Endoscope

Abstract

The present invention provides an endoscope capable of effectively removing dirt from an auxiliary light irradiation window. The endoscope comprises, at a front end portion (12d) of an insertion portion, a front end surface (56); an objective lens (21) disposed on the front end surface (56); an air and water supply nozzle (25) for spraying fluid toward the objective lens (21); and a measurement auxiliary light lens (23) disposed on the front end surface (56) for emitting measurement auxiliary light. The measurement auxiliary light lens (23) is disposed within the fluid spraying range of the air and water supply nozzle (25) and between the objective lens (21) and the air and water supply nozzle (25).

Description

Technical Field

[0001] The present invention relates to an endoscope for irradiating auxiliary measurement light. Background Art

[0002] In the field of endoscopy, the distance to an observation object or the size of the observation object is acquired. For example, in Patent Document 1, auxiliary measurement light is irradiated onto a subject from an auxiliary light irradiation window provided at the distal end of an endoscope, thereby forming a light spot on the subject. Consequently, an endoscope processor determines the position of the light spot based on an image obtained by capturing the subject. The observation distance is then detected from the position of the light spot.

[0003] On the other hand, the distal end of the endoscope is equipped with an observation window, an illumination window, and a fluid jet nozzle, in addition to the auxiliary light irradiation window. The fluid jet nozzle sprays a fluid, such as cleaning water, to clean the observation window. In the endoscope described in Patent Document 2, the illumination window is positioned within the spray range of the fluid jet nozzle, and the cleaning water ejected from the fluid jet nozzle is sprayed onto the surface of the illumination window. This allows heat generated by light irradiation to be dissipated from the illumination window.

[0004] Previous technical literature

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. 2018 / 051680

[0007] Patent Document 2: Japanese Patent Application Laid-Open No. 2009-39462 Summary of the Invention

[0008] Technical issues to be solved by the invention

[0009] The distal end of an endoscope becomes dirty due to bodily fluids and other factors, so it is desirable to clean the auxiliary light illumination window along with the observation window. However, in Patent Document 2, cleaning water is sprayed onto the illumination window to dissipate heat, without considering cleaning the illumination window. Therefore, even with the same structure as Patent Document 2, but with an auxiliary light illumination window installed instead of the illumination window, cleaning of the auxiliary light illumination window is not feasible, resulting in inadequate removal of dirt.

[0010] The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide an endoscope capable of effectively removing dirt from an auxiliary light irradiation window.

[0011] Means for solving technical problems

[0012] The endoscope of the present invention comprises an insertion portion, a front end face, an observation window, a fluid injection nozzle, and an auxiliary light irradiation window. The auxiliary light irradiation window is positioned within the fluid injection range of the fluid injection nozzle and between the observation window and the fluid injection nozzle. The insertion portion is inserted into a subject. The front end face is disposed at the front end of the insertion portion. The observation window is disposed on the front end face. The fluid injection nozzle is disposed on the front end face and injects fluid toward the observation window. The auxiliary light irradiation window is disposed on the front end face and emits auxiliary measurement light.

[0013] Preferably, the fluid injection nozzle injects liquid or gas as the fluid, and when the liquid or gas is injected from the fluid injection nozzle toward the observation window, the flow velocity of the liquid reaching the position of the observation window is greater than 2 m / s, and the flow velocity of the gas reaching the position of the observation window is greater than 40 m / s.

[0014] Preferably, the auxiliary light irradiation window optical member constituting the auxiliary light irradiation window has a notch at a position facing the fluid ejecting nozzle.

[0015] Preferably, the notch is arranged at a position avoiding an optical path of the measurement auxiliary light when the measurement auxiliary light is emitted from the auxiliary light irradiation window.

[0016] Preferably, the fluid ejection nozzle is assembled to the insertion portion in a state of being in contact with the notch portion.

[0017] Preferably, the position of the auxiliary light irradiation window in the axial direction of the insertion portion is restricted by the notch portion abutting against the fluid ejection nozzle.

[0018] Preferably, the endoscope comprises: a front end body, which holds optical components for the auxiliary light irradiation window that constitute the auxiliary light irradiation window, a camera optical system including an observation window, and a fluid injection nozzle; and a front end cover, which covers the front end side of the front end body, and the optical components for the auxiliary light irradiation window have a notch at a position opposite to the front end cover.

[0019] Preferably, the position of the auxiliary light irradiation window in the axial direction of the insertion portion is restricted by the contact between the notch portion and the distal end cover.

[0020] Preferably, the optical component for the auxiliary light irradiation window is formed in a cylindrical shape, and the notch portion is an inclined surface inclined from the front end toward the outer peripheral surface of the optical component for the auxiliary light irradiation window.

[0021] Preferably, the outer diameter of the auxiliary light irradiation window is greater than 0.5 mm and less than 1.6 mm, the minimum distance between the outer edge of the observation window and the outer edge of the auxiliary light irradiation window, i.e., the first minimum distance, is greater than 0 mm and less than 1.5 mm, and the minimum distance between the outer edge of the auxiliary light irradiation window and the front end of the fluid injection nozzle, i.e., the second minimum distance, is greater than 0 mm and less than 0.5 mm.

[0022] Preferably, the installation position of the fluid injection nozzle relative to the front end face is the same as the position of the front end face of the auxiliary light irradiation window in the axial direction of the insertion portion, the front end face of the observation window is located on the front end side in the axial direction relative to the front end face of the auxiliary light irradiation window, and there is a continuous guide surface from the outer peripheral edge of the auxiliary light irradiation window to the outer peripheral edge of the observation window.

[0023] Preferably, the opening width of the fluid ejecting nozzle is smaller than the outer diameter of the observation window, and the guide surface is located within the fluid ejecting range of the fluid ejecting nozzle.

[0024] Preferably, the outer diameter of the auxiliary light irradiation window is smaller than the outer diameter of the observation window.

[0025] Effects of the Invention

[0026] According to the present invention, dirt on the auxiliary light irradiation window can be effectively removed. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is an external view of the endoscope system.

[0028] Figure 2 It is a plan view showing the distal end portion of the endoscope.

[0029] Figure 3 This is a block diagram showing the functions of an endoscope system.

[0030] Figure 4 This is a schematic diagram showing the structure of a measurement auxiliary light emitting unit.

[0031] Figure 5 It is an explanatory diagram showing a state where the insertion portion of the endoscope is inserted into a subject.

[0032] Figure 6 1 and 2 are explanatory diagrams showing the relationship between the distal end portion of the endoscope and the proximal end PN, the vicinity of the center PM, and the distal end PF within the observation distance range R1.

[0033] Figure 7 It is a cross-sectional view of the distal end portion of the endoscope.

[0034] Figure 8 This is a perspective view of the distal end of an endoscope.

[0035] Figure 9 This is a cross-sectional view of the main parts of the distal end portion of the endoscope.

[0036] Figure 10 It is a plan view of the distal end portion of the endoscope and is a plan view showing the dimensional relationship between the auxiliary light irradiation window, the observation window, and the fluid ejection nozzle.

[0037] Figure 11It is a plan view of the distal end portion of the endoscope, and is a plan view showing a state in which the fluid ejected from the fluid ejection nozzle spreads on the guide surface.

[0038] Figure 12 It is a plan view showing the distal end portion of an endoscope without a guide surface as a comparative example.

[0039] Figure 13 It is a cross-sectional view of the distal end portion of the endoscope in the second embodiment.

[0040] Figure 14 It is a perspective view showing the positional relationship between the fluid ejecting nozzle and the auxiliary light irradiation window in the second embodiment.

[0041] Figure 15 It is an exploded perspective view of the distal end portion of the endoscope in the second embodiment.

[0042] Figure 16 It is a perspective view showing the positional relationship between the fluid ejecting nozzle and the auxiliary light irradiation window in a modified example of the second embodiment.

[0043] Figure 17 It is a cross-sectional view of the distal end portion of the endoscope in the third embodiment.

[0044] Figure 18 It is a perspective view showing the positional relationship between the front end cover and the auxiliary light irradiation window in the third embodiment.

[0045] Figure 19 This is an image diagram showing the light spot and the first measurement mark when the observation distance is the near-end PN.

[0046] Figure 20 This is an image diagram showing the light spot and the first measurement mark when the observation distance is PM near the center.

[0047] Figure 21 This is an image diagram showing the light spot and the first measurement mark when the observation distance is the far-end PF.

[0048] Figure 22 This is an image diagram showing an example of a measurement image in which a measurement mark is superimposed on a subject image.

[0049] Figure 23 This is an image diagram showing an example of a measurement image in which a measurement mark is superimposed on a subject image.

[0050] Figure 24 This is an image diagram showing an example of a measurement image in which a measurement mark is superimposed on a subject image.

[0051] Figure 25 is an explanatory diagram showing the types of measurement marks. Figure 25(A) is a measurement mark having a line segment and a scale in the left direction of the light spot SP. Figure 25 (B) is a measurement mark having a line segment and a scale in the downward direction of the light spot SP. Figure 25 (C) is a measurement mark having a line segment and scale marks in the upper right direction of the light spot SP.

[0052] Figure 26 This is an explanatory diagram showing a first measuring mark of a cross, a cross with scale, a distorted cross, a circle and a cross, and a measuring point group type.

[0053] Figure 27 This is an image diagram showing three concentric circle marks of the same color.

[0054] Figure 28 This is an image diagram showing three concentric circle marks of different colors.

[0055] Figure 29 This is an image diagram showing distorted concentric circle marks.

[0056] Figure 30 This is an explanatory diagram showing a light emission pattern in which concentrated light is emitted intermittently.

[0057] Figure 31 This is a graphic diagram showing crosshairs and scales.

[0058] Figure 32 It is an explanatory diagram showing a light emission pattern in which linear measurement light is intermittently irradiated.

[0059] Figure 33 It is an explanatory diagram showing the stripe pattern light ZPL.

[0060] Figure 34 1 and 2 are explanatory diagrams showing light emission patterns of the stripe pattern light ZPL of phase X, phase Y, and phase Z.

[0061] Figure 35 It is an explanatory diagram showing the measurement light LPL in a grid-like pattern.

[0062] Figure 36 This is an explanatory diagram showing a light emission pattern of measurement light intermittently irradiating a grid pattern.

[0063] Figure 37 It is an explanatory diagram showing three-dimensional planar light TPL.

[0064] Figure 38 This is an explanatory diagram showing a light emission pattern of intermittently irradiating three-dimensional planar light. DETAILED DESCRIPTION

[0065] [First embodiment]

[0066] like Figure 1 As shown, the endoscope system 10 includes an endoscope 12, a light source device 14, a processor device 16, a monitor 18, and a user interface 19. The endoscope 12 is optically connected to the light source device 14 and electrically connected to the processor device 16. The processor device 16 is electrically connected to the monitor 18 (display unit) that displays images. The user interface 19 is connected to the processor device 16 and is used for various settings and operations on the processor device 16. The user interface 19 also includes a mouse, etc., in addition to the illustrated keyboard.

[0067] The endoscope 12 includes an insertion portion 12a for insertion into a subject, an operating portion 12b provided at the base end of the insertion portion 12a, a bending portion 12c provided at the distal end of the insertion portion 12a, and a distal end portion 12d. Operating the angle knob 12e of the operating portion 12b bends the bending portion 12c. This bending movement causes the distal end portion 12d to point in the desired direction.

[0068] The endoscope 12 has a normal mode and a length measurement mode, which are switched using a mode switch 13a provided on the operating unit 12b of the endoscope 12. The normal mode illuminates the observation object with illumination light. In the length measurement mode, the observation object is illuminated with illumination light or auxiliary measurement light, and measurement marks for determining the size of the observation object, etc., are displayed on the captured image of the observation object. The auxiliary measurement light is light used to measure the subject.

[0069] Furthermore, the operating unit 12b of the endoscope 12 is provided with a freeze switch 13b (still image acquisition command unit) for operating a still image acquisition command for acquiring a still image of the camera image. When the user operates the freeze switch 13b, the screen of the monitor 18 freezes and a warning sound (e.g., "beep") is emitted to indicate that a still image acquisition is being performed. Then, the still image of the camera image acquired before and after the freeze switch 13b is operated is stored in the still image storage unit 42 (see FIG. 4 ) in the processor device 16. Figure 3 ).

[0070] The still image storage unit 42 is a storage unit such as a hard disk or a USB (Universal Serial Bus) memory. If the processor device 16 is network-connectable, the still image of the captured image may be stored in a still image storage server (not shown) connected to the network, instead of or in addition to the still image storage unit 42.

[0071] Furthermore, a still image capture command can be issued using an operating device other than the freeze switch 13b. For example, a foot pedal can be connected to the processor device 16, and a still image capture command can be issued when the user operates the foot pedal (not shown). Mode switching can also be performed using the foot pedal. Furthermore, still image capture commands and mode switching can be issued using voice input, eye contact input, gesture input, and the like.

[0072] like Figure 2 As shown, the front end portion of the endoscope 12 is substantially circular and is provided with: an objective lens 21, an imaging optical system 29b (reference Figure 7 ) is located closest to the subject among the optical components of the optical system; two illumination lenses 22 are used to illuminate the subject; a measurement auxiliary light lens 23 is used to illuminate the subject with the measurement auxiliary light described later; a treatment instrument outlet 24 is used to extend the treatment instrument toward the subject; and an air and water supply nozzle 25 is used to supply air and water. The objective lens 21 constitutes the observation window in the technical solution. The air and water supply nozzle 25 is equivalent to the fluid injection nozzle in the technical solution. The liquid transported by the air and water supply nozzle 25 is cleaning water, and the gases transported are air and carbon dioxide.

[0073] The optical axis LI of the objective lens 21 (reference Figure 6 ) extends in a direction perpendicular to the paper surface. The longitudinal first direction D1 is perpendicular to the optical axis LI, and the lateral second direction D2 is perpendicular to the optical axis LI and the first direction D1.

[0074] like Figure 3 As shown, the light source device 14 includes a light source section 26 and a light source control section 27. The light source section 26 (illumination light source section) generates illumination light for illuminating the subject. The illumination light emitted from the light source section 26 enters the light guide 28 and is irradiated to the subject through the illumination lens 22. As the light source section 26, as a light source of the illumination light, it is preferable to use a white light source that emits white light, or a plurality of light sources including a white light source and a light source that emits light of other colors (for example, a blue light source that emits blue light), etc. The light source control section 27 is connected to the system control section 41 of the processor device 16. The light source control section 27 controls the light source section 26 according to commands from the system control section 41. In addition to issuing commands related to light source control to the light source control section 27, the system control section 41 (light emission control section) also controls the light source 30a (reference) of the measurement auxiliary light emitting section 30. Figure 4 ). Details of the light source control by the system control unit 41 will be described later.

[0075] The distal end portion 12d of the endoscope 12 is provided with an illumination optical system 29a, an imaging optical system 29b, and a measurement auxiliary light emitting unit 30. The illumination optical system 29a includes an illumination lens 22, through which light from the light guide 28 is irradiated onto the observation object. The imaging optical system 29b includes an objective lens 21 and an imaging element 32. Reflected light from the observation object is incident on the imaging element 32 via the objective lens 21. As a result, a reflected image of the observation object is formed on the imaging element 32.

[0076] The imaging element 32 is a color imaging sensor that captures the reflected image of the subject and outputs an image signal. The imaging element 32 is preferably a CCD (Charge Coupled Device) imaging sensor, a CMOS (Complementary Metal-Oxide Semiconductor) imaging sensor, or the like. The imaging element 32 used in the present invention is a color imaging sensor for obtaining RGB image signals of three colors: R (red), G (green), and B (blue). The imaging element 32 is controlled by the imaging control unit 33. Alternatively, a complementary color imaging element provided with color filters of complementary colors: C (blue), M (magenta), Y (yellow), and G (green) can be used as the imaging element 32.

[0077] The image signal output from the imaging element 32 is sent to a CDS / AGC circuit 34. The CDS / AGC circuit 34 performs correlated double sampling (CDS) and automatic gain control (AGC) on the analog image signal. The image signal passed through the CDS / AGC circuit 34 is converted into a digital image signal by an A / D converter (A / D (Analog / Digital) converter) 35. The A / D-converted digital image signal is input to the processor device 16 via a communication interface 36.

[0078] The processor device 16 includes a communication I / F (interface) 38 connected to the communication I / F 36 of the endoscope 12, a signal processing unit 39, a display control unit 40, and a system control unit 41. The communication I / F 38 receives image signals transmitted from the communication I / F 36 of the endoscope 12 and transmits them to the signal processing unit 39. The signal processing unit 39 includes a built-in memory for temporarily storing image signals received from the communication I / F 38. The signal processing unit 39 processes the image signal group (a collection of image signals stored in the memory) to generate a captured image.

[0079] The signal processing unit 39 acquires an image captured by the endoscope. Furthermore, when the signal processing unit 39 is set to length measurement mode, the captured image can be subjected to structural enhancement processing to emphasize structures such as blood vessels, and color difference enhancement processing to enhance the color difference between normal and lesion areas within the observation object.

[0080] The display control unit 40 displays the captured image generated by the signal processing unit 39 on the monitor 18. The system control unit 41 controls the imaging element 32 via the imaging control unit 33 provided in the endoscope 12. The imaging control unit 33 also controls the CDS / AGC circuit 34 and the A / D converter 35 based on the control of the imaging element 32. The still image storage control unit 43 controls the still images of the captured images stored in the still image storage unit 42. The still image storage control unit 43 performs the control described below by issuing a single still image acquisition command in the length measurement mode.

[0081] like Figure 4 As shown, the auxiliary measurement light emitting unit 30 (auxiliary measurement light source unit) includes a light source 30a, a GRIN (Gradient Index) lens 30b, a prism 30c, an optical fiber 30d, and the auxiliary measurement light lens 23. The light source 30a emits light (specifically, visible light) of a color detectable by the pixels of the imaging element 32. It includes a light-emitting element such as a laser diode (LD) or an LED (Light Emitting Diode), and a focusing lens that focuses the light emitted from the light-emitting element. The auxiliary measurement light lens 23 constitutes the auxiliary light illumination window and the auxiliary light illumination window optical component in the technical solution. The auxiliary measurement light lens 23 has a cylindrical shape. When assembled to the distal end portion 12d, the distal end face 23a is a plane perpendicular to the axial direction Z of the insertion portion 12a, and the proximal end face 23b is a plane intersecting the axial direction Z and aligned with the distal end face of the prism 30c.

[0082] The wavelength of light emitted by the light source 30a is preferably, for example, 600 nm to 750 nm, more preferably 600 nm to 700 nm, and most preferably red light of 630 nm to 660 nm. Alternatively, green light of 495 nm to 570 nm may be used. The light source 30a is controlled by the system control unit 41 and emits light according to commands from the system control unit 41.

[0083] The base end side (light source 30a side) of the optical fiber 30d is covered with a fiber jacket 30e, and the front end side (laser emitting side) is inserted into a ferrule 30f and bonded with an adhesive, and the end face is polished.

[0084] The GRIN lens 30b is mounted on the front end of the ferrule 30f, and the prism 30c is mounted on the front end of the GRIN lens 30b to form a joint. The ferrule 30f is a component for holding and connecting the optical fiber 30d. Figure 4 A hole for inserting the optical fiber 30d is penetrated (in the left and right directions).

[0085] A reinforcement material 30g is provided outside the ferrule 30f and fiber housing 30e to protect the optical fiber 30d and other components. The auxiliary measurement light lens 23, GRIN lens 30b, and prism 30c are housed in a housing 30h. The housing 30h is bonded to the reinforcement material 30g. Thus, the auxiliary measurement light lens 23, GRIN lens 30b, prism 30c, and optical fiber 30d are integrally held within the reinforcement material 30g and housing 30h.

[0086] The optical fiber 30d guides the light from the light source 30a to the GRIN lens 30b. The GRIN lens 30b converts the light guided from the light source 30a through the optical fiber 30d into highly coherent light again, thereby converting the light emitted from the light source 30a into measurement auxiliary light for measuring the object.

[0087] The prism 30c is an optical component for changing the direction of the auxiliary measurement light converted by the GRIN lens 30b. The prism 30c changes the direction of the auxiliary measurement light so that it intersects with the field of view of the imaging optical system 29b including the objective lens 21 and the lens group. The details of the direction of the auxiliary measurement light will be described later. The auxiliary measurement light emitted from the prism 30c is irradiated onto the subject through the auxiliary measurement light lens 23. Figure 5 As shown, by irradiating the subject H with the measurement auxiliary light, a light spot SP that is a circular area (specific area) is formed in the subject.

[0088] Alternatively, the auxiliary measurement light lens 23 may be replaced with a measurement-assisting slit formed in the distal end portion 12d of the endoscope. Furthermore, the auxiliary measurement light lens 23 is preferably coated with an anti-reflection coating (AR coating) (anti-reflection portion). The anti-reflection coating is provided because if the auxiliary measurement light is not transmitted through the auxiliary measurement light lens 23 but is reflected, the proportion of the auxiliary measurement light that illuminates the subject is reduced, making it difficult for the signal processing unit 39 to identify the position of the light spot SP formed on the subject by the auxiliary measurement light.

[0089] The auxiliary measurement light emitting unit 30 only needs to be capable of emitting auxiliary measurement light toward the field of view of the imaging optical system. For example, the light source 30a can be provided in a light source device, and the light emitted from the light source 30a can be guided to the GRIN lens 30b via the optical fiber 30d. Alternatively, a configuration can be employed in which, instead of using the prism 30c, a DOE (Diffractive Optical Element) is used in place of the GRIN lens 30b. The light source 30a, the DOE, and the optical fiber guiding the light from the light source 30a to the DOE are tilted relative to the optical axis L1, thereby emitting auxiliary measurement light in a direction that spans the field of view of the imaging optical system.

[0090] Regarding measuring the direction of travel of the auxiliary light, such as Figure 6 As shown, the auxiliary measurement light is emitted with its optical axis LM intersecting the optical axis LI of the objective lens 21. As can be seen, if observation is possible within the observation distance range R1, the position of the spot SP formed on the subject by the auxiliary measurement light within the imaging range (indicated by arrows QN, QM, and QF) differs at each point in the imaging range (indicated by arrows QN, QM, and QF) at the near end PN, near the center PM, and far end PF of range R1 (the point where each arrow QN, QM, and QF intersects the optical axis LM). Furthermore, the imaging optical system's angle of view is indicated by the region between two solid lines 45. Within this angle of view, measurement is performed in the central region (the region between two dashed lines 46), where aberrations are minimal.

[0091] As described above, by emitting auxiliary measurement light with its optical axis LM intersecting with the optical axis LI, the sensitivity to the movement of the light spot position relative to changes in the observation distance is high, enabling highly accurate measurement of the size of the subject. The subject illuminated by the auxiliary measurement light is then captured by the imaging element 32, thereby obtaining an image including the light spot SP.

[0092] The signal processing unit 39 functions as a position determination unit that determines the position of the light spot SP based on the captured image. Specifically, it determines coordinate information related to the position of the light spot SP. The light spot SP appears in the captured image within a roughly circular red area that includes a large number of components corresponding to the color of the auxiliary measurement light. Therefore, the position of the light spot SP is determined within this roughly circular red area. For example, the captured image is binarized and the center of gravity of the white portion (pixels with signal intensities higher than the binarization threshold) in the binarized image is determined as the position of the light spot SP.

[0093] The signal processing unit 39 also functions as an observation distance detection unit that detects the observation distance based on the position of the light spot SP. The signal processing unit 39 detects the observation distance based on the position of the light spot SP by referring to an observation distance table that stores the relationship between the position of the light spot SP in the captured image and the observation distance. Furthermore, coordinate information related to the position of the light spot SP, the observation distance, and the like are preferably stored as attached data to the captured image.

[0094] like Figure 7 As shown, the front end portion 12d includes a front end portion body 51, a front end cover 52, an objective lens 21, and an illumination lens 22 (refer to Figure 8 )、Disposal equipment outlet 24 (reference Figure 8 ), the air and water supply nozzle 25, etc. The front end body 51 is formed of a hard material such as metal, and holds the imaging optical system 29b, the air and water supply nozzle 25, the connecting pipe 53 and the light guide 28 (see Figure 3 )、Disposal instrument insertion tube 54 (reference Figure 8 ) and other components. In addition, Figure 7 In order to prevent the drawing from being complicated, the light guide 28, the treatment instrument insertion tube 54, etc. are omitted.

[0095] The distal end cap 52 is formed of an insulating resin material and covers the distal end side of the distal end body 51 of the insertion portion 12a in the axial direction Z. Hereinafter, the end surface on the distal end side (object side) in the axial direction Z may be referred to as the distal end surface or the distal end, and the end surface on the side opposite to the object side may be referred to as the proximal end surface or the proximal end.

[0096] The front end cover 52 is formed with the objective lens 21, the illumination lens 22, the air and water supply nozzle 25, through holes 52a to 52d for exposing the measurement auxiliary light lens 23, and the treatment instrument outlet 24 (see FIG. Figure 8 The objective lens 21 also serves as the cover glass for the imaging optical system 29b and is located at the very front end of the imaging optical system 29b. The imaging optical system 29b, including the objective lens 21, is held by the lens barrel 55. The lens barrel 55 holds the base end of the outer peripheral surface of the objective lens 21. The distal end of the outer peripheral surface of the objective lens 21 fits into the through-hole 52a of the front end cover 52.

[0097] The lens barrel 55 is held by the front end body 51. The front end surface of the lens barrel 55 abuts against the base end side of the front end cover 52, and the objective lens 21 is configured to be exposed from the front end side of the front end cover 52. In addition, as the objective lens 21, located at the front end side of the imaging optical system 29b, a cover glass without a lens effect can be used. Furthermore, the objective lens 21 does not need to constitute the imaging optical system 29b, and can simply be fixed to the through hole 52d of the front end cover 52 as a cover glass.

[0098] Furthermore, the treatment instrument outlet 24 is connected to the treatment instrument insertion tube 54 inserted into the insertion portion 12a and the treatment instrument introduction port 12f (see FIG. Figure 1 ) is connected to export the treatment instrument inserted from the treatment instrument introduction port 12f.

[0099] The suction tube (not shown) is connected to the treatment instrument insertion tube 54, and the suction button 12g (see FIG. 1 ) is operated by the operation portion 12b. Figure 1 ) and suction is performed from the disposal device outlet 24.

[0100] like Figure 8 As shown, the front end cover 52 is provided with a front end surface 56. The front end surface 56 includes a flat surface 56a, a flat surface 56b, and a guide surface 56c. Flat surface 56a is a plane perpendicular to the axial direction Z. Flat surface 56b is parallel to flat surface 56a and is located further forward than flat surface 56a in the axial direction Z. The guide surface 56c is disposed between flat surface 56a and flat surface 56b.

[0101] The through holes 52a and 52b are arranged on the plane 56b. That is, the front end face 21a of the objective lens 21 and the front end faces 22a of the pair of illumination lenses 22 are arranged on the plane 56b, which are exposed from the through holes 52a and 52b. The objective lens 21 is arranged between the pair of illumination lenses 22. The front end faces 21a of the objective lens 21 and the front end faces 22a of the illumination lenses 22 are flat surfaces and are arranged on the same plane as the plane 56b in the axial direction Z (see also FIG. Figure 7 ).

[0102] The aforementioned through-holes 52c and 52d are arranged on plane 56a. The air and water supply nozzle 25 is exposed from through-hole 52c. Specifically, plane 56a represents the mounting position of the air and water supply nozzle 25 in the axial direction Z. The air and water supply nozzle 25 is connected to the air and liquid supply pipe 57 via the connecting pipe 53. The base end of the air and water supply nozzle 25 is fitted onto one end of the connecting pipe 53, while one end of the air and liquid supply pipe 57 is fitted onto the other end.

[0103] A jetting tube 25a is formed at the distal end of the air and water supply nozzle 25. The jetting tube 25a is cylindrical and projects from the base of the air and water supply nozzle 25 in a direction bent, for example, 90 degrees. It has a jetting port 25b at its distal end. The jetting tube 25a projects from the through-hole 52c toward the distal end in the axial direction Z.

[0104] The jet port 25b of the air and water supply nozzle 25 is arranged toward the objective lens 21. Thus, the air and water supply nozzle 25 sprays the cleaning liquid or gas as a fluid toward the front end surface 21a of the objective lens 21 and its surrounding area.

[0105] The air and water supply nozzle 25 communicates with an air and liquid supply tube 57 inserted into the endoscope 12 , and is connected to an air and water supply device (not shown) connected to the endoscope 12 via the air and liquid supply tube 57 .

[0106] Furthermore, if the air and water supply button 12h (refer to Figure 1 ) is opened, the gas from the air and water supply device is ejected from the air and water supply nozzle 25. If the air and water supply button 12h is pressed with the finger that closes the leakage hole, the cleaning liquid from the air and water supply device is ejected from the air and water supply nozzle 25.

[0107] In addition, as a cleaning step of the objective lens 21, for example, after cleaning liquid is sprayed from the air and water supply nozzle 25 to remove blood, body fluids and other attachments attached to the objective lens 21, gas is sprayed from the air and water supply nozzle 25 to remove the cleaning liquid remaining in the objective lens 21 or its adjacent area.

[0108] like Figure 9 As shown, when cleaning water or gas is sprayed from the air and water supply nozzle 25 toward the objective lens 21, the flow velocity F1 of the cleaning water at the position where it reaches the objective lens 21, i.e., the outer periphery of the objective lens 21, is preferably 2 m / s or more, and the flow velocity F2 of the gas at the outer periphery of the objective lens 21 is preferably 40 m / s or more. Furthermore, the flow velocities F1 and F2 preferably satisfy the above-mentioned values regardless of the orientation of the front end portion 12d. For example, when the air and water supply nozzle 25 is located vertically below the objective lens 21, the flow velocity of the cleaning water or gas decreases due to the influence of gravity. However, in this case, the above-mentioned values are also preferably satisfied.

[0109] The front end face 23a of the auxiliary measurement light lens 23, exposed from the through-hole 52d, is disposed on the plane 56a. That is, the mounting position of the air and water supply nozzle 25 and the front end face 23a of the auxiliary measurement light lens 23 are disposed at the same position in the axial direction Z. The auxiliary measurement light lens 23 is disposed within the fluid ejection range of the air and water supply nozzle 25 and between the objective lens 21 and the air and water supply nozzle 25.

[0110] like Figure 10 As shown, in this embodiment, when the front end face 56 is viewed from the axial direction Z, the auxiliary measurement light lens 23 is disposed in the region connecting the injection port 25b of the air and water supply nozzle 25 and the outer peripheral edge of the objective lens 21. Thus, when fluid is injected from the air and water supply nozzle 25 toward the objective lens 21, fluid can also be injected toward the auxiliary measurement light lens 23 simultaneously.

[0111] Furthermore, in this embodiment, the center axis CA of the lens 23 for measuring the auxiliary light is located on the center line CL of the injection tube 25a, but it is not limited to this. As long as the lens 23 for measuring the auxiliary light is arranged within the fluid injection range of the air and water supply nozzle 25 and between the objective lens 21 and the air and water supply nozzle 25, the position of the center axis CA can be offset from the center line CL.

[0112] It is preferred that the outer diameter d1 of the auxiliary measurement light lens 23 be greater than or equal to 0.5 mm and less than or equal to 1.6 mm, that the minimum distance between the outer edge of the objective lens 21 and the outer edge of the auxiliary measurement light lens 23, i.e., the first minimum distance G1, be greater than or equal to 0 mm and less than or equal to 1.5 mm, and that the minimum distance between the outer edge of the auxiliary measurement light lens 23 and the front end of the air and water supply nozzle 25, i.e., the second minimum distance G2, be greater than or equal to 0 mm and less than or equal to 0.5 mm. By minimizing the first minimum distance G1 and the second minimum distance G2, when the cleaning water or gas ejected from the air and water supply nozzle 25 toward the objective lens 21 reaches the objective lens 21, it is sprayed onto the objective lens 21 while maintaining a sufficient flow rate. Furthermore, the outer diameter d1 of the auxiliary measurement light lens 23 is preferably greater than the outer diameter d2 of the objective lens 21 (reference Figure 11 ) is smaller. In addition, the outer diameter d1 of the auxiliary light lens 23 is preferably larger than the opening width W1 of the air and water supply nozzle 25 (refer to Figure 11 )Small.

[0113] In this embodiment, a guide surface 56c is provided between plane 56a and plane 56b. As described above, plane 56a and plane 56b have a step difference in the axial direction Z, but guide surface 56c is formed by a continuous surface connecting planes 56a and 56b. Specifically, guide surface 56c is an inclined surface that is flat from the position where it contacts the outer edge of the auxiliary measurement light lens 23 to the position where it contacts the outer edge of the objective lens 21.

[0114] The guide surface 56c is positioned within the fluid ejection range of the air and water supply nozzle 25. Therefore, when fluid is ejected from the air and water supply nozzle 25, the fluid is also ejected onto the guide surface 56c. The fluid ejected onto the guide surface 56c diffuses and is then sprayed onto the objective lens 21. Furthermore, in this case, the entire guide surface 56c may be included within the fluid ejection range of the air and water supply nozzle 25, or only a portion of the guide surface 56c may be included. In this embodiment, the entire guide surface 56c is included within the region connecting the ejection port 25b of the air and water supply nozzle 25 and the outer peripheral edge of the objective lens 21.

[0115] like Figure 11 As shown, the opening width W1 of the air and water supply nozzle 25 is smaller than the outer diameter d2 of the objective lens 21. As described above, the guide surface 56c is located within the fluid ejection range of the air and water supply nozzle 25, so the fluid is diffused through the guide surface 56c. As a result, the fluid diffused through the guide surface 56c is sprayed onto the objective lens 21 (by Figure 11 The state indicated by the dotted arrow is thus able to improve the cleaning performance of the objective lens 21 whose outer diameter d2 is larger than the opening width W1 of the air and water supply nozzle 25.

[0116] Assume that there is no guide surface 56c, as shown in FIG. Figure 12 As shown in the comparative example, in the front end portion 120, the fluid ejected from the air and water supply nozzle 125 does not diffuse but instead travels straight ahead and is sprayed onto the objective lens 121. Consequently, the fluid is not ejected onto the objective lens 121, whose outer diameter d12 is larger than the opening width W11 of the air and water supply nozzle 125. Consequently, the fluid is not ejected onto the portions on either side of the fluid ejection range (the hatched portions), potentially leaving dirt. In contrast, the guide surface 56c in this embodiment eliminates this problem.

[0117] The function of the above-described configuration will now be described. When the length measurement mode is set, the system control unit 41 controls the operation of the imaging element 32 via the imaging control unit 33. It also controls the operation of the light source unit 26 of the light source device 14 and the light source 30a of the auxiliary measurement light emitting unit 30, controlling the illumination light and auxiliary measurement light according to a pre-set emission pattern. After the imaging element 32, light source unit 26, and light source 30a begin operating, the insertion unit 12a is inserted into the subject, for example, the digestive tract.

[0118] Light from the light source device 14 passes through the light guide 28 and the illumination lens 22 and is irradiated onto the observed area within the digestive tract. Auxiliary measurement light from the light source 30a passes through the auxiliary measurement light lens 23 and is irradiated onto the observed area. The imaging element 32 captures the interior of the digestive tract and outputs an image signal. This image signal is input to the processor device 16 via the communication I / F 36 and the communication I / F 38 and displayed on the monitor 18. The illumination of the auxiliary measurement light causes a light spot SP to be reflected in the captured image.

[0119] When dirt adheres to the objective lens 21 or the measurement auxiliary light lens 23, the air and water supply button 12h is operated to spray cleaning water from the jet port 25b to clean the objective lens 21. After cleaning the objective lens 21, the air and water supply button 12h is further operated to spray air from the jet port 25b to blow away any cleaning water remaining on the objective lens 21.

[0120] As described above, the auxiliary measurement light lens 23 is positioned within the fluid ejection range of the air and water supply nozzle 25 and between the objective lens 21 and the air and water supply nozzle 25. Therefore, when fluid is ejected from the air and water supply nozzle 25 toward the objective lens 21, it can also be ejected toward the auxiliary measurement light lens 23. This allows the auxiliary measurement light lens 23 to be cleaned simultaneously with the objective lens 21, effectively removing contamination from the auxiliary measurement light lens 23.

[0121] Moreover, when cleaning water or gas is sprayed toward the objective lens 21 from the air and water supply nozzle 25, the flow rate F1 of the cleaning water at the outer periphery of the objective lens 21 is set to be greater than 2 m / s, and the flow rate F2 of the gas at the outer periphery of the objective lens 21 is set to be greater than 40 m / s, so that the fluid is sprayed at a flow rate sufficient to remove dirt from the objective lens 21 while removing dirt from the lens 23 for measuring auxiliary light.

[0122] [Second embodiment]

[0123] In the first embodiment, there is a second minimum distance G2 between the outer edge of the auxiliary measurement light lens 23 and the front end of the air and water supply nozzle 25. However, in the second embodiment, this distance is set to 0 mm, and the auxiliary measurement light lens is brought into contact with the air and water supply nozzle to limit the position of the auxiliary measurement light lens. Figure 13 The distal end portion 60 shown in FIG. 1 has a notch 61a in the auxiliary measurement light lens 61. The notch 61a is located opposite the air and water supply nozzle 25. The structure other than the auxiliary measurement light lens 61 and the through-holes 62a and 62b of the distal end cover 52 is identical to the distal end portion 12d and the auxiliary measurement light emitting portion 30 of the first embodiment described above. The same reference numerals are used and their description will be omitted.

[0124] The notch 61a is formed at a position that avoids the optical path of the auxiliary measurement light emitted from the auxiliary measurement light lens 61. In this embodiment, the notch 61a is located on the opposite side of the optical axis LM2 of the auxiliary measurement light relative to the central axis CA2 of the auxiliary measurement light lens 61. This prevents the outer shape of the spot SP formed on the subject by irradiation with the auxiliary measurement light from being impaired.

[0125] like Figure 14 As shown, similarly to the measurement auxiliary light lens 23 of the above-mentioned first embodiment, the measurement auxiliary light lens 61 is formed in a cylindrical shape, but is different in having a notch portion 61a. The notch portion 61a is an inclined surface inclined from the front end surface 61b of the measurement auxiliary light lens 61 toward the outer peripheral surface 61c. The air supply and water supply nozzle 25 is assembled to the front end portion 60 in a state in which the front end of the injection cylinder portion 25a abuts the notch portion 61a. In addition, similarly to the above-mentioned first embodiment, the air supply and water supply nozzle 25 and the measurement auxiliary light lens 61 are retained on the front end portion main body 51. Moreover, at this time, since the air supply and water supply nozzle 25 is assembled to the front end portion 60 in a state in which the air supply and water supply nozzle 25 abuts the measurement auxiliary light lens 61, the through holes 62a, 62b (refer to Figure 15 ) form a whole.

[0126] In the assembly process of the front end portion 60, for example, Figure 15As shown, after the auxiliary measurement light lens 61 is retained in the front end body 51 along with the prism 30c, the housing 30h, and the like, the air and water supply nozzle 25 is retained in the front end body 51 along with the connecting tube 53. As described above, the air and water supply nozzle 25 is assembled with the ejection tube 25a abutting the notch 61a. Therefore, the ejection tube 25a abutting the notch 61a is located further forward in the axial direction Z than the auxiliary measurement light lens 61. Consequently, the position of the auxiliary measurement light lens 61 in the axial direction Z is restricted.

[0127] As described above, since the air and water supply nozzles 25 restrict the position, the auxiliary measurement light lens 61 can be accurately positioned in the axial direction Z. Furthermore, the air and water supply nozzles 25 restrict the position, thereby preventing the auxiliary measurement light lens 61 from detaching in the axial direction Z. Furthermore, during the assembly process, there is no need to secure the distal end of the auxiliary measurement light lens 61 to the distal end portion body 51 by bonding or the like, thereby reducing the number of assembly steps for the distal end portion 60.

[0128] Furthermore, in the second embodiment, the measuring auxiliary light lens 61 is formed with an inclined surface that is inclined from the front end surface 61b of the measuring auxiliary light lens 61 toward the outer peripheral surface 61c as the notch portion 61a, but this is not limited to this. As long as the notch portion is opposed to the air and water supply nozzle 25 and abuts against the air and water supply nozzle 25 when assembled to the front end portion 60, for example, Figure 16 As shown, the notch 63a may be recessed relative to the front end face 63b of the auxiliary measurement light lens 63 and parallel to the front end face 63b. As a result, the position of the auxiliary measurement light lens 63 in the axial direction Z is restricted, similarly to the second embodiment.

[0129] [Third embodiment]

[0130] In the second embodiment, the position of the auxiliary light lens 61 is restricted by making the auxiliary light lens 61 contact the air and water supply nozzle 25, but in the third embodiment, the position of the auxiliary light lens 61 is restricted by making the auxiliary light lens contact the front end cover. Figure 17 In the distal end portion 65 shown in FIG, similar to the auxiliary measurement light lens 61 of the second embodiment, a notch 66a is provided in the auxiliary measurement light lens 66. The structure other than the auxiliary measurement light lens 66 and the through-holes 67a and 67b of the distal end cover 52 is identical to the distal end portion 12d and the auxiliary measurement light emitting portion 30 of the first embodiment, and thus the same reference numerals are used and their description will be omitted.

[0131] Similar to the notch 61a of the measurement-auxiliary-light lens 61 in the second embodiment, the notch 66a is formed at a position that avoids the optical path of the measurement-auxiliary-light emitted from the measurement-auxiliary-light lens 66. This prevents the outer shape of the spot SP formed on the subject by irradiation with the measurement-auxiliary-light from being impaired.

[0132] like Figure 18 As shown, the notch portion 66a is an inclined surface that is inclined from the front end face 66b of the measurement auxiliary light lens 66 toward the outer peripheral surface 66c. Through holes 67a and 67b are formed in the front end cover 52 to expose the measurement auxiliary light lens 66 and the air and water supply nozzle 25. The measurement auxiliary light lens 66 has a notch portion 66a at a position opposite to the base end side of the front end cover 52. The through hole 67a is a shape that cuts out a part of a circle according to the shape of the front end face 66b. The notch portion 66a of the front end face 66b abuts against the base end side of the front end cover 52 and is exposed from the through hole 67a. In addition, an inclined surface 67c that is inclined corresponding to the notch portion 66a is formed in the through hole 67a (refer to Figure 17 ). As a result, the position of the auxiliary measurement light lens 66 in the axial direction Z is restricted.

[0133] As described above, since the position is restricted by the front end cover 52, the auxiliary measurement light lens 66 can be accurately positioned in the axial direction Z. Furthermore, the position restriction by the front end cover 52 prevents the auxiliary measurement light lens 66 from being dislodged in the axial direction Z. Furthermore, during the assembly process, there is no need to secure the distal end side of the auxiliary measurement light lens 66 to the front end portion body 51 by bonding or the like, thereby reducing the number of assembly steps for the front end portion 65.

[0134] Furthermore, as described above, the through hole 67a is formed in a shape that cuts out a portion of a circle, so that the injection port 25b of the air and water supply nozzle 25 can be arranged close to the front end surface 66b of the auxiliary measurement light lens 66. This allows for more efficient removal of dirt from the auxiliary measurement light lens 66.

[0135] Furthermore, in the third embodiment, the measuring auxiliary light lens 66 is formed with an inclined surface that is inclined from the front end surface 66b toward the outer peripheral surface 66c as the notch portion 66a, but this is not limited to this. As long as it is a notch portion that abuts against the front end cover 52 when assembled to the front end portion 65, for example, the notch portion of the second embodiment can be used. Figure 16 The measurement auxiliary light lens 63 shown in FIG may have a notch portion that is recessed further than the front end surface 66 b and parallel to the front end surface 66 b. Thus, as in the third embodiment described above, the position in the axial direction Z is restricted.

[0136] [Modification]

[0137] The following describes various modifications of the above-mentioned embodiments. In addition, for the same structures as those in the above-mentioned embodiments, the same symbols are used and the description is omitted. In the above-mentioned embodiments, the case of displaying a measuring mark for measuring the size of the observed object, etc. on the camera image is described. Specifically, the display control unit 40 displays the measuring image on the monitor 18 so that the measuring mark is displayed on the subject image according to the position of the light spot SP as the irradiation area. And, specifically, the display control unit 40 displays the measuring image on the monitor 18 with the first measuring mark superimposed on it, with the light spot SP as the center. As the first measuring mark, for example, a circular measuring mark is used. In this case, as Figure 19 As shown, when the observation distance is close to the proximal end PN, a mark M1 representing the actual size of 5 mm (horizontally and vertically of the subject image) is displayed, aligned with the center of the spot SP1 formed on the tumor tm1 of the subject. Furthermore, when displaying measurement marks on the monitor 18, they can also be displayed on the monitor 18 according to the observation distance.

[0138] And, as Figure 20 As shown, when the observation distance is close to the center PM, a mark M2 representing an actual size of 5 mm (in the horizontal and vertical directions of the subject image) is displayed, aligned with the center of the spot SP2 formed on the tumor tm2 of the subject. The mark M2 is displayed at the center of the subject image, which is less susceptible to deformation caused by the objective lens 21. Therefore, the mark M2 is not affected by deformation and has a circular shape.

[0139] And, as Figure 21 As shown, the center of the spot SP3 formed on the tumor tm3 of the subject is aligned, and a mark M3 representing the actual size of 5 mm (horizontally and vertically of the subject image) is displayed. Figures 19 to 21 As shown in FIG. 1 , the size of the first measurement mark corresponding to the same actual size of 5 mm decreases as the observation distance increases. Furthermore, the shape of the first measurement mark also varies depending on the mark display position due to the influence of the deformation caused by the objective lens 21.

[0140] In addition, Figures 19 to 21 In the embodiment, the center of the light spot SP is aligned with the center of the mark and displayed. However, if there is no problem in measurement accuracy, the first measurement mark can be displayed at a position away from the light spot SP. However, in this case, it is also preferable to display the first measurement mark near the light spot.

[0141] And, in Figures 19 to 21In FIG, a first measurement mark corresponding to the actual size of the object, 5 mm, is displayed. However, the actual size of the object can be set to any value (for example, 2 mm, 3 mm, 10 mm, etc.) according to the observation object and the purpose of observation.

[0142] like Figures 19 to 21 As shown, the positional relationship between the measurement mark and the light spot SP is not limited to the light spot SP being located at any one of the "center of gravity", "center" or "coordinates of the visual center" of the measurement mark, and the shape of the measurement mark is not limited to a circle. Figures 22 to 25 As shown, the measurement mark setting unit can set a measurement mark with a scale based on the end portion corresponding to the position of the light spot SP. The end portion refers to the portion closer to the outer portion than the center portion in the shape of the measurement mark, or the starting point or end point.

[0143] Figure 22 The measurement image of the mark M4 set by the measurement mark setting unit is superimposed on the subject image in such a manner that the position of the light spot SP overlaps with the base point of the scale of the mark M4. Figures 22 to 25 In the figure, the tumor tm has a three-dimensional shape, so the subject image includes the tumor tm, the light spot SP, and, if necessary, the shadow SH. For more accurate measurement, the marker M4 is preferably displayed overlapping the position of the light spot SP. Therefore, even when displayed at a position separate from the light spot SP, it is preferably displayed as close to the light spot SP as possible. The marker M4 is a straight line segment, and has a line segment perpendicular to the straight line segment, i.e., a scale, at the start and end points of the line segment. If the marker M4 is a line segment, etc., and has a start and end point, the start and / or end point itself can be used as a scale. In this case, for example, there may be no scale in the shape of a line segment perpendicular to the straight line segment.

[0144] Furthermore, the mark M4 may have the number "10" near the base point of the scale. This is the scale label LA for the mark M4, and is used to easily identify the line segment of the mark M4 as representing an actual size of 10 mm. The numbers used in the measurement markings below have the same meaning. The numerical value of the scale label LA can be changed based on the settings, and the mark M4 may not display the scale label LA itself.

[0145] Various types of measurement markers are used depending on the settings, for example, a straight line segment or a combination of straight line segments, a circle or a combination of circles, or a combination of a straight line segment and a circle.

[0146] For example, Figure 23The measurement image shown in FIG includes a marker M5 formed by combining straight line segments. Marker M5 is formed by combining straight line segments into an L-shape. The segments extend upward and rightward on the paper, starting at the corners of the L-shape and ending at scale marks. Similar to marker M4, marker M5 has the number "10" as a scale label LA near the scale's base point.

[0147] For example, Figure 24 The measurement image shown in FIG includes a mark M6, which is a combination of a straight line segment and a circle. Mark M6 is a combination of a circle and a line segment serving as the circle's diameter. The line segment extends to the right of the page, with one of the intersections of the line segment and the circle as its base point. The intersection of the line segment and the circle serves as a scale mark. A scale mark SC may be provided at the point where the line segment is halved or at the center of the circle. Similarly to marks M4 and M5, mark M6 includes the number "10" as a scale label LA near the base point of the scale mark.

[0148] like Figure 25 As shown, in addition to these, the measurement mark can also be a mark M7A ( Figure 25 (A)), the line segment extending from the base point along the paper downward direction including the mark M7B of the scale label LA ( Figure 25 (B)), or a line segment extending from the base point along the upper right side of the paper, including the mark M7C of the scale label LA ( Figure 25 (C)) and other shapes.

[0149] And, in addition to these, Figure 26 As shown, it can also be set as a cross type with vertical and horizontal lines. In addition, it can also be set as a cross type with a scale Mx added to at least one of the vertical and horizontal lines of the cross type. In addition, as the first measurement mark, it can be set as a distorted cross type in which at least one of the vertical and horizontal lines is tilted. In addition, the first measurement mark can be set as a circle and a cross type formed by combining a cross type and a circle. In addition, the first measurement mark can be set as a measurement point group type formed by combining multiple measurement points EP corresponding to the actual size from the light spot. In addition, the number of the first measurement marks can be one or more, and the color of the first measurement mark can be changed according to the actual size.

[0150] In addition, as the first measurement mark, Figure 27As shown, three concentric circular markers M8A, M8B, and M8C (with diameters of 2 mm, 5 mm, and 10 mm, respectively) of varying sizes can be displayed on the subject image, centered around the spot SP formed on the tumor tm. Displaying multiple markers saves the effort and time of switching between them, and enables measurement even with nonlinear subjects. Furthermore, displaying multiple concentric circular markers centered around the spot allows for selection from multiple pre-prepared combinations of conditions, rather than specifying the size and color of each marker.

[0151] exist Figure 27 In the example, all three concentric circle marks are displayed in the same color (black), but when multiple concentric circle marks are displayed, multiple colored concentric circle marks may be displayed with the colors changing depending on the mark. Figure 28 As shown, the mark M9A is represented by a red dotted line, the mark M9B is represented by a blue solid line, and the mark M9C is represented by a white one-dot chain line. By changing the color of the marks in this way, the recognition is improved, thereby making it possible to easily perform measurement.

[0152] Furthermore, as the first measurement mark, in addition to a plurality of concentric circle marks, such as Figure 29 As shown in FIG, a plurality of distorted concentric circle marks formed by distorting each concentric circle may be used. In this case, the distorted concentric circle marks M10A, M10B, and M10C are displayed in the subject image with the spot SP formed on the tumor tm as the center.

[0153] In the length measurement mode, the illumination light and the focused light (measuring light) are continuously irradiated to the subject. Figure 30 As shown, the illumination light may be continuously on and continuously illuminate the subject, while the spotlight is repeatedly turned on and off (or dimmed) every frame (or every few frames) to intermittently illuminate the subject. In this case, the spotlight position is detected and the measurement mark is set for display during the frames in which the spotlight is on. The measurement mark, which has been set for display, is then preferably displayed superimposed on the image obtained during the frames in which only the illumination light is illuminated.

[0154] In addition, as for the measurement light, light that forms a light spot when irradiated to the subject is used, but other light may be used. Figure 31As shown, linear measurement light can be used that forms a cross line 80 on the subject when irradiated. By irradiating the subject with linear measurement light, cross line 80, which serves as a linear irradiation area, is formed on the subject. In this case, a second measurement mark is generated, consisting of cross line 80 and scale 82. Scale 82 serves as an indicator of the size of the subject (e.g., polyp P) on cross line 80.

[0155] When linear measuring light is used as the measuring light, the illumination light and the linear measuring light may be continuously irradiated onto the subject in the length measurement mode, and Figure 32 As shown, the subject may be continuously illuminated by illumination light, while the subject may be intermittently illuminated by the linear measurement light, repeatedly turning it on and off (or dimming it) every frame (or every few frames). In this case, the position of the linear measurement light is detected and the display of the measurement mark is set during the frames in which the linear measurement light is on. The measurement mark, which has been set for display, is then preferably displayed superimposed on the image obtained during the frames in which only the illumination light is illuminated.

[0156] In addition, the measurement light can be used when irradiating the subject, such as Figure 33 As shown, stripe pattern light ZPL forms a stripe-like pattern on the subject (see, for example, Japanese Patent Application Laid-Open No. 2016-198304). Stripe pattern light ZPL is obtained by irradiating a liquid crystal shutter (not shown) with variable transmittance with a specific laser beam. It is formed by two different vertical stripe patterns that periodically repeat in the horizontal direction: an area that transmits the specific laser beam through the liquid crystal shutter (transmission area) and an area that does not transmit the specific laser beam (non-transmission area). When using stripe pattern light as measurement light, the period of the stripe pattern light changes depending on the distance from the subject. Therefore, the stripe pattern light is irradiated multiple times with the liquid crystal shutter shifting its period or phase. The three-dimensional shape of the subject is measured based on the multiple images obtained by shifting the period or phase.

[0157] For example, the subject is alternately irradiated with a stripe pattern light of phase X, a stripe pattern light of phase Y, and a stripe pattern light of phase Z. The stripe pattern light of phases X, Y, and Z shifts the vertical stripe pattern by 120° (2π / 3) each time. At this time, the three images obtained from each stripe pattern light are used to measure the three-dimensional shape of the subject. For example, Figure 34 As shown, it is preferable to switch the stripe pattern light of phase X, the stripe pattern light of phase Y, and the stripe pattern light of phase Z to illuminate the subject in units of one frame (or units of several frames). In addition, it is preferable that the illumination light continuously illuminates the subject.

[0158] In addition, the measurement light can be used when irradiating the subject, such as Figure 35 As shown, measurement light LPL is formed into a grid-like pattern (see, for example, Japanese Patent Application Laid-Open No. 2017-217215). The three-dimensional shape of the subject is determined based on the deformation of the grid pattern when the measurement light LPL is irradiated onto the subject, requiring accurate detection of the grid pattern. Therefore, the measurement light LPL is not a perfect grid pattern, but rather slightly deformed from the grid shape, such as by a wave pattern, to improve detection accuracy. Furthermore, an S-code is provided in the grid pattern to indicate that the endpoints of the left and right horizontal line segments are continuous. When detecting the grid pattern, not only the pattern itself but also the S-code is detected, thereby improving detection accuracy. Furthermore, the grid pattern can include patterns with regularly arranged vertical and horizontal lines, or patterns with multiple light spots arranged in a grid pattern in both the vertical and horizontal directions.

[0159] When the grid-patterned measuring light LPL is used as the measuring light, the illumination light and the grid-patterned measuring light LPL may be continuously irradiated onto the subject in the length measurement mode, and as shown in FIG. Figure 36 As shown, the subject may be continuously illuminated by illumination light, while the subject may be intermittently illuminated by grid-patterned measurement light LPL by repeatedly turning it on and off (or dimming it) every frame (or every few frames). In this case, the three-dimensional shape of the subject is measured using the grid-patterned measurement light LPL during the frames in which the grid-patterned measurement light LPL is illuminated. The three-dimensional shape measurement results are then preferably displayed superimposed on the image obtained during the frames in which only the illumination light was illuminated.

[0160] In addition, regarding the measurement of light, Figure 37 As shown, a three-dimensional plane light TPL represented by grid lines on a subject image can be used (see, for example, Japanese Patent Publication No. 2017-508529). In this case, the tip portion 12d is moved to align the three-dimensional plane light TPL with the measurement object. Then, when the three-dimensional plane light TPL intersects the measurement object, the distance between the three-dimensional plane light TPL and the subject along the intersection curve CC is calculated through manual processing using a user interface or other automated processing.

[0161] When the three-dimensional plane light TPL is used as the measuring light, the illumination light and the three-dimensional plane light TPL may be continuously irradiated onto the subject in the length measurement mode, and as shown in FIG. Figure 38 As shown, it can also be as follows: the illumination light continuously illuminates the subject, and on the other hand, the three-dimensional plane light TPL is intermittently illuminated to the subject by repeatedly lighting and extinguishing (or dimming) every 1 frame (or every few frames).

[0162] In the above-described embodiments, the hardware configuration of the processing units (processing units) that perform various processes, such as the signal processing unit 39, the display control unit 40, and the system control unit 41, is composed of various processors as described below. These processors include general-purpose processors such as CPUs (Central Processing Units) that execute software (programs) and function as various processing units; GPUs (Graphical Processing Units); FPGAs (Field Programmable Gate Arrays) and other processors whose circuit configurations can be modified after manufacture; PLDs (Programmable Logic Devices); and dedicated circuits (Dedicated Circuits) with circuit configurations specifically designed to perform various processes.

[0163] One processing unit can be composed of one of these various processors, or a combination of two or more processors of the same or different types (for example, a combination of multiple FPGAs, a CPU and an FPGA, or a CPU and a GPU, etc.). In addition, multiple processing units can be composed of one processor. As an example of multiple processing units composed of one processor, first, there is a method in which a processor is composed of a combination of one or more CPUs and software, as represented by computers such as clients and servers, and the processor functions as multiple processing units. Secondly, there is a method in which a processor is used that implements the functions of the entire system including multiple processing units using one IC (Integrated Circuit) chip, as represented by a system on chip (SoC). In this way, as a hardware structure, various processing units are composed of one or more of the above-mentioned various processors.

[0164] Furthermore, more specifically, the hardware configuration of these various processors is a circuit in the form of a combination of circuit elements such as semiconductor elements.

[0165] Explanation of symbols

[0166] 10-Endoscope system, 12-Endoscope, 12a-Insert portion, 12b-Operating portion, 12c-Bending portion, 12d-Front end portion, 12e-Angle knob, 12f-Disposal instrument introduction port, 12g-Suction button, 12h-Air and water supply button, 13a-Mode switching switch, 13b-Freeze switch, 14-Light source device, 16-Processor device, 18-Monitor, 19-User interface, 21-Objective lens, 21a-Front end surface, 22-Illumination lens, 22a-Front end surface, 23-Auxiliary measurement light lens, 23a-Front end surface, 23b-Base end surface, 24-Disposal instrument outlet, 25-Air and water supply nozzle, 25a-Injection cylinder, 25b-Injection port , 26-light source unit, 27-light source control unit, 28-light guide, 29a-illumination optical system, 29b-imaging optical system, 30-measurement auxiliary light output unit, 30a-light source, 30b-GRIN (refractive index distribution type) lens, 30c-prism, 30d-optical fiber, 30e-fiber shell, 30f-ferrule, 30g-reinforcement material, 30h-housing, 32-imaging element, 33-imaging control unit, 34-CDS / AGC circuit, 35-A / D converter, 36-communication I / F (interface), 38-communication I / F (interface), 39-signal processing unit, 40-display control unit, 41-system control unit, 42-still image storage unit, 4 3-still image storage control unit, 45-solid line, 46-dashed line, 51-front end body, 52-front end cover, 52a-through hole, 52b-through hole, 52c-through hole, 52d-through hole, 53-connecting tube, 54-treatment instrument insertion tube, 55-lens barrel, 56-front end surface, 56a-flat surface, 56b-flat surface, 56c-guide surface, 57-air and liquid supply tube, 60-front end, 61-measuring auxiliary light lens, 61a-notch, 61b-front end surface, 61c-outer peripheral surface, 62a-through hole, 62b-through hole, 63-measuring auxiliary light lens, 63a-notch, 63b-front end surface, 65-front end, 66-measuring auxiliary light lens Optical lens, 66a-notch, 66b-front end surface, 66c-outer peripheral surface, 67a-through hole, 67b-through hole, 67c-inclined surface, 80-cross line, 82-scale, 120-front end portion, 121-objective lens, 125-air and water supply nozzle, CA-center axis, CA2-center axis, CL-center line, d1-outer diameter, D1-first direction, d12-outer diameter, d2-outer diameter, D2-second direction, DOE-light source, F1-flow velocity, F2-flow velocity, G1-first minimum distance, G2-second minimum distance, H-object, LD-laser light source, LI-optical axis, LM-optical axis, LM2-optical axis, LPL-grid pattern measurement light,M1, M2, M3, M4, M5, M6, M7A, M7B, M7C, M8A, M8B, M8C, M9A, M9B, M9C, M10A, M10B, M10C - marker, Mx - scale, PF - distal end, PM - near central end, PN - proximal end, QF - arrow, QM - arrow, QN - arrow, R1 - range, SC - scale, SH - shadow, SP, SP1, SP2, SP3 - light spot, tm, tm1, tm2, tm3 - tumor, TPL - three-dimensional plane light, W1, W11 - opening width, Z - axial direction, ZPL - stripe pattern light.

Claims

1. An endoscope comprising: an insertion portion, inserted into the subject; a front end surface, provided at the front end of the insertion portion; an observation window, disposed on the front end surface; a fluid ejection nozzle, disposed on the front end surface and ejecting fluid toward the observation window; two illumination lenses, disposed on the front end surface, for irradiating illumination light to the subject; and an auxiliary light irradiation window, which is arranged on the front end surface and emits measurement auxiliary light for measuring the object, The observation window is arranged between the two lighting lenses. The auxiliary light irradiation window is arranged within the fluid ejection range of the fluid ejection nozzle and between the observation window and the fluid ejection nozzle. The measurement auxiliary light is emitted toward a specific area of the subject in a state in which an optical axis of the measurement auxiliary light intersects an optical axis of the observation window.

2. The endoscope according to claim 1, wherein The fluid jetting nozzle jets liquid or gas as the fluid, When liquid or gas is ejected from the fluid ejection nozzle toward the observation window, the flow velocity of the liquid reaching the observation window is 2 m / s or more, and the flow velocity of the gas reaching the observation window is 40 m / s or more.

3. The endoscope according to claim 1, wherein The auxiliary light irradiation window optical component constituting the auxiliary light irradiation window has a notch at a position facing the fluid ejecting nozzle.

4. The endoscope according to claim 2, wherein: The auxiliary light irradiation window optical component constituting the auxiliary light irradiation window has a notch at a position facing the fluid ejecting nozzle.

5. The endoscope according to claim 3, wherein: The notch is arranged at a position that avoids the optical path of the auxiliary measurement light when the auxiliary measurement light is emitted from the auxiliary light irradiation window.

6. The endoscope according to claim 3, wherein: The fluid ejection nozzle is assembled to the insertion portion in a state of being in contact with the notch portion.

7. The endoscope according to claim 5, wherein: The fluid ejection nozzle is assembled to the insertion portion in a state of being in contact with the notch portion.

8. The endoscope according to claim 6, wherein: The position of the auxiliary light irradiation window in the axial direction of the insertion portion is restricted by the contact between the notch and the fluid ejection nozzle.

9. The endoscope according to claim 1, wherein: The endoscope comprises: a front end body that holds an auxiliary light irradiation window optical component constituting the auxiliary light irradiation window, an imaging optical system including the observation window, and the fluid ejection nozzle; and a front end cover covering the front end side of the front end body, The auxiliary light irradiation window optical component has a notch at a position facing the front end cover.

10. The endoscope according to claim 2, wherein: The endoscope comprises: a front end body that holds an auxiliary light irradiation window optical component constituting the auxiliary light irradiation window, an imaging optical system including the observation window, and the fluid ejection nozzle; and a front end cover covering the front end side of the front end body, The auxiliary light irradiation window optical component has a notch at a position facing the front end cover.

11. The endoscope according to claim 9, wherein: The position of the auxiliary light irradiation window in the axial direction of the insertion portion is restricted by the contact between the notch portion and the front end cover.

12. The endoscope according to any one of claims 3 to 11, wherein: The auxiliary light irradiation window optical component is formed into a cylindrical shape, The notch portion is an inclined surface that is inclined from the front end toward the outer peripheral surface of the optical component for the auxiliary light irradiation window.

13. The endoscope according to any one of claims 1 to 11, wherein: The outer diameter of the auxiliary light irradiation window is greater than or equal to 0.5 mm and less than or equal to 1.6 mm. The minimum distance between the outer edge of the observation window and the outer edge of the auxiliary light irradiation window, i.e., the first minimum distance, is greater than 0 mm and less than 1.5 mm, and the minimum distance between the outer edge of the auxiliary light irradiation window and the front end of the fluid injection nozzle, i.e., the second minimum distance, is greater than 0 mm and less than 0.5 mm.

14. The endoscope according to claim 12, wherein: The outer diameter of the auxiliary light irradiation window is greater than or equal to 0.5 mm and less than or equal to 1.6 mm. The minimum distance between the outer edge of the observation window and the outer edge of the auxiliary light irradiation window, i.e., the first minimum distance, is greater than 0 mm and less than 1.5 mm, and the minimum distance between the outer edge of the auxiliary light irradiation window and the front end of the fluid injection nozzle, i.e., the second minimum distance, is greater than 0 mm and less than 0.5 mm.

15. The endoscope according to any one of claims 1 to 11, wherein: The installation position of the fluid ejection nozzle relative to the front end surface is the same as the position of the front end surface of the auxiliary light irradiation window in the axial direction of the insertion portion. The front end surface of the observation window is located on the front end side in the axial direction relative to the front end surface of the auxiliary light irradiation window. A continuous guide surface is provided between the outer periphery of the auxiliary light irradiation window and the outer periphery of the observation window.

16. The endoscope according to claim 12, wherein: The installation position of the fluid ejection nozzle relative to the front end surface is the same as the position of the front end surface of the auxiliary light irradiation window in the axial direction of the insertion portion. The front end surface of the observation window is located on the front end side in the axial direction relative to the front end surface of the auxiliary light irradiation window. A continuous guide surface is provided between the outer periphery of the auxiliary light irradiation window and the outer periphery of the observation window.

17. The endoscope according to claim 13, wherein: The installation position of the fluid ejection nozzle relative to the front end surface is the same as the position of the front end surface of the auxiliary light irradiation window in the axial direction of the insertion portion. The front end surface of the observation window is located on the front end side in the axial direction relative to the front end surface of the auxiliary light irradiation window. A continuous guide surface is provided between the outer periphery of the auxiliary light irradiation window and the outer periphery of the observation window.

18. The endoscope according to claim 15, wherein The opening width of the fluid ejection nozzle is smaller than the outer diameter of the observation window. The guide surface is located within the fluid ejection range of the fluid ejection nozzle.

19. The endoscope according to any one of claims 1 to 11, wherein: An outer diameter of the auxiliary light irradiation window is smaller than an outer diameter of the observation window.

20. The endoscope according to claim 12, wherein An outer diameter of the auxiliary light irradiation window is smaller than an outer diameter of the observation window.

21. The endoscope according to claim 13, wherein An outer diameter of the auxiliary light irradiation window is smaller than an outer diameter of the observation window.

22. The endoscope according to claim 15, wherein An outer diameter of the auxiliary light irradiation window is smaller than an outer diameter of the observation window.

23. The endoscope according to claim 18, wherein An outer diameter of the auxiliary light irradiation window is smaller than an outer diameter of the observation window.

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