Endoscope system and operating method thereof

Abstract

The invention provides an endoscope system and a method for operating the same, which can calculate the area of a shot object with high recognition accuracy while performing endoscope observation. This endoscope system (10) is provided with an endoscope (11), an air supply device (16), and a processor. The processor controls the emission of illumination light for illuminating a subject (S) and measurement light for measuring the distance between a plurality of sites of the subject (S) and the endoscope (11). In the first air delivery amount, the measurement light is irradiated, and the illumination light is irradiated or extinguished at a light amount suppressed from the measurement light to image the subject (S), and the region of the subject (S) is calculated from the obtained first distance information. In the second air delivery amount, the measurement light is irradiated, and the illumination light is irradiated or extinguished at a light amount suppressed from the measurement light to capture an image of the subject (S), and the region of the subject (S) is calculated from the obtained second distance information.

Description

Technical Field

[0001] The present invention relates to an endoscope system and a working method thereof. Background Art

[0002] In the medical field in recent years, diagnoses using an endoscope system have been widely performed, and there is a method for diagnosing functional diseases of the digestive tract using an endoscope system. Functional diseases of the digestive tract include Functional Dyspepsia (FD) or Irritable Bowel Syndrome (IBS), etc. Compared with healthy individuals, the digestive tract is less likely to expand. By observing the digestive tract and measuring its dilatability, it is possible to support the diagnosis related to functional diseases.

[0003] In the diagnosis of the digestive tract using an endoscope system, various observation methods have been proposed. For example, there is a three-dimensional measurement method in which a measurement light different from the illumination light for illuminating the subject is used to project a pattern onto the subject. The measurement of the dilatability of the digestive tract can be achieved by blowing air from an endoscope equipped with an air supply function into the digestive tract and observing before and after the air supply. As an example of measuring the size of a subject using an endoscope that performs three-dimensional measurement while observing the subject as a diseased part in normal observation, there is the endoscope device of Patent Document 1.

[0004] In the endoscope device of Patent Document 1, there is the following technique: An endoscope having an air supply and water supply nozzle emits measurement auxiliary light to the subject in a specific frame interval with respect to shooting based only on illumination light, shoots the subject, and measures the observation distance of the subject. The size of the subject is measured from the image taken using the measurement auxiliary light.

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2019-187598

[0006] In the measurement of the size of a subject using the measurement auxiliary light of Patent Document 1, in order to emit the measurement auxiliary light together with the illumination light, the mucosal reflection or halo of the illumination light becomes interference, and the recognition accuracy of the pattern light based on the measurement auxiliary light decreases. If the recognition accuracy decreases, the reliability of the measurement result of the size of the subject, especially the change in size, decreases. Summary of the Invention

[0007] An object of the present invention is to provide an endoscope system and a working method thereof that calculate the area of a subject with high recognition accuracy while performing endoscope observation.

[0008] The endoscope system of the present invention includes: an endoscope that captures a subject; a gas supply device connected to the endoscope and supplying gas in multiple stages through the distal end portion of the endoscope; and a processor that performs the following processes: controlling the emission of illumination light for illuminating the subject and measurement light for measuring the distances between multiple parts of the subject and the endoscope; when the gas supply amount is the first gas supply amount, irradiating the measurement light, irradiating or extinguishing the illumination light with a light amount suppressed relative to the measurement light, and obtaining a first imaging signal from the endoscope that has captured the subject; when the gas supply amount is the second gas supply amount at a stage different from the first gas supply amount, irradiating the measurement light, irradiating or extinguishing the illumination light with a suppressed light amount with respect to the measurement light, and obtaining a second imaging signal from the endoscope that has captured the subject; calculating the area of the subject from the first distance information, where the first distance information is obtained by measuring the distances between multiple parts of the subject and the endoscope based on the first imaging signal; and calculating the area of the subject from the second distance information, where the second distance information is obtained by measuring the distances between multiple parts of the subject and the endoscope based on the second imaging signal.

[0009] Preferably, the endoscope performs the following process: capturing the subject by dividing the subject according to each specific angle corresponding to the field of view, and the processor performs the following processes: measuring the first distance information based on multiple first divided imaging signals obtained by capturing the subject according to each specific angle; and measuring the second distance information based on multiple second divided imaging signals obtained by capturing the subject according to each specific angle.

[0010] Preferably, the processor performs the following processes: discriminating a specific part of the subject; calculating the area of the specific part from the first distance information; and calculating the area of the specific part from the second distance information.

[0011] Preferably, the measurement light is a pattern light with dot lights arranged in a grid pattern.

[0012] Preferably, the area is at least any one of a one-dimensional area, i.e., length, a two-dimensional area, i.e., surface area, and a three-dimensional area, i.e., volume.

[0013] Preferably, the endoscope performs the following process:

[0014] applying a light amount threshold, i.e., a light amount threshold, for the emission of the preset measurement light and illumination light; and

[0015] In the case of irradiating the measurement light and irradiating the illumination light with a light amount suppressed relative to the measurement light, performing measurement irradiation in which the measurement light is irradiated with a light amount equal to or greater than the light amount threshold and the illumination light is irradiated with a light amount less than the light amount threshold.

[0016] Preferably, the endoscope performs the following processing: switching between measurement irradiation and observation irradiation that irradiates illumination light with a light quantity equal to or greater than a light quantity threshold to continuously photograph the subject, and the processor performs the following processing: displaying the observation endoscope image generated by photographing the subject through the observation irradiation on a screen.

[0017] Preferably, the endoscope performs the following processing: switching between measurement irradiation and measurement site confirmation irradiation that irradiates illumination light and measurement light with a light quantity equal to or greater than a light quantity threshold to continuously photograph the subject, and the processor performs the following processing: displaying two types of light endoscope images generated by photographing the subject through the measurement site confirmation irradiation on a screen.

[0018] Preferably, the processor performs the following processing: displaying the measurement light image generated by photographing the subject through the measurement irradiation on a screen.

[0019] Preferably, the processor performs the following processing: performing different screen displays for each type of the generated images.

[0020] Preferably, the endoscope performs the following processing: switching between measurement irradiation, observation irradiation that irradiates illumination light with a light quantity equal to or greater than a light quantity threshold, and measurement site confirmation irradiation that irradiates illumination light and measurement light with a light quantity equal to or greater than a light quantity threshold to continuously photograph the subject, and the processor performs the following processing: displaying the observation endoscope image generated by photographing the subject through the observation irradiation and the two types of light endoscope images generated by photographing the subject through the measurement site confirmation irradiation on different screens.

[0021] The endoscope system of the present invention includes: an endoscope that photographs a subject; an air supply device that is connected to the endoscope and supplies air in multiple stages through the front end portion of the endoscope; and a processor that performs the following processing: controlling the emission of illumination light for illuminating the subject and measurement light for measuring the distances between multiple parts of the subject and the endoscope; when the air supply volume is a first air supply volume, irradiating the measurement light, irradiating or extinguishing the illumination light with a light quantity suppressed relative to the measurement light, and obtaining a first imaging signal from the endoscope that has photographed the subject; when the air supply volume is a second air supply volume at a stage different from the first air supply volume, irradiating the measurement light, irradiating or extinguishing the illumination light with a light quantity suppressed relative to the measurement light, and obtaining a second imaging signal from the endoscope that has photographed the subject; calculating an index value representing the stretching amount of the subject using first distance information obtained by measuring the distances between multiple parts of the subject and the endoscope based on the first imaging signal and second distance information obtained by measuring the distances between multiple parts of the subject and the endoscope based on the second imaging signal and outputting the index value.

[0022] Preferably, the processor performs the following processing: calculating the volume of the subject based on the index value.

[0023] The method of operating the endoscope system of the present invention includes the following steps: The air supply device supplies air in multiple stages through the distal end portion of the endoscope that photographs the subject; controls the emission of illumination light for illuminating the subject and measurement light for measuring the distance between multiple parts of the subject and the endoscope; when the air supply volume is the first air supply volume, irradiates the measurement light, irradiates or extinguishes the illumination light with a light amount suppressed relative to the measurement light, and obtains a first imaging signal from the endoscope that has photographed the subject; when the air supply volume is the second air supply volume at a stage different from the first air supply volume, irradiates the measurement light, irradiates or extinguishes the illumination light with a light amount suppressed relative to the measurement light, and obtains a second imaging signal from the endoscope that has photographed the subject; calculates the area of the subject from the first distance information, where the first distance information is obtained by measuring the distance between multiple parts of the subject and the endoscope based on the first imaging signal; and calculates the area of the subject from the second distance information, where the second distance information is obtained by measuring the distance between multiple parts of the subject and the endoscope based on the second imaging signal.

[0024] Advantages of the Invention

[0025] According to the present invention, it is possible to calculate the area of the subject with high recognition accuracy while performing endoscope observation. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a schematic diagram of the endoscope system.

[0027] Figure 2 is an explanatory diagram of observing the distal end portion of the endoscope from the front.

[0028] Figure 3 is a block diagram showing the functions of the endoscope system.

[0029] Figure 4 is an explanatory diagram of a method of expanding the stomach by supplying air to the pressure balloon.

[0030] Figure 5 is an explanatory diagram of a method of expanding the stomach by supplying air using the endoscope.

[0031] Figure 6 is an explanatory diagram of an endoscope for observing while supplying air.

[0032] Figure 7 is an explanatory diagram of (A) a measurement light image photographed with measurement light, (B) an observation endoscope image photographed with illumination light, and (C) a two-light endoscope image photographed with measurement light and illumination light obtained during observation in the measurement mode.

[0033] Figure 8 is an explanatory diagram showing the relationship between the internal pressure and volume of the gastric fundus in healthy subjects and patients with gastrointestinal functional diseases.

[0034] Figure 9 It is an explanatory diagram for determining a specific part in the subject.

[0035] Figure 10 It is an explanatory diagram for photographing the subject through the first observation pattern.

[0036] Figure 11 It is an explanatory diagram for photographing the subject through the second observation pattern.

[0037] Figure 12 It is an explanatory diagram for photographing the subject through the third observation pattern.

[0038] Figure 13 It is an explanatory diagram for photographing the subject through the fourth observation pattern.

[0039] Figure 14 It is an explanatory diagram for photographing the subject through the fifth observation pattern.

[0040] Figure 15 It is an explanatory diagram for photographing the subject through the sixth observation pattern.

[0041] Figure 16 It is an explanatory diagram for photographing the subject through the seventh observation pattern.

[0042] Figure 17 It is an explanatory diagram of the projection pattern based on the measurement light.

[0043] Figure 18 It is a flowchart showing a series of processes of the three-dimensional measurement of the present invention.

[0044] Figure 19 It is an explanatory diagram of the light source device in the modification example.

[0045] Figure 20 It is an explanatory diagram of the projection pattern based on the measurement light in the modification example.

[0046] Symbol Explanation

[0047] 10 - Endoscope system, 11 - Endoscope, 11a - Insertion section, 11b - Operation section, 11c - Bending section, 11d - Tip section, 11e - Mode switch, 11f - Air supply switch, 11g - Body forceps port, 12 - Light source device, 13 - Processor device, 14 - Display, 15 - User interface, 16 - Air supply device, 17 - Manometer, 21 - Illumination lens, 22 - Objective lens, 23 - Measurement light emission section, 24 - Air supply nozzle, 25 - Tip forceps port, 30 - Light source for illumination, 32 - Light source for measurement, 32a - First measurement light source, 32b - Second measurement light source, 32c - Third measurement light source, 34 - Light emission control section, 36 - Light guide, 38 - Illumination optical system, 40 - Imaging optical system, 44 - Imaging sensor, 45 - Imaging control section, 46 - CDS / AGC circuit, 48 - A / D converter, 50 - Image signal acquisition section, 51 - DSP, 52 - Noise reduction section, 53 - Image processing section, 54 - Output control section, 60 - Distance measurement processing section, 62 - Distance measurement section, 64 - Specific part discrimination section, 66 - Region calculation section, 68 - Air supply control section, 70 - Measurement light image, 72 - Observation endoscope image, 74 - Two - light endoscope image, 76 - Health curve, 78 - Functional disease curve, 80 - Measurement light pattern, 80a - Green light projection part, 80b - Red light projection part, 80c - Blue light projection part, 82 - Specific part, Ax - Rotation axis, BS - Balloon, D - Digestive tract, H - Viewpoint, P0 - Reference internal pressure value, P1 - Internal pressure value, P2 - Internal pressure value, R - Imaging range, S - Subject, ST110 to ST200 - Steps, V0 - Reference volume value, V1 - Volume value, W - Volume width. Detailed implementation mode

[0048] As Figure 1 As shown, the endoscope system 10 of the embodiment of the present invention includes an endoscope 11, a light source device 12, a processor device 13, a display 14, a user interface (UI) 15, an air supply device 16, and a manometer 17. The endoscope 11 is optically connected to the light source device 12 and electrically connected to the processor device 13. The light source device 12 supplies illumination light to the endoscope 11. Further, the endoscope 11 is physically connected to the air supply device 16 and the manometer 17. The air supply device 16 supplies the measurement gas to the endoscope 11.

[0049] The endoscope 11 illuminates illumination light and captures a subject to obtain an endoscopic image. The endoscope 11 has an insertion portion 11a inserted into a subject such as the digestive tract and an operation portion 11b provided at the proximal end portion of the insertion portion 11a. A bending portion 11c and a distal end portion 11d are provided on the front end side of the insertion portion 11a. The bending portion 11c performs a bending operation in a desired direction by being operated by the operation portion 11b. The distal end portion 11d irradiates illumination light toward the subject and receives reflected light from the subject to capture the subject. A mode changeover switch 11e for switching operations of a mode and a gas supply switch 11f for controlling the gas supply from the gas supply device 16 are provided on the operation portion 11b.

[0050] The processor device 13 is electrically connected to the display 14 and the user interface 15. The processor device 13 receives an image signal from the endoscope 11 and performs various processes based on the image signal. An external recording portion (not shown) for recording images, image information, etc. can be connected to the processor device 13. The display 14 outputs and displays an image of the captured subject or image information, etc. that has been subjected to image processing by the processor device 13. The user interface 15 has a keyboard, a mouse, a touchpad, a microphone, a foot pedal, etc., and has a function of receiving input operations such as function settings.

[0051] As Figure 2 shown, when viewed from the front, the distal end portion 11d of the endoscope 11 is substantially circular, and is provided with an illumination lens 21 for irradiating illumination light supplied from the light source device 12, an objective lens 22 for receiving light from the subject, a measurement light output portion 23 for emitting measurement light supplied from the light source device 12 in an arbitrary pattern, a gas supply nozzle 24 for supplying a measurement gas supplied from the gas supply device 16, and a distal end portion forceps port 25 connected to the main body portion forceps port 11g through a forceps channel. Also, the measurement light output portion 23 can be used separately from the endoscope 11. In this case, it has the function of the measurement light output portion 23, and emits measurement light based on a probe that can enter and exit through the forceps port.

[0052] The gas supply device 16 supplies a measurement gas to the endoscope 11 according to the pressing of the gas supply switch 11f. The measurement gas is supplied into the living body from the gas supply nozzle 24 via a gas supply channel passing through the inside of the endoscope 11. The measurement gas is, for example, carbon dioxide gas or air, and the digestive tract is inflated by the gas supply. Also, the gas supply device 16 can be electrically connected to the processor device 13 to set a gas supply pattern for controlling the gas supply timing, gas supply output, etc., and automatically perform gas supply. Also, the gas supply output, that is, the gas supply volume per unit time, is controlled. In the absence of a specific designation, gas supply is performed at an arbitrary fixed output.

[0053] The pressure gauge 17 measures the pressure of the gas transmitted through the hose connected to the forceps port 11g of the main body. The transmitted gas passes through the forceps channel inside the insertion portion 11a from the distal end forceps port 25 to the main body forceps port 11g. When the distal end portion 11d of the endoscope 11 is inserted into a specific digestive tract, the pressure gauge 17 can measure the internal pressure of the specific digestive tract. According to the amount of measurement gas sent into the digestive tract and the state of the specific digestive tract, the pressure transmitted to the pressure gauge 17 changes. In addition, the pressure gauge 17 is electrically connected to the processor device 13 and sends the measured internal pressure information to the processor device 13 at any time.

[0054] As Figure 3 shown, in the endoscope system 10, the light source device 12 propagates the emitted illumination light to the endoscope 11 via the light guide 36. The endoscope 11 sends the image signal captured using the illumination light to the processor device 13, and the processor device 13 generates an image to be displayed on the display 14.

[0055] The light source device 12 includes: an illumination light source 30 that emits a plurality of illumination lights or white light, i.e., illumination light, with different main wavelengths; a measurement light source 32 that emits a measurement light with a wavelength different from that of the illumination light source 30 and is used for measurement; and a light emission control unit 34 that controls the light emission timing, light emission amount, etc. of the illumination light source 30 and the measurement light source 32. The measurement light source 32 is preferably a laser light source. Also, the measurement light source 32 can be implemented in modes such as in the case of the illumination light source 30, in the case of the endoscope 11, and in other devices such as a measurement light source device different from the light source device 12.

[0056] The function of the light emission control unit 34 is realized by a light source control processor (not shown) provided in the light source device 12, and controls the illumination light emitted by the illumination light source 30 and the measurement light emitted by the measurement light source 32. In addition, when the light source device 12 is electrically connected to the processor device 13, the function of the light source control processor can also be realized by the central control unit instead of the light source control processor. The light emission control unit 34 adjusts the drive current according to a preset light emission pattern.

[0057] The illumination light and the measurement light are incident on the light guide 36. The light guide 36 is built into the endoscope 11 and the general cord (the cord connecting the endoscope 11 to the light source device 12 and the processor device 13). The light guide 36 propagates the light from the light source device 12 to the distal end portion 11d of the endoscope 11.

[0058] The illumination optical system 38 and the imaging optical system 40 are provided at the front end portion 11d. The illumination light propagated through the light guide 36 is irradiated onto the subject via the illumination lens 21 included in the illumination optical system 38. Also, the measurement light propagated through the light guide 36 is irradiated onto the subject via the measurement light exit portion 23 included in the illumination optical system 38. The imaging optical system 40 includes an objective lens 42 and an imaging sensor 44. The reflected light of the illumination light and the measurement light returning from the subject is incident on the imaging sensor 44 via the objective lens 42. Thus, an image of the subject is formed on the imaging sensor 44 which is a color imaging sensor.

[0059] In the measurement light, a pattern for measuring distances at multiple sites at once and obtaining distance information is irradiated onto the subject. For example, the measurement light is a pattern light arranged in a grid pattern in which the shape of a point light is repeated in an arbitrary pattern.

[0060] The imaging control unit 45 drives and controls the imaging sensor 44 based on the mode changeover switch 11e, or an instruction via the user interface 15 of the processor device 13, and a signal from the light emission control unit 34, and controls the mode change of the observation mode and the imaging in each mode. In the control of imaging, adjustment of the exposure period based on the setting of the shutter speed in the electronic shutter (not shown) of the imaging sensor 44 is performed.

[0061] When there is no special specification, the length of the imaging frame of the imaging sensor 44 is constant, and thus it is controlled to alternately repeat the accumulation period and the read period at a predetermined time interval, for example, 60 fps (frames per second), that is, at an interval of 1 / 60 second. The shutter speed of the electronic shutter can also be changed and the length of the imaging frame can be adjusted.

[0062] As the imaging sensor 44, a photoelectric conversion element such as a CCD (Charge Coupled Device) sensor or a CMOS (Complementary Metal - Oxide Semiconductor) sensor is used. In the imaging sensor 44, for example, within the acquisition period of one frame, the received light is photoelectrically converted, and the accumulation operation of accumulating signal charges corresponding to the amount of received light for each pixel and the read operation of reading the stored signal charges are performed. The signal charges of each pixel read out from the imaging sensor 44 are converted into voltage signals and input to the CDS / AGC (Correlated Double Sampling / Automatic Gain Control) circuit 46. The light source device 12 generates illumination light corresponding to the timing of the accumulation operation of the imaging sensor 44 and makes it incident on the light guide 36.

[0063] In each pixel of the imaging sensor 44, there is provided any one of a B pixel (blue pixel) having a B (blue) color filter, a G pixel (green pixel) having a G (green) color filter, and an R pixel (red pixel) having an R (red) color filter. For example, the imaging sensor 44 is preferably a color imaging sensor with a Bayer arrangement in which the ratio of the number of pixels of the B pixel, G pixel, and R pixel is 1:2:1.

[0064] The B color filter mainly transmits light in the blue band, specifically, light with a wavelength band of 380 to 560 nm (blue transmission band). The peak wavelength with the maximum transmittance exists near 460 to 470 nm. The G color filter mainly transmits light in the green band, specifically, light with a wavelength band of 450 to 630 nm (green transmission band). The R color filter mainly transmits light in the red band, specifically, light with a wavelength band of 580 to 760 nm (red transmission band).

[0065] Also, instead of the primary color imaging sensor 44, a complementary color imaging sensor equipped with complementary color filters of C (cyan), M (magenta), Y (yellow), and G (green) can be used. When using the complementary color imaging sensor, image signals of four colors, CMYG, are output. Therefore, through complementary color-primary color conversion, the image signals of four colors, CMYG, are converted into image signals of three colors, RGB, so that image signals of each RGB color identical to those of the imaging sensor 44 can be obtained.

[0066] The CDS / AGC circuit 46 performs correlated double sampling (CDS) or automatic gain control (AGC) on the analog image signal obtained from the imaging sensor 44. The image signal passing through the CDS / AGC circuit 46 is converted into a digital image signal by an A / D (Analog / Digital) converter 48. The digital image signal after A / D conversion is input to the processor device 13.

[0067] In the processor device 13, programs related to each process are embedded in a program memory (not shown). A central control unit (not shown) composed of a processor executes the programs in the program memory, thereby implementing the functions of an image signal acquisition unit 50, a DSP (Digital Signal Processor) 51, a noise reduction unit 52, an image processing unit 53, and an output control unit 54.

[0068] The image signal acquisition unit 50 receives the image signal input from the endoscope 11 driven and controlled by the imaging control unit 45, and sends the received image signal to the DSP 51. The output control unit 54 sends the image signal of the displayed image obtained from the image processing unit 53 to the display 14.

[0069] The DSP51 performs various signal processes on the received image signal, such as defect correction process, offset process, gain correction process, linear matrix process, gamma conversion process, demosaicing process, and YC conversion process. In the defect correction process, the signal of the defective pixels of the imaging sensor 44 is corrected. In the offset process, the dark current component is removed from the image signal that has undergone the defect correction process, and the correct zero level is set. The gain correction process adjusts the signal level of each image signal by multiplying the image signals of each color after the offset process by a specific gain. The linear matrix process for improving color reproducibility is performed on the image signals of each color after the gain correction process.

[0070] Then, the brightness or chroma of each image signal is adjusted through the gamma conversion process. The demosaicing process (also called isotropic process, synchronization process) is performed on the image signal after the linear matrix process, and the signal of the missing color of each pixel is generated by interpolation. Through the demosaicing process, all pixels have signals of RGB each color. The DSP51 performs the YC conversion process on the image signals of each color after the demosaicing process, and outputs the luminance signal Y, the color difference signal Cb, and the color difference signal Cr to the noise reduction unit 52.

[0071] The noise reduction unit 52 performs noise reduction processing on the image signal that has undergone the demosaicing process and other processes by the DSP51, such as based on the moving average method and the median filtering method. The image signal with reduced noise is input to the image processing unit 53.

[0072] The image processing unit 53 further performs color conversion processes such as 3×3 matrix processing, grayscale transformation processing, and three-dimensional LUT (Look Up Table) processing on the input image signal of one frame amount. Then, various color enhancement processes are performed on the RGB image data after the color conversion process. The structure enhancement process such as spatial frequency enhancement is performed on the RGB image data after the color emphasis process. In the image processing unit 53, the RGB image data that has undergone the structure enhancement process is output as an image to the output control unit 54 or the distance measurement processing unit 60. The RGB image data may be output to another device that at least has the function of the distance measurement processing unit 60 described later, which is different from the processor device 13, instead of the distance measurement processing unit 60.

[0073] The output control unit 54 sequentially acquires the measurement light image, the observation endoscope image, or the two-light endoscope image, and converts them into a video signal that can be full-color displayed on the display 14. The converted video signal is output and displayed on the display 14. Thus, doctors and the like can observe the subject using the still image or dynamic image of the observation endoscope image.

[0074] The distance measurement processing unit 60 performs distance measurement (ranging) on the subject using the measurement light image, the observation endoscope image, or the dual-light endoscope image obtained by the image processing unit 53, and calculates the surface area or volume of the subject based on the measured distance information. The distance measurement processing unit 60 has the functions of a distance measurement unit 62, a specific part determination unit 64, a region calculation unit 66, and an air supply control unit 68.

[0075] The distance measurement unit 62 performs distance measurement in the image obtained by imaging using the measurement light. Distance information between the front end 11d and the subject with respect to the measurement position corresponding to the projection pattern of the measurement light is obtained.

[0076] The specific part determination unit 64 is the part for which the region calculation is to be performed, and determines the range of the specific part in the image. In the specific part determination, image recognition is performed using the pixel information of the image captured with the illumination light.

[0077] In the image recognition, it can be implemented using a learned model that is optimal for the recognition processing in the image. In this case, the specific part determination unit 64 includes an identifier (not shown) having the learned model required for the image recognition. The identifier includes a computer algorithm CNN (Convolutional Neural Network) composed of a neural network that performs machine learning. The specific part determination unit 64 learns by including data such as an image of the pre-determined object, i.e., the specific part, and an image group including images that do not include the specific part, determines the specific part of the input image, and outputs the position information of the specific part in the input image.

[0078] Moreover, in the specific part determination, when distance information is obtained at the measurement position where the image captured with the measurement light can estimate the number and position of the subject shape, the three-dimensional shape of the captured subject can be estimated, and the specific part can be discriminated by performing estimated shape discrimination based on the characteristics of the estimated shape.

[0079] The region calculation unit 66 calculates the region of the subject using the measured distance information. The region is calculated in association with the time series when the imaging signal is obtained or the information of the air supply volume, and the progress amount of the region of the same part in the subject is obtained. The progress amount calculates and outputs an index value based on the expansion rate of the region, etc. The region calculation unit 66 calculates at least any one of the one-dimensional region, i.e., the length, the two-dimensional region, i.e., the surface area, and the three-dimensional region, i.e., the volume, as the region.

[0080] The area is a value calculated from the measured value of the surface area of a specific part. For example, the surface area or volume of the stomach is calculated based on the surface area of the fornix. Therefore, when measuring the fornix at a specific part, a table for calculating the volume of the stomach from the size ratio between the fornix and the stomach or the surface area of the fornix is stored in advance. When measuring the length as the area, the elongation amount is obtained from the change in the length of the fornix.

[0081] The air supply control unit 68 controls the air supply corresponding to the observation of the subject by the endoscope 11. The air supply is controlled step by step according to the elapsed time, the internal pressure information, or the user operation. Also, the air supply can be automatically suppressed when no increase in the volume of the digestive tract is observed for the air supply. For example, electrically connected to the pressure gauge 17, when the increase in the internal pressure relative to the air supply volume is large, control such as reducing or maintaining the air supply volume is performed.

[0082] As Figure 4 shown, in the method for measuring the changes in the internal pressure and volume of the digestive tract implemented for the diagnosis of existing diseases, there is a pressure control method. In the pressure control method, the patient swallows the balloon BS with a tube, and through the air supply via the tube, as shown by the arrow, the internal pressure of the uniformly inflated balloon BS is used to extrude the digestive tract D, causing the upper part of the stomach, etc. to expand in the arrow direction. The volume of the balloon BS is obtained using the air supply volume and the internal pressure. On the other hand, in the pressure control method, it is difficult to use dedicated equipment, the pain of the patient based on the balloon BS, and the grasping of the position of the balloon BS. It has high invasiveness and the digestive tract cannot be directly observed. Therefore, by using a method of directly supplying air to the digestive tract D without using a balloon to expand it, the burden on the patient can be reduced.

[0083] As Figure 5 shown, the endoscope 11 connected to the air supply device 16 inserts the insertion part 11a into the digestive tract D and supplies air from the air supply nozzle 24. Through the imaging during the air supply, the process of the digestive tract D expanding in the arrow direction or the observation of the digestive tract D at an arbitrary internal pressure can be performed. The internal pressure is measured by the pressure of the gas transmitted from the front-end forceps port 25 to the pressure gauge 17. Since the digestive tract D expands due to the supply of the measurement gas, medical devices such as the endoscope 11 can measure the internal pressure of the digestive tract, as well as the changes in the volume or surface area of the digestive tract D with low invasiveness without contacting the subject.

[0084] Regarding the observation of the digestive tract for measuring the internal pressure and area of the digestive tract using the endoscope system 10, the description will be given using the stomach that expands by air supply as the subject S for observation and measurement, and the fornix as the specific part.

[0085] The endoscope system 10 of the present embodiment continuously lights the illumination light, and arbitrarily switches between a normal observation mode for normal observation and a measurement mode in which lighting and extinguishing operations of two lights with different wavelengths, i.e., the illumination light and the measurement light, are repeated in units of frames to perform distance measurement or volume calculation of the subject for observation. The observation mode is switched by a user operation such as pressing the mode switch 11e.

[0086] As Figure 6 shown, the endoscope 11 is used to observe the subject S in the digestive tract D. The subject S captured by the imaging range R is captured as an endoscope image. When the subject, such as at a specific site, has an insufficient imaging range for one endoscope image over a wide range relative to the imaging range R, or when accurately grasping the three-dimensional structure of the subject S, etc., the bending portion 11c is rotated in the insertion portion 11a inserted into the subject, and the subject S is divided at each specific angle corresponding to the field of view for imaging. For example, the bending portion 11c is rotated along the rotation axis Ax set based on an arbitrary viewpoint H, and endoscope images of the fields of view corresponding to the number of divisions or viewing angles are captured. The rotation axis Ax is arbitrarily set according to the positional relationship between the distal end portion 11d and the specific site or the shape of the specific site.

[0087] Sometimes, the bending of the bending portion 11c is used to rotate the rotation axis Ax of the distal end portion 11d, which is the shooting position set based on an arbitrary viewpoint H with respect to the subject S, so as to perform 360-degree shooting. In this case, for an endoscope 11 with a field of view angle of 120 degrees or more, an endoscope image capable of observing the 360-degree subject S can be obtained by a split imaging signal that divides the field of view into three parts of 120 degrees set at each specific angle. And when the field of view angle is 90 degrees or more and 120 degrees or less, an endoscope image obtained by dividing the field of view into four parts of 90 degrees set at each specific angle can be captured. Split imaging signals that are close in shooting timing, such as within 3 seconds, and are obtained continuously or at specific intervals can be synthesized to produce an endoscope image of the subject S that has been shot over a range wider than the imaging range R.

[0088] In the normal observation mode, an endoscope image obtained by irradiating illumination light suitable for observing the subject S is generated and displayed on the screen. During normal observation, the illumination light is continuously lit during the observation period, and the exposure period is adjusted by opening and closing the shutter, etc. In the normal observation mode, the digestive tract inflated by arbitrarily output air supply can be observed.

[0089] In the measurement mode, the air supply device 16 connected to the endoscope 11 for photographing the subject supplies air in multiple stages from the distal end portion 11d, and controls the emission of the illumination light for illuminating the subject S and the measurement light for measuring the distances between multiple parts of the subject S and the endoscope 11 to capture an endoscope image.

[0090] The air supply volume in multiple stages is the total amount of gas supplied to the digestive tract at any time in a state where the air supply output is fixed at an arbitrary output. For example, if the time interval from the start of air supply is set to 5 seconds in the measurement mode, the air supply volume at the time point 5 seconds after the start of air supply is set as the first air supply volume, and the air supply volume at the time point 10 seconds after the start of air supply is set as the second air supply volume. Similarly, imaging can be performed at the third air supply volume at the time point 15 seconds after the start, and the fourth air supply volume at the time point 20 seconds after the start. Moreover, the measurement time points do not need to be equally spaced. By measuring at a minute time point at the start of dilation, the dilation speed can be measured more accurately.

[0091] As Figure 7 shown, in the measurement mode, as endoscopic images, a measurement light image 70 for calculating the distance and volume of the subject S, an observation endoscopic image 72 for observing the subject S, and a two-light endoscopic image 74 for confirming and observing the measurement part of the subject S are acquired. By irradiating the measurement light, a measurement light pattern 80 is projected onto the subject S. Figure 7 (A) is a measurement light image 70 generated by the processor device 13 by imaging the subject S with a first irradiation that irradiates the measurement light based on the endoscope 11 and irradiates or extinguishes the illumination light with a light amount suppressed relative to the measurement light. Regarding the measurement light, a projection pattern in which a dot pattern is repeated at equal intervals is used to illustrate the measurement light, but a line pattern, a cross pattern, etc. can also be arbitrarily set. Also, the pattern interval does not need to be equally spaced. Figure 7 In (B), the subject S is imaged with a second irradiation that irradiates the illumination light based on the endoscope 11, and an observation endoscopic image 72 generated by the processor device 13 is generated and used to observe the subject. As Figure 7 shown in (C), the subject S is imaged with a third irradiation that irradiates the illumination light and the measurement light based on the endoscope 11, and a two-light endoscopic image 74 generated by the processor device 13 is generated and used for confirmation of the measurement part and observation of the subject S.

[0092] The light amount of the suppressed illumination light is a light amount that does not interfere with the distance measurement based on the measurement light, and is controlled according to a preset threshold value. Thereby, in the measurement light image 70, the position or shape of the subject imaged while preventing interference with the measurement part caused by the mucosal reflected light or diffraction of the measurement light by the illumination light can be confirmed.

[0093] In the measurement mode, the emission of illumination light and measurement light is controlled for imaging. Also, the air supply is controlled while emitting light. In the first irradiation, at least the imaging signals, i.e., the first imaging signal and the second imaging signal, are acquired at multiple different stages of the air supply volume. That is, the air supply device 16 acquires the first imaging signal obtained by irradiating the measurement light and imaging the subject S while suppressing the light quantity irradiation or extinguishing the illumination light with respect to the measurement light in a state where the air is supplied at an arbitrary stage of the air supply volume, i.e., the first air supply volume. Further, in a state where the air supply device 16 supplies air at a second air supply volume different from the first air supply volume, the second imaging signal obtained by irradiating the measurement light and imaging the subject S while irradiating or extinguishing the illumination light with a light quantity suppressed with respect to the measurement light is acquired.

[0094] The first imaging signal and the second imaging signal are used to image the subject S using the measurement light pattern 80 capable of obtaining distance information of multiple measurement parts in the subject S. The area of the subject S is calculated based on the first distance information obtained by measuring the distance between multiple parts of the subject S and the endoscope 11 according to the first imaging signal, and the area of the subject S is calculated based on the second distance information obtained by measuring the distance between multiple parts of the subject S and the endoscope 11 according to the second imaging signal. In the area, there are a one-dimensional area as a length, a two-dimensional area as a surface area, and a three-dimensional area as a volume, and both are calculated to obtain the dilatability of the digestive tract. Further, the first distance information and the second distance information are distance information of a specific part at the same position with respect to different air supply volumes.

[0095] In the measurement mode, distance measurement is performed separately for multiple divided imaging signals obtained by imaging the subject S by dividing it at each specific angle corresponding to the field of view. Under the imaging condition where the field of view within the imaging range R is 120 degrees or more, the bending part 11c is rotated to acquire divided imaging signals divided into 3 at every 120 degrees, and distance measurement is performed according to the 3 divided imaging signals respectively. Also, under the imaging condition where the divided imaging signals obtained by dividing the field of view into 4 parts at every 90 degrees are acquired, distance measurement is performed in the same manner. The specific range determination described later can be implemented according to each divided imaging signal, or can be implemented after integrating the distance information obtained from the divided imaging signals.

[0096] In the first air supply volume, the first distance information is measured based on multiple first divided imaging signals obtained by imaging the subject S at each specific angle. In the second air supply volume, the second distance information is measured based on multiple second divided imaging signals obtained by imaging the subject S at each specific angle. Further, regarding the division, the number of divisions or whether to perform division is determined according to the imaging conditions of the subject S that change according to the air supply volume.

[0097] Patients with diseases in the functions of the digestive tract sometimes exhibit symptoms such as difficulty in expanding the digestive tract, such as the fundus of the stomach, compared to healthy individuals with healthy digestive tract functions. Specifically, the upper limit value of the volume of the stomach increased by an increase in internal pressure is small, and the rate of increase in volume relative to the increase in internal pressure is slow. As Figure 8 shown, the following can be expected: The presence or absence of abnormalities in the functions of the digestive tract is determined using the relationship between the volume and internal pressure of the digestive tract. Through the relationship between the changes in internal pressure and volume in the fundus of the stomach of healthy individuals, the differences in the healthy curve 76 and the functional disease curve 78, which represents the relationship between the changes in internal pressure and volume in the fundus of the stomach of patients with functional dyspepsia, can be revealed.

[0098] When the digestive tract is inflated from the reference internal pressure value P0 and reference volume value V0 in the non-inflated state of the digestive tract, for example, by insufflation, in the functional disease curve 78, the increase in volume stops at the volume value V1 when the internal pressure value is P1. On the other hand, in the healthy curve 76, the volume will increase even if the internal pressure rises further than the internal pressure value P1. And, in the functional disease curve 78, the volume value V1 at which the increase in volume stops is achieved at a pressure lower than the internal pressure value P1, that is, the internal pressure value P2, in the healthy curve 76.

[0099] In addition, when the increase in volume relative to the increase in internal pressure value is absent or very small, the patient will feel pain. Therefore, when the rate of increase in volume relative to internal pressure calculated using the volume observed by insufflation is below a preset ratio, it is preferable to end the insufflation or reduce the amount of insufflation. The volume width W is obtained by comparing the volume differences between the two curves at the same internal pressure. Not limited to the volume width W, by comparing the functional disease curve 78, which represents the relationship between the volume and internal pressure obtained by measurement, with the healthy curve 76, which represents the relationship between the volume and internal pressure of the fundus of the stomach of generally measured healthy individuals, it helps to grasp the state of the functional disease.

[0100] As Figure 9 shown, the specific part discrimination unit 64 discriminates a specific part in the photographed subject S as a specific range 82 using illumination light. When the specific part is the fundus, for example, the area occupied by the fundus is discriminated for the specific range 82 by image recognition of the observation endoscope image 72 using an identifier. The discriminated area is associated with the observation endoscope image 72 in terms of position information, etc. as specific range information. The specific range information is applied to the observation endoscope image 72 used in the discrimination and the measurement light image 70 of the frames before and after the imaging timing. The measurement light image 70 uses the distance information of the measurement part included in the specific range 82. When the fundus is photographed by dividing a plurality of images taken under the same imaging conditions, the segmentation imaging images are used to detect the specific range and discriminate the specific part.

[0101] Further, in the measurement light image 70, when a lattice-shaped measurement light pattern or the like is projected onto the entire image and the measurement area has a high density relative to the image, the three-dimensional shape of the subject S can also be calculated based on the distance information to determine the dome part. Additionally, when the projection range of the measurement light pattern is limited or the density of the measurement area is small relative to the image, the measurement light image 70 with illumination based on the suppressed illumination light or the two-light endoscope images 74 can be used to detect a specific range 82. In this case, as the area of the pattern light, the area not used for measurement or the influence caused by the measurement light is reduced by relatively decreasing the weighted addition in image recognition.

[0102] In the measurement mode, the change in the area of a specific part is measured based on the difference in the distance information obtained at multiple air supply volume stages, and the elongation amount, i.e., the progress amount, of the subject S is calculated. The difference between the first distance information and the second distance information obtained at at least two stages, i.e., the first and second air supply volume stages, is used. The air supply volume stage set when calculating the progress amount (e.g., the air supply volume stage corresponding to the time series) can calculate an index value representing the change rate of the observed distance in the time series. When divided by the internal pressure, an index value representing the change rate of the area in the change of the internal pressure can be calculated. When the subject expands, the observed distance represented by the distance information of the measurement part at the same position becomes longer.

[0103] The air supply volume stages include an initial stage where the air supply volume is negligible immediately after starting the air supply or when there is no air supply, an expansion stage where the subject expands while the air supply volume increases, and an upper limit stage where the main internal pressure rises after the air supply volume exceeds a specified amount and the expansion of the subject almost stops. In the comparison with the healthy state, the air supply volume also uses at least the area of the specific part in the upper limit stage. The measurement interval during imaging is preferably determined based on the time series or the internal pressure.

[0104] In the calculation of the progress amount, at least two stages where the subject expands are used, for example, the areas of the specific parts in the initial stage and the upper limit stage are used. For example, when the air supply volume in the initial stage is set as the first air supply volume and the air supply volume in the upper limit stage is set as the second air supply volume, the minimum distance information of the subject S is calculated based on the first distance information, and the maximum distance information of the subject S is calculated based on the second distance information. Thus, the maximum expansion amount of the subject S can be obtained. The area of the subject S calculated based on the index value is at least one of the surface area or the volume. Additionally, the difference between the average distance in the first distance information and the average distance in the second distance information can also be calculated and used as an index value representing the maximum development amount.

[0105] Further, by measuring the distance information at equally spaced air supply amounts arbitrarily set in the inflation stage and measuring the internal pressure at each air supply amount, the volume of the subject S is calculated, so that an index value representing the progress amount of the time series of the subject can be obtained.

[0106] Further, by using the pressure gauge 17 and setting the first air supply amount, the second air supply amount, and the n-th air supply amount according to the equally spaced change of the internal pressure, distance information corresponding to the internal pressure can be obtained, and it can be calculated as an index value representing the progress amount between arbitrary internal pressures.

[0107] In the measurement mode, distance measurement is performed by the active stereo method that uses actively emitted measurement light for three-dimensional measurement. In the active stereo method, there is a method that utilizes the principle of projection of measurement light and triangulation based on a camera. Further, it may be combined with the lidar method that measures the time difference or phase difference of the measurement light using a TOF (Time of Flight) sensor for measurement. For example, in the active stereo method, the camera function of the endoscope 11 is used to observe the projected measurement light, but the TOF sensor provided in the measurement light emitting unit 23 or the tool inserted into the forceps port is used to observe the measurement light. In the case of using the TOF sensor by inserting it into the forceps port, a method that does not obstruct the pressure measurement, such as using the endoscope 11 having a plurality of forceps ports, is adopted.

[0108] Extraction of the spot light, which is the return light of the measurement light in the measurement light image 70, is performed by binarization processing based on comparison of the light amount with a specified threshold value. The specified threshold value is, for example, a preset extraction threshold value that is applied to the illumination light and the return light of the measurement light in relation to lightness or brightness. In the case of emitting light with a light amount suppressed relative to the measurement light, the measurement light emits light such that the return light becomes a light amount equal to or greater than the extraction threshold value extracted in the binarization processing, and the suppressed illumination light becomes a light amount such that the return light is less than the extraction threshold value not extracted in the binarization processing, and the measurement light image 70 is obtained.

[0109] Therefore, the light emission control unit 34 transmits to the endoscope 11 a light quantity that applies a light quantity threshold value, which is a preset light quantity in the light emission of the measurement light and the suppressed illumination light. In the endoscope 11, the measurement light is irradiated, and in the measurement irradiation in which the illumination light is irradiated with a light quantity suppressed relative to the measurement light, the measurement light is irradiated with a light quantity equal to or greater than the light quantity threshold value and the illumination light is irradiated with a light quantity less than the light quantity threshold value. For example, in a binarization process using 256 gray levels such as "0" to "255", the gray level value of "128" is set as the extraction threshold value, the measurement light emits light with a light quantity such that the returned light becomes a gray level value of "128" or more, and the suppressed illumination light emits light with a light quantity such that the returned light is less than the gray level value of "128". In addition, when only the measurement light is emitted, control is performed to emit a light quantity such that the returned light of the measurement light becomes a light quantity equal to or greater than the extraction threshold value. The light quantity threshold value is set to a value obtained by adding errors such as attenuation in the returned light to the extraction threshold value. The light quantity of the emitted light is the integrated light quantity per unit area.

[0110] Moreover, in order to reduce the error based on the returned light and perform the binarization process more reliably, the measurement light can emit light with a light quantity higher than the ratio specified by the threshold value, and the suppressed illumination light can emit light with a light quantity lower than the ratio specified by the threshold value. For example, the measurement light is controlled to emit light such that the brightness value of "254", which is 2% higher than the threshold value, becomes the average brightness value, and the suppressed illumination light is controlled to emit light such that the brightness value of "102", which is 2% lower than the threshold value, becomes the average brightness value.

[0111] Distance measurement is performed based on the brightness of each measurement part extracted by the extraction process of the measurement light image 70. For example, when there are 256 gradations, distance measurement of the subject S of each measurement part relative to the endoscope is performed at 128 stages among the brightness positions of "128" to "255" extracted. The distance information of each measurement part obtained by the distance measurement is associated with the measurement light image 70.

[0112] In the endoscope observation performed simultaneously with the air supply control, preferably, multiple observation patterns are selectively used. Observation frames based on at least any one of the measurement light image 70, the observation endoscope image 72, and the two-light endoscope image 74 are switched and acquired, and volume measurement and image display are performed. For example, the 1st to 7th observation patterns are switched.

[0113] As Figure 10 shown, in the 1st observation pattern, the measurement light image 70 and the observation endoscope image 72 are switched and acquired at an arbitrary ratio, and the measurement light image 70 and the observation endoscope image 72 are switched and displayed on the display 14. Moreover, area calculations such as distance measurement and volume calculation are performed from the acquired measurement light image 70.

[0114] As Figure 11As shown, in the second observation pattern, the measurement light image 70 and two types of optical endoscope images 74 are switched at an arbitrary ratio and acquired, and the measurement light image 70 and the two types of optical endoscope images 74 are switched and displayed on the display 14. Moreover, area calculations such as distance measurement and volume calculation are performed on the acquired measurement light image 70.

[0115] As Figure 12 shown, in the third observation pattern, the measurement light image 70 and the observation endoscope image 72 are switched at an arbitrary ratio and acquired, and the observation endoscope image 72 is continuously displayed on the screen. The measurement light image 70 for performing area calculations such as distance measurement and volume calculation is not displayed on the screen, so the screen does not flicker.

[0116] As Figure 13 shown, in the fourth observation pattern, the measurement light image 70 and two types of optical endoscope images 74 are switched at an arbitrary ratio and acquired, and the two types of optical endoscope images 74 are continuously displayed on the display 14. The measurement light image 70 for performing area calculations such as distance measurement and volume calculation is not displayed on the screen, so the screen does not flicker.

[0117] As Figure 14 shown, in the fifth observation pattern, the measurement light image 70 and the observation endoscope image 72 are switched at an arbitrary ratio and acquired, and the measurement light image 70 and the observation endoscope image 72 are continuously displayed in two screens respectively. For example, the observation endoscope image 72 is displayed on the first screen, and the measurement light image 70 is displayed on the second screen. Moreover, area calculations such as distance measurement and volume calculation are performed on the measurement light image 70 displayed on the second screen.

[0118] The display of the two screens can be achieved by electrically connecting a second display (not shown) different from the display 14 to the processor device 13 and implementing the first screen and the second screen on their respective displays, or by splitting the screen of the display 14 into two to implement the first screen and the second screen. Moreover, the distance measurement in each frame of the measurement light image 70 displayed on the second screen can be performed after the screen display switches to the next frame, or during the display of the second screen.

[0119] As Figure 15 shown, in the sixth observation pattern, the measurement light image 70 taken by measurement illumination and two types of optical endoscope images 74 are switched at an arbitrary ratio and acquired, and the measurement light image 70 and the two types of optical endoscope images 74 are continuously displayed on two screens respectively. By the same method as in the fifth observation pattern, two-screen display, area calculations such as distance measurement and volume calculation are also performed in the sixth observation pattern.

[0120] In the first to sixth observation patterns, acquisition of the endoscopic image 72 for observation or the two optical endoscopic images 74 for two frames and the measurement light image 70 for one frame is alternately performed. However, it is not limited thereto, and they may be alternately photographed with the same number of frames for each other, and the continuous shooting numbers of the endoscopic image 72 for observation or the two optical endoscopic images 74 and the measurement light image 70 may be arbitrarily set separately and alternately photographed.

[0121] In the third to sixth observation patterns, the endoscopic image 72 for observation or the two optical endoscopic images 74 may be displayed on the screen corresponding to the shooting frame rate, but the frame rate for screen display may also be adjusted corresponding to the shooting ratio. For example, when the ratio of the endoscopic image 72 for observation or the two optical endoscopic images 74 to the measurement light image 70 is 2:1 and shooting is performed at a frame rate of 60 fps, the endoscopic image 72 for observation or the two optical endoscopic images 74 are displayed on the screen at 40 fps. Also, the display of the measurement light image 70 in the fifth to sixth observation patterns may be adjusted corresponding to the shooting ratio.

[0122] As Figure 16 shown, in the seventh observation pattern, the measurement light image 70 photographed by measurement irradiation, the endoscopic image 72 for observation photographed by observation irradiation, and the two optical endoscopic images 74 photographed by measurement site confirmation irradiation are switched and acquired at an arbitrary ratio, and the generated endoscopic image 72 for observation and the two optical endoscopic images 74 are displayed in two screens. In the seventh observation pattern, illumination light is always irradiated with a light amount equal to or more than a specified amount for image display, and the measurement site can be confirmed.

[0123] Each observation pattern may be preset to be switchable by a user operation during the examination. For example, it may be switched by further pressing the mode switch 11e for switching the observation mode, or may be switched by pressing an observation pattern switch (not shown) provided in the endoscope 11 or the user interface 15. Also, the observation patterns may be divided into a shooting pattern for acquiring each imaging signal and a display pattern for controlling the display of each acquired imaging signal, and may be set to be switchable to an arbitrary combination of the shooting pattern and the display pattern.

[0124] As Figure 17 shown, as the projection pattern of the shape when projecting by measurement light, a lattice-shaped dot pattern may be replaced by an arbitrary setting. For example, in addition to the dot pattern, there are a line pattern, a cross pattern, a stripe pattern, a scale pattern, and a combined pattern, etc., and the shapes of projection points or lines may be projected in an arbitrary number or configuration. When using a line, in addition to a solid line, a dotted line or a dashed line is preferably used. For example, when arranging multiple lines for projection, a method of repeating a solid line and a dotted line is used.

[0125] In a dot pattern, as Figure 7 shown in (A), dots or small circles are projected onto the subject S. Distance measurement is performed at the position (light spot) of each point that serves as measurement light. Similar to a line pattern and a cross pattern, it is also possible to distinguish between the shapes of multiple lines that intersect and those that do not intersect according to the subject S and use them accordingly.

[0126] Moreover, there are types such as a single type, a repeating type, a circular type, a center point type, or a special type in which each shape is projected asymmetrically or randomly, or a projection that does not apply to any of them. In volumetric measurement, it is necessary to obtain multiple distance information. Therefore, in the single type, it is necessary to correlate multiple measurement images 71. Therefore, it is preferable to use a projection pattern that sets multiple measurement parts for one measurement light image.

[0127] Along Figure 18 the flowchart shown, a series of processes of the three-dimensional measurement operation of the subject based on the measurement mode in the endoscope system 10 will be described. The insertion portion 11a of the endoscope 11 is inserted into the digestive tract that serves as the subject (step ST110). The endoscope system 10 sets the observation mode to the measurement mode by a user operation on any one of the endoscope 11, the light source device 12, or the processor device 13 (step ST120). In response to the start of the measurement mode such as the switching based on the observation mode, the air supply based on an arbitrary air supply output such as a preset air supply output is started (step ST130). Simultaneously with the start of the air supply, imaging of the subject based on an arbitrary observation pattern is performed (step ST140).

[0128] In any observation pattern, measurement light is irradiated and a measurement light image 70 is obtained by imaging the subject with the light quantity of the illumination light suppressed or extinguished relative to the measurement light (step ST150). Discrimination of a specific part as the observation part is performed from at least any one of the measurement light image 70, the observation endoscope image 72, and the two-light endoscope image 74 (step ST160). Multiple part distance measurements are performed based on the point light projected onto the specific part of the measurement light image 70 (step ST170). Based on the distance measurement results of the specific part, a two-dimensional area or a three-dimensional area of the specific part is calculated (step ST180).

[0129] In the measurement mode, the air supply volume of the subject S at multiple stages is observed, and the area of the specific part is observed. When the area of the specific part in the air supply volumes at multiple stages is calculated (yes in step ST190), the progress amount of the digestive tract is calculated using multiple distance information (step ST200). When the area of the specific part in the air supply volumes at multiple stages is not calculated (no in step ST190), imaging is performed at different air supply volumes at multiple stages, and a measurement light image 70 is obtained (step ST150).

[0130] After calculating the progress amount of the digestive tract, switch from the measurement mode to the normal observation mode to end a series of processes. Alternatively, without switching to the normal observation mode, the endoscopic observation can be directly ended.

[0131] As an example, the light source device 12 having the measurement light source 32 that emits the measurement light as pattern light has been described. However, a light source device 12 that emits measurement light of multiple colors can also be used. For example, a measurement mode in a light source device 12 having three measurement light sources that emit light in different wavelength bands can be implemented. Hereinafter, a projection pattern of measurement light using three measurement light sources as a modification example will be described. Regarding the content other than the measurement light, it is the same as that in the above embodiment, and thus the description is omitted.

[0132] As Figure 19 shown, in the case of using three measurement light sources that emit light of different wavelengths, for example, the light source device 12 includes a first measurement light source 32a that emits green light as the first measurement light, a second measurement light source 32b that emits red light as the second measurement light, and a third measurement light source 32c that emits blue light as the third measurement light. The light emission control unit 34 independently transmits drive currents for controlling the light amount, extinguishing timing, etc. to the illumination light source 30, the first measurement light source 32a, the second measurement light source 32b, and the third measurement light source 32c in the measurement light source 32.

[0133] As Figure 20 shown, in the projection pattern based on multiple measurement lights, it is distinguished according to components such as single points, lines, and stripe patterns, and different measurement lights are projected onto the subject. In the projection pattern composed of two measurement lights based on the first measurement light and the second measurement light, vertical lines are projected onto the green light projection portion 80a based on the first measurement light in the cross pattern, and horizontal lines are projected onto the red light projection portion 80b based on the second measurement light. And in the stripe pattern, odd-numbered segments such as the first segment or the third segment from the top are projected with the green light projection portion 80a, and even-numbered segments such as the second segment are projected with the red light projection portion 80b.

[0134] In the projection pattern composed of three measurement lights based on the first measurement light, the second measurement light, and the third measurement light, in the dot pattern, the leftmost single point is sequentially projected with the green light projection portion 80a based on the first measurement light, the red light projection portion 80b based on the second measurement light, and the blue light projection portion 80c based on the third measurement light. And even in the stripe pattern, it is similarly projected from the left with the green light projection portion 80a, the red light projection portion 80b, and the blue light projection portion 80c.

[0135] The measurement lights of wavelengths different from each other are not limited to three, and four or more light sources can also be used. Further, the shape of the projected pattern of light emission or the method of color separation is also preferably changed appropriately according to the use.

[0136] In the above-described embodiment, the hardware structure of the processing unit (processing unit) that executes various processes of the light emission control unit 34, the imaging control unit 45, the image signal acquisition unit 50, the DSP 51, the noise reduction unit 52, the image processing unit 53, the output control unit 54, and the distance measurement processing unit 60 is various processors (processor) as described below. The various processors include a general-purpose processor that executes software (program) and functions as various processing units, that is, a CPU (Central Processing Unit), a GPU (Graphical Processing Unit), an FPGA (Field Programmable Gate Array), etc., which are programmable logic devices (Programmable Logic Device) that can change the circuit structure after manufacturing, and a processor with a circuit structure specifically designed to execute various processes, that is, an application-specific circuit, etc.

[0137] One processing unit may be constituted by one of these various processors, or may be constituted by a combination of two or more processors of the same type or different types (for example, multiple FPGAs, a combination of a CPU and an FPGA, or a combination of a CPU and a GPU, etc.). Further, multiple processing units may be constituted by one processor. As an example of constituting multiple processing units by one processor, first, there is a method in which, typified by a computer such as a client or a server, one processor is constituted by a combination of one or more CPUs and software, and this processor functions as multiple processing units. Second, there is a method in which, typified by a system on chip (System On Chip: SoC), etc., a processor that realizes the functions of the entire system including multiple processing units by one IC (Integrated Circuit / integrated circuit) chip is used. Thus, the various processing units are constituted by using one or more of the above-described various processors as the hardware structure.

[0138] Moreover, more specifically, the hardware structure of these various processors is a circuit (Circuitry) in a form in which circuit elements such as semiconductor elements are combined. Further, the hardware structure of the storage unit is a storage device such as an HDD (Hard Disc Drive) or an SSD (Solid State Drive). Further, according to the above description, the endoscope system described in Supplementary Notes 1 to 13 below can be grasped.

[0139] [Supplementary Note 1]

[0140] An endoscope system, comprising:

[0141] An endoscope for photographing a subject;

[0142] An air supply device connected to the endoscope and supplying air in multiple stages through the distal end portion of the endoscope; and

[0143] A processor,

[0144] The processor performs the following processes:

[0145] Controlling the emission of illumination light for illuminating the subject and measurement light for measuring the distances between multiple parts of the subject and the endoscope;

[0146] When the air supply volume is the first air supply volume, irradiating the measurement light, irradiating or extinguishing the illumination light with a light amount suppressed relative to the measurement light, and acquiring a first imaging signal from the endoscope that has photographed the subject;

[0147] When the air supply volume is the second air supply volume at a stage different from the first air supply volume, irradiating the measurement light, irradiating or extinguishing the illumination light with a light amount suppressed relative to the measurement light, and acquiring a second imaging signal from the endoscope that has photographed the subject;

[0148] Calculating a region of the subject from first distance information obtained by measuring the distances between multiple parts of the subject and the endoscope based on the first imaging signal; and

[0149] Calculating a region of the subject from second distance information obtained by measuring the distances between multiple parts of the subject and the endoscope based on the second imaging signal.

[0150] [Supplementary Note 2]

[0151] The endoscope system according to Supplementary Note 1, wherein

[0152] The endoscope performs the following processes:

[0153] Photographing the subject by dividing it according to each specific angle corresponding to the field of view,

[0154] The processor performs the following processes:

[0155] Determining the first distance information based on multiple first segmented imaging signals obtained by photographing the subject according to each of the specific angles; and

[0156] The second distance information is measured based on a plurality of second divided imaging signals obtained by imaging the subject at each of the specific angles.

[0157] [Supplementary Note 3]

[0158] The endoscope system according to Supplementary Note 1 or 2, wherein

[0159] The processor performs the following processes:

[0160] Discriminate a specific part of the subject;

[0161] Calculate the area of the specific part from the first distance information; and

[0162] Calculate the area of the specific part from the second distance information.

[0163] [Supplementary Note 4]

[0164] The endoscope system according to any one of Supplementary Notes 1 to 3, wherein

[0165] The measurement light is pattern light in which point lights are arranged in a lattice.

[0166] [Supplementary Note 5]

[0167] The endoscope system according to any one of Supplementary Notes 1 to 4, wherein

[0168] The area is at least any one of a one-dimensional area, i.e., length, a two-dimensional area, i.e., surface area, and a three-dimensional area, i.e., volume.

[0169] [Supplementary Note 6]

[0170] The endoscope system according to any one of Supplementary Notes 1 to 5, wherein

[0171] The endoscope performs the following processes:

[0172] Apply a threshold value of the amount of light, i.e., a light amount threshold, in the emission of the measurement light and the illumination light that is preset; and

[0173] In the case of irradiating the measurement light and irradiating the illumination light with an amount of light suppressed relative to the measurement light, perform measurement irradiation in which the measurement light is irradiated with an amount of light equal to or greater than the light amount threshold and the illumination light is irradiated with an amount of light less than the light amount threshold.

[0174] [Supplementary Note 7]

[0175] The endoscope system according to Supplementary Note 6, wherein

[0176] The endoscope performs the following processes:

[0177] Switch the irradiation for measurement and the irradiation for observation that irradiates the illumination light with a light quantity above the light quantity threshold to continuously photograph the subject.

[0178] The processor performs the following processing:

[0179] Display the endoscopic image for observation generated by photographing the subject through the irradiation for observation on a screen.

[0180] [Supplementary Note 8]

[0181] According to the endoscopic system described in Supplementary Note 6, wherein

[0182] The endoscope performs the following processing:

[0183] Switch the irradiation for measurement and the irradiation for confirmation of the measurement site that irradiates the illumination light and the measurement light with a light quantity above the light quantity threshold to continuously photograph the subject.

[0184] The processor performs the following processing:

[0185] Display the two types of endoscopic images generated by photographing the subject through the irradiation for confirmation of the measurement site on a screen.

[0186] [Supplementary Note 9]

[0187] According to the endoscopic system described in Supplementary Note 7 or 8, wherein

[0188] The processor performs the following processing:

[0189] Display the measurement light image generated by photographing the subject through the irradiation for measurement on a screen.

[0190] [Supplementary Note 10]

[0191] According to the endoscopic system described in Supplementary Note 9, wherein

[0192] The processor performs the following processing:

[0193] Perform different screen displays for each type of the generated images.

[0194] [Supplementary Note 11]

[0195] According to the endoscopic system described in Supplementary Note 6, wherein

[0196] The endoscope performs the following processing:

[0197] Switch the irradiation for measurement, the observation irradiation that irradiates the illumination light with a light quantity above the light quantity threshold, and the measurement site confirmation irradiation that irradiates the illumination light and the measurement light with a light quantity above the light quantity threshold, and continuously photograph the subject.

[0198] The processor performs the following processing:

[0199] Display the observation endoscope image generated by photographing the subject through the observation irradiation and the two light endoscope images generated by photographing the subject through the measurement site confirmation irradiation on different screens.

[0200] [Appendix 12]

[0201] An endoscope system, comprising:

[0202] An endoscope that photographs a subject;

[0203] An air supply device connected to the endoscope and supplying air from the front end of the endoscope in multiple stages of air supply amounts; and

[0204] A processor,

[0205] The processor performs the following processing:

[0206] Control the emission of the illumination light for illuminating the subject and the measurement light for measuring the distance between the subject and the endoscope;

[0207] In a state where the air supply device supplies air at a first air supply amount, irradiate the measurement light, irradiate or extinguish the illumination light with a light quantity suppressed relative to the measurement light, and obtain a first imaging signal from the endoscope that has photographed the subject;

[0208] In a state where the air supply device supplies air at a second air supply amount, which is a stage different from the first air supply amount, irradiate the measurement light, irradiate or extinguish the illumination light with a light quantity suppressed relative to the measurement light, and obtain a second imaging signal from the endoscope that has photographed the subject; and

[0209] Calculate an index value representing the stretching amount of the subject using the difference between the first distance information obtained by measuring the distances between multiple parts of the subject and the endoscope based on the first imaging signal and the second distance information obtained by measuring the distances between multiple parts of the subject and the endoscope based on the second imaging signal, and output the index value.

[0210] [Appendix 13]

[0211] According to the endoscope system described in Appendix 12, wherein,

[0212] The processor performs the following processing:

[0213] Calculate the volume of the subject based on the index value.

Claims

1. An endoscope system comprising: Endoscope, to photograph the subject; an air supply device connected to the endoscope and performing air supply at multiple stages of air supply volumes via the front end portion of the endoscope; and processor, The processor performs the following processing: controlling the emission of illumination light for illuminating a subject and measurement light for measuring distances between a plurality of parts of the subject and the endoscope; When the air supply amount is a first air supply amount, irradiating the measurement light, irradiating or extinguishing the illumination light with a light amount suppressed relative to the measurement light, and acquiring a first imaging signal from the endoscope that images the subject; When the air supply amount is a second air supply amount at a stage different from the first air supply amount, irradiating the measuring light, irradiating or extinguishing the illumination light at a light amount suppressed relative to the measuring light, and acquiring a second imaging signal from the endoscope that images the subject; calculating the area of ​​the object from first distance information obtained by measuring distances between a plurality of parts of the object and the endoscope based on the first imaging signal; and The region of the object is calculated from second distance information obtained by measuring distances between a plurality of sites of the object and the endoscope based on the second imaging signal.

2. The endoscope system according to claim 1, wherein: The endoscope performs the following processing: The subject is divided into sections for photographing at each specific angle corresponding to the field of view, The processor performs the following processing: measuring the first distance information based on a plurality of first divided imaging signals obtained by imaging the object at each of the specific angles; and The second distance information is measured based on a plurality of second divided imaging signals obtained by imaging the subject at each of the specific angles.

3. The endoscope system according to claim 1, wherein: The processor performs the following processing: Identifying a specific part of the subject; calculating the area of ​​the specific part from the first distance information; and The area of ​​the specific part is calculated based on the second distance information.

4. The endoscope system according to claim 1, wherein: The measuring light is a pattern light in which point lights are arranged in a grid shape.

5. The endoscope system according to any one of claims 1 to 4, wherein: The region is at least any one of a one-dimensional region, namely, a length, a two-dimensional region, namely, a surface area, and a three-dimensional region, namely, a volume.

6. The endoscope system according to claim 1, wherein: The endoscope performs the following processing: applying a light amount threshold value which is a preset threshold value of the light amount in the emission of the measurement light and the illumination light; and When the measuring light is irradiated and the illumination light is irradiated with a light amount suppressed relative to the measuring light, the measuring light is irradiated with a light amount equal to or greater than the light amount threshold and the illumination light is irradiated with a light amount less than the light amount threshold.

7. The endoscope system according to claim 6, wherein: The endoscope performs the following processing: The subject is continuously photographed by switching between the measurement irradiation and the observation irradiation in which the illumination light is irradiated with a light amount equal to or greater than the light amount threshold, The processor performs the following processing: An observation endoscopic image generated by imaging the object by the observation irradiation is displayed on a screen.

8. The endoscope system according to claim 6, wherein: The endoscope performs the following processing: The subject is continuously photographed by switching between the measurement irradiation and the measurement site confirmation irradiation in which the illumination light and the measurement light are irradiated with a light amount equal to or greater than the light amount threshold, The processor performs the following processing: Two types of optical endoscopic images generated by imaging the subject by the measurement site confirmation irradiation are displayed on a screen.

9. The endoscope system according to claim 7 or 8, wherein: The processor performs the following processing: A measurement light image generated by imaging the object through the measurement irradiation is displayed on a screen.

10. The endoscope system according to claim 9, wherein: The processor performs the following processing: Different screen displays are performed for each type of generated image.

11. The endoscope system according to claim 6, wherein: The endoscope performs the following processing: The subject is continuously photographed by switching between the measurement irradiation, the observation irradiation of irradiating the illumination light with a light amount equal to or greater than the light amount threshold, and the measurement site confirmation irradiation of irradiating the illumination light and the measurement light with a light amount equal to or greater than the light amount threshold, The processor performs the following processing: An observation endoscopic image generated by imaging the object by the observation irradiation and two optical endoscopic images generated by imaging the object by the measurement site confirmation irradiation are displayed on different screens.

12. An endoscope system comprising: Endoscope, to photograph the subject; an air supply device connected to the endoscope and configured to supply air from a front end portion of the endoscope at a plurality of stages of air supply volumes; and processor, The processor performs the following processing: controlling the emission of illumination light for illuminating a subject and measurement light for measuring a distance between the subject and the endoscope; irradiating the measuring light while the air supply device is supplying air at a first air supply volume, irradiating or extinguishing the illumination light at a light volume suppressed relative to the measuring light, and acquiring a first imaging signal from the endoscope that captures the subject; irradiating the measuring light, irradiating or extinguishing the illumination light with a light amount suppressed relative to the measuring light, and acquiring a second imaging signal from the endoscope that images the subject, while the air supply device is supplying air at a second air supply amount that is different from the first air supply amount; and An index value representing the amount of extension of the object is calculated and outputted by using the difference between the first distance information obtained by measuring the distances between multiple parts of the object and the endoscope based on the first camera signal and the second distance information obtained by measuring the distances between multiple parts of the object and the endoscope based on the second camera signal.

13. The endoscope system according to claim 12, wherein: The processor performs the following processing: The volume of the object is calculated according to the index value.

14. A method for operating an endoscope system, comprising the following steps: The air supply device supplies air at multiple stages of air supply amounts via the front end portion of the endoscope that images the object; controlling the emission of illumination light for illuminating a subject and measurement light for measuring distances between a plurality of parts of the subject and the endoscope; When the air supply amount is a first air supply amount, irradiating the measurement light, irradiating or extinguishing the illumination light with a light amount suppressed relative to the measurement light, and acquiring a first imaging signal from the endoscope that images the subject; When the air supply amount is a second air supply amount at a stage different from the first air supply amount, irradiating the measuring light, irradiating or extinguishing the illumination light at a light amount suppressed relative to the measuring light, and acquiring a second imaging signal from the endoscope that images the subject; calculating the area of ​​the object from first distance information obtained by measuring distances between a plurality of parts of the object and the endoscope based on the first imaging signal; and The region of the object is calculated from second distance information obtained by measuring distances between a plurality of sites of the object and the endoscope based on the second imaging signal.

Images