JP2005143723A - Endoscope system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an endoscope system which can select a wavelength band of exciting light, further, prevent the exciting light as stray light from being mixed into fluorescent light incident into a photographing unit no matter which wavelength band is selected, in generating a normal image and a special image based on a fluorescent light image by shooting out illumination light and the exciting light from the distal end of an endoscope. <P>SOLUTION: An exciting light eliminating filter 182 for eliminating the light having the same wavelength band as that of the exciting light is assembled and further, a short-circuiting portion 184 for short-circuiting a pair of three electrode plates 191 to 193 in the distal end of the inserting portion 10a is provided in a cap 18 removably mounted on the distal end of an inserting portion 10a of an electronic endoscope 10. A distal end detecting portion 23 identifies the cap 18 based on the pair of short-circuited electrode plates, and controls a first and a second light source portions 25, 31 such that the exciting light having the same wavelength band as that of the light eliminated with exciting light eliminating filter of the cap 18 is introduced into a light guide 15. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an endoscope system for observing the inside of a body cavity such as the gastrointestinal tract and bronchi.

  As is well known, biological tissue is excited to emit 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 the endoscope systems, illumination light for illuminating the inside of a body cavity into which the distal end of the endoscope is inserted and excitation light for exciting living tissue under the body cavity wall are supplied to the endoscope. An endoscope system capable of alternately emitting illumination light and excitation light from the distal end of the endoscope is disclosed in Patent Document 1.

  In the endoscope system described in Patent Document 1, an excitation light transmission filter for extracting excitation light from the white light with respect to an optical path of white light introduced into a light guide in the endoscope is provided with a predetermined filter. It is configured to insert repeatedly with a time interval. For this reason, white light and excitation light as illumination light are alternately introduced into the light guide in the endoscope.

  In addition, the endoscope system described in Patent Document 1 is formed by an image in a body cavity (normal image) formed by illumination light reflected from the surface of the body cavity wall and fluorescence emitted from a living tissue under the body cavity wall. The images inside the body cavity (fluorescence image) are alternately obtained through the imaging device, and special images generated based on the normal image and the fluorescence image are sequentially displayed on the monitor.

Furthermore, in the endoscope system described in Patent Document 1, when excitation light is irradiated into a body cavity, a fluorescence image is generated in a state where the excitation light reflected from the surface of the body cavity wall is mixed with fluorescence as stray light. In order to prevent this, an excitation light removal filter for removing excitation light is assembled between the objective optical system and the imaging apparatus.
JP 06-125911 A (0024-0027, FIG. 1)

  By the way, recent research has revealed that the difference in the wavelength band of excitation light causes some kind of change in the reaction phenomenon of living tissue. For this reason, it is expected that a researcher will make a request to observe a special image while changing the wavelength band of the excitation light.

  However, the endoscope system described in Patent Document 1 described above has only one excitation light transmission filter for transmitting excitation light of one wavelength band. However, the excitation light removal filter assembled between the objective optical system and the imaging apparatus also supports only one wavelength band. For this reason, the conventional endoscope system has a problem that the wavelength band of the excitation light cannot be changed.

  Therefore, an object of the present invention is to select a wavelength band of excitation light when generating a special image based on a normal image and a fluorescence image by emitting illumination light and excitation light from the distal end of the endoscope. In addition, it is an object of the present invention to provide an endoscope system that can prevent excitation light as stray light from being mixed with fluorescence incident on an imaging apparatus regardless of which wavelength band is selected.

  An endoscope system invented to solve the above-described problems is configured as described below.

  That is, this endoscope system includes a thin tubular insertion portion for insertion into a body cavity, and illumination optics that guides light from the proximal end to the distal end of the insertion portion and emits the guided light from the distal end of the insertion portion. System, an objective optical system that forms an image in the body cavity when the distal end of the insertion portion is inserted into the body cavity, and an imaging device that captures the image formed by the objective optical system and generates image data An excitation light removal filter that removes excitation light in a specific wavelength band that excites biological tissue under the body cavity wall, and an identification unit that holds information corresponding to the specific wavelength band, and A cap that is detachably attached to the distal end of the insertion portion in a state where the excitation light removal filter is positioned in front of the objective optical system, and one wavelength band selected from a plurality of wavelength bands of excitation light Excitation light to the illumination Based on the information held by the identification unit provided in the cap, the wavelength band of the excitation light removed by the excitation light removal filter provided in the cap attached to the distal end of the insertion part and the light source part introduced into the academic system It is characterized by comprising a light source device comprising a detection unit for detection and a light source control unit for causing the light source unit to select excitation light in the wavelength band detected by the detection unit.

  When configured in this way, when any cap is attached to the distal end of the insertion portion of the endoscope, the wavelength band of the excitation light that the detection unit of the light source device removes by the excitation light removal filter included in the cap The light source control unit causes the light source unit to introduce excitation light having the same wavelength band as the wavelength band into the illumination optical system. Then, the excitation light in that wavelength band is emitted from the tip of the insertion portion inserted into the body cavity, and is one of the light including the excitation light reflected by the surface of the body cavity wall and the fluorescence emitted by the biological tissue under the body cavity wall. The part goes to the objective optical system. At this time, the light incident on the objective optical system is always removed of the component in the wavelength band by the excitation light removing filter of the cap attached to the tip of the insertion portion. Therefore, fluorescence, which is light in the remaining wavelength band, enters the imaging device of the endoscope. That is, the fluorescence incident on the imaging apparatus does not include the excitation light reflected by the surface of the body cavity wall as stray light, so that a fluorescence image is not generated in a state where the stray light is mixed with the fluorescence.

  Therefore, the operator of the endoscope system selects an arbitrary cap from the plurality of caps, and simply attaches the selected cap to the distal end of the insertion portion of the endoscope. The wavelength band of the excitation light emitted from the light source unit can be changed. However, since a removal filter for removing the excitation light is always arranged in front of the objective optical system in the insertion portion of the endoscope, it enters the photographing apparatus through the objective optical system of the endoscope. The excitation light as stray light is not mixed with the fluorescent light.

  As described above, according to the present invention, when a special image based on a normal image and a fluorescence image is generated by emitting illumination light and excitation light from the distal end of an endoscope, The wavelength band can be selected, and even if any wavelength band is selected, the excitation light as stray light is prevented from being mixed with the fluorescence incident on the imaging apparatus.

  Hereinafter, two embodiments for carrying out the present invention will be described with reference to the drawings.

Embodiment 1

  FIG. 1 is an external view of an electronic endoscope system according to the first embodiment of the present invention. As shown in FIG. 1, the electronic endoscope system includes an electronic endoscope 10, a light source processor device 20, a special light source device 30, and a monitor 40.

  FIG. 2 is a configuration diagram schematically showing the inside of the electronic endoscope 10 and the light source processor device 20. Although the detailed shape of the electronic endoscope 10 is not shown in FIG. 2, the electronic endoscope 10 includes a flexible thin tubular insertion portion 10a for insertion into a body cavity. A bending portion is incorporated at the distal end of the insertion portion 10a, and an operation portion 10b is provided at the base end thereof. The operation portion 10b is provided for operating the bending amount and the bending direction of the bending portion. An angle knob and various switches are provided.

  In addition, three through holes (see FIG. 3) are formed in the distal end surface of the insertion portion 10a, and the light distribution lens 11 and the objective lens 12 are fitted into the pair of through holes, respectively.

  The remaining one through hole is used as the forceps port 13. A thin tube 14 that connects the forceps port 13 and the forceps port formed in the operation unit 10b is drawn through the insertion unit 10a. The thin tube 14 functions as a forceps channel for inserting a treatment tool such as a forceps, a scissors, or a coagulation electrode.

  Further, the light guide 15 is passed through the insertion portion 10a. The light guide 15 is composed of a large number of flexible optical fibers, and the tip surface thereof faces the light distribution lens 11. The proximal end of the light guide 15 is led through a flexible tube 10c extending from the side surface of the operation unit 10b. Further, the proximal end of the light guide 15 is connected to the distal end of a connector unit 10d provided at the distal end of the flexible tube 10c. It has been fixed.

  Furthermore, the image sensor 16 is incorporated in the insertion portion 10a. The imaging device 16 is a single-plate area image sensor having an imaging surface composed of a number of pixels arranged two-dimensionally, and a primary color filter is on-chip on the imaging surface. The imaging element 16 is arranged on the optical axis in a state perpendicular to the optical axis of the objective lens 12, and the position of the imaging surface substantially coincides with the position of the image plane of the objective lens 12. Yes.

  At least two signal lines 16 a and 16 b are connected to the image sensor 16. One signal line 16a is an electric wire for transmitting a drive signal for the image pickup device 16, and the other signal line 16b is an electric wire for transmitting an image signal output from the image pickup device 16.

  These signal lines 16a and 16b are sequentially passed through the insertion portion 10a and the flexible tube 10c. One signal line 16a is connected to the driver 17 in the connector portion 10d, and the other signal line 16b is , And is fixed to the tip of the connector portion 10d. The driver 17 is a circuit for generating a drive signal for the image sensor 16 and outputting it to the image sensor 16.

  Further, although not shown in FIGS. 1 and 2, a cap 18 can be attached to the distal end of the insertion portion 10a. As will be described later, the cap 18 includes an optical filter having predetermined optical characteristics, and is detachable from the distal end of the insertion portion 10a. In the first embodiment, three caps 18, 18 ′, 18 ″ having different optical characteristics of the optical filter are prepared, but all are formed in the same shape. The shape and mounting structure of one cap 18 will be described without distinguishing between 18, 18 ′, and 18 ″, and then the difference in optical characteristics of the optical filters of the caps 18, 18 ′, 18 ″ will be described. To do.

  FIG. 3 is a perspective view for explaining the shape and mounting structure of the cap 18. 4 is a rear view of the cap 18, and FIG. 5 is a cross-sectional side view of the cap 18 cut along the line AA in FIG. 6 is an explanatory diagram for explaining a method of attaching the cap 18 to the distal end of the insertion portion 10a.

  The insertion portion 10a of the electronic endoscope 10 is formed in a cylindrical shape. However, as shown in FIG. 3, the portion 10e having a predetermined width from the distal end of the insertion portion 10a toward the operation portion 10b is formed so that the outer diameter is slightly smaller than the other portions. Hereinafter, the portion 10e having a thin outer diameter is referred to as a “small-diameter protrusion”.

  As shown in FIG. 3, the small-diameter protruding portion 10e is formed in a D-cut shape, and the circumferential direction of the outer peripheral surface other than the flat portion (cut surface in the D-cut shape) 10p is the circumferential direction. A key groove 10k having a semicircular cross section is formed along the line. Note that the opening of the through hole into which the light distribution lens 11 is fitted, the opening of the through hole into which the objective lens 12 is fitted, and the forceps port 13 are formed on the distal end surface of the small-diameter protruding portion 10e.

  Moreover, the electrode part 19 is provided in the flat surface 10p of the small diameter protrusion part 10e. The electrode portion 19 is composed of three strip-shaped electrode plates having high acid resistance and conductivity. As shown in FIG. 6, the three electrode plates 191 to 193 have their longitudinal directions oriented in the axial direction of the insertion portion 10a, and are spaced at equal intervals in the direction perpendicular to the axial direction. In a state where they are arranged in parallel, they are adhered to the vicinity of the end on the objective lens 12 side on the flat surface 10p.

  Three electric wires 19a to 19c are connected to the three electrode plates 191 to 193, respectively. As shown in FIG. 2, these three electric wires 19a to 19c are sequentially passed through the insertion portion 10a and the flexible tube 10c, and their tips are all connected to the tip of the connector portion 10d. It is fixed.

  The cap 18 is formed in a flat bottomed substantially cylindrical shape with respect to the small-diameter protruding portion 10e, and has an outer diameter substantially the same as the outer diameter of the insertion portion 10a. However, the inner peripheral surface of the cap 18 is not cylindrical, but is formed in a D-cut shape as shown in FIG. Further, as shown in FIG. 5, a single semicircular cross section is provided along the circumferential direction except for a flat portion (cut surface in the D-cut shape) 18 p of the inner peripheral surface of the cap 18. A key 18k is formed to protrude. The cap 18 body is made of a material such as a resin that can be slightly deformed by an external force.

  As shown in FIG. 4, three through holes are formed in the bottom of the cap 18, and optical filters 181 and 182 are fitted in a pair of through holes. One optical filter 181 is a full-wavelength component transmission filter that transmits light in a wavelength band of about 350 nm to 700 nm. The other optical filter 182 is an excitation light removal filter that removes only light in the same wavelength band as the excitation light for exciting the living tissue under the body cavity wall and transmits light in other wavelength bands. Nothing is fitted in the remaining one through hole 183.

  Further, the flat surface 18 p of the cap 18 is provided with a short-circuit portion 184. The short-circuit portion 184 is a metal plate having high acid resistance and high conductivity, and is bonded to the vicinity of the end portion on the excitation light removal filter 182 side on the flat surface 18p, as shown in FIG.

  Since the distal end of the insertion portion 10a and the cap 18 are configured as described above, the flat surface 10p of the small-diameter protruding portion 10e and the flat surface 18p of the cap 18 are brought into contact with each other as shown in FIG. If the diameter protrusion 10e is fitted inside the cap 18 and the small diameter protrusion 10e is pushed further into the cap 18, the key 18k of the cap 18 is fitted into the key groove 10k of the small diameter protrusion 10e. By mounting in this manner, the cap 18 is firmly fixed to the distal end of the insertion portion 10a.

  On the contrary, if the cap 18 is pulled out from the distal end of the insertion portion 10a with such a strength that the key 18k of the cap 18 is removed from the key groove 10k of the small diameter protruding portion 10e, the cap 18 is removed from the distal end of the insertion portion 10a. It is.

  When the cap 18 is attached to the distal end of the insertion portion 10a, the all-wavelength component transmission filter 181 is located in front of the light distribution lens 11, the excitation light removal filter 182 is located in front of the objective lens 12, and forceps A through hole 183 is located in front of the mouth 13. At this time, when the insertion portion 10a is viewed from the front, the all-wavelength component transmission filter 181 overlaps with the light distribution lens 11, the excitation light removal filter 182 overlaps with the objective lens 12, and the through hole 183 overlaps with the forceps port 13. .

  At this time, since both the inner peripheral surface of the cap 18 and the outer peripheral surface of the small-diameter protruding portion 10e are D-cut, the cap 18 is thin when the cap 18 is fixed to the small-diameter protruding portion 10e. It cannot be rotated with respect to the radial protrusion 10e. Accordingly, when the insertion portion 10a is viewed from the front, the all-wavelength component transmission filter 181 is present at a position shifted from the light distribution lens 11, or the excitation light removal filter 182 is present at a position shifted from the objective lens 12. And the through hole 183 does not exist at a position shifted from the forceps port 13.

  Since the distal end portion of the insertion portion 10a and the cap 18 are configured as described above, the light that has passed through the light distribution lens 11 always passes through the all-wavelength component transmission filter 181 and the objective lens 12 The light that is about to enter the light necessarily passes through the excitation light removal filter 182.

  As shown in FIGS. 4 and 5, on the inner surface of the bottom of the cap 18, a cylindrical protrusion 18 c is integrated with the cap 18 at the edge of the through-hole into which the all-wavelength component transmission filter 181 is fitted. Is formed. When the small-diameter protruding portion 10e is pushed to the back of the cap 18, the distal end surface of the protruding portion 18c comes into contact with the distal end surface of the small-diameter protruding portion 10e, and the protruding portion 18c becomes the all-wavelength component transmission filter 181. And the space between the light distribution lens 11 is sealed. This prevents light emitted from the light distribution lens 11 from entering between the excitation light removal filter 182 and the objective lens 12.

  When the cap 18 is attached to the distal end of the insertion portion 10a, any two of the three electrode plates 191 to 193 on the flat surface 10p of the small-diameter protruding portion 10e are short-circuited by the short-circuit portion 184. Is done. The shape of the short-circuit portion 184 and the arrangement position on the flat surface 18p are different in each of the three caps 18, 18 ′, 18 ″. FIG. 7 is an explanatory diagram for describing the forms of the short-circuit portions 184, 184 ′, 184 ″ of the three caps 18, 18 ′, 18 ″, respectively.

  As shown in FIG. 7, the short-circuit portion 184 bonded to the flat surface 18p of the first cap 18 is formed in a rectangular shape, and when the first cap 18 is attached to the distal end of the insertion portion 10a. Short-circuits the first electrode plate 191 and the second electrode plate 192. In order to explain the short-circuit state at this time, the three electrode plates 191 to 193 are shown by broken lines in the sectional side view of FIG.

  Further, the short-circuit portion 184 ′ bonded to the flat surface 18p of the second cap 18 ′ is formed in a U-shape, and when the second cap 18 ′ is attached to the tip of the insertion portion 10a, The first electrode plate 191 and the third electrode plate 193 are short-circuited.

  Further, the short-circuit portion 184 ″ adhered to the flat surface 18p of the third cap 18 ″ is formed in a rectangular shape, and when the third cap 18 ″ is attached to the distal end of the insertion portion 10a, the short-circuit portion 184 ″ is formed. The two-electrode plate 192 and the third electrode plate 193 are short-circuited.

  All the wavelength component transmission filters 181 included in the three caps 18, 18 ′, and 18 ″ described above have the same optical characteristics (transmission of light in a wavelength band of about 350 nm to 700 nm). On the other hand, the excitation light removal filters 182 of the caps 18, 18 ', 18 "have different optical characteristics.

  The excitation light removal filter 182 of the first cap 18 is an optical filter that removes light in the first wavelength band of about 400 nm to 450 nm, and the excitation light removal filter 182 ′ of the second cap 18 ′ is about 350 nm to 380 nm. The third excitation light removal filter 182 ′ of the third cap 18 ″ is an optical filter that removes light in the third wavelength band of about 400 nm to 430 nm.

  As described above, the three caps 18, 18 ′, 18 ″ are all formed in the same shape, but when three caps having the same shape are prepared in this way, the operator There is a possibility that the optical characteristics of the excitation light removal filter 182 cannot be distinguished from the appearance of the cap. Therefore, as shown in FIG. 3, the side surfaces of the three caps 18, 18 ′, 18 ″ are individually identified. Identification information for each is described.

  As illustrated in FIG. 2, the light source processor device 20 includes a timing control unit 21, a system control unit 22, a tip detection unit 23, an image processing unit 24, and a first light source unit 25.

  Note that a connector receiver into which the connector portion 10d can be fitted is provided on a side surface of the housing of the light source processor device 20. When the connector portion 10d is fitted into the connector receptacle, the driver 17 in the connector portion 10d is connected to the timing control portion 21 via a signal line (not shown), and various switches on the operation portion 10b of the electronic endoscope 10 are operated. It is connected to the system control unit 22 via a signal line (not shown), the three electric wires 19a to 19c are connected to the tip detection unit 23, the signal line 16b is connected to the image processing unit 24, and the base end of the light guide 15 Enters the first light source unit 25.

  The timing control unit 21 is a controller that generates various reference signals and controls the output of the signals. Various processes in the light source processor device 20 and the driver 17 in the connector unit 10d proceed according to this reference signal.

  In the light source processor device 20, one cycle (for example, 1/30 second) is defined by a set of two timings indicated by the reference signal, and the second timing from the first timing in the cycle is the second. The units 22, 24, and 25 proceed with processing with the period between the timings as the first field period and the period from the second timing to the first timing in one cycle as the second field period.

  The system control unit 22 is a controller that controls the entire light source processor device 20. The system control unit 22 is connected to various switches provided on the operation unit 10b of the electronic endoscope 10 and switches on an operation panel (not shown). When an input is received through these switches, Perform processing according to the input.

  Further, the system control unit 22 switches the operation mode to either the normal observation mode or the tip detection mode in accordance with the switching operation performed on the switch SW on the operation unit 10b of the electronic endoscope 10. Furthermore, when the system control unit 22 receives a notification from the tip detection unit 23 (described later) in the tip detection mode, the system control unit 22 selects any one of the first to third special observation modes determined based on the notification from the tip detection mode. Switch the operation mode to one special observation mode.

  The tip detection unit 23 detects which of the first to third caps 18, 18 ′, 18 ″ is the cap attached to the tip of the insertion portion 10a of the electronic endoscope 10 in the tip detection mode. Circuit.

  More specifically, when notified from the system control unit 22 that the tip detection unit 23 has been switched to the tip detection mode, the tip detection unit 23 passes through the three electric wires 19a to 19c in the electrode unit 19 at the tip of the insertion unit 10a. A process of applying different voltages to each of the electrode plates 191 to 193 is started, and the process waits until any one of the first to third caps 18, 18 ′, 18 ″ is attached to the distal end of the insertion portion 10a. .

  And, when any cap is attached to the tip of the insertion portion 10a, the potential of the pair of electrode plates changes by short-circuiting any pair of electrode plates by the short-circuit portion 184 of the cap. The tip detection unit 23 specifies a pair of shorted electrode plates by detecting the potential of each electrode plate, and notifies the system control unit 22 of information indicating the specified pair of electrode plates.

  Upon receiving this notification, the system control unit 22 instructs the tip detection unit 23 to stop applying the voltage to the three electrode plates 191 to 193, and the tip detection unit 23 receives this instruction. Then, the process of applying a voltage to the three electrode plates 191 to 193 is stopped.

  The system control unit 22 changes the operation mode when the tip detection unit 23 is notified of information indicating that the pair of shorted electrode plates is the first electrode plate 191 and the second electrode plate 192. 1 Switch to the special observation mode. Further, when the tip detection unit 23 notifies the system control unit 22 of information indicating that the pair of shorted electrode plates is the first electrode plate 191 and the third electrode plate 193, the system control unit 22 sets the operation mode. When the tip detection unit 23 notifies that the pair of short-circuited electrode plates are the second electrode plate 192 and the third electrode plate 193, the operation mode is changed to the third special observation mode. Switch to.

  The image processing unit 24 is a unit for performing various processes on the image signal sent from the image sensor 16. FIG. 8 is a configuration diagram schematically showing the inside of the image processing unit 24.

  As shown in FIG. 8, the image processing unit 24 includes a first-stage processing circuit 241, a red component memory 242r, a green component memory 242g, a blue component memory 242b, a luminance component generation circuit 243, and a first luminance component memory 244a. , A second luminance component memory 244b, an affected part image data generation circuit 245, a switch circuit 246, an adder 247, and a post-stage processing circuit 248.

  The first stage processing circuit 241 is a circuit for constantly receiving an image signal sent from the image sensor 16 and performing a predetermined process on the image signal. The processing performed on the image signal by the first stage processing circuit 241 includes high-frequency component removal, amplification, blanking, clamping, white balance, gamma correction, analog-digital conversion, and color separation. The first-stage processing circuit 241 generates image data of each color component of red (R), green (G), and blue (B) by performing the above-described processing on the image signal.

  The first-stage processing circuit 241 outputs the image data of each color component generated in the first field period to each color component memory 242r, 242g, 242b, and the image data of each color component generated in the second field period. Do not output. Further, the first stage processing circuit 241 outputs to the luminance component generation circuit 243 both the image data of each color component sequentially generated in the first field period and the second field period.

  The color component memories 242r, 242g, and 242b are memories for temporarily storing RGB color component image data output from the first stage processing circuit 241. Each of these memories 242r, 242g, and 242b outputs each color component image data at a timing according to the reference signal. However, the R component image data is output to the adder 247, but the G component image data and the B component image data are output to the post-processing circuit 248.

  The luminance component generation circuit 243 is a circuit that generates image data of the luminance component (Y component) in the YCrCb color space based on the RGB color component image data output from the first stage processing circuit 241. In other words, the luminance component generation circuit 243 conceptually sets the gradation values (R, G, B) of pixels at the same position in the RGB color component image data to Y = 0.30R + 0.59G + 0.11B. By calculating by substituting into the equation, the luminance value Y of the pixel at that position is calculated.

  The luminance component generation circuit 243 outputs the Y component image data based on the color component image data output from the first stage processing circuit 241 after the first field period to the first luminance component memory 244a, and outputs the second luminance component memory 244a. Y component image data based on each color component image data output from the first stage processing circuit 241 after the field period is output to the second luminance component memory 244b.

  Each of the luminance component memories 244a and 244b is a memory for temporarily storing Y component image data. Each of these memories 244a and 244b outputs each Y component image data to the affected part image data generation circuit 245 at a timing according to the reference signal.

  The affected part image data generation circuit 245 is a circuit that generates affected part image data based on each Y component image data output from each of the luminance component memories 244a and 244b. More specifically, the affected part image data generation circuit 245 first performs a normalization process for equalizing the gradation widths of both Y component image data, and then the gradations of pixels at the same position in both Y component image data. The absolute value of the difference between the values is calculated, and image data in which the absolute value of the difference between the pixels is the gradation value of itself is generated as the affected part image data.

  The switch circuit 246 is a circuit for opening and closing between the affected part image data generation circuit 245 and the adder 247. The switch circuit 246 is controlled by the system control unit 22 so that the affected part image data is not output to the adder 247 in the normal observation mode, and the affected part image data is not output in the first to third special observation modes. The data is output to the adder 247.

  The adder 247 is a circuit that adds the affected part image data to the R component image data only when the affected part image data is input. That is, the adder 247 passes the R component image data as it is to the post-processing circuit 248 in the normal observation mode, and the R component image data obtained by adding the affected part image data in the first to third special observation modes. The data is sent to the post-processing circuit 248.

  The post-stage processing circuit 248 uses the R component image data output from the adder 247 and the G component image data and B component image data output from the G component memory 242g and the B component memory 242b, respectively, for monitor output. It is a circuit for converting into an image signal. Processing performed on each color component image data in the post-stage processing circuit 248 includes digital-analog conversion, encoding, impedance matching, and the like. The post-processing circuit 248 generates a separate video signal and a composite video signal by performing the above-described processing on each color component image data, and outputs it to the monitor 40.

  When the monitor 40 receives the video signal output from the light source processor device 20, the monitor 40 displays a color image based on the video signal.

  Returning to FIG. 2, the first light source unit 25 is a unit for emitting light to be introduced into the base end face of the light guide 15. FIG. 9 is a configuration diagram schematically showing the inside of the first light source unit 25.

  The first light source unit 25 functions alone, but when the special light source device 30 is connected to the light source processor device 20, it cooperates with the second light source unit 31 provided in the special light source device 30. Function. In order to explain all such functions, FIG. 9 schematically shows the internal configuration of the second light source unit 31 as well as the first light source unit 25.

  By the way, in 1st Embodiment, in order to connect the light source processor apparatus 20 and the special light source device 30, the predetermined cable is prepared. This cable is configured by bundling light guides LG made of a large number of flexible optical fibers together with a plurality of signal lines. However, in FIG. 9, for convenience, the light guide LG is not illustrated in a state of being bundled with a plurality of signal lines.

  When the connectors at both ends of the cable are connected to the light source processor device 20 and the special light source device 30, respectively, the plurality of signal lines are terminals provided in the light source processor device 20 and the special light source device 30, respectively. And one end of the light guide LG is fixed in a state of being inserted into the housing of the special light source device 30, and the other end of the light guide LG is installed in the housing of the light source processor device 20. Fixed in the inserted state.

  When the end portion of the light guide LG is fixed to the housing of the light source processor device 20, the extension line of the central axis of the end portion of the light guide LG is connected to the light source processor device 20 via the connector portion 10d. It is orthogonal to the extension of the central axis of the light guide 15 that is fixed.

  The first light source unit 25 includes a white light lamp 251, a first rotating plate 252, a first motor 253, a first stage mechanism 254, a second motor 255, a dichroic mirror 256, a second stage mechanism 257, and a third motor 258. Is provided.

  The white light lamp 251 is a light source that emits white light including wavelength components in the entire visible band of about 400 nm to about 700 nm. The white light lamp 251 is disposed at a position where white light can be vertically incident on the base end face of the light guide 15. A power supply circuit 251 a is connected to the white light lamp 251.

  The power supply circuit 251 a is a circuit for starting or stopping the supply of power to the white light lamp 251, and is connected to the system control unit 22. The power supply circuit 251a emits white light to the white light lamp 251 by supplying power to the white light lamp 251 when the operation mode is the normal observation mode or the first special observation mode.

  The first rotating plate 252 includes a disk having two through holes and an optical filter fitted in both through holes. FIG. 10 is a front view of the first rotating plate 252. The zone-like region between the center of the first rotating plate 252 and the outer peripheral edge thereof will be described in order by dividing it into two semicircular arc-like regions.

  One through hole is formed in one semicircular arc region. The through hole is formed in the shape of a band that is curved in the shape of a quadrant arc, and the center of the quadrant coincides with the center of the first rotating plate 252. Further, the through hole occupies one side when the semicircular arc-shaped region is divided in half. A visible light transmission filter 252a is fitted in the through hole. The visible light transmission filter 252a is an optical filter that transmits visible light in a wavelength band of about 450 nm to 700 nm (hereinafter referred to as “visible illumination light”) and removes light in other wavelength bands.

  One through hole is also formed in the other semicircular arc region. The through hole is formed in a semicircular arc-shaped band shape, and the center of the semicircular arc coincides with the center of the first rotating plate 252. Further, the through hole occupies this semicircular arc region. The excitation light transmission filter 252b is fitted in the through hole. The excitation light transmission filter 252b is an optical filter for extracting the excitation light from the white light. More specifically, the excitation light transmission filter 252b is a first wavelength band (about 400 nm to 450 nm) of the above-described excitation light (hereinafter, “ It is an optical filter that transmits light in other wavelength bands by transmitting "visible excitation light".

  The first motor 253 is an actuator for rotating the first rotary plate 252 configured as described above, and the first rotary plate 252 is driven in a state coaxial with the drive shaft of the first motor 253. It is fixed near the tip of the shaft. A synchronization driver 253a is connected to the first motor 253.

  The synchronization driver 253a is a circuit for controlling the driving of the first motor 253. The synchronization driver 253a is connected to the timing control unit 21 and the system control unit 22, and drives the first motor 253 according to the reference signal described above when the operation mode is the first to third special observation modes.

  An optical sensor 253b for detecting the rotational phase of the first rotary plate 252 is disposed in the vicinity of the center of the first rotary plate 252, and the synchronization driver 253a receives a signal obtained from the optical sensor 253b. Based on the above, the rotational phase of the first rotating plate 252 is synchronized with the timing indicated by the reference signal. However, the means for detecting the rotational phase of the first rotating plate 252 may be a detector (sensor) assembled to the first motor 253, for example, instead of the optical sensor 253b.

  The first stage mechanism 254 is a mechanism for translating an object installed on the stage only in a direction orthogonal to the direction of white light emitted from the white light lamp 251. On the stage, the first stage mechanism 254 is described above. A first motor 253 is installed.

  On the stage, the first motor 253 directs the drive shaft in a direction orthogonal to the moving direction of the stage. Therefore, the first rotating plate 252 is perpendicular to the direction parallel to the optical path of white light. When the first stage mechanism 254 is driven in the forward and reverse directions, the first rotating plate 252 fixed to the drive shaft of the first motor 253 is in the optical path of the white light emitted from the white light lamp 251. It is inserted and removed vertically.

  The second motor 255 is an actuator for driving the first stage mechanism 254, and a movement driver 255 a is connected to the second motor 255. The moving driver 255 a is a circuit for controlling the driving of the second motor 255 and is connected to the system control unit 22.

  When the operation mode is switched to the normal observation mode, the moving driver 255a controls the second motor 255 to move the first stage mechanism 254 until the first rotating plate 252 is pulled out from the optical path of white light. To drive.

  In addition, when the operation mode is switched to the first special observation mode, the movement driver 255a controls the second motor 255 to perform the first operation until the first rotating plate 252 is inserted into the white light path. The stage mechanism 254 is driven.

  The first stage mechanism 254 is attached with a position sensor 255b for detecting the position of the stage. The position sensor 255b is connected to the system control unit 22. The system control unit 22 detects the amount of movement of the stage based on the signal obtained from the position sensor 255b, and instructs the movement driver 255a to drive the second motor 255 until the stage reaches a predetermined position.

  The dichroic mirror 256 is a mirror that transmits light having a wavelength band of about 450 nm or more and reflects light having a wavelength band of less than about 450 nm.

  The second stage mechanism 257 is a mechanism for translating an object placed on the stage only in the direction of the central axis of the end portion of the light guide LG. On the stage, the above-described dichroic mirror 256 is provided. is set up.

  On this stage, the dichroic mirror 256 is inclined 45 degrees with respect to the direction in which the white light is emitted from the white light lamp 251. When the second stage mechanism 257 is driven in the forward and reverse directions, the dichroic mirror 256 is inserted into and removed from the optical path of white light emitted from the white light lamp 251.

  The third motor 258 is an actuator for driving the second stage mechanism 257, and a movement driver 258a is connected to the third motor 258. The moving driver 258 a is a circuit for controlling the driving of the third motor 258 and is connected to the system control unit 22.

  When the operation mode is switched to the normal observation mode or the first special observation mode, the moving driver 258a controls the third motor 258 so that the second stage until the dichroic mirror 256 is extracted from the optical path of white light. The mechanism 257 is driven.

  Further, when the operation mode is switched to the second special observation mode or the third special observation mode, the movement driver 258a controls the third motor 258 so that the dichroic mirror 256 is inserted in the optical path of white light. Until the second stage mechanism 257 is driven. When the stage is in this position, the extension line of the center axis of the light guide 15 and the extension line of the center axis of the end portion of the light guide LG intersect each other on the reflection surface of the dichroic mirror 256, It intersects with this reflection surface in a state inclined at 45 degrees with respect to the reflection surface.

  The second stage mechanism 258 is provided with a position sensor 258b for detecting the position of the stage. The position sensor 258b is connected to the system control unit 22. The system control unit 22 detects the amount of movement of the stage based on the signal obtained from the position sensor 258b, and instructs the movement driver 258a to drive the third motor 258 until the stage reaches a predetermined position.

  The second light source unit 31 includes a laser light source 311, a first folding mirror 312, an ultraviolet lamp 313, a second folding mirror 314, a third stage mechanism 315, a fourth motor 316, a second rotating plate 317, and a fifth motor. 318 is provided.

  The laser light source 311 is a light source that emits a laser beam having a third wavelength band of about 400 nm to about 430 nm (hereinafter referred to as “laser excitation light”), and a power supply circuit 311 a is connected to the laser light source 311. ing.

  The power supply circuit 311a is a circuit for starting or stopping the supply of power to the laser light source 311. By connecting the light source processor device 20 and the special light source device 30 with the above-described cable, the light source processor device. 20 system control units 22 are connected. Then, the power supply circuit 311a emits laser excitation light to the laser light source 311 by supplying power to the laser light source 311 when the operation mode is the third special observation mode.

  The first folding mirror 312 is a total reflection mirror that bends the optical path of the laser excitation light emitted from the laser light source 311 and vertically enters the end face of the light guide LG.

  The ultraviolet light lamp 313 is a light source that emits ultraviolet light having a wavelength component in the ultraviolet band of about 350 nm to about 380 nm (hereinafter referred to as “ultraviolet excitation light”). The ultraviolet light lamp 313 includes a power supply circuit 313a. Is connected.

  The power supply circuit 313a is a circuit for starting or stopping the supply of electric power to the ultraviolet light lamp 313, and the light source processor device 20 and the special light source device 30 are connected by the above-described cable, whereby the light source processor It is connected to the system control unit 22 of the apparatus 20. The power supply circuit 313a emits ultraviolet excitation light to the ultraviolet light lamp 313 by supplying power to the ultraviolet light lamp 313 when the operation mode is the second special observation mode.

  The second folding mirror 314 is a total reflection mirror that bends the optical path of the ultraviolet excitation light emitted from the ultraviolet lamp 313.

  The third stage mechanism 315 is a mechanism for translating an object installed on the stage only in a direction orthogonal to the central axis of the end portion of the light guide LG, and the ultraviolet light described above is placed on the stage. A lamp 313 and a second folding mirror 314 are installed.

  On this stage, the ultraviolet lamp 313 is installed such that the emission direction of the ultraviolet excitation light is parallel to the moving direction of the stage, while the second folding mirror 314 is provided from the ultraviolet lamp 313. It is inclined 45 degrees with respect to the emission direction of the ultraviolet excitation light and the direction of the central axis of the end portion of the light guide LG. When the third stage mechanism 315 is driven in the forward and reverse directions, the second folding mirror 314 is emitted from the laser light source 311 and reflected by the first folding mirror 312 with respect to the optical path of the laser excitation light. It is inserted and removed.

  The fourth motor 316 is an actuator for driving the third stage mechanism 315, and a movement driver 316a is connected to the fourth motor 316.

  The moving driver 316a is a circuit for controlling the driving of the fourth motor 316, and the light source processor device 20 and the special light source device 30 are connected by the above-described cable, whereby the system of the light source processor device 20 is connected. Connected to the control unit 22.

  The movement driver 316a controls the fourth motor 316 when the operation mode is switched to the third special observation mode, and the third stage mechanism until the second folding mirror 314 is pulled out from the optical path of the laser excitation light. 315 is driven. When the stage is in this position, the laser excitation light from the laser light source 311 travels toward the end face of the light guide LG.

  In addition, when the operation mode is switched to the second special observation mode, the movement driver 316a controls the fourth motor 316 until the second folding mirror 314 is inserted in the optical path of the laser excitation light. The three stage mechanism 315 is driven. When the stage is at this position, the ultraviolet excitation light from the ultraviolet lamp 313 travels toward the end face of the light guide LG.

  The third stage mechanism 315 is attached with a position sensor 316b for detecting the position of the stage. The position sensor 316b is connected to the system control unit 22 of the light source processor device 20 by connecting the light source processor device 20 and the special light source device 30 with the cable described above. The system control unit 22 detects the amount of movement of the stage based on the signal obtained from the position sensor 316b, and instructs the movement driver 316a to drive the fourth motor 316 until the stage reaches a predetermined position.

  The second rotary plate 317 is a disc having one through hole. FIG. 11 is a front view of the second rotating plate 317. The second rotating plate 317 is a disc having the same size as the first rotating plate 252. However, the second rotating plate 317 does not have a quadrant arc-shaped through hole equivalent to the through hole into which the visible light transmission filter 252a is fitted in the first rotating plate 252. The second rotating plate 317 has a semicircular arc-shaped through hole 317a equivalent to the through hole into which the excitation light transmitting filter 252b in the first rotating plate 252 is fitted. , Nothing is fitted.

  The fifth motor 318 is an actuator for rotating the second rotating plate 317 configured as described above, and the second rotating plate 317 is driven in a state coaxial with the drive shaft of the fifth motor 318. It is fixed near the tip of the shaft. The fifth motor 318 is connected to a synchronization driver 318a.

  The synchronization driver 318a is a circuit for controlling the driving of the fifth motor 318, and the timing control of the light source processor device 20 is performed by connecting the light source processor device 20 and the special light source device 30 with the above-described cable. Connected to the unit 21 and the system control unit 22. The synchronization driver 318a drives the fifth motor 318 in accordance with the reference signal described above when the operation mode is the second special observation mode and the third special observation mode.

  An optical sensor 318b for detecting the rotational phase of the second rotary plate 317 is disposed in the vicinity of the outer edge of the second rotary plate 317, and the synchronization driver 318a receives a signal obtained from the optical sensor 318b. Based on the above, the rotational phase of the second rotating plate 317 is synchronized with the timing indicated by the reference signal. However, the means for detecting the rotational phase of the second rotating plate 317 may be a detector (sensor) assembled to the fifth motor 318, for example, instead of the optical sensor 318b.

  Since the electronic endoscope system according to the first embodiment is configured as described above, the operator of this electronic endoscope system can observe the inside of the body cavity by the following procedure.

  First, the operator connects the electronic endoscope 10, the light source processor device 20, and the monitor 40, and turns on the light source processor device 20 and the monitor 40. Subsequently, after the operator inserts the distal end of the insertion portion 10a of the electronic endoscope 10 into the body cavity, the operator operates the switch SW in the operation portion 10b of the electronic endoscope 10 to change the operation mode to the normal observation mode. Switch to.

  When the mode is switched to the normal observation mode, the dichroic mirror 256 and the first rotating plate 252 are extracted from the optical path of white light emitted from the white light lamp 251. Therefore, white light having a wavelength band of about 400 nm to 700 nm is always incident on the base end surface of the light guide 15, and white light is continuously emitted from the distal end of the insertion portion 10 a of the electronic endoscope 10. The body cavity is illuminated.

  Of the illumination light reflected from the surface of the body cavity wall, the light transmitted through the objective lens 12 is incident on the imaging surface of the imaging element 16. At this time, an image (normal image) in the body cavity is formed on the imaging surface by the objective lens 12.

  The normal image formed on the imaging surface is captured by the image sensor 16 and an image signal is output to the image processing unit 24. In the image processing unit 24, the first-stage processing circuit 241 performs predetermined processing on the image signal to generate image data of each color component of RGB. Each color component image data is output to the post-processing circuit 248 without adding the affected part image data, and is converted into a video signal which is an image signal for monitor output in the post-processing circuit 248. The video signal is output to the monitor 40.

  Therefore, a normal image is displayed on the monitor 40 as a color normal observation image. The operator can observe the state of the body cavity wall while viewing the normal observation image.

  Further, the operator observes the special observation image obtained by using the visible excitation light having the first wavelength band for the part selected through the observation of the normal observation image on the monitor 40. Specifically, the operator once pulls out the insertion portion 10a of the electronic endoscope 10 from the body cavity, operates the switch SW in the operation portion 10b, and switches the operation mode to the tip detection mode.

  When the mode is switched to the tip detection mode, a voltage is applied to the electrode portion 19 bonded to the flat surface 10p of the small-diameter protruding portion 10e at the tip of the insertion portion 10a. Therefore, the operator attaches the first cap 18 to the distal end of the insertion portion 10a. When the first cap 18 is attached to the distal end of the insertion portion 10a, the first electrode plate 191 and the second electrode plate 192 of the electrode portion 19 are short-circuited by the short-circuit portion 184 of the first cap 18, whereby the electrode portion 19 The voltage application to is stopped, and the operation mode is switched to the first special observation mode.

  Then, the dichroic mirror 256 is pulled out from the optical path of white light emitted from the white light lamp 251 and the first rotating plate 252 is inserted into the optical path of white light. Further, the first rotating plate 252 is rotated, and the visible light transmission filter 252a and the excitation light transmission filter 252b are alternately inserted into the white light optical path in synchronization with the first field period and the second field period, respectively. For this reason, visible illumination light having a wavelength band of about 450 nm to 700 nm and visible excitation light having a first wavelength band (about 400 nm to 450 nm) are alternately incident on the base end surface of the light guide 15, thereby causing electronic internal viewing. Visible illumination light and visible excitation light are alternately emitted from the distal end of the insertion portion 10 a of the mirror 10.

  Thereafter, when the operator inserts the distal end of the insertion portion 10a of the electronic endoscope 10 into the body cavity, visible illumination light and visible excitation light are alternately irradiated into the body cavity. Note that FIG. 12 shows the wavelength bands of visible illumination light and visible excitation light emitted from the distal end of the insertion portion 10a of the electronic endoscope 10, respectively.

  In the first field period in which the visible illumination light is irradiated into the body cavity, the body cavity is illuminated. And the light which went to the objective lens 12 among the visible illumination lights reflected by the surface of the body cavity wall passes the excitation light removal filter 182 which the 1st cap 18 has, and has the same 1st wavelength as visible excitation light. After the wavelength component of the band is removed (the visible illumination light is not substantially removed because it does not have the wavelength component), it enters the imaging surface of the imaging device 16. At this time, an image in the body cavity (normal image) is formed by the objective lens 12 on the imaging surface.

  In the second field period in which the visible excitation light is irradiated into the body cavity, the living tissue under the body cavity wall is excited to emit fluorescence, and the visible excitation light is reflected on the surface of the body cavity wall. And the light which went to the objective lens 12 among the light containing fluorescence and visible excitation light passes the excitation light removal filter 182 which the 1st cap 18 has, and has the same 1st wavelength band as visible excitation light. Wavelength components are removed. That is, the visible excitation light and a part of the fluorescence are removed from the light including the fluorescence and the visible excitation light. The remaining fluorescence transmitted through the excitation light removing filter 182 and the objective lens 12 is incident on the imaging surface of the imaging device 16. At this time, an image in the body cavity (fluorescent image) is formed on the imaging surface by the objective lens 12.

  The normal image and the fluorescence image alternately formed on the imaging surface are picked up by the image pickup device 16, and their image signals are sequentially output to the image processing unit 24. In the image processing unit 24, the first-stage processing circuit 241 performs predetermined processing on the image signal, and in the first field period, each color component image data (normal image data) based on the normal image is stored in each color component memory 242r, 242g, 242b. The luminance component generation circuit 243 outputs the color component image data (fluorescence image data) based on the fluorescent image to the luminance component generation circuit 243 in the second field period.

  When the luminance component generation circuit 243 acquires each color component image data based on the normal image in the first field period, the luminance component generation circuit 243 extracts the luminance component image data and outputs it to the first luminance component memory 244a, and each color component image based on the fluorescence image. When the data is acquired in the second field period, the luminance component image data is extracted and output to the second luminance component memory 244b. Then, based on the luminance component image data in the first and second luminance component memories 244a and 244b, the affected area image data generation circuit 245 generates affected area image data.

  Then, after the affected part image data is added to the R component image data in each color component image data based on the normal image, each color component image data is a video that is an image signal for monitor output in the post-processing circuit 248. This video signal is output to the monitor 40.

  Therefore, a special image generated based on the normal image and the fluorescent image is displayed on the monitor 40 as a color special observation image. The operator can identify the contours and irregularities of the body cavity wall while looking at the special observation image, and a biological body that emits relatively weak fluorescence due to the red spots in the image as spots or lumps. A group of tissues, that is, a site where a lesion such as a tumor or cancer is highly likely to be recognized can be recognized.

  Further, when necessary, the operator changes the wavelength band of the excitation light irradiated into the body cavity to the second wavelength band and observes the special observation image. Specifically, the operator pulls out the distal end of the insertion portion 10a of the electronic endoscope 10 from the body cavity and removes the first cap 18 from the distal end of the insertion portion 10a. Subsequently, the operator sets the special light source device 30 at a predetermined position, connects the special light source device 30 and the light source processor device 20 with the above-described predetermined cable, and turns on the main power supply of the special light source device 30. .

  Thereafter, the operator operates the switch SW in the operation unit 10b of the electronic endoscope 10 to temporarily switch to the normal observation mode and then return the switch SW again to restart the tip detection mode. Alternatively, the operator once pulls out the connector portion 10d of the electronic endoscope 10 from the light source processor device 20 and inserts the connector portion 10d into the light source processor device 20 again to restart the tip detection mode.

  After the tip detection mode is restarted, when the operator attaches the second cap 18 ′ to the tip of the insertion portion 10a, the first electrode plate of the electrode portion 19 is short-circuited by the short-circuit portion 184 ′ of the second cap 18 ′. When 191 and the third electrode plate 193 are short-circuited, the operation mode is switched to the second special observation mode.

  Then, the dichroic mirror 256 and the first rotating plate 252 are inserted into the optical path of the white light emitted from the white light lamp 251. Further, the first rotating plate 252 is rotated, and the visible light transmission filter 252a and the excitation light transmission filter 252b are alternately inserted into the white light optical path in synchronization with the first field period and the second field period, respectively. Therefore, visible illumination light having a wavelength band of about 450 nm to 700 nm and visible excitation light of the first wavelength band (about 400 nm to 450 nm) are alternately incident on the dichroic mirror 256.

  However, since the dichroic mirror 256 transmits only light having a wavelength band of about 450 nm or more, only visible illumination light (about 450 nm to 700 nm) extracted by the first rotating plate 252 in the first field period is transmitted from the light guide 15. Visible excitation light (about 400 nm to 450 nm) that reaches the base end face and is extracted by the first rotating plate 252 in the second field period does not reach the base end face of the light guide 15.

  In addition, after switching to the second special observation mode, the second folding mirror 314 is inserted into the optical path of the laser excitation light after being emitted from the laser light source 311 and reflected by the first folding mirror 312, and ultraviolet light. The ultraviolet excitation light emitted from the lamp 313 is reflected by the second folding mirror 314 and travels toward the end face of the light guide LG.

  Further, the second rotating plate 317 is rotated, and the through hole 317a of the second rotating plate 317 is repeatedly inserted into the optical path of the ultraviolet excitation light while synchronizing with the second field period. Therefore, ultraviolet excitation light is repeatedly introduced into the end face of the light guide LG with a predetermined time interval, and the ultraviolet excitation light guided to the light guide LG enters the dichroic mirror 256.

  Since the dichroic mirror 256 reflects only light having a wavelength band of less than about 450 nm, ultraviolet excitation light (about 350 nm to 380 nm) emitted from the end face of the light guide LG toward the dichroic mirror 256 in the second field period. Is reflected by the dichroic mirror 256 and reaches the base end face of the light guide 15.

  In this manner, visible illumination light and ultraviolet excitation light alternately and repeatedly enter the base end face of the light guide 15 in synchronization with the first field period and the second field period, and the insertion portion of the electronic endoscope 10 Visible illumination light and ultraviolet excitation light are alternately emitted from the tip of 10a.

  Thereafter, when the operator inserts the distal end of the insertion portion 10a of the electronic endoscope 10 into the body cavity, visible illumination light and ultraviolet excitation light are alternately irradiated into the body cavity. Note that FIG. 13 shows the wavelength bands of visible illumination light and ultraviolet excitation light emitted from the distal end of the insertion portion 10a of the electronic endoscope 10, respectively.

  In the first field period in which the visible illumination light is irradiated into the body cavity, the body cavity is illuminated. Of the visible illumination light reflected from the surface of the body cavity wall, the light directed toward the objective lens 12 passes through the excitation light removal filter 182 ′ of the second cap 18 ′, thereby being the same as the ultraviolet excitation light. After the wavelength components in the two wavelength bands are removed (illumination light does not have the wavelength component, it is not substantially removed), and then enters the imaging surface of the imaging device 16. At this time, an image in the body cavity (normal image) is formed by the objective lens 12 on the imaging surface.

  In the second field period in which the ultraviolet excitation light is irradiated into the body cavity, the living tissue under the body cavity wall is excited to emit fluorescence, and the ultraviolet excitation light is reflected on the surface of the body cavity wall. And the light which went to the objective lens 12 among the light containing fluorescence and ultraviolet excitation light passes the excitation light removal filter 182 'which 2nd cap 18' has, and is the 2nd same wavelength as ultraviolet excitation light. The wavelength component of the band is removed. That is, the ultraviolet excitation light and a part of the fluorescence are removed from the light including the fluorescence and the ultraviolet excitation light. The remaining fluorescence transmitted through the excitation light removal filter 182 ′ and the objective lens 12 is incident on the imaging surface of the imaging device 16. At this time, an image in the body cavity (fluorescent image) is formed on the imaging surface by the objective lens 12.

  As a result, normal images and fluorescent images are alternately formed on the imaging surface. Then, after processing similar to that in the case where the wavelength band of the excitation light is the first wavelength band is performed in the image processing unit 24, a color special observation image is displayed on the monitor 40. Thereby, the operator can observe the special observation image when the wavelength band of the excitation light is changed to the second wavelength band.

  Further, when necessary, the operator changes the wavelength band of the excitation light irradiated into the body cavity to the third wavelength band and observes the special observation image. Briefly, the operator once pulls out the distal end of the insertion portion 10a from the body cavity, removes the second cap 18 "from the distal end of the insertion portion 10a, restarts the distal end detection mode as described above, and inserts the insertion portion 10a. A third cap 18 ″ is attached to the tip of the part 10a to switch the operation mode to the third special observation mode.

  Then, the dichroic mirror 256 is inserted into the optical path of the white light emitted from the white light lamp 251, the first rotating plate 252 is inserted, and the first rotating plate 252 is further rotated. As a result, only visible illumination light (about 450 nm to 700 nm) extracted by the first rotating plate 252 in the first field period reaches the base end face of the light guide 15.

  On the other hand, from the optical path of the laser excitation light after being emitted from the laser light source 311 and reflected by the first folding mirror 312, the second folding mirror 314 is pulled out, the second rotating plate 317 is rotated, and the second rotating plate is rotated. The through hole 317a of 317 is repeatedly inserted into the optical path of the laser excitation light while synchronizing with the second field period. As a result, laser excitation light (about 400 nm to 430 nm) emitted from the end face of the light guide LG toward the dichroic mirror 256 in the second field period is reflected by the dichroic mirror 256 and reaches the base end face of the light guide 15. .

  In this way, visible illumination light and laser excitation light alternately and repeatedly enter the base end face of the light guide 15 in synchronization with the first field period and the second field period, and the insertion portion of the electronic endoscope 10 Visible illumination light and laser excitation light are alternately emitted from the tip of 10a.

  Thereafter, when the operator inserts the distal end of the insertion portion 10a of the electronic endoscope 10 into the body cavity, visible illumination light and laser excitation light are alternately irradiated into the body cavity. Note that FIG. 14 shows the wavelength bands of visible illumination light and laser excitation light emitted from the distal end of the insertion portion 10a of the electronic endoscope 10, respectively.

  Then, in the first field period in which the visible illumination light is irradiated into the body cavity, the excitation light removal filter 182 ″ and the objective lens 12 included in the third cap 18 ″ out of the visible illumination light reflected from the surface of the body cavity wall. The passed light is incident on the imaging surface of the image sensor 16, and an image (normal image) in the body cavity is formed on the imaging surface by the objective lens 12.

  Further, in the second field period in which the laser excitation light is irradiated into the body cavity, the objective lens out of the light including the fluorescence emitted from the living tissue below the body cavity wall and the laser excitation light reflected from the surface of the body cavity wall The light directed to 12 passes through the excitation light removal filter 182 ″ of the third cap 18 ″, so that the wavelength component in the same third wavelength band as the laser excitation light is removed. Then, the remaining fluorescence that has passed through the excitation light removing filter 182 ″ and the objective lens 12 is incident on the imaging surface of the imaging device 16, and an image (fluorescence image) in the body cavity is formed on the imaging surface of the objective lens 12. Formed by.

  As a result, normal images and fluorescent images are alternately formed on the imaging surface. Then, after processing similar to that in the case where the wavelength band of the excitation light is the first wavelength band is performed in the image processing unit 24, a color special observation image is displayed on the monitor 40. Thereby, the operator can observe the special observation image when the wavelength band of the excitation light is changed to the third wavelength band.

  As described above, according to the electronic endoscope system of the first embodiment, the operator removes the cap 18 from the distal end of the insertion portion 10a of the electronic endoscope 10 and switches the switch SW on the operation portion 10b. The operation mode can be easily switched to the normal observation mode simply by pressing the button.

  Further, according to the electronic endoscope system of the first embodiment, after the operator switches the operation mode to the tip detection mode by operating the switch SW on the operation unit 10b of the electronic endoscope 10, The operation mode can be switched to the special observation mode simply by selecting one of the three caps 18, 18'18 "and attaching the selected cap to the distal end of the insertion portion 10a of the electronic endoscope 10. .

  Further, after removing the cap attached to the distal end of the insertion portion 10a and restarting the distal end detection mode, if another cap different from the removed cap is attached to the distal end of the insertion portion 10a, the operation mode is changed. Can be switched to the special observation mode. Therefore, the operator can easily change the wavelength band of the excitation light used for special observation.

  The cap exchanged together with the switching of the special observation mode has an excitation light removal that can remove light in the same wavelength band as the excitation light emitted from the tip of the electronic endoscope 10 in the special observation mode. A filter 182 is provided. Therefore, even if the wavelength band of the excitation light is changed by exchanging the cap, light having the same wavelength band as the wavelength band of the excitation light is always removed from the light toward the image sensor 16. It becomes. Therefore, no matter which cap 18 is attached to the distal end of the insertion portion 10a, an image in the body cavity (stray light image) formed by the excitation light reflected from the surface of the body cavity wall is always prevented from being mixed with the fluorescent image. The

  Further, according to the electronic endoscope system of the first embodiment, when performing special observation, the identification information is not viewed from among the three caps 18, 18 ′, 18 ″ when the special observation is performed regardless of the wavelength band of the excitation light. It is only necessary to attach one cap appropriately selected to the tip of the insertion portion 10a, and even when a cap is properly selected, a special observation mode in which excitation light in a wavelength band corresponding to the cap is emitted. Therefore, the operator can concentrate on observation in the body cavity without being distracted by the operation of the electronic endoscope system.

  In addition, according to the electronic endoscope system of the first embodiment, the second light source unit 31 that emits excitation light of a special wavelength band such as ultraviolet excitation light or laser excitation light is provided with the first light source unit 25. The special light source device 30 is provided separately from the light source processor device 20 provided. For this reason, if a user who does not require excitation light in a special wavelength band prepares only the light source processor device 20 and the first cap 18, the cost of the electronic endoscope system can be reduced.

  As described above, the electronic endoscope system according to the first embodiment includes the special light source device 30 separately from the light source processor device 20 as a device for generating excitation light in a special wavelength band. However, the present invention is not limited to this. As a modification of the first embodiment, for example, the light source processor device 20 and the special light source device 30 are integrated by providing a function for generating excitation light of a special wavelength band inside the light source processor device 20. It may be configured as follows.

Embodiment 2

  The electronic endoscope system according to the second embodiment of the present invention has almost the same configuration as that of the first embodiment described above. The difference from the first embodiment is that the special light source device 30 is not provided and that the excitation light supplied from the light source processor device 20 to the base end surface of the light guide 15 is extracted from one white light lamp. . FIG. 15 is a configuration diagram schematically illustrating an electronic endoscope system according to the second embodiment.

  As shown in FIG. 15, the light source processor device 20 ′ of the second embodiment is similar to the light source processor device 20 of the first embodiment in that a timing control unit 21, a system control unit 22, a tip detection unit 23, and The image processing unit 24 is provided, and one light source unit 26 having a slightly different configuration from the first light source unit 25 of the first embodiment is provided.

  The light source unit 26 includes a white light lamp 261, a rotating plate 262, a first motor 263, a stage mechanism 264, and a second motor 265. Of these, the white light lamp 261, the first motor 263, and the stage. The mechanism 264 and the second motor 265 have the same functions as the white light lamp 251, the first motor 253, the first stage mechanism 254, and the second motor 255 provided in the first light source unit 25 of the first embodiment. Have.

  However, the rotating plate 262 has a configuration different from the first rotating plate 252 included in the first light source unit 25 of the first embodiment. FIG. 16 is a front view of the rotating plate 262. As shown in FIG. 16, the rotating plate 262 is equivalent to a region having a semicircular arc-shaped through hole in which the excitation light transmitting filter 252b is fitted in the first rotating plate 252 (see FIG. 10) of the first embodiment. The region has three through holes.

  These three through-holes are all formed in the shape of a band curved in a semicircular arcuate shape, and the centers of the semicircular arcs coincide with the center of the rotating plate 262. Further, these three through holes are arranged so as to divide this region into three equal parts along the radial direction. In these three through holes, three excitation light transmission filters 262b, 262c, and 262d having different transmission characteristics are fitted, respectively.

  Note that the system control unit 22 of the second embodiment causes the excitation light transmission filter inserted into the white light path from the white light lamp 261 when the rotating plate 262 rotates to change according to the switching of the special observation mode. In addition, the moving driver 265a is controlled. That is, the system control unit 22 of the second embodiment changes the distance from the optical path of the white light on the drive shaft of the first motor 263 according to the special observation mode, so that the first excitation light in the first special observation mode. In the second special observation mode, the second excitation light transmission filter 262c is inserted into the transmission filter 262b, and in the third special observation mode, the third excitation light transmission filter 262d is inserted into the optical path of white light.

  Therefore, also in the electronic endoscope system of the second embodiment shown in FIGS. 15 and 16, the wavelength band of the excitation light used for special observation can be obtained by replacing the cap attached to the tip of the insertion portion 10a. Can be easily changed.

External view of the electronic endoscope system of the first embodiment Configuration diagram schematically showing inside of electronic endoscope and light source processor device The perspective view for demonstrating the shape and mounting structure of a cap Back view of cap 4 is a cross-sectional side view of the cap cut along line AA in FIG. 4 when viewed from below in FIG. Explanatory drawing for demonstrating the method of attaching a cap to the front-end | tip of an insertion part Explanatory drawing for demonstrating each form of the short circuit part of three caps Configuration diagram schematically showing the inside of the image processing unit The block diagram which shows schematically the inside of a 1st light source part and a 2nd light source part Front view of the first rotating plate Front view of the second rotating plate Spectroscopic view showing wavelength bands of illumination light and visible excitation light emitted from the distal end of the insertion portion of the electronic endoscope in the first special observation mode Spectroscopic diagram showing wavelength bands of illumination light and ultraviolet excitation light emitted from the tip of the insertion portion of the electronic endoscope in the second special observation mode Spectroscopic view showing wavelength bands of illumination light and laser excitation light emitted from the distal end of the insertion portion of the electronic endoscope in the third special observation mode The block diagram which shows schematically the electronic endoscope system of 2nd Embodiment. Front view of rotating plate

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Electronic endoscope 11 Light distribution lens 12 Objective lens 15 Light guide 17 Driver 18 1st cap 18 '2nd cap 18 "3rd cap 182 Excitation light removal filter 184 Short circuit part 184' Short circuit part 184" Short circuit part 19 Electrode part 191 1st electrode plate 192 2nd electrode plate 193 3rd electrode plate 20 Light source processor apparatus 21 Timing control part 22 System control part 23 Tip detection part 24 Image processing part 25 1st light source part 251 White light lamp 252 1st rotation board 252a Visible light transmission filter 252b Excitation light transmission filter 253 First motor 254 First stage mechanism 255 Second motor 256 Optical element 257 Second stage mechanism 258 Third motor 30 Special light source device 31 Second light source 311 Laser light source 313 Ultraviolet light lamp 3 5 third stage mechanism 316 fourth motor 317 second rotation plate 318 fifth motor 40 monitor

Claims (18)

A tubular insertion portion for insertion into a body cavity;
An illumination optical system that guides light from the proximal end of the insertion portion to the distal end and emits the guided light from the distal end of the insertion portion;
An objective optical system that forms an image in the body cavity when the distal end of the insertion portion is inserted into the body cavity;
An endoscope provided with a photographing device for photographing an image formed by the objective optical system and generating image data;
An excitation light removal filter that removes excitation light in a specific wavelength band that excites biological tissue under a body cavity wall; and an identification unit that holds information corresponding to the specific wavelength band. A cap that is detachably attached to the distal end of the insertion portion in a state of being positioned in front of the optical system, and
A light source unit that introduces excitation light of one wavelength band selected from excitation light of a plurality of wavelength bands into the illumination optical system;
A detection unit that detects a wavelength band of excitation light that is removed by an excitation light removal filter included in a cap attached to a distal end of the insertion unit based on information held by an identification unit included in the cap;
An endoscope system comprising: a light source device including a light source control unit that causes the light source unit to select excitation light in a wavelength band detected by the detection unit. The identification unit provided in the cap is formed in a flat plate shape in which information corresponding to the specific wavelength band is expressed as a two-dimensional shape,
The detection unit of the light source device detects a wavelength band of excitation light removed by an excitation light removal filter included in a cap attached to a distal end of the insertion unit based on a difference in two-dimensional shape of the identification unit. The endoscope system according to claim 1, further comprising: The identification unit is a conductive metal plate,
The insertion portion of the endoscope includes a plurality of electrode plates of different combinations that are short-circuited to each other according to the difference in the two-dimensional shape of the metal plate at the distal end thereof,
The detection unit of the light source device has a wavelength band of excitation light to be removed by an excitation light removal filter included in a cap attached to a distal end of the insertion unit based on a short-circuited combination of the electrode plates. The endoscope system according to claim 2, wherein the endoscope system is detected. The light source unit of the light source device is
The endoscope system according to claim 1, 2 or 3, further comprising a plurality of light sources that respectively emit excitation light of the plurality of wavelength bands. The light source unit of the light source device is
At least one light source that emits excitation light of the plurality of wavelength bands;
A plurality of excitation light transmission filters for individually extracting the excitation light of each wavelength band from the light emitted by the light source;
The inside of Claim 1, 2, or 3 provided with the insertion mechanism which inserts one of these excitation light transmission filters in the optical path of the light which the said light source inject | emits toward the said illumination optical system. Endoscopic system. The endoscope system according to claim 4, wherein at least one of the light sources is a visible light source that emits light in a visible band. The endoscope system according to claim 4, wherein at least one of the light sources is an ultraviolet light source that emits light in an ultraviolet band. At least one of the plurality of excitation light transmission filters takes out excitation light in the ultraviolet band,
The endoscope system according to claim 7, wherein at least one of the plurality of excitation light removal filters removes excitation light in the ultraviolet band. The cap is formed in a substantially cylindrical shape with a bottom,
The endoscope system according to any one of claims 1 to 8, wherein the excitation light removing filter is fitted into a through hole formed in a bottom portion of the cap. The endoscope system according to claim 9, wherein the insertion portion of the endoscope has a protruding portion having a shape that can be fitted inside the cap at a distal end thereof. The inside of the cap and the protrusion are both formed in a D-cut shape, and when the protrusion is inserted into the cap, the cap cannot rotate with respect to the insertion portion. The endoscope system according to claim 10. A key groove and a key that can be fitted into the key groove are formed on the inner peripheral surface of the cap and the outer peripheral surface of the protrusion, respectively, and when the cap is attached to the protrusion, The endoscope system according to claim 11, wherein the key groove and the key are fitted. The endoscope system according to claim 12, wherein identification information for individually identifying each cap from among a large number of caps is described on an outer surface of the cap. The said cap has a through-hole arrange | positioned ahead of the said illumination optical system of the said endoscope, when it mounts | wears with the front-end | tip of the said insertion part, The one of Claim 1 thru | or 13 characterized by the above-mentioned. The endoscope system described. At the tip of the insertion portion of the endoscope, a forceps port is pierced,
The endoscope system according to any one of claims 1 to 14, wherein the cap has a through-hole disposed in front of the forceps opening when the cap is attached to a distal end of the insertion portion. The light source unit of the light source device alternately introduces excitation light of one wavelength band selected from the excitation light of the plurality of wavelength bands and illumination light for illuminating the inside of the body cavity,
The light source device includes fluorescence image data acquired from the imaging device during a period in which the excitation light is introduced into the illumination optical system, and from the imaging device in a period in which the illumination light is introduced into the illumination optical system. The endoscope system according to any one of claims 1 to 15, further comprising an image processing unit that generates image data for displaying a special image based on the acquired normal image data. . The image processing unit
Fluorescence image data is acquired from the imaging device during a period when the excitation light is introduced into the illumination optical system, and normal image data is acquired from the imaging device during a period when the illumination light is introduced into the illumination optical system. An image data acquisition unit to acquire,
Both the fluorescence image data and the normal image data acquired by the image data acquisition unit are converted into luminance data and subjected to normalization processing to make the gradation widths of both the image data equal, and then in the same position in both image data. Calculating an absolute value of a difference between gradation values of a pixel, and an affected part image data generation unit that generates image data in which the absolute value of the difference of each pixel is set to its own gradation value as affected part image data; and
17. The image processing apparatus according to claim 1, further comprising: an addition unit that generates special image data by adding the affected part image data generated by the affected part image data generation unit to the normal image data that is the basis thereof. The endoscope system according to Crab. The endoscope according to any one of claims 1 to 17, wherein the imaging device of the endoscope is an imaging device that captures an image formed by the objective optical system and generates image data. Mirror system.

Images