Endoscopic device, operating method thereof, and computer readable medium

Abstract

The present invention provides an endoscope device (10) that displays a more accurate scale for an observed object, an operating method thereof, and a program for the endoscope device. The endoscope device (10) includes a processor that, in a camera image obtained by photographing a subject having a specific area formed by measuring auxiliary light, determines the position of the specific area, sets a measurement mark that represents the actual size of the subject and has a scale with an end as a base point based on the position of the specific area, and creates a specific image in which the measurement mark is superimposed on the camera image in such a way that the position of the specific area overlaps with the base point of the scale of the measurement mark.

Description

Technical Field

[0001] The present invention relates to an endoscope device for measuring the size of an object, an operating method thereof, and a computer-readable medium. Background Art

[0002] In an endoscope device, the distance to a subject is measured or the length or size of the subject is calculated. For example, in Patent Document 1, a measurement auxiliary light is irradiated on the subject, thereby forming a light spot on the subject. The position of the light spot is determined from a camera image obtained by photographing the subject. Then, an identification graphic representing the actual size of the observation object contained in the subject is set according to the position of the light spot, and a measurement mark composed of the set identification graphic is displayed on the camera image. The measurement mark has, for example, a scale extending upward, downward, leftward, and rightward, so that the size of the observation object can be measured by aligning the displayed measurement mark with the observation object. In this way, by using the measurement mark displayed on the camera image, the size of the observation object can be measured.

[0003] Previous technical literature

[0004] Patent Literature

[0005] Patent Document 1: International Publication No. 2018 / 051680 Summary of the Invention

[0006] Technical issues to be solved by the invention

[0007] The surface of an object photographed by an endoscopic device sometimes has a three-dimensional shape such as a concave-convex shape. When a light spot generated by auxiliary measurement light is formed on the three-dimensional shape, an error may sometimes occur when a measurement mark is displayed that is different in size from the actual size of the observed object. This is because there is a difference in the depth direction distance of the focusing axis between the position on the three-dimensional shape where the light spot is formed and the position of the light spot when the three-dimensional shape portion does not have the concave-convex shape, that is, the position of the light spot at the root of the three-dimensional shape. In particular, in order to observe or diagnose the observed object in detail, a light spot is usually formed on the three-dimensional shape when the observed object is close to the observed object and is located at the center of the camera image. Therefore, especially when observing the observed object in detail, an error may sometimes occur in the scale displayed according to the position of the light spot.

[0008] In contrast, a method can be considered in which the three-dimensional shape of the subject or observation object is defined in advance and the scale is displayed offset by the predicted error. However, actual concave and convex shapes vary greatly, and the definition of the offset may become complicated.

[0009] In view of the above-mentioned actual situation, an object of the present invention is to provide an endoscope device and an operating method thereof, as well as a program for the endoscope device, which can display a more accurate scale for an observation object.

[0010] Means for solving technical problems

[0011] The present invention provides an endoscope device comprising: a measurement auxiliary light source unit for emitting measurement auxiliary light for measuring a subject; an imaging element for imaging the subject; and a processor. The processor determines the position of a specific area on the subject formed by the measurement auxiliary light, sets a measurement mark having a scale with an end as a base point, indicating the actual size of the subject, based on the position of the specific area, and creates a specific image with the measurement mark superimposed on a captured image of the subject captured by the imaging element, such that the position of the specific area overlaps with the base point of the scale of the measurement mark.

[0012] Preferably, the shape of the measurement mark is a straight line segment or a combination of straight line segments.

[0013] Preferably, the shape of the measurement mark is a circle or a combination of circles.

[0014] Preferably, the measurement mark has uneven graduations.

[0015] Preferably, the processor creates the specific image superimposed on the captured image such that the center of the measurement mark is located closer to the center than the position of the specific area.

[0016] Preferably, the measuring auxiliary light source unit emits the measuring auxiliary light so that a locus formed by the measuring auxiliary light on the subject differs from a locus formed by the optical axis of the imaging element.

[0017] Preferably, the processor receives a command to switch the measurement flag to be set, and switches and sets a plurality of different measurement flags in accordance with the command.

[0018] Preferably, the processor switches the measurement mark having scales with the end portion as a base point and sets the measurement mark having scales with the center portion as a base point.

[0019] Preferably, the endoscope device includes: an illumination light source unit that emits illumination light for illuminating the subject; and an illumination light switch that turns on or off the illumination light, wherein the measurement auxiliary light source unit does not emit the measurement auxiliary light when the illumination light is turned off by the illumination light switch.

[0020] Furthermore, the present invention is a method for operating an endoscope device, comprising the following steps: emitting measurement auxiliary light for measuring a subject; photographing the subject; determining the position of a specific area formed on the subject by the measurement auxiliary light; setting a measurement mark representing the actual size of the subject and having a scale with the end as a base point according to the position of the specific area; and producing a specific image in which the measurement mark is superimposed on a video image of the subject photographed by an imaging element in such a manner that the position of the specific area overlaps with the base point of the scale of the measurement mark.

[0021] Furthermore, the present invention is a program for an endoscopic device, which is a program for an endoscopic device comprising: a measurement auxiliary light source section that emits measurement auxiliary light for measuring a subject; and an imaging element that photographs the subject, the program for the endoscopic device causing a computer to execute the following functions: determining the position of a specific area formed on the subject by the measurement auxiliary light; setting a measurement mark representing the actual size of the subject and having a scale with the end as a base point according to the position of the specific area; and creating a specific image in which the measurement mark is superimposed on a video image of the subject photographed by the imaging element in such a manner that the position of the specific area overlaps with the base point of the scale of the measurement mark.

[0022] Effects of the Invention

[0023] According to the present invention, a more accurate scale can be displayed for an observation object. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is an external view of an endoscope device.

[0025] Figure 2 It is a plan view showing the distal end portion of the endoscope.

[0026] Figure 3 This is a block diagram showing the functions of an endoscope device.

[0027] Figure 4 This is a block diagram showing the functions of the measurement auxiliary light emitting unit.

[0028] Figure 5 This is an explanatory diagram of a spot SP formed on a subject by measuring auxiliary light.

[0029] Figure 6 It is an explanatory diagram showing the relationship between the distal end portion of the endoscope and the proximal end Px, the center vicinity Py, and the distal end Pz within the observation distance range Rx, and the relationship between the optical axis and the measurement auxiliary light.

[0030] Figure 7 This is a block diagram showing the functions of the signal processing unit.

[0031] Figure 8This is an image diagram of a captured image in which a light spot SP is formed.

[0032] Figure 9 This is an image diagram showing an example of a specific image in which a measurement mark is superimposed on a captured image.

[0033] Figure 10 This is an image diagram showing an example of a specific image in which a measurement mark is superimposed on a captured image.

[0034] Figure 11 This is an image diagram showing an example of a specific image in which a measurement mark is superimposed on a captured image.

[0035] Figure 12 is an explanatory diagram showing the types of measurement marks. Figure 12 (A) is a measurement mark having a line segment and scale in the left direction of the light spot SP. Figure 12 (B) is a measurement mark with a line segment and scale marks below the spot SP. Figure 12 (C) is a measurement mark having a line segment and scale marks in the upper right direction of the light spot SP.

[0036] Figure 13 This diagram illustrates measurement marks such as a scaled cross, a distorted cross, a circle, a cross, and a measurement point group.

[0037] Figure 14 This is an explanatory diagram showing the relationship between the measurement auxiliary light and the observation distance for a subject having a three-dimensional shape.

[0038] Figure 15 This is an image diagram showing an example of a specific image in which a measurement mark is superimposed on a captured image.

[0039] Figure 16 It is an explanatory diagram showing the position of the measurement mark in the captured image.

[0040] Figure 17 These are explanatory diagrams for explaining respective trajectories formed on a subject by illumination light and measurement auxiliary light.

[0041] Figure 18 This is an explanatory diagram for explaining switching of measurement marks.

[0042] Figure 19 This is a flowchart illustrating the flow of specific image display by the endoscope apparatus. DETAILED DESCRIPTION

[0043] like Figure 1As shown, the endoscope device 10 includes an endoscope 12, a light source device 13, a processor device 14, a monitor 15, and a keyboard 16 and a foot switch 17 as user interfaces. The endoscope 12 is optically connected to the light source device 13 and electrically connected to the processor device 14. The processor device 14 is electrically connected to the monitor 15 (display unit) that displays images. The keyboard 16 and foot switch 17 as user interfaces are connected to the processor device 14 and are used for various settings and operations on the processor device 14. In addition to the illustrated keyboard 16 and foot switch 17, the user interface also includes a mouse and the like.

[0044] The processor device 14 has a processor button 14a for executing various preset commands. The processor button 14a may be provided as part of an operation panel such as a touch panel connected to the processor device 14. The light source device 13 also has a light source button 13a for executing various preset commands.

[0045] The endoscope 12 includes an insertion portion 21 for insertion into a subject, an operating portion 22 provided at the base end of the insertion portion 21, and a universal cable 23. The operating portion 22 includes a viewer button 12a for the user of the endoscope 12 to execute various pre-set commands during operation of the endoscope 12. The universal cable 23 is a cable that integrates a light guide (not shown) for guiding illumination light emitted by the light source device 13, a control line for transmitting control signals for controlling the endoscope 12, a signal line for transmitting image signals obtained by photographing the observed object, and a power line for supplying power to various components of the endoscope 12. A connector 25 for connection to the light source device 13 is provided at the distal end of the universal cable 23. Furthermore, the light guide of the endoscope 12 is a light guide comprising bundled optical fibers.

[0046] The endoscope 12 has a normal mode and a length measurement mode, and these two modes are switched according to a command. The command for switching the mode can be set to any one or more of the processor button 14a, the scope button 12a, or the foot switch 17. By setting, these buttons function as a mode switching switch.

[0047] Normal mode displays an image obtained by capturing an observation object illuminated by illumination light. Therefore, measurement marks are not displayed in normal mode. Length measurement mode illuminates the observation object using illumination light and auxiliary measurement light, and displays measurement marks for measuring the object's size, etc., on the captured image. The auxiliary measurement light is used to measure the observation object.

[0048] Furthermore, a function of a still image acquisition command switch (still image acquisition command unit) for instructing acquisition of a still image of a captured image can be set to one or more of the processor button 14a, the viewer button 12a, or the foot switch 17. When the user instructs acquisition of a still image via the still image acquisition command switch, the screen of the monitor 15 is frozen and a warning sound (e.g., "beep") is emitted to indicate that still image acquisition is in progress. Then, for example, the still image of the captured image obtained before and after the operation of the viewer button 12a is stored in the still image storage unit 55 ( Figure 3 ). Furthermore, when the length measurement mode is set, it is preferable to store measurement information (described later) along with the still image of the captured image. The still image storage unit 55 is a storage unit such as a hard disk or USB (Universal Serial Bus) memory. If the processor device 14 is network-connectable, a still image storage server (not shown) connected to the network may store the still image of the captured image in place of or in addition to the still image storage unit 55.

[0049] Furthermore, a gesture recognition unit (not shown) that recognizes user gestures may be connected to the processor device 14. When the gesture recognition unit recognizes a specific gesture performed by the user, a still image acquisition command is issued. Mode switching, etc., may also be performed using the gesture recognition unit.

[0050] Furthermore, a line of sight input unit (not shown) provided near the monitor 15 may be connected to the processor device 14, and a still image acquisition command may be issued when the line of sight input unit recognizes that the user's line of sight remains within a predetermined area on the monitor 15 for a predetermined period of time or longer. Furthermore, a voice recognition unit (not shown) may be connected to the processor device 14, and a still image acquisition command may be issued when the voice recognition unit recognizes a specific voice uttered by the user. Mode switching, etc., can be performed using the voice recognition unit.

[0051] like Figure 2 As shown, the front end portion 12d of the endoscope 12 is roughly circular and is provided with: an objective lens 31, which is located closest to the subject among the optical components constituting the imaging optical system of the endoscope 12; an illumination lens 32, which is used to irradiate the subject with illumination light; a measurement auxiliary lens 33, which is used to illuminate the subject using the measurement auxiliary light described later; an opening 34, which is used to protrude the treatment instrument toward the subject; and an air and water supply nozzle 35, which is used to supply air and water.

[0052] Imaging optical system 44b ( Figure 3) extends perpendicular to the paper. A first longitudinal direction D1 is perpendicular to the optical axis Ax, and a second transverse direction D2 is perpendicular to the optical axis Ax and the first direction D1. The objective lens 31 and the auxiliary measurement lens 33 are arranged along the first direction D1.

[0053] like Figure 3 As shown, the light source device 13 includes a light source unit 41 and a light source control unit 42. The light source unit 41 (illumination light source unit) generates illumination light for illuminating the subject. The illumination light emitted from the light source unit 41 enters the light guide 43 and is irradiated onto the subject through the illumination lens 32. As the light source of the illumination light, the light source unit 41 can use a white light source that emits white light, or a plurality of light sources including a white light source and light sources that emit light of another color (for example, a blue light source that emits blue light). In addition, in this embodiment, the light source button 13a is configured to function as an illumination light switch that turns the illumination light on or off.

[0054] Inside the endoscope's distal end portion 12d are an illumination optical system 44a, an imaging optical system 44b, and a measurement-assistant light emitting unit (measurement-assistant light source unit) 45. The illumination optical system 44a includes an illumination lens 32. Light from the light guide 32 is irradiated onto the observation object via the illumination lens 43. The imaging optical system 44b includes an objective lens 31 and an imaging element 46. Light reflected from the observation object is incident on the imaging element 46 via the objective lens 31. As a result, a reflected image of the observation object is formed on the imaging element 46. The measurement-assistant light emitting unit 45 emits measurement-assistant light for measuring the object.

[0055] The imaging element 46 is a color imaging sensor that captures a reflected image of the subject and outputs an image signal. Preferably, the imaging element 46 is a CCD (Charge Coupled Device) imaging sensor, a CMOS (Complementary Metal-Oxide Semiconductor) imaging sensor, or the like. The imaging element 46 used in the present invention is a color imaging sensor that generates RGB image signals for the three colors of R (red), G (green), and B (blue). The imaging element 46 is controlled by the imaging control unit 47.

[0056] The image signal output from the imaging element 46 is sent to a CDS / AGC circuit 48. The CDS / AGC circuit 48 performs correlated double sampling (CDS) and automatic gain control (AGC) on the analog image signal. The image signal passed through the CDS / AGC circuit 48 is converted into a digital image signal by an A / D converter (A / D (Analog / Digital) converter) 49. The A / D-converted digital image signal is input to the processor device 14 via a communication interface 50.

[0057] The processor device 14 includes a communication I / F 51 connected to the communication I / F 50 of the endoscope 12, a signal processing unit 52, a display control unit 53, a system control unit 54, a still image storage unit 55, and a still image storage control unit 56. In the processor device 14, programs related to the signal processing unit 52, the display control unit 53, the system control unit 54, the still image storage unit 55, and the still image storage control unit 56 are loaded into a memory (not shown). The system control unit 54, which is composed of a processor, executes these programs, thereby realizing the functions of the signal processing unit 52, the display control unit 53, the system control unit 54, the still image storage unit 55, and the still image storage control unit 56.

[0058] The communication I / F 51 receives image signals transmitted from the communication I / F 50 of the endoscope 12 and transmits them to the signal processing unit 52. The signal processing unit 52 includes a built-in memory for temporarily storing the image signals received from the communication I / F 51. The signal processing unit 52 processes the image signals stored in the memory, i.e., the image signal group, to produce a captured image. Furthermore, when the signal processing unit 52 is set to length measurement mode, it can apply structure enhancement processing to emphasize structures such as blood vessels, and color difference enhancement processing to enhance color differences between normal and lesion areas of the observation object.

[0059] The display control unit 53 displays the captured image or specific image generated by the signal processing unit 52 on the monitor 15. The system control unit 54 controls the imaging element 46 via the imaging control unit 47 provided in the endoscope 12. The imaging control unit 47 also controls the CDS / AGC circuit 48 and the A / D converter 49 based on the control of the imaging element 46. The still image storage control unit 56 controls the still images of the captured images stored in the still image storage unit 55.

[0060] like Figure 4As shown, the auxiliary measurement light emitting unit 45 includes a light source 45a, an auxiliary measurement light generating element 45b, a prism 45c, and the auxiliary measurement lens 33. The light source 45a emits auxiliary measurement light. The auxiliary measurement light used to measure the subject emits light (specifically, visible light) of a color detectable by the pixels of the imaging element 46. The light source 45a includes a light-emitting element such as a laser light source LD (Laser Diode) or an LED (Light Emitting Diode), and a focusing lens that focuses the light emitted from the light-emitting element.

[0061] The wavelength of light emitted by the light source 45a is preferably red light, for example, between 600 nm and 650 nm. Alternatively, green light between 495 nm and 570 nm may be used. The auxiliary measurement light generating element 45b converts the light emitted from the light source into auxiliary measurement light for obtaining measurement information. Specifically, the auxiliary measurement light generating element 45b uses a collimating lens or a diffractive optical element (DOE) or the like to convert the light into auxiliary measurement light.

[0062] The prism 45c is an optical component used to change the direction of the auxiliary measurement light generated by the auxiliary measurement light generating element 45b. The prism 45c changes the direction of the auxiliary measurement light so that it intersects the field of view of the imaging optical system, which includes the objective lens 31 and the lens group. Details of the direction of the auxiliary measurement light will be described later. The auxiliary measurement light Lm emitted from the prism 45c passes through the auxiliary measurement lens 33 and is then irradiated onto the subject.

[0063] like Figure 5 As shown, by irradiating the subject with auxiliary measurement light, a specific area is formed on the subject. In this embodiment, the specific area is a light spot SP, which is a circular area. The communication I / F 51 as an image acquisition unit acquires a captured image 57 obtained by capturing the subject illuminated by the illumination light and having the light spot SP generated by the auxiliary measurement light. The position of the light spot SP in the captured image acquired by the communication I / F 51 is determined by the position determination unit 61 ( Figure 7 ) is determined. The observation distance, which is the distance between the endoscope distal end portion 12d and the subject, is calculated based on the determined position of the light spot SP. A measurement mark representing the actual size is set based on the observation distance. The set measurement mark is displayed on the captured image.

[0064] Alternatively, the auxiliary measurement lens 33 may be replaced with a slit for auxiliary measurement formed in the distal end portion 12d of the endoscope. Furthermore, it is preferable to apply an anti-reflection coating (AR (Anti-Reflection) coating) (anti-reflection portion) to the auxiliary measurement lens 33. The anti-reflection coating is provided because if the auxiliary measurement light is not transmitted through the auxiliary measurement lens 33 but is reflected, the proportion of the auxiliary measurement light irradiated on the subject is reduced, and the position determination unit 61 ( Figure 7 ) It is difficult to recognize the position of the spot SP formed on the subject by measuring the auxiliary light.

[0065] The auxiliary measurement light emitting unit 45 only needs to be capable of emitting auxiliary measurement light toward the field of view of the imaging optical system. For example, the light source 45a can be provided in a light source device, and the light emitted from the light source 45a can be guided to the auxiliary measurement light generating element 45b via an optical fiber. Furthermore, a configuration can be adopted in which, without using the prism 45c, the light source 45a and the auxiliary measurement light generating element 45b are tilted relative to the optical axis Ax of the imaging optical system 44b, thereby emitting auxiliary measurement light in a direction that spans the field of view of the imaging optical system.

[0066] Regarding measuring the direction of travel of the auxiliary light, such as Figure 6 As shown, auxiliary measurement light Lm is emitted when its optical axis enters the imaging angle of view of the imaging optical system (the region between the two solid lines L1). It can be seen that if observation is possible within the observation distance range Rx, the position of the light spot SP formed on the subject by the auxiliary measurement light within the imaging range (indicated by arrows Qx, Qy, and Qz) will differ at each point in the imaging range (indicated by arrows Qx, Qy, and Qz) at the near end Px, near the center Py, and far end Pz of range Rx (the point where each arrow Qx, Qy, and Qz intersects with the optical axis of the auxiliary measurement light Lm). The position of the endoscope distal end 12d is referred to as position P1. The observation distance is the distance between the endoscope distal end 12d and the subject. Therefore, the observation distance is the distance between position P1 and the near end Px, near the center Py, and far end Pz, respectively. Specifically, the observation distance is the distance from the origin of the optical axis Ax of the imaging optical system 44b of the endoscope distal end 12d to the subject. Axis Dv represents the observation distance. The imaging optical system's angle of view is shown within a region sandwiched between two solid lines L1 , and measurement is performed in a central region (a region sandwiched between two dotted lines L2 ) with little aberration within the imaging optical system's angle of view.

[0067] As described above, emitting auxiliary measurement light within the imaging optical system's field of view provides high sensitivity to the movement of the light spot position relative to changes in observation distance, enabling highly accurate measurement of the subject's size. The imaging element 46 captures the subject illuminated by the auxiliary measurement light, producing a captured image including the light spot SP. The position of the light spot SP in the captured image varies depending on the relationship between the optical axis Ax of the imaging optical system 44b and the optical axis of the auxiliary measurement light Lm, as well as the observation distance. However, closer observation distances increase the number of pixels required to display the same actual size (e.g., 5 mm), while longer observation distances result in fewer pixels.

[0068] Therefore, by storing in advance information indicating the relationship between the position of the light spot SP and the measurement information (number of pixels) corresponding to the actual size of the object, it is possible to calculate the measurement information from the position of the light spot SP.

[0069] like Figure 7 As shown, to identify the position of the light spot SP, calculate the observation distance to the subject, and set various measurement markers, the signal processing unit 52 of the processor device 14 includes: a position determination unit 61 that determines the position of the light spot SP in the captured image and calculates the observation distance; and an image processing unit 62 that sets various measurement markers based on the observation distance and creates a specific image that processes the captured image using the various measurement markers. The specific image is displayed on the monitor 15 via the display control unit 53.

[0070] When set to length measurement mode, the light source unit 41 and the auxiliary measurement light emitting unit 45 continuously emit illumination light and auxiliary measurement light. Depending on the situation, the auxiliary measurement light can be illuminated or dimmed. Furthermore, the captured image is set to a three-color RGB image, but other color images (luminance signal Y, color difference signals Cr and Cb) are also possible. Therefore, when set to length measurement mode, the signal processing unit 52 inputs a captured image of the subject illuminated by the illumination light and auxiliary measurement light. The captured image is acquired by the communication I / F 51 (image acquisition unit).

[0071] When set to normal mode, the light source unit 41 continuously emits illumination light. The illumination light is irradiated onto the subject via the light guide 43. In normal mode, the light source 45a of the auxiliary measurement light emitting unit 45 is stopped, and the auxiliary measurement light is extinguished. Therefore, when set to normal mode, the signal processing unit 52 receives a captured image of the subject illuminated by the illumination light. This captured image is acquired by the communication I / F 51 (image acquisition unit).

[0072] The position determination unit 61 determines the position of the light spot SP formed on the subject by the auxiliary measurement light. The position of the light spot SP is determined based on a captured image obtained by illuminating the subject with the illumination light and auxiliary measurement light in length measurement mode. The captured image captures an image of the subject, with the light spot SP formed by the auxiliary measurement light, via the imaging optical system and the imaging element. Therefore, the position determination unit 61 determines the position of the light spot SP on the imaging element based on the subject image. Furthermore, the position determination unit 61 includes a distance calculation unit 63. The distance calculation unit 63 can calculate the observation distance based on the position of the light spot SP.

[0073] The image processing unit 62 includes an image selection unit 64, a marker table 65, a measurement marker setting unit 66, a measurement marker switching receiving unit 67, and a specific image creating unit 68. The image selection unit 64 selects the image captured in the length measurement mode, from the captured image captured in the normal mode, as the target image for processing based on the position of the light spot SP. The marker table 65 pre-stores information indicating the relationship between the position of the light spot SP corresponding to the observation distance and measurement information (number of pixels) corresponding to the actual size of the object. The measurement marker setting unit 66 sets a measurement marker having a scale with the end as the base point, indicating the actual size of the object being observed on the object, based on the position of the light spot SP. The measurement marker switching receiving unit 67 receives a command to switch and set multiple measurement markers. The specific image creating unit 68 creates a specific image in which the measurement marker set by the measurement marker setting unit 66 is superimposed on the captured image so that the position of the light spot SP overlaps with the base point of the scale of the measurement marker.

[0074] The functions of the measurement mark setting unit 66 and the specific image generating unit 68 are described in detail below. Figure 8 As shown, in the length measurement mode, a captured image 71 obtained by illuminating a subject including a polyp 72 to be observed using illumination light and auxiliary measurement light is input to the signal processing unit 52. For example, since the polyp 72 has a spherical three-dimensional shape, the captured image 71 includes the polyp 72, the light spot SP, and a shadow 73 as appropriate.

[0075] The position determination unit 61 determines the position of the light spot SP based on the captured image 71 input to the signal processing unit 52. The measurement mark setting unit 66 refers to the mark table 65 and sets a measurement mark corresponding to the position of the light spot SP. The measurement mark has scales centered on the end portions and represents the actual size of the object being observed. The end portions refer to the portion of the measurement mark that is located further outward than the center, or to the start or end points.

[0076] like Figure 9As shown, the specific image creating unit 68 creates a specific image 74 in which the measurement mark 75 set by the measurement mark setting unit 66 is superimposed on the captured image 71, so that the position of the light spot SP overlaps the base point of the scale of the measurement mark 75. For more accurate measurement, the measurement mark 75 is preferably displayed so that it overlaps the position of the light spot SP. Therefore, even when displayed at a position separate from the light spot SP, it is preferably displayed as close to the light spot SP as possible. The measurement mark 75 is a straight line segment and has scale marks at the start and end points of the line segment, which are perpendicular to the straight line segment. If the measurement mark 75 is a line segment or other device with a start and end point, the start and / or end points themselves may serve as scale marks. In this case, for example, there may not be scale marks in the shape of a line segment perpendicular to the straight line segment. Furthermore, the measurement mark 75 may have the number "10" near the base point of the scale mark. This is the scale mark label 75a of the measurement mark 75, which is provided to easily identify the actual size of the line segment of the measurement mark 75 as 10 mm. Hereinafter, the numbers included in the measurement marks have the same meaning. The numerical values of the scale labels 75a can be changed according to the settings, and the measurement marks 75 may not display the scale labels 75a themselves.

[0077] Various types of measurement markers are used depending on the settings, for example, a straight line segment or a combination of straight line segments, a circle or a combination of circles, or a combination of a straight line segment and a circle.

[0078] like Figure 10 As shown, for example, specific image 76 includes a measurement mark 77 formed from a combination of straight line segments. Measurement mark 77 is formed by combining straight line segments into an L-shape. The segments extend upward and rightward on the page, with the corners of the L as base points. Scale marks are located at the base points and at the end points. Similar to measurement mark 75, measurement mark 77 includes the number "10" as a scale label 77a near the base points of the scale marks.

[0079] like Figure 11 As shown, for example, specific image 78 includes a measurement mark 79 shaped like a combination of a straight line segment and a circle. Measurement mark 79 is a combination of a circle and a line segment serving as the diameter of the circle. The line segment extends rightward on the page, with one of the intersections of the line segment and the circle serving as a base point. The intersection of the line segment and the circle serves as a scale mark for each line segment or circle. A scale mark 80 may be provided at the point where the line segment is halved or at the center of the circle. Similarly to measurement mark 75 or measurement mark 77, measurement mark 79 includes a scale mark label 79a with the number "10" near the base point of the scale mark.

[0080] like Figure 12As shown, in addition to these, the measurement mark can also be a measurement mark 81 ( Figure 12 (A)) A line segment extending from the base point in the downward direction of the paper including a measurement mark 82a ( Figure 12 (B)), or a line segment extending from the base point in the upper right direction of the paper including a scale label 83a for measurement ( Figure 12 (C)) and other shapes.

[0081] In addition, if Figure 13 As shown, a scaled cross with scale marks Mx added to at least one of the vertical or horizontal lines can also be used. Furthermore, a distorted cross with at least one of the vertical or horizontal lines tilted can be used. Furthermore, a cross can be formed by combining a circle and a cross. In these cases, the scale marks can be set from each end of the cross to the intersection of the cross. Alternatively, a measurement point group can be formed by combining a plurality of measurement points EP corresponding to the actual size of the light spot SP. In this case, the scale marks can be set as the distance from the light spot SP to the measurement point EP.

[0082] Furthermore, the number of measurement marks can be one or more, and the color of the measurement marks can be changed according to the actual size. Furthermore, the size of the measurement marks can be set to a size corresponding to the observed object, or smaller or larger than the observed object. The actual size of the measurement marks can be set to any value (e.g., 2mm, 3mm, 10mm, etc.) depending on the observed object and the purpose of the observation.

[0083] Furthermore, the scale of the measurement mark may be uneven. For example, when measuring a three-dimensional object, the measurement mark setting unit 66 sets the measurement mark with a strain that takes into account the three-dimensional shape of the object. This three-dimensional shape is taken into account by estimating the height of the three-dimensional shape based on the distance to the object calculated by the distance calculation unit 63, or by estimating the size or shape of the three-dimensional shape through image analysis of the captured image. Machine learning techniques using a learned model of the captured image can be used for image analysis.

[0084] For example, Figure 14As shown, by measuring the auxiliary light Lm, a spot of light SP2 is formed at the apex 72a of the polyp 72. The distance to the observation object calculated from the spot of light SP2 is the distance D5 between the position P1 of the endoscope distal end portion 12d and the position P2 of the spot of light SP2. Furthermore, by measuring the auxiliary light Lm, a spot of light SP1 is formed at the end 72b of the polyp 72. The distance to the observation object calculated from the spot of light SP1 is the distance D6 between the position P1 of the endoscope distal end portion 12d and the position P3 of the spot of light SP1. Therefore, the height of the polyp 72 is the distance D3, which is the difference between the distance D6 and the distance D5.

[0085] The measurement mark setting unit 66 calculates distance D3 as the height of the observation object by, for example, storing distances D6 and D5. Furthermore, the three-dimensional shape of the observation object is ascertained using information on its size and / or shape, inferred through image analysis of the observed image. The measurement mark setting unit 66 sets measurement marks with strain that takes into account the thus-ascertained three-dimensional shape of the observation object.

[0086] For example, Figure 15 As shown, the measurement mark setting unit 66 sets a measurement mark 85 having a strain that takes into account the three-dimensional shape of the polyp 72 based on information such as the height, size, and shape of the polyp 72. The measurement mark 85 includes scale marks 85a, 85b, and 85c. Scale mark 85a is located at the starting point of the measurement mark 85, and scale mark 85c is located at the end point of the measurement mark 85. Scale mark 85b is located closer to the end point than the center of the measurement mark 85. Furthermore, the number "10" on scale mark label 85d and scale label 85e indicates that the actual measured dimension from scale mark 85a to scale mark 85b is 10 mm, and the actual measured dimension from scale mark 85b to scale mark 85c is 10 mm, respectively. In the measurement mark 85, the distance from scale mark 85a to scale mark 85b and the distance from scale mark 85b to scale mark 85c are not the same length on the observed image. However, since the polyp 72 is actually spherical, the scale marks of the measurement mark 85 represent the actual size. The measurement mark setting unit 66 sets the measurement mark 85, and the specific image creating unit 68 creates the specific image 84 by superimposing the measurement mark 85 on the captured image.

[0087] As described above, the measurement mark setting unit 66 sets a measurement mark representing the actual size and having a scale with the end as the base point based on the position of the light spot SP. The specific image creating unit 68 creates a specific image in which the measurement mark set by the measurement mark setting unit 66 is superimposed on the camera image, such that the position of the light spot SP overlaps with the base point of the scale of the measurement mark. To obtain a more detailed view of the object being measured, it is natural to position it in the center of the endoscope-based camera image. Therefore, by creating a specific image with the measurement mark superimposed, the measurement mark can be more appropriately positioned. This allows, for example, a more accurate scale display of the object being observed can be achieved compared to placing the measurement mark at the periphery of the camera image.

[0088] Furthermore, the object being measured may have a three-dimensional shape. Therefore, by creating a specific image with measurement marks superimposed on it, as described above, when the light spot SP is formed at the vertex of the three-dimensional shape, it is possible to reduce errors that can result in a measurement value based on the measurement marks being shorter than the actual distance to the object being measured or smaller than the actual size of the object being measured. This allows for a display of measurement marks that is closer to the actual distance. This allows for a more accurate scale to be displayed for the object being observed. This prevents underestimation of the size of the object being observed, such as a polyp, and enables more appropriate diagnosis.

[0089] Furthermore, the specific image generator 68 preferably generates a specific image in which the measurement marker is superimposed on the captured image so that its center is positioned more centrally than the position of the light spot SP. To obtain a more detailed view of the object being measured, it is generally natural to position it in the center of the endoscope-based captured image. Therefore, by generating a specific image in which the measurement marker is positioned more centrally than the light spot SP, a more appropriate placement of the measurement marker is possible.

[0090] For example, Figure 16 As shown in FIG. 8 , in the specific image 86 , the center of the measurement mark is located in the region 87 which is a region closer to the center of the specific image 86 than the position of the spot SP, thereby enabling the position of the measurement mark to be arranged more appropriately. Figure 16 In the example, region 87 is the area indicated by diagonal lines. Therefore, for example, compared to placing measurement markers on the periphery of the captured image, a more accurate scale can be displayed for the observed object. Furthermore, the periphery of the captured image can be defined as an area other than region 87 within specific image 86.

[0091] Furthermore, the measurement-assist light emitting unit 45 preferably emits the measurement-assist light so that the trajectory formed by the measurement-assist light on the subject differs from the trajectory formed by the optical axis of the imaging element (the optical axis of the imaging optical system). Furthermore, the "different trajectories" refer to trajectories that are inconsistent. This allows the observation object to be positioned closer to the center of the captured image, and the light spot SP to be formed further outward than near the optical axis of the imaging optical system. This allows the observation object to be positioned in the center, making it easier to observe.

[0092] For example, Figure 17 As shown, the auxiliary measurement light is adjusted so that, in a captured image 91 recording a track 93 formed by the auxiliary measurement light on the subject and a track 92 formed by the optical axis of the imaging optical system, when the optical axis of the imaging optical system is at observation point 94, the spot SP1 generated by the auxiliary measurement light is located to the left of observation point 94 in the captured image 91. Furthermore, when the observation location is subsequently shifted and the optical axis of the imaging optical system is at observation point 95, the spot SP2 generated by the auxiliary measurement light is located to the left of observation point 95 in the captured image 91. Furthermore, the track 93 formed by the auxiliary measurement light is preferably located outside the track formed by the optical axis of the imaging optical system on the subject, but may also be located to the left, right, top, or bottom. Therefore, the measurement mark is positioned closer to the center of the captured image than the spot SP, enabling a more accurate scale display of the observed object.

[0093] Furthermore, the display of measurement marks is switched as needed. The measurement mark switching receiving unit 67 receives a command to switch the measurement mark to be set. The measurement mark setting unit 66 switches and sets a plurality of different measurement marks in response to the command from the measurement mark switching receiving unit 67. As described above, various shapes can be set for measurement marks that represent actual dimensions and have scales based on the end points. Therefore, for example, by pre-assigning a command to switch the setting of measurement marks to one or more of the processor button 14a, the viewer button 12a, or the foot switch 17, the user can switch to the most appropriate measurement mark during observation to create a specific image.

[0094] Furthermore, the measurement mark setting unit can switch from a measurement mark having scales based on the end portions to a measurement mark having scales based on the center portion. Even when setting a measurement mark having scales based on the center portion, it is preferable to create a specific image in which the measurement mark is superimposed on the captured image so that the light spot SP overlaps with the base point of the scale of the measurement mark.

[0095] like Figure 18As shown, in a specific image 101, when a polyp 102 that resembles two connected balls is observed, a measuring mark 103 is superimposed on the captured image so that the light spot SP overlaps the end of the measuring mark 103. The scale label 103a of the measuring mark 103 is displayed as "10", so the length from the start point to the end point is 10 mm in actual measurement. Here, in order to measure the total length of the polyp 102, the foot switch 17, for example, which serves as the measuring mark switching receiving unit 67, is operated. The foot switch 17 includes a left switch 17a and a right switch 17b ( Figure 1 Left switch 17a is a toggle switch that cyclically switches between and displays multiple different measurement marks. These multiple measurement marks include not only those with scales based on the ends but also those with scales based on the center. Right switch 17b is a confirmation switch. Once the desired measurement mark is displayed, the user presses right switch 17b to activate the confirmation switch.

[0096] For example, switching from specific image 101 to specific image 104 is like switching from measurement marker 103 to measurement marker 105. In this case, the position of the light spot SP remains unchanged, and the measurement marker is switched from measurement marker 103 to measurement marker 105. Since the position of the light spot SP remains unchanged, the user moves the imaging optical system to the right to measure the polyp 102. The measurement marker is a cross-shaped marker with line segments extending upward, downward, and leftward from the center. The scale label 105a displays "5," so each line segment represents a measured dimension of 5 mm. This allows the size or length of the polyp 102 to be measured and understood.

[0097] Furthermore, switching from specific image 101 to specific image 106 occurs when measuring marker 103 is switched to measuring marker 107. In this case, the position of the light spot SP is changed to the center of the captured image. This allows the object to be observed, photographed, or measured in the center of the captured image. Based on specific image 106, scale label 107a displays "5," indicating that the shorter length of the three-dimensional shape of polyp 102, which resembles two connected spheres, is approximately 10 mm.

[0098] Furthermore, the measurement mark switching receiving unit 67 can switch from specific image 101 to specific image 104, and vice versa. Similarly, it can switch from specific image 101 to specific image 106, and vice versa. Furthermore, it can switch from specific image 104 to specific image 106, and vice versa. Furthermore, it can switch from specific image 104 to specific image 106, and vice versa. Furthermore, in addition to switching between measurement marks of different shapes, it is also possible to switch between measurement marks of the same shape but with different scales. This allows the user to easily set the measurement mark they deem more appropriate, as needed.

[0099] In addition, when the illumination light is turned off by turning on or off the illumination light switch for illuminating the subject, it is preferable that the measurement auxiliary light emitting unit 45 does not emit the measurement auxiliary light. As described above, the light source button 13a ( Figure 1 ) has the function of an illumination light switch. When the illumination light is turned off by the light source button 13a, for example, when the endoscope is not inside the body, the measurement auxiliary light emitting unit 45 does not emit the measurement auxiliary light. In this embodiment, the measurement auxiliary light is laser light, and therefore, from a safety perspective, it is preferably not illuminated when the endoscope is outside the body. However, by providing the illumination light switch with an interlock function for the measurement auxiliary light, even if a command to illuminate the measurement auxiliary light is issued, the inadvertent emission of the measurement auxiliary light can be prevented. Furthermore, since the illumination of the measurement auxiliary light is activated when switching to the length measurement mode, as described above, even if one or more of the processor button 14a, the scope button 12a, or the foot switch 17, for example, which are set with a mode switching command, is inadvertently operated, the emission of the measurement auxiliary light can be prevented when the illumination light is turned off by the illumination light switch, for example, when the endoscope is outside the body.

[0100] Next, regarding the effects of the above structure, refer to Figure 19 The flowchart of FIG. 1 is used to explain this. First, the subject is observed in normal mode (step ST110). For example, if an observation object that needs to be observed and measured is found in the subject, the mode is switched to length measurement mode (Yes in step ST120). If the mode is not switched to length measurement mode (No in step ST120), observation in normal mode is continued.

[0101] When the mode is switched to length measurement mode, observation is performed in length measurement mode (step ST130). The auxiliary measurement light emitting unit 45 emits auxiliary measurement light (step ST140), and the imaging element captures an image of the subject (step ST150). The position determination unit 61 determines the position of the light spot SP based on the captured image (step ST160). Depending on the situation, the distance calculation unit 63 calculates the distance between the endoscope distal end portion 12d and the subject (step ST170) and transmits this information to the measurement mark setting unit 66 and other units.

[0102] The measurement mark setting unit 66 uses the obtained information to set the measurement mark (step ST180). The measurement mark setting unit 66 sets the measurement mark that represents the actual size and has a scale with the end as the base point based on the position of the light spot SP determined by the position determination unit 61. In the case of switching the measurement mark (No in step ST190), the process returns to before setting the measurement mark. In the case of not switching the measurement mark (Yes in step ST190), the process proceeds to the creation of a specific image. Regarding the specific image, a specific image is created in which the measurement mark is superimposed on the camera image in such a way that the position of the light spot SP overlaps with the base point of the scale of the measurement mark (step ST200). After the specific image is created, the specific image is displayed on the monitor 15 ( Figure 1 ) etc. (step ST210).

[0103] In the above-described embodiment, the hardware configuration of the processing units that perform various processes, such as the signal processing unit 52, the display control unit 53, or the system control unit 54, is composed of various processors as described below. These processors include general-purpose processors such as CPUs (Central Processing Units) that execute software (programs) and function as various processing units; processors such as FPGAs (Field Programmable Gate Arrays) whose circuit configuration can be modified after manufacture, such as programmable logic devices (PLDs); and processors with circuit configurations specifically designed to perform various processes, such as dedicated circuits.

[0104] One processing unit may be composed of one of these various processors, or may be composed of a combination of two or more processors of the same or different types (for example, a combination of multiple FPGAs, CPUs and FPGAs). In addition, multiple processing units may be composed of one processor. As an example of multiple processing units composed of one processor, first, there is a method in which a processor is composed of a combination of one or more CPUs and software, as represented by computers such as clients and servers, and the processor functions as multiple processing units. Secondly, there is a method in which a processor is used that realizes the functions of the entire system including multiple processing units by one IC (Integrated Circuit) chip, as represented by a system on chip (SoC). In this way, as a hardware structure, various processing units are composed of one or more of the above-mentioned various processors.

[0105] More specifically, the hardware structure of these various processors is a circuit formed by combining circuit elements such as semiconductor devices. Another embodiment of the present invention is an endoscope device comprising: a measurement auxiliary light source unit that emits measurement auxiliary light for measuring a subject; and an imaging element that images the subject. In this endoscope device, the processor performs the following processing: determining the position of a specific area formed on the subject by the measurement auxiliary light, setting a measurement mark having a scale indicating the actual size and having an end as a base point based on the determined position of the specific area, and creating a specific image with the measurement mark superimposed on a camera image of the subject captured by the imaging element in such a manner that the position of the specific area overlaps the base point of the scale of the measurement mark.

[0106] The present invention is not limited to the above-described embodiment, and various configurations can be employed without departing from the spirit of the present invention. Furthermore, the present invention relates not only to a program but also to a storage medium storing the program.

[0107] Explanation of symbols

[0108] 10-Endoscope device, 12-Endoscope, 12a-Observer button, 12d-Front end, 13-Light source device, 13a-Light source button, 14-Processor device, 14a-Processor button, 15-Monitor, 16-Keyboard, 17-Foot switch, 17a-Left switch, 17b-Right switch, 21-Insertion portion, 22-Operation portion, 23-Universal cable, 25-Connector, 31-Objective lens, 32-Illumination lens, 33-Auxiliary measurement lens, 34-Opening, 35-Air and water supply nozzle, 41-Light source portion, 42-Light source control portion, 43-Light guide, 44a-Illumination light 44b-imaging optical system, 45-measurement auxiliary light emitting unit, 45a-light source, 45b-measurement auxiliary light generating element, 45c-prism, 46-imaging element, 47-imaging control unit, 48-CDS / AGC circuit, 49-A / D converter, 50, 51-communication I / F, 52-signal processing unit, 53-display control unit, 54-system control unit, 55-still image storage unit, 56-still image storage control unit, 57, 91-camera image, 61-position determination unit, 62-image processing unit, 63-distance calculation unit, 64-image selection unit, 65- Marking table, 66-measurement marking setting unit, 67-measurement marking switching receiving unit, 68-specific image creating unit, 71, 74, 76, 78, 84, 86, 101, 104, 106-specific image, 72, 102-polyp, 72a-apex, 72b-end, 73-shadow, 75, 77, 79, 81, 82, 83, 85, 103, 105, 107-measurement marking, 75a, 77a, 80a, 81a, 82a, 83a, 85d, 85e, 103a, 105a, 107a-scale label, 85a, 85b, 8 5c-scale, 87-area, 92, 93-track, 94, 95-observation point, L1-solid line, L2-dashed line, D1-first direction, D2-second direction, D3-height of light spot SP1, D5, D6-observation distance, Dv-observation distance, Lm-measurement auxiliary light, Ax-optical axis of the camera optical system, Px-near end, Py-near center, Pz-far end, P1~P3-position, Qx, Qy, Qz-photographic range, Rx-range of observation distance, SP, SP1, SP2-light spot, EP-measuring point, Mx-scale, ST110~ST210-steps.

Claims

1. An endoscope device comprising: A measurement auxiliary light source unit emits measurement auxiliary light for measuring the subject; An imaging element for photographing the subject; and processor, The processor performs the following processing: determining a position of a specific area formed by the measuring auxiliary light on the subject, A measuring mark indicating the actual size of the subject and having a scale with an end portion as a base point is set according to the position of the specific area; A specific image is created in which the measurement mark is superimposed on the captured image of the subject captured by the imaging element so that the position of the specific area overlaps with the base point of the scale of the measurement mark.

2. The endoscope device according to claim 1, wherein The shape of the measurement mark is a straight line segment or a combination of straight line segments.

3. The endoscope device according to claim 1, wherein The shape of the measurement mark is a circle or a combination of circles.

4. The endoscope device according to claim 1, wherein The scale of the measuring mark is uneven.

5. The endoscope device according to claim 2, wherein The scale of the measuring mark is uneven.

6. The endoscope device according to claim 3, wherein: The scale of the measuring mark is uneven.

7. The endoscopic device according to any one of claims 1 to 6, wherein: The processor creates the specific image superimposed on the captured image such that the center of the measurement mark is located closer to the center than the position of the specific area.

8. The endoscopic device according to any one of claims 1 to 6, wherein: The measurement auxiliary light source section emits the measurement auxiliary light so that a locus formed by the measurement auxiliary light on the object is different from a locus formed by the optical axis of the imaging element.

9. The endoscopic device according to claim 7, wherein: The measurement auxiliary light source section emits the measurement auxiliary light so that a locus formed by the measurement auxiliary light on the object is different from a locus formed by the optical axis of the imaging element.

10. The endoscopic device according to any one of claims 1 to 6, wherein: The processor receives a command to switch a measurement marker to be set, The plurality of measurement markers that are different from each other are switched and set according to the command.

11. The endoscopic device according to claim 7, wherein: The processor receives a command to switch a measurement marker to be set, The plurality of measurement markers that are different from each other are switched and set according to the command.

12. The endoscopic device according to claim 8, wherein The processor receives a command to switch a measurement marker to be set, The plurality of measurement markers that are different from each other are switched and set according to the command.

13. The endoscopic device according to any one of claims 1 to 6, wherein: The processor switches the measurement mark having the scale with the end portion as a base point to set a measurement mark having the scale with the center portion as a base point.

14. The endoscopic device according to claim 7, wherein: The processor switches the measurement mark having the scale with the end portion as a base point to set a measurement mark having the scale with the center portion as a base point.

15. The endoscopic device according to claim 8, wherein The processor switches the measurement mark having the scale with the end portion as a base point to set a measurement mark having the scale with the center portion as a base point.

16. The endoscopic device according to claim 10, wherein The processor switches the measurement mark having the scale with the end portion as a base point to set a measurement mark having the scale with the center portion as a base point.

17. The endoscope device according to any one of claims 1 to 6, comprising: an illumination light source unit for emitting illumination light for illuminating a subject; and an illumination light switch, for lighting or extinguishing the illumination light, When the illumination light is turned off by the illumination light switch, the measurement auxiliary light source section does not emit the measurement auxiliary light.

18. The endoscope device according to claim 7, comprising: an illumination light source unit for emitting illumination light for illuminating a subject; and an illumination light switch, for lighting or extinguishing the illumination light, When the illumination light is turned off by the illumination light switch, the measurement auxiliary light source section does not emit the measurement auxiliary light.

19. The endoscope device according to claim 8, comprising: an illumination light source unit for emitting illumination light for illuminating a subject; and an illumination light switch, for lighting or extinguishing the illumination light, When the illumination light is turned off by the illumination light switch, the measurement auxiliary light source section does not emit the measurement auxiliary light.

20. The endoscope device according to claim 10, comprising: an illumination light source unit for emitting illumination light for illuminating a subject; and an illumination light switch, for lighting or extinguishing the illumination light, When the illumination light is turned off by the illumination light switch, the measurement auxiliary light source section does not emit the measurement auxiliary light.

21. The endoscope device according to claim 13, comprising: an illumination light source unit for emitting illumination light for illuminating a subject; and an illumination light switch, for lighting or extinguishing the illumination light, When the illumination light is turned off by the illumination light switch, the measurement auxiliary light source section does not emit the measurement auxiliary light.

22. A method for operating an endoscope device, comprising the following steps: Emitting metering auxiliary light for measuring the subject; photographing the subject; determining a position of a specific area formed by the measurement auxiliary light on the subject; setting a measuring mark indicating the actual size of the subject and having a scale with an end portion as a base point according to the position of the specific area; and A specific image is created in which the measurement mark is superimposed on the captured image of the subject so that the position of the specific area overlaps with the base point of the scale of the measurement mark.

23. A non-transitory computer-readable medium storing a computer-executable program for an endoscope apparatus, the endoscope apparatus comprising: a measurement auxiliary light source unit for emitting measurement auxiliary light for measuring a subject; and an imaging element for imaging the subject, the computer-executable program causing the computer to perform the following functions: determining a position of a specific area formed by the measurement auxiliary light on the subject; setting a measuring mark indicating the actual size of the subject and having a scale with an end portion as a base point according to the position of the specific area; and A specific image is created in which the measurement mark is superimposed on the captured image of the subject captured by the imaging element so that the position of the specific area overlaps with the base point of the scale of the measurement mark.

Images