JP2007068896A - Fluorescence endoscope system - Google Patents

Abstract

Provided is a fluorescence endoscope system capable of reliably preventing unintended excitation light from being guided to a socket without being affected by noise generated in a light source device.
A main controller 24 selectively emits excitation light from an excitation light source 23 by controlling an excitation light source drive control circuit 43. The sub-controller 40 built in the endoscope 10 periodically communicates with the main controller 24 and sends a shutter open signal to the shutter drive circuit 21 as long as there is a normal response from the main controller 24. As long as a shutter open signal is received, the shutter drive circuit 21 supplies a drive current to the solenoid 22 and opens the open / close shutter 39 in the optical path of the excitation light from the excitation light source 23.
[Selection] Figure 2

Description

  The present invention relates to a fluorescence endoscope system capable of introducing excitation light for fluorescence excitation from a light source device to a light guide in an endoscope.

  As is well known, biological tissue is excited and emits fluorescence when irradiated with light of a specific wavelength. In addition, an abnormal living tissue in which a lesion such as a tumor or cancer has occurred emits weaker fluorescence than a normal living tissue. This reaction phenomenon can also be caused by living tissue below the body cavity wall. In recent years, endoscope systems have been developed that detect abnormalities occurring in a living tissue under a body cavity wall using this reaction phenomenon.

  As one of this type of endoscope system, the inside of a body cavity is illuminated by emitting illumination light in the visible band from the distal end of the endoscope, and an image of the reflected light of the illumination light on the inner wall surface of the body cavity is captured by an imaging device. In addition to the normal observation mode for imaging, light of a specific wavelength band that excites the living tissue is emitted from the tip of the endoscope, and an image of fluorescence emitted from the living tissue under the inner wall of the body cavity excited by this light is captured There is a fluorescence endoscope system that operates in a fluorescence observation mode in which an image is captured by the apparatus.

  The light source device used in such a fluorescence endoscope system includes illumination light (white light) emitted from a visible light source together with a visible light source (for example, a halogen lamp) and an excitation light source (for example, a semiconductor laser). And an optical path synthesizing element (half mirror, dichroic mirror, quick return mirror, etc.) for synthesizing the optical path of the above and the optical path of excitation light (light of a specific wavelength in the blue to ultraviolet band) emitted from the excitation light source. The light source processor device excites illumination light emitted from the visible light source in the normal observation mode to the light guide fiber bundle of the endoscope inserted into the socket formed on the side wall in the fluorescence observation mode. Excitation light emitted from a light source for light is introduced through an optical path synthesis element.

  The illumination light or excitation light thus introduced into the light guide is guided by this light guide, passes through the body cavity insertion section through the operation section from the light guide flexible tube of this endoscope, and is inserted into this body cavity. It is injected from the tip of the part. Therefore, when this body cavity insertion part is inserted into the body cavity of the subject, in the normal observation mode, an image of the inner wall of the body cavity due to the reflected light of the illumination light emitted from the distal end of the body cavity insertion part is obtained. In the fluorescence observation mode, the light is emitted from a living tissue under the inner wall of the body cavity excited by the excitation light emitted from the distal end of the body cavity insertion section. An image due to the fluorescence is captured by the imaging device.

  Image signals obtained by imaging in both modes are processed by an image processing circuit built in the light source device or an image processing device placed outside. In the normal observation mode, an image signal for displaying a color image with visible light on the inner wall of the body cavity is generated, and a color image of the inner wall of the body cavity is displayed on the monitor based on the image signal. On the other hand, in the fluorescence observation mode, an image signal for displaying the affected part in a specific color is generated, and a fluorescence image is displayed on the monitor based on the image signal. A doctor who is an operator of the endoscope can check the position of the affected part by comparing these images, and can perform various treatments for biopsy and treatment.

  By the way, since the excitation light emitted from the excitation light source is high energy light, for example, when the light guide of the endoscope is not inserted into the socket and is emitted toward the outside through the socket, the subject And medical staff such as doctors may cause visual impairment and burns. Even when the endoscope light guide is inserted into the socket, if the excitation light is introduced into the light guide against the surgeon's will, the same danger may occur. When the body cavity insertion portion is inserted into the body cavity of the subject, there may be a possibility of causing burns or canceration on the inner wall of the body cavity.

In view of this, a light source device in a conventional fluorescence endoscope system has a built-in mechanism that prevents the excitation light from being guided to the socket while the operator does not intend to emit the excitation light. Examples of such a mechanism include a control circuit that forcibly cuts off the drive current to the excitation light source, a shutter that blocks excitation light between the excitation light source and the socket, and a control circuit that drives the shutter. Used.
JP 07-005333 A JP-A-10-142449 JP 2002-071539 A

  However, since the light source lamp is a discharge lamp such as a halogen lamp and requires a high-voltage power supply, lighting noise can be generated from the power supply circuit including the booster circuit and the lamp itself. In addition, since a noise source such as an image processing circuit may be included in the light source processor device, the mechanism itself that prevents the excitation light from being guided to the socket may malfunction due to the noise. Sex cannot be denied. When such a malfunction occurs, it becomes impossible to prevent the occurrence of the failure as described above.

  Accordingly, an object of the present invention is to provide a fluorescence endoscope system that can reliably prevent unintended excitation light from being guided to a socket without being affected by noise generated in the light source device. Is to provide.

  The fluorescent endoscope system of the present invention devised to solve the above problems includes a long body cavity insertion portion that is inserted into a body cavity and through which a light guide is passed over the entire length thereof. A fluorescence endoscope system comprising: an endoscope having an endoscope; and a light source device that supplies excitation light that excites a living tissue to generate fluorescence to a light guide of the endoscope. A socket into which the proximal end of the light guide is inserted; an excitation light source that emits the excitation light; a shutter mechanism that opens an optical path of the excitation light only while a shutter open signal is input; An optical system that guides the excitation light to a proximal end of the light guide inserted into the socket, and a main controller that controls the excitation light source. The endoscope further includes the light guide. An objective optical system that connects an image due to fluorescence from a living tissue irradiated through the imaging device, an image sensor that captures the image connected by the objective optical system, and the main controller. As long as communication is performed and a response from the main controller is received, the shutter open signal is output to the shutter mechanism. If no response is received from the main controller, the shutter to the shutter mechanism is output. And a sub-controller that stops the output of the open signal.

  If comprised in this way, while the main controller incorporated in the light source device operates normally and the excitation light emission from the excitation light source can be controlled, it is incorporated in the endoscope. Since the sub-controller periodically communicates with the main controller and receives a response from the main controller, the sub-controller recognizes that the main controller is operating normally and sends a shutter open signal to the shutter mechanism. Continue sending. As long as this shutter open signal is received, the shutter mechanism keeps opening the optical path of the excitation light from the excitation light source, so if the excitation light source emits excitation light under the control of the main controller, this excitation light source The light is guided by the optical system and introduced into the proximal end of the endoscope light guide inserted in the socket. On the other hand, even if the main controller malfunctions due to noise generated in the light source device and the excitation light emission from the excitation light source falls into an uncontrollable state, the sub-controller is outside the light source device. It continues to operate normally without being affected by the noise. Accordingly, when the response from the main controller cannot be received, it is recognized that an abnormality has occurred in the main controller, and the output of the shutter open signal is stopped. Then, since the shutter mechanism closes the optical path of the excitation light, even if the main controller continues to emit the excitation light from the excitation light source due to malfunction, the excitation light does not reach the socket through the optical system.

  As described above, according to the fluorescence endoscope system of the present invention, it is possible to reliably guide the excitation light not intended by the operator to the socket without being affected by noise generated in the light source processor device. Can be prevented.

  Next, modes for carrying out the present invention will be described based on the attached drawings.

  FIG. 1 is an external view of a fluorescence endoscope system according to the present invention. As shown in FIG. 1, the fluorescence endoscope system includes a fluorescence observation endoscope 10, a light source processor device 20, and a monitor 60.

  The fluorescence observation endoscope 10 is obtained by adding a modification for fluorescence observation to a normal electronic endoscope, and is inserted into a body cavity. To connect the operation unit 10b, the operation unit 10b, and the light source processor device 20 having an angle knob and a plurality of operation buttons (only one operation button 10e is shown in FIG. 2) for bending the tip of the unit 10a. The light guide flexible tube 10c and the connector 10d provided at the base end of the light guide flexible tube 10c are provided.

  As shown in the schematic diagram of FIG. 2, an illumination window and a photographing window into which the light distribution lens 11 and the objective lens 12 are fitted are formed on the distal end surface of the body cavity insertion portion 10a. In the body cavity insertion portion 10 a, an image sensor 13 that captures an image of a subject formed by the objective lens 12, a cable driver 15 that processes an image signal output from the image sensor 13, and the objective lens 12. An excitation light cut filter 14 for removing a wavelength component corresponding to excitation light for fluorescence excitation, which will be described later, from light emitted from is incorporated.

  An image signal cable 18a for transmitting an image signal output from the image sensor 15 and processed by the cable driver 15 is passed through the body cavity insertion portion 10a, the operation portion 10b, and the light guide flexible tube 10c, It is connected to the image signal input terminal of the sub-controller 40 incorporated in the connector 10d.

  In parallel with the image signal cable 18a, in the body cavity insertion portion 10a, the operation portion 10b, and the light guide flexible tube 10c, a drive signal cable for supplying a drive signal to the light guide 16 and the image sensor 13 made of quartz fiber. 19 have been passed through, respectively.

  The distal end of the light guide 16 faces the light distribution lens 11 in the distal end portion of the body cavity insertion portion 10a, and the proximal end thereof is inserted into a metal pipe (not shown) protruding from the end face of the connector 10d and fixed. Has been.

  The distal end of the drive signal cable 19 is connected to the drive signal input terminal of the image sensor 13, and the base end thereof is a plurality of connector pins (not shown) constituting a signal connector (not shown) formed on the end face of the connector 10d. (Not shown).

  Furthermore, each operation button 10e of the operation unit 10b is connected to the operation signal input terminal of the sub-controller 40 through the operation signal cable 17a.

  The sub-controller 40 is a processing device having a plurality of functions. One of the functions of the sub-controller 40 is a function of sending an image signal input through the image signal cable 18a to the image signal cable 18b after performing image processing such as analog / digital conversion. Another one of the functions of the sub-controller 40 is a digital code signal indicating which button is pressed by analyzing the operation signals input from the plurality of operation buttons 10e through the operation signal cable 17a. Is generated and sent to the operation signal cable 17b. Still another of the functions of the sub-controller 40 is that the attributes of the fluorescence observation endoscope 10 (for example, the maximum amount of light that can be introduced into the light guide, the distinction of whether or not fluorescence observation is possible, etc.) ) Is stored, and the identification information is sent to the operation signal cable 17b. Further, another one of the functions of the sub-controller 40 detects a communication trouble described later only while the mode is switched to the fluorescence observation mode by the specific operation button 10e pressed for fluorescence observation. Unless otherwise specified, this is a function for generating a signal for opening the shutter (hereinafter referred to as “shutter opening signal”) and sending it to the shutter closing signal cable 41.

  Similarly to the drive signal cable 19 described above, the base ends of the cables 17b, 18b and 41 are also connected to any one of a plurality of connector pins constituting a signal connector (not shown) formed on the end surface of the connector 10d. ,It is connected.

  The normal electronic endoscope that can be used in exchange for the fluorescence observation endoscope 10 is such that the optical fiber constituting the light guide 16 is not a quartz fiber, the excitation light cut filter 14 is not provided, Except for the fact that the identification information stored in the sub-controller 17 indicates a normal electronic endoscope, and the absence of a function for outputting a shutter open signal, the same configuration as this fluorescence observation endoscope 10 have.

  The light source processor device 20 selectively introduces illumination light (white light) or excitation light into the end face of the light guide 16 of the endoscope (fluorescence observation endoscope 10), and also uses the endoscope (fluorescence observation endoscope). This is a device that generates a video signal by performing image processing on the image signal received from the sub-controller 40 through the electrical connector of 10) and outputs it to the monitor 60. A specific configuration of the light source processor device 20 will be described in more detail with reference to FIG. 2 showing a planar layout of the internal configuration.

  As shown in FIG. 2, the interior of the light source processor device 20 is divided into a light source unit 20b and an image processing unit 20c. Therefore, first, each element constituting the light source unit 20b will be described.

  As shown in FIG. 2, the light guide 16 of the endoscope (the fluorescence observation endoscope 10 or the electronic endoscope) is inserted into the front panel of the casing of the light source processor device 20 from the outer surface side. A socket 20a which is a hole is provided. The back side of the socket 20a corresponds to the light source unit 20b. On the extended line, a condenser lens 28, a dichroic mirror 29, a rotary shutter 27, a diaphragm 32, and a lamp 33 constituting the light source unit 20b are sequentially arranged. Is arranged.

  The condensing lens 28 is a lens that condenses the parallel light incident along the optical axis from the dichroic mirror 29 side on the base end surface of the light guide 16.

  The lamp 33 is supplied with a power supply current from a lamp power source 38 to emit white light (not shown), and a lens or reflector (illustrated) for converting white light emitted from the light bulb as divergent light into parallel light. And. As a result, the lamp 33 emits white light as parallel light along the optical axis of the condenser lens 28 through the dichroic mirror 29 toward the condenser lens 28.

  The diaphragm 32 is disposed completely in parallel with the optical axis of the condensing lens 28 outside the optical path of white light, and is completely optical path of white light by the second motor 41 supplied with a drive current by the second motor drive control circuit 30. It is rotatably held between a position retracted to the outside and a position inserted in the optical path of white light leaving only a gap through which a minimum amount of light passes. The second motor drive control circuit 30 receives the luminance value from the pre-stage signal processing circuit 26 described later, and the second motor 42 moves the diaphragm 32 to an arbitrary rotational position so that the luminance value falls within a predetermined range. Auto dimming to rotate.

  The rotary shutter 27 is a disc in which a fan-shaped (1/2 annular) opening having a central angle of 180 degrees is formed, and is orthogonal to the optical axis of the condenser lens 28 and offset. The first motor drive control circuit 37 is fixed to the tip of the rotating shaft of the first motor 34 to which the drive current is supplied.

  The dichroic mirror 29 is disposed with an inclination of 45 degrees with respect to the optical axis of the condenser lens 28. Therefore, the dichroic mirror 29 reflects only light in a specific wavelength band used as excitation light and transmits light in other bands. Then, on the optical path of the light reflected by the dichroic mirror 29 and incident on the condensing lens 28 (that is, the optical axis of the condensing lens 28 bent by 90 degrees by the dichroic mirror 29), the dichroic mirror 29 side sequentially. In addition, an open / close shutter 39 and an excitation light source 23 are arranged. The dichroic mirror 29 and the condenser lens 28 correspond to an optical system that guides the excitation light to the base end of the light guide inserted into the socket.

  The excitation light source 23 incorporates a semiconductor laser that emits laser light in a wavelength band that functions as excitation light, and a collimator lens that corrects the excitation light emitted as diverging light into parallel light.

  The open / close shutter 39 is located at the center of the solenoid 22 in a plane orthogonal to the paper surface of FIG. 2 by the solenoid 22 to which a drive current is supplied by the shutter drive circuit 21 (ie, disposed outside the optical path of the excitation light). It is supported by a rotating shaft (not shown), and is rotated by the solenoid 22 so that it can be inserted into and removed from the optical path of the excitation light from above. The opening / closing shutter 39 has an area that can completely close the optical path of the excitation light at any rotational position, and the opening / closing shutter 39 rotates further downward than the position at which the optical path of the excitation light is completely closed. A stopper (not shown) that prevents this is provided below the optical path of the excitation light. Further, a stopper (not shown) that prevents the opening / closing shutter 39 from rotating further upward than the position completely retracted from the optical path of the excitation light is provided above the optical path of the excitation light. Therefore, unless the drive current is supplied to the solenoid 22 by the shutter drive circuit 21, the open / close shutter 39 rotates downward due to its own weight and is held at a position where the optical path of the excitation light is completely closed.

  The front panel of the housing of the light source processor device 20 has an electrical socket composed of a number of electrodes each conducting with each connector pin constituting an electrical connector (not shown) when the light guide 16 is inserted into the socket 20a. (Not shown) is provided. Of the electrodes constituting the electrical socket (not shown), the one that conducts to the shutter closing signal cable 41 is connected to the shutter drive circuit 21.

  Accordingly, if the sub-controller 40 outputs a shutter open signal while an electrical connector (not shown) is connected to an electrical socket (not shown), this shutter open signal is input to the shutter drive circuit 21. The shutter drive circuit 21 supplies a drive current to the solenoid 22 only while the shutter open signal is input. The solenoid 22 that has received the drive current in this way applies an external force to the open / close shutter 39 and rotates it upward. As a result, as long as the drive current is supplied to the solenoid 22, the open / close shutter 39 is maintained at a position completely retracted from the optical path of the excitation light by contacting a stopper (not shown).

  With the optical configuration described above, the white light emitted from the lamp 33 is partially stopped by the stop 32 and passes through the rotary shutter 27 only during a period in which the opening of the rotary shutter 27 is positioned on the optical axis of the condenser lens 28. Further, the light passes through the dichroic mirror 29 and the condenser lens 28. On the other hand, the excitation light emitted from the excitation light source 23 only while the drive current is supplied from the excitation light source is blocked by the opening / closing shutter 39 when the opening / closing shutter 39 is closed. When the shutter 39 is open, it is reflected by the dichroic mirror 29 and passes through the condenser lens 28. The white light and the excitation light incident on the condensing lens in this manner are collected by the condensing lens 28, are incident on the base end surface of the light guide 16, are guided by the light guide 16, and are distributed. The light is diverged through the optical lens 11.

  Next, each element constituting the image processing unit 20b will be described.

  Among the electrodes constituting the above-described electrical socket (not shown), the one that conducts to the drive signal cable 19 is connected to the image sensor control drive circuit 35. Similarly, what is conducted to the image signal cable 18 b is connected to the previous signal processing circuit 26. Similarly, what is conducted to the operation signal cable 17 b is connected to the main controller 24. Further, an operation panel 23 having a plurality of switches operated from the outside is provided on the front panel of the housing of the light source processor device 20, and these switches also input signals indicating on / off thereof. In order to do so, it is connected to the main controller 24.

  The main controller 24 is further connected to the lamp power supply circuit 38, the excitation light source drive control circuit 43 that supplies a drive current to the excitation light source 23, the timing controller 25, and the subsequent signal processing circuit 36. The timing controller 25 is further connected to the first motor drive control circuit 37, the excitation light source drive control circuit 43, the image sensor control drive circuit 35, the RGB memory 31, and the subsequent signal processing circuit 36 described above.

  Under the control of the main controller 24, the timing controller 25 generates a timing signal in each frame period (1/30 second), and sends it to each circuit 31, 35, 36, 37, 43 connected to itself. On the other hand, it supplies selectively. While receiving the timing signal, the first motor drive control circuit 37 synchronizes with the timing signal so that the rotary shutter 27 rotates at a cycle of 1 frame (1/30 second). When a timing signal is stopped, the rotary shutter 27 is stopped at a rotational position where an opening (not shown) overlaps the optical path of white light. The image sensor control drive circuit 35 generates a control signal including a vertical synchronization signal and a horizontal synchronization signal in synchronization with the timing signal, and supplies the control signal to the image sensor 13. Further, the excitation light source drive control circuit 43 outputs white light emitted from the lamp 33 in synchronization with the timing signal from the timing controller 25 while the main controller 24 instructs to emit excitation light. The drive current is supplied so that the excitation light is emitted from the excitation light source 23 only during the period when is blocked by the rotary shutter 27.

  When the proximal end of the light guide 16 of any endoscope is inserted into the socket 20a and an electrical connector (not shown) is connected to an electrical socket (not shown), the main controller 24 is connected to the endoscope. By detecting a change in the electrical state (impedance, potential, etc.) of the terminal, it is detected that the endoscope is connected. In this way, when the ON signal of the white light lighting switch on the switch panel 23 is input while detecting that the endoscope is connected, the main controller 24 first performs normal observation. Operating in the mode, instructing the post-stage signal processing circuit 36 to perform processing according to the normal observation mode, and controlling the timing controller 25 to control the image sensor control drive circuit 35, the RGB memory 31, and the post-stage signal The timing signal is output to the processing circuit 36, and the lamp power supply circuit 38 is controlled to emit white light from the lamp 33. Then, the white light emitted from the lamp 33 passes through the opening of the rotary shutter 27 stopped as described above, enters the base end surface of the light guide 16, and is irradiated through the light distribution lens 11. . At this time, when the body cavity insertion portion 10a of the endoscope is inserted into the body cavity of the subject, white light reflected from the surface of the body cavity inner wall is reflected on the image of the body cavity inner wall via the objective lens 12. Are formed on the imaging surface of the imaging device 13. Since the image pickup device 13 is supplied with a control signal from the image pickup device control drive circuit 35, the image pickup device 13 picks up this image and converts it into an image signal. This image signal is processed by the sub-controller 40 and then input to the pre-stage signal processing circuit 26. As a result, as shown in the timing chart of FIG. 3 (a), the first signal processing circuit 26 receives images (visible images) of the reflected light from the inner wall of the body cavity in the first and second fields. The image signal shown is input.

  Furthermore, when the endoscope whose electrical connector is connected to an electrical socket (not shown) is the fluorescence observation endoscope 10 according to the present embodiment, it is incorporated in the fluorescence observation endoscope 10. By communicating with the sub-controller 40 and receiving identification information indicating the attribute, it is possible to know that the endoscope is the fluorescence observation endoscope 10. At this time, when receiving a code signal indicating that the button 10e corresponding to the observation mode switch has been pressed from the sub-controller 40, the main controller 24 switches the operation to the fluorescence observation mode, and causes the rear-stage signal processing circuit 36 to perform fluorescence. An instruction is given to perform processing according to the observation mode, and an instruction is given to the excitation light source drive control signal 43 that excitation light should be emitted. Then, as described above, the excitation light source 23 emits excitation light only during a period in which white light is blocked by the rotary shutter 27. At this time, if a shutter open signal is input from the sub-controller 40 to the shutter drive circuit 21, the open / close shutter 30 is completely retracted from the optical path of the excitation light, so that the excitation light is as described above. , Is incident on the base end face of the light guide 16, and is irradiated through the light distribution lens 11. That is, white light is emitted from the light distribution lens 11 in the first half (period corresponding to the first field) in one frame period (1/30 seconds), and in the second half (period corresponding to the second field). Is ejected. Then, in a situation where the endoscope body cavity insertion portion 10a is inserted into the body cavity of the subject, when excitation light is irradiated from the light distribution lens 11 to the body cavity inner wall, the living tissue under the body cavity inner wall is It is excited by excitation light and emits fluorescence. Part of this fluorescence enters the objective lens 12 and forms an image on the imaging surface of the imaging device 13. The image pickup device 13 converts the fluorescent image into an image signal. This image signal is processed by the sub-controller 40 and then input to the pre-stage signal processing circuit 26. As a result, as shown in the timing chart of FIG. 3 (b), the first field shows an image (visible image) made up of the reflected light from the inner wall of the body cavity with the second field. A series of image signals indicating an image (fluorescence image) in which the field is composed of fluorescence from the inner wall of the body cavity are input.

  Thereafter, each time the main controller 24 receives a code signal indicating that the button 10e corresponding to the observation mode switching has been pressed from the sub-controller 40 of the fluorescence observation endoscope 10, the operation is changed to the normal observation mode and the fluorescence. Switch between observation modes.

  The pre-stage signal processing circuit 26 performs processing such as color space conversion, color balance, and image quality correction on the image signal received from the sub-controller 40 of the fluorescence observation endoscope 10, and then performs RGB memory for each color. Write to 31. At the same time, the pre-stage signal processing circuit 26 calculates an average value of luminance indicated by the image signal for each frame, inputs the average luminance value to the second motor drive control circuit 30 described above, and performs the automatic adjustment described above. Let the light do.

  The RGB memory 31 primarily stores the image signal processed by the pre-stage signal processing circuit 26 for each color and for each field of each frame.

  The post-stage signal processing circuit 36 reads out image signals of each color in units of frames from the RGB memory 31 and converts them into video signals of the NTSC system or the like when instructed by the main controller 24 in accordance with the normal observation mode. The video signal (hereinafter referred to as “normal observation signal” for convenience) is output to the monitor 60. On the other hand, when the processing according to the fluorescence observation mode is instructed from the main controller 24, the post-stage signal processing circuit 36 receives an image signal (that is, a visible image) constituting the first field in units of frames from the RGB memory 31. Image signal) and the image signal constituting the second field (that is, the image signal indicating the fluorescence image) are read out, the luminance ratio between the former and latter pixels is calculated, and the luminance ratio is equal to or greater than a predetermined value. Is identified as a lesion, and a signal indicating the range of the lesion in a specific color is imposed on the image signal constituting the first field, and then converted into a video signal of the same format as described above. A signal (for convenience, hereinafter referred to as “fluorescence observation signal”) is output to the monitor 60.

  While the main controller 24 is operating in the normal observation mode, a moving image (that is, a visible image in the body cavity) based on the normal observation signal is displayed on the monitor 60, and the main controller 24 is in the fluorescence observation mode. During the operation, a moving image based on the fluorescence observation signal (that is, a fluorescent image in the body cavity) is displayed.

  As described above, the main controller 24 of the light source processor device 20 and the sub-controller 40 of the fluorescence observation endoscope 10 communicate with each other, and when one transmits a command to the other, the other Polling that returns a response signal (Ack response) is always performed.

  However, if lighting noise or disturbance noise of the lamp 33 occurs in the light source processor device 20, the main controller 24 may malfunction. If a malfunction occurs in this way, the main controller 24 cannot return an ack response to the command from the sub-controller 40, and further has a problem that the excitation light source 23 continuously emits excitation light. Can occur.

  The sub controller 40 that periodically polls the main controller 24 for the command detects that the ack response to the command transmitted to the main controller 24 is not returned, thereby confirming that the main controller 24 is malfunctioning. Can be recognized. In this way, when recognizing that the main controller 24 malfunctions, the sub-controller 40 stops outputting the shutter open signal. If the sub controller 40 is incorporated in the light source processor device 20, if the main controller 24 malfunctions due to noise, the sub controller 40 also malfunctions at the same time, causing the main controller 24 to malfunction. There is a possibility that the shutter open signal may continue to be output without detecting the occurrence of the shutter. However, the influence of such noise does not reach the sub-controller 40 located outside the light source processor device 20. Therefore, even if the main controller 40 that controls the lighting of the excitation light source 23 malfunctions, the sub-controller 40 can continue to operate normally, so that the shutter open signal can be stopped reliably.

  When the shutter open signal is stopped in this way, as described above, the shutter drive circuit 21 stops the supply of drive current to the solenoid 22, so that the open / close shutter 39 is driven by the excitation light source 23 due to its own weight. Close the optical path of the excitation light from. As a result, the excitation light is prevented from proceeding from the opening / closing shutter 39, so that the light guide 16 of the endoscope (fluorescence observation endoscope 10) is excited from the socket 20a when not inserted into the socket 20a. When the light guide 16 of the endoscope (fluorescence observation endoscope 10) is inserted into the socket 20a, there is no risk of causing damage to the outer skin or eyeball of the patient or the operator due to light leakage. Due to the continuous emission of the excitation light from the light distribution lens 11 of the endoscope (fluorescence observation endoscope 10), there is no possibility of causing burns or canceration on the inner wall of the body cavity of the subject.

1 is an external view showing the external appearance of a fluorescence endoscope system according to an embodiment of the present invention. Schematic diagram showing the internal configuration of the fluorescence endoscope system Timing chart showing the timing of the image signal input to the pre-stage signal processing circuit 26

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Fluorescence observation endoscope 11 Light distribution lens 12 Objective lens 13 Image pick-up element 16 Light guide 17 ROM
21 Shutter drive circuit 22 Solenoid 23 Excitation light source
24 Main controller 39 Opening / closing shutter 40 Sub controller 43 Excitation light source drive control circuit

Claims (3)

An endoscope having a long body cavity insertion portion that is inserted into the body cavity and the light guide is passed through the entire length of the body cavity, and the light guide of the endoscope is excited to fluoresce the living tissue. A fluorescence endoscope system including a light source device that supplies excitation light that generates
The light source device is
A socket into which the proximal end of the light guide is inserted;
An excitation light source that emits the excitation light;
A shutter mechanism that opens the optical path of the excitation light only while a shutter open signal is input;
An optical system that guides the excitation light that has passed through the shutter mechanism to the proximal end of the light guide inserted into the socket;
A main controller for controlling the excitation light source;
The endoscope is
An objective optical system for linking an image by fluorescence from a living tissue irradiated through the light guide;
An image sensor that captures the image connected by the objective optical system;
As long as it is connected to the main controller, periodically communicates with the main controller, and receives a response from the main controller, it outputs the shutter open signal to the shutter mechanism. And a sub-controller that stops the output of the shutter opening signal to the shutter mechanism when the response is not received. The endoscope is
While the base end of the light guide protrudes and is fixed to the end face, and has a connector portion provided with an electrical connector connected to the sub-controller,
The light source device includes an electrical socket connected to the electrical connector and connected to the main controller and the shutter mechanism, respectively, when a proximal end of the light guide is inserted into the socket. Item 2. The fluorescence endoscope system according to Item 1. The shutter mechanism is
While being rotatable around a rotation axis arranged outside the optical path of the excitation light, in a state where no external force is applied, due to its own weight, the optical path of the excitation light is moved to a position to be closed, and an external force is applied, An open / close shutter that moves to a position that opens the optical path of the excitation light;
A solenoid that applies an external force to move the opening / closing shutter to a position that opens an optical path of the excitation light when a driving current is supplied;
2. The fluorescence endoscope system according to claim 1, further comprising a drive circuit that supplies a drive current to the solenoid only while the shutter opening signal is input.