes to a prescribed photodetector. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention provides a confocal endoscope system for detecting and imaging only light through a pinhole arranged at a position conjugate with a focal position of a confocal optical system among return light from an irradiated subject, And a confocal endoscope apparatus included in the confocal endoscope system.

  In recent years, a so-called confocal endoscope system including a confocal optical system is known as a confocal endoscope system for observing living tissue in a body cavity. The confocal endoscope system irradiates a subject with irradiation light. In the confocal endoscope system, only light via a pinhole arranged at a position conjugate with the focal position of the confocal optical system is detected by the photodetector among the return light from the irradiated subject. The confocal endoscope system generates an image with a higher magnification and higher resolution than an image observed with a normal electronic scope or fiberscope based on a signal generated according to the intensity of detection light in a photodetector. . A specific configuration example of this type of confocal endoscope system is described in Patent Document 1.

  The confocal endoscope system described in Patent Literature 1 includes an XY scanning mechanism that vibrates in the two-dimensional direction the vicinity of the tip of an optical fiber that transmits illumination light to the subject and its return light. The XY scanning mechanism is configured to advance and retract in the Z-axis direction together with the optical fiber functioning as a point light source by a Z-axis actuator. That is, the confocal endoscope system described in Patent Document 1 is configured to scan the subject three-dimensionally by moving the optical fiber in the two-dimensional direction and moving it back and forth in the Z-axis direction.

  The Z-axis actuator has a shape memory alloy that contracts in the Z-axis direction when heated by energization. When the shape memory alloy is energized to contract the shape memory alloy in the Z-axis direction, the XY scanning mechanism is pulled by the shape memory alloy and retracts in the Z-axis direction. The XY scanning mechanism moves forward by being pushed out in the Z-axis direction by the urging force of the spring when the shape memory alloy returns to room temperature when the energization is stopped and there is no shape restoration due to the shape memory effect. The amount of movement of the XY scanning mechanism in the Z-axis direction is detected from the amount of change in capacitance of a double-wire coil capacitive sensor in which two wires are brought close to each other with an adhesive and wound in a coil shape.

JP 2004-321792 A

  This type of confocal endoscope system is constantly required to have a small insertion tip in order to achieve minimal invasiveness to a patient. However, a sensor for detecting the amount of movement, such as a double-wire coil capacitive sensor, has a limit in miniaturization because of its structure, and is a factor that hinders miniaturization of the insertion tip.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a confocal endoscope apparatus having a configuration suitable for downsizing design, and a confocal endoscope having the confocal endoscope apparatus. An endoscope system is provided.

  A confocal endoscope apparatus according to an aspect of the present invention that solves the above problems includes a point light source support unit that supports a predetermined point light source so as to be movable in a two-dimensional direction, and a collection of light emitted from the point light source. A confocal pinhole arranged at a position conjugate with the light spot, a holding means for holding the point light source support means movably in the orthogonal direction perpendicular to the two-dimensional direction together with the confocal pinhole, and a point light source support means A first reflection surface that reflects a part of the predetermined measurement light, and a second reflection surface that is supported by the holding means and reflects at least a part of the measurement light transmitted through the first reflection surface; And a reflected light transmitting means for transmitting the reflected light reflected by the first and second reflecting surfaces to a predetermined photodetector.

  That is, according to the present invention, the first and second reflecting surfaces are added to the point light source support unit and the holding unit, respectively, and according to the amount of movement of the point light source support unit in the orthogonal direction with respect to the holding unit. Output (reflected light reflected by the first and second reflecting surfaces) can be provided to an external photodetector.

  The point light source support means may have a first cylindrical member whose tip is sealed with a first cover glass having a first reflecting surface and which houses the point light source. The holding means may include a second cylindrical member whose tip is sealed with a second cover glass having a second reflecting surface, and the first cylindrical member is accommodated coaxially therein.

  The light source support means may be configured to support the vicinity of the exit end of the confocal optical fiber that transmits light supplied from a predetermined light source so as to be movable in a two-dimensional direction. It is desirable that the exit end be disposed at a position conjugate with the condensing point so as to function as a point light source and a confocal pinhole.

  The confocal endoscope apparatus according to the present invention may further include a measurement optical fiber that transmits measurement light supplied from a predetermined measurement light source toward the first and second reflection surfaces. In this case, it is desirable that the reflected light transmission means also serves as a measurement optical fiber.

  The confocal optical fiber and the measurement optical fiber may be shared by a single optical fiber.

  A confocal endoscope system according to an aspect of the present invention that solves the above-described problems is a confocal endoscope device according to any one of the above, and a reflection reflected by each of the first and second reflecting surfaces. A system comprising: a reflected light detecting means for detecting light; and a movement amount detecting means for detecting a movement amount of the point light source support means in the orthogonal direction with respect to the holding means based on a detection result of the reflected light detection means. It is.

  The movement amount detection means includes analysis means for analyzing the spectral interference waveform of the reflected light reflected by each of the first and second reflecting surfaces, and movement amount calculation means for calculating the movement amount based on the analyzed spectral interference waveform. It is good also as a structure which has.

  The movement amount detection means moves based on the timing difference detection means for detecting the difference in detection timing of the reflected light reflected by each of the first and second reflection surfaces and the detected timing difference. A movement amount calculating unit that calculates the amount may be included.

  The confocal endoscope system according to the present invention, in order to be able to easily reproduce the previous diagnostic conditions, position information storage means for storing the current position information in the orthogonal direction of the point light source support means with respect to the holding means, A configuration may further include position information specifying means for specifying the stored position information, and designated position moving means for moving the point light source support means to the position specified by the position information.

  The confocal endoscope system according to the present invention includes an image signal detection unit that receives light through the confocal pinhole and detects an image signal, and each detection timing of the image signal by the image signal detection unit The pixel arrangement of the two-dimensional plane for the image signal is determined, and the pixel arrangement in the depth direction orthogonal to the two-dimensional plane for each of the image signals is determined according to the movement amount detected by the movement amount detection means. A configuration may further include pixel arrangement determining means and image creating means for spatially arranging image information represented by each image signal in accordance with the determined pixel arrangement to create a subject image.

  ADVANTAGE OF THE INVENTION According to this invention, the confocal endoscope apparatus of a structure suitable for a miniaturization design and the confocal endoscope system which has this confocal endoscope apparatus are provided.

It is a figure showing roughly the composition of the confocal endoscope system of the embodiment of the present invention. It is a figure which shows schematically the structure of the confocal optical unit integrated in the insertion front-end | tip part of the electronic scope which the confocal endoscope system of embodiment of this invention has. It is a figure which expands and shows schematic structure of the front end side of the confocal optical unit of embodiment of this invention. It is a flowchart which shows the movement amount detection process which detects the movement amount of the Z-axis direction of the point light source which comprises the confocal optical system of embodiment of this invention. It is a figure which shows schematically the structure of the confocal endoscope system of another embodiment.

  Hereinafter, a confocal endoscope system according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram schematically illustrating a configuration of a confocal endoscope system 1 according to the present embodiment. As shown in FIG. 1, the confocal endoscope system 1 includes an electronic scope 100 for photographing a subject. The electronic scope 100 includes an insertion flexible tube 11 covered with a flexible sheath 11a. Connected to the distal end of the insertion flexible tube 11 is an insertion distal end portion 12 covered with a rigid resin casing. The bending portion 14 at the connection point between the insertion flexible tube 11 and the insertion distal end portion 12 is operated remotely from the hand operating portion 13 connected to the proximal end of the insertion flexible tube 11 (specifically, the bending operation knob). 13a), and can be bent freely. This bending mechanism is a well-known mechanism incorporated in a general electronic scope, and is configured to bend the bending portion 14 by pulling the operation wire in conjunction with the rotation operation of the bending operation knob 13a. By changing the direction of the insertion tip 12 according to the bending operation by the above operation, the imaging region by the electronic scope 100 moves.

  The confocal endoscope system 1 includes two imaging systems. One is an imaging system similar to a general endoscope imaging system (hereinafter, referred to as “first imaging system”) that images a subject with standard magnification and resolution. The other is an imaging system (hereinafter referred to as “second imaging system”) that images a subject at a higher magnification and higher resolution than the first imaging system. First, the first imaging system will be described.

  The confocal endoscope system 1 has a first processor 200 that constitutes a first imaging system. The first processor 200 is an apparatus that integrally includes a light source device 202 that illuminates a body cavity that does not reach natural light via the electronic scope 100, and a signal processing device 204 that processes an imaging signal from the electronic scope 100. . In another embodiment, the light source device 202 and the signal processing device 204 may be configured separately. The electronic scope 100 is electrically and optically connected to the first processor 200 via the first universal cable 15.

  Illumination light emitted from the light source device 202 is limited to an appropriate amount of light through a diaphragm mechanism (not shown) and enters an incident end of an LCB (light carrying bundle) 102 included in the electronic scope 100. The appropriate reference for the brightness of the image is changed according to the brightness adjustment operation of the front panel 206 by the operator.

  The LCB 102 is disposed at a position where the incident end is coupled to the light source device 202, and the emission end is disposed at the insertion tip portion 12. The illumination light incident on the incident end of the LCB 102 propagates by repeating total reflection inside the LCB 102 and exits from the exit end. The insertion tip 12 incorporates a light distribution lens 104, an objective lens 106, and a solid-state image sensor 108 that constitute a first imaging system. The illumination light emitted from the exit end illuminates the subject via the light distribution lens 104. The reflected light from the subject forms an optical image on the light receiving surface of the solid-state image sensor 108 via the objective lens 106.

  The solid-state imaging device 108 is, for example, a single-plate color CCD (Charge Coupled Device) having a Bayer-type pixel arrangement, and is driven at a timing synchronized with a video frame rate in accordance with a clock pulse supplied from the first processor 200. The solid-state image sensor 108 accumulates an optical image formed by each pixel on the light receiving surface as a charge corresponding to the amount of light, and converts it into a signal corresponding to each color of R, G, and B. The converted signal is input to the signal processing device 204 via an insulating circuit (not shown) using a photocoupler or the like.

  The signal processing device 204 performs predetermined signal processing such as clamping, knee, γ correction, interpolation processing, AGC (Auto Gain Control), AD conversion, and the like on the output signal of the solid-state imaging device 108, and the processed signal is illustrated in the figure. Buffer in frame memory in omitted frame memory. The buffered signal is swept from the frame memory at a predetermined timing, and converted into a video signal conforming to a predetermined standard such as NTSC (National Television System Committee) or PAL (Phase Alternating Line). By sequentially inputting the converted video signals to the monitor 200M, a color image of a subject with standard magnification and resolution is displayed on the monitor 200M.

  Next, the second imaging system will be described. The second imaging system has a confocal optical unit 120 incorporated in the insertion tip 12. The confocal optical unit 120 is a unit designed by applying the principle of a confocal microscope, and is preferably configured to observe a subject with high magnification and high resolution. The confocal observation using the second imaging system is performed in a state where the end surface 12a of the insertion tip portion 12 located on the front surface of the confocal optical unit 120 is applied to the subject. On the other hand, when normal observation is performed using the first imaging system, in order to obtain a clear subject image without blurring, the arrangement surface of the objective lens 106 (the end surface 12b of the insertion tip 12 in FIG. 1) is, for example, It is necessary to move away from the subject by an amount corresponding to the focal length of the objective lens 106. Therefore, the distal end surface of the insertion distal end portion 12 is formed such that the end surface 12a is positioned to protrude from the end surface 12b by a predetermined amount. Therefore, when the end surface 12a is applied to the subject, the objective lens 106 is stabilized at a position where the subject is within the depth of field.

  The confocal endoscope system 1 has a second processor 300 that constitutes a second imaging system. The electronic scope 100 is electrically and optically connected to the second processor 300 via the second universal cable 16.

  The second processor 300 includes a laser light source 302 that emits laser light having a wavelength that acts as excitation light on the subject. Laser light (for example, wavelength: 488 nm) emitted from the laser light source 302 propagates through the optical fiber 304 and enters the incident end of the optical fiber 122 via the photocoupler 306.

  FIG. 2 is a diagram schematically showing the configuration of the confocal optical unit 120 incorporated in the insertion tip portion 12. In the following, in describing the configuration of the confocal optical unit 120, for convenience, the longitudinal direction of the confocal optical unit 120 is defined as the Z direction, and two directions orthogonal to the Z direction and orthogonal to each other are defined as the X direction and the Y direction. It is defined as

  As shown in FIG. 2, the confocal optical unit 120 has a metal outer cylinder 124 that houses various components of the unit. The outer cylinder 124 holds an inner cylinder 126 having an outer wall surface shape corresponding to the inner wall surface shape of the outer cylinder 124 so as to be coaxial and slidable in the Z-axis direction. The exit end 122a of the optical fiber 122 is supported inside the inner cylinder 126 through openings formed in the base end surfaces of the outer cylinder 124 and the inner cylinder 126, and serves as a secondary point light source of the second imaging system. Function.

  The outer cylinder 124 has an objective optical system 128. The objective optical system 128 includes a plurality of optical lenses held in a lens frame (not shown). The lens frame is fixed and supported relative to the inner cylinder 126 inside the outer cylinder 124. Therefore, the optical lens group held in the lens frame slides in the Z-axis direction integrally with the inner cylinder 126 inside the outer cylinder 124.

  The vicinity of the exit end 122a of the optical fiber 122 is vibrated by a piezoelectric actuator (not shown). The piezoelectric actuator is driven and controlled by a controller 308 included in the second processor 300. The injection end 122a periodically moves on the XY plane (strictly speaking, a curved surface approximating the XY plane) by vibrations from the piezoelectric actuator. The laser beam emitted from the emission end 122a is focused on the objective optical system 128, and the subject is two-dimensionally scanned as the emission end 122a moves on the XY plane. Note that the radius of curvature of the moving curved surface of the injection end 122a is extremely large. Therefore, even if the moving curved surface of the injection end 122a is regarded as the XY plane, there is substantially no problem.

  The confocal optical unit 120 has a compression coil spring 130 between the base end surface of the inner cylinder 126 and the inner wall surface of the outer cylinder 124. The compression coil spring 130 is sandwiched between the base end face of the inner cylinder 126 and the inner wall surface of the outer cylinder 124 in an initially compressed state from the natural length in the Z-axis direction.

  The confocal optical unit 120 has a rod-shaped shape memory alloy 132 that is long in the Z-axis direction. The shape memory alloy 132 has one end fixed to the base end surface of the inner cylinder 126 and the other end fixed to the inner wall surface of the outer cylinder 124. The shape memory alloy 132 has a property of deforming when an external force is applied at room temperature and restoring a predetermined shape by the shape memory effect when heated to a certain temperature or higher.

  The shape memory alloy 132 extends in the Z-axis direction by applying the restoring force of the compression coil spring 130 at room temperature. The shape memory alloy 132 is designed such that the restoring force due to the shape memory effect is larger than the restoring force of the compression coil spring 130.

  The shape of the shape memory alloy 132 is controlled by heating the shape memory alloy 132 itself by energizing the shape memory alloy 132 from the controller 308. Specifically, when the shape memory alloy 132 is heated by energization, it contracts in the Z-axis direction against the restoring force of the compression coil spring 130. As the shape memory alloy 132 contracts, the inner cylinder 126 fixed to one end of the shape memory alloy 132 moves backward in the Z-axis direction along with the optical fiber 122 supported by the inner cylinder 126. The amount of contraction of the shape memory alloy 132 is precisely controlled by the amount of current supplied to the shape memory alloy 132. This energization amount (in other words, the amount of movement of the optical fiber 122 in the Z-axis direction) varies according to the adjustment operation of the Z-axis movement amount of the hand operation unit 13 by the operator.

  When the shape memory alloy 132 stops energization and returns to normal temperature (or the temperature decreases due to a decrease in the energization amount), the restoring force due to the shape memory effect disappears (or becomes weak), and the restoring force of the compression coil spring 130 Extends in the Z-axis direction. The base end surface of the inner cylinder 126 is pushed by the restoring force of the compression coil spring 130, and moves forward in the Z-axis direction together with the optical fiber 122 in the outer cylinder 124.

  The laser beam emitted from the emission end 122a of the optical fiber 122 is focused on the surface or surface layer of the subject via the objective optical system 128. This focal position is displaced in the Z-axis direction in accordance with the advance and retreat of the emission end 122a that is a point light source. That is, the confocal optical unit 120 performs the tertiary movement of the subject by performing the biaxial movement of the ejection end 122a by the piezoelectric actuator and the uniaxial movement of the ejection end 122a by the compression coil spring 130 and the shape memory alloy 132. Perform original scan.

  The exit end 122 a of the optical fiber 122 is disposed at the front focal position of the objective optical system 128. Therefore, the exit end 122a functions as a confocal pinhole. That is, only the fluorescence from the condensing point optically conjugate with the exit end 122a is incident on the exit end 122a among the scattered components (fluorescence) of the subject illuminated by the laser light.

  The fluorescence that has entered the exit end 122 a of the optical fiber 122 propagates inside the optical fiber 122. The fluorescence propagated inside the optical fiber 122 is separated from the laser light from the laser light source 302 by the photocoupler 306, and then detected by the photodetector 314 through the optical fiber 312. This detection signal is input to the image generation circuit 316. The image generation circuit 316 assigns a pixel address to a point image represented by each detection signal according to the detection timing of the detection signals that are sequentially input. The image generation circuit 316 buffers an image signal constituted by the spatial arrangement of each point image in the frame memory according to the assigned pixel address in the frame memory. The buffered signal is swept from the frame memory at a predetermined timing, and converted into a video signal conforming to a predetermined standard such as NTSC or PAL. By sequentially inputting the converted video signal to the monitor 300M, a high-magnification and high-resolution three-dimensional confocal image of the subject is displayed on the monitor 300M.

  Here, in order to improve the magnification or resolution of the three-dimensional confocal image, it is indispensable to finely move the point light source that is a component of the confocal optical system in the Z-axis direction. This is achieved by finely controlling the amount of current supplied to the shape memory alloy 132 and finely moving the exit end 122a of the optical fiber 122. However, in order to improve the magnification or resolution of a three-dimensional confocal image, it is not enough to increase the resolution of the moving mechanism, but the actual moving amount (or position) is detected and the moving mechanism is feedback-controlled with high accuracy. Therefore, it is necessary to improve the resolution of the movement amount detection mechanism. The present applicant has focused on this point and recalled a movement amount detection mechanism suitable for the confocal optical unit 120.

  The following is a description of the movement amount detection mechanism mounted on the confocal endoscope system 1 of the present embodiment. As shown in FIG. 1, the second processor 300 has a light source 320. The light source 320 is, for example, an SLD (Super luminescent Diode) light source that emits light in a wide wavelength band, and emits measurement light for measuring the amount of movement of the emission end 122a of the optical fiber 122 in the Z-axis direction. As the wavelength band of the measurement light, a range that does not overlap any wavelength band of the light emitted from the laser light source 302 or the reflected light (fluorescence) from the subject is selected. The measurement light is emitted from the light source 320 and then enters the incident end of the optical fiber 122 via the half mirror 322 and the photocoupler 306. The measurement light propagates by repeating total reflection inside the optical fiber 122 and exits from the exit end 122a.

  FIG. 3 is an enlarged view showing a schematic configuration of the front end side of the confocal optical unit 120. As shown in FIG. 3, the tip of the inner cylinder 126 is sealed with a cover glass CG1. A predetermined reflection filter R1 is coated on the surface of the cover glass CG1 on the optical fiber 122 side. The tip of the outer cylinder 124 is sealed with a cover glass CG2. A surface of the cover glass CG2 on the objective optical system 128 side is coated with a predetermined reflection filter R2. The reflection filters R1 and R2 have the same reflection characteristic that transmits light in a wavelength band other than the measurement light while reflecting the measurement light. In other words, the reflection filters R1 and R2 reflect the measurement light, but do not reduce the light use efficiency of the second imaging system. Therefore, the reflection light from the laser light source 302 or the reflected light (fluorescence) from the subject is substantially 100. % Transmission.

  A part of the measurement light emitted from the emission end 122a of the optical fiber 122 is reflected by the reflection filter R1, and the remainder transmitted through the reflection filter R1 is reflected by the reflection filter R2. The measurement light reflected by each reflection filter returns to the optical path while interfering with each other, and enters the spectroscope 324 via the photocoupler 306 and the half mirror 322.

  The spectroscope 324 includes a spectroscopic element such as a diffraction grating and a solid-state image sensor such as a CCD. The interference light incident on the spectroscope 324 is separated by wavelength by the spectroscopic element and then detected by the solid-state image sensor. The signal detected by the solid-state imaging device represents the interference light intensity distribution of the wavelength, and changes according to the distance (distance D in FIG. 3) between the reflection filter R1 and the reflection filter R2. The waveform analysis circuit 326 analyzes the interference light intensity distribution of this wavelength and outputs it to the controller 308. The controller 308 calculates the distance D based on the input analysis result. The controller 308 detects the amount of movement of the inner cylinder 126 from the comparison between the calculated distance D and the previous distance D. Alternatively, the current position of the inner cylinder 126 is detected from the calculated distance D. The controller 308 compares the detected amount of movement with the target amount of movement to control the amount of energization to the shape memory alloy 132 and finely moves the inner cylinder 126 in the Z-axis direction.

  FIG. 4 is a flowchart showing a movement amount detection process for detecting the movement amount in the Z-axis direction of the point light source (the exit end 122a of the optical fiber 122) constituting the confocal optical system. The movement amount detection process of FIG. 4 is started when the confocal endoscope system 1 is started and the power of the confocal endoscope system 1 is turned off, or the confocal endoscope system 1 It ends when it stops. In the following description and drawings in this specification, the processing step is abbreviated as “S”.

  The light source 320 emits measurement light, for example, when the confocal endoscope system 1 is activated. Therefore, the analysis of the interference light intensity distribution is performed immediately after the confocal endoscope system 1 is activated. The controller 308 receives the analysis result from the waveform analysis circuit 326, and detects the current position of the inner cylinder 126 in the Z-axis direction (S1).

  Next, the controller 308 moves the inner cylinder 126 to the home position (S2). The home position is set to the center position of the maximum range where the inner cylinder 126 can be moved with respect to the outer cylinder 124 by hardware, for example, at the time of product shipment. However, the home position can be arbitrarily set and changed by the operator operating the front panel 310 or the hand operation unit 13. The home position setting value is stored in a memory 318 included in the second processor 300. At this time, the set value of the home position is stored in association with the ID of the electronic scope 100 and is retained even after the power is turned off. The ID referred to here is identification information such as a model number read in advance from a memory (not shown) of the electronic scope 100 by the controller 308 when the system is activated.

  In the process of S2, the controller 308 moves the inner cylinder 126 until the position set as the home position is detected. After moving to the home position, the inner cylinder 126 moves according to a manual operation by the operator or according to a setting (a user setting position described later) stored in the memory 318. The movement of the inner cylinder 126 in the processes after S3 is a movement that assumes imaging of a three-dimensional confocal image by the second imaging system.

  The inner cylinder 126 is finely advanced or retracted within a predetermined movable range in accordance with the operation of the hand operation unit 13 by the operator (S3: manual operation, S4). The predetermined movable range is a range that is more limited than a hardware movable range by software processing in consideration of machining errors and assembly errors of various parts. The controller 308 sequentially outputs the detected movement amount to the image generation circuit 316. The image generation circuit 316 determines a pixel address in the subject depth direction for each point image according to the amount of movement. Thereby, a high-definition confocal image corresponding to the minute movement amount of the inner cylinder 126 (point light source) is generated and displayed on the monitor 300M.

  The surgeon can operate the front panel 310 or the hand operation unit 13 to register the current position of the inner cylinder 126 in the Z-axis direction (hereinafter referred to as “user setting position”). Specifically, when accepting an operation for registering the user setting position (S5: YES), the controller 308 stores the distance D corresponding to the current position in the memory 318 as the user setting position (S6). At this time, the user setting position is stored in association with the ID of the electronic scope 100 and is retained even after the power is turned off. A plurality of user-set positions can be registered for one electronic scope 100.

  When there is no user setting position registration operation (S5: NO), or after the user setting position registration process of S6, the process returns to S3. The surgeon can operate the front panel 310 or the hand operation unit 13 to move the inner cylinder 126 to the user setting position. Specifically, when the controller 308 receives a movement operation to the user setting position (S3: user setting position designation operation), the controller 308 performs the movement process of S7. In the movement process of S7, the distance D corresponding to the designated user setting position is read from the memory 318. The read distance D is compared with the currently calculated actual distance D, and the difference is calculated. The controller 308 moves the inner cylinder 126 by the direction and amount in which this difference is eliminated. By such a simple operation, the surgeon can observe the subject confocally, for example, at the same depth as in the previous diagnosis.

  As described above, the user setting position is registered and managed for each electronic scope. However, when using another device, there may be a situation where the subject wants to observe the subject at the same depth as when using the other device. In this case, the user-set position associated with the ID of the other device may be used by another device so that the subject can be confocally observed at the same depth as when the other device is used.

  According to the confocal endoscope system 1 of the present embodiment, a point light source can be used without substantial increase in parts by using a cover glass which is an indispensable existing component for sealing each tube. A configuration for detecting the amount of movement in the Z-axis direction can be incorporated in the insertion tip portion 12. That is, a dedicated part for detecting the amount of movement, such as a double-wire coil capacitive sensor, is not necessary, and the insertion tip 12 can be easily downsized.

  The above is the description of the embodiment of the present invention. The present invention is not limited to the above-described configuration, and various modifications can be made within the scope of the technical idea of the present invention. For example, the reflection filter R1 or R2 is not limited to the arrangement of the present embodiment. For example, the reflection filter R2 may be disposed between the objective optical system 128 and the cover glass CG1.

  The detection of the movement amount of the inner cylinder 126 is not limited to the detection method of the present embodiment using the principle of spectral interference method. FIG. 5 schematically shows a configuration of a confocal endoscope system 1z according to another embodiment that detects the amount of movement of the inner cylinder 126 by another method. As shown in FIG. 5, the confocal endoscope system 1 z has a photodetector 328 instead of the spectroscope 324 and the waveform analysis circuit 326 as a block configuration.

  In another embodiment, the light source 320 emits one pulse of measurement light (modulated light) in a wavelength band of, for example, 800 nm to 1000 nm. The reflection filter R1 has a characteristic of reflecting only a wavelength band of 850 nm to 900 nm (hereinafter referred to as “first wavelength band”), for example. For this reason, only the light of the first wavelength band in the measurement light is reflected by the reflection filter R1. Measurement light in the remaining wavelength band passes through the reflection filter R1 and enters the reflection filter R2. The reflection filter R2 has a characteristic of reflecting only a wavelength band of 950 nm to 1000 nm (hereinafter referred to as “second wavelength band”), for example. Therefore, only the light in the second wavelength band of the measurement light is reflected by the reflection filter R2. Note that measurement light other than the first or second wavelength band reaches the subject and is scattered. However, a range that does not overlap any of the wavelength band of the light emitted from the laser light source 302, the wavelength band of the reflected light (fluorescence) from the subject, and the visible range is selected as the wavelength band of the measurement light. Therefore, the measurement light scattered by the subject does not substantially affect the color image or confocal observation image of the subject.

  The reflected light in the first and second wavelength bands reflected by each reflection filter returns through the optical path without interference, and is detected by the photodetector 328 via the photocoupler 306 and the half mirror 322. In other words, the reflected light in the second wavelength band is delayed from the reflected light in the first wavelength band by an optical path length difference that reciprocates between the reflective filter R1 and the reflective filter R2. That is, as the distance D increases, the difference in the detection timing of the reflected light in the first and second wavelength bands in the photodetector 328 increases. The controller 308 calculates the distance D according to this detection timing difference, and detects the movement amount or the current position of the inner cylinder 126.

  In another embodiment, there is an advantage that the movement amount or the current position of the inner cylinder 126 can be detected immediately by simply reflecting one pulse of measurement light by each reflection filter. Since the photodetector 328 having a simple configuration can be used for detecting the timing difference of the reflected light, it is advantageous in terms of manufacturing cost.

DESCRIPTION OF SYMBOLS 1 Confocal endoscope system 12 Insertion front-end | tip part 100 Electronic scope 120 Confocal optical unit 124 Outer cylinder 126 Inner cylinder 130 Compression coil spring 132 Shape memory alloy 308 Controller 324 Spectrometer 326 Wavelength analysis circuit R1, R2 Reflection filter

Claims (10)

Point light source support means for supporting a predetermined point light source movably in a two-dimensional direction;
A confocal pinhole disposed at a position conjugate with the condensing point of the light emitted from the point light source;
Holding means for holding the point light source support means together with the confocal pinhole so as to be movable in an orthogonal direction orthogonal to the two-dimensional direction;
A first reflection surface that is supported by the point light source support means and reflects a part of the predetermined measurement light;
A second reflecting surface that is supported by the holding means and reflects at least a part of the measurement light that has passed through the first reflecting surface;
Reflected light transmitting means for transmitting the reflected light reflected by the first and second reflecting surfaces to a predetermined photodetector;
A confocal endoscope apparatus characterized by comprising: The point light source support means is
A first tubular member having a tip sealed with a first cover glass having the first reflecting surface and containing the point light source therein;
Have
The holding means is
A second cylindrical member whose front end is sealed with a second cover glass having the second reflecting surface, and the first cylindrical member is accommodated coaxially therein;
The confocal endoscope apparatus according to claim 1, comprising: The point light source support means supports the vicinity of the exit end of a confocal optical fiber that transmits light supplied from a predetermined light source so as to be movable in the two-dimensional direction,
The coexistence according to claim 1 or 2, wherein the exit end is arranged at a position conjugate with the condensing point so as to function as the point light source and the confocal pinhole. Focal endoscope device. A measurement optical fiber that transmits the measurement light supplied from a predetermined measurement light source toward the first and second reflection surfaces;
Further comprising
The confocal endoscope apparatus according to any one of claims 1 to 3, wherein the reflected light transmission unit also serves as the measurement optical fiber.   The confocal endoscope apparatus according to claim 4, wherein the confocal optical fiber and the measurement optical fiber are shared by a single optical fiber. The confocal endoscope apparatus according to any one of claims 1 to 5,
Reflected light detecting means for detecting reflected light reflected by the first and second reflecting surfaces;
Based on the detection result of the reflected light detection means, a movement amount detection means for detecting the movement amount of the point light source support means relative to the holding means in the orthogonal direction;
A confocal endoscope system comprising: The movement amount detecting means includes
Analyzing means for analyzing a spectral interference waveform of reflected light reflected by the first and second reflecting surfaces;
A moving amount calculating means for calculating the moving amount based on the analyzed spectral interference waveform;
The confocal endoscope system according to claim 6, comprising: The movement amount detecting means includes
A timing difference detecting means for detecting a difference in detection timing of the reflected light reflected by the first and second reflecting surfaces by the reflected light detecting means; and
A movement amount calculating means for calculating the movement amount based on the detected timing difference;
The confocal endoscope system according to claim 6, comprising: Position information storage means for storing current position information in the orthogonal direction of the point light source support means with respect to the holding means;
Position information specifying means for specifying the stored position information;
Designated position moving means for moving the point light source support means to a position designated by the position information;
The confocal endoscope system according to any one of claims 6 to 8, further comprising: Image signal detection means for detecting an image signal by receiving light through the confocal pinhole;
According to the detection timing of the image signal by the image signal detection means, a pixel arrangement of a two-dimensional plane for each image signal is determined, and according to the movement amount detected by the movement amount detection means, Pixel arrangement determining means for determining a pixel arrangement in the depth direction orthogonal to the two-dimensional plane for the image signal;
Image creation means for creating a subject image by spatially arranging image information represented by each of the image signals according to the determined pixel arrangement;
The confocal endoscope system according to any one of claims 6 to 9, further comprising:

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