Endoscope system and operating method thereof

Abstract

The present invention provides an endoscope system and an operating method thereof. The endoscope system, when switched from a multi-lighting mode in which a plurality of illumination lights are automatically switched to illuminate an observation object, to a single-lighting mode in which only a specific illumination light is emitted, can switch to the multi-lighting mode without placing a burden on an operator. When the multi-lighting mode is automatically switched to the single-lighting mode by satisfying a pre-set single-lighting switching condition, the system automatically switches from the single-lighting mode to the multi-lighting mode when a pre-set multi-lighting restart condition is satisfied.

Description

Technical Field

[0001] The present invention relates to an endoscope system and an operating method thereof for switching a plurality of illumination lights illuminating different wavelength bands and switching and displaying observation images corresponding to each illumination light. Background Art

[0002] In recent years, endoscope systems, which include a light source device, an endoscope, and a processor device, have become widely used in the medical field. In an endoscope system, illumination light is irradiated from the endoscope onto an observation object, and the endoscope's imaging element captures the object illuminated by the illumination light, generating RGB image signals. The image of the observation object is then displayed on a monitor.

[0003] Furthermore, in recent years, multiple illumination lights of different wavelengths have been used to illuminate an observation object, thereby obtaining a large amount of diagnostic information from the observation object. For example, in Patent Document 1, a first illumination light and a second illumination light are switched according to a specific illumination pattern while emitting light, and a first observation image and a second observation image are switched according to a specific display pattern and displayed on a display.

[0004] Previous technical literature

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. 2019 / 093356 Summary of the Invention

[0007] Technical issues to be solved by the invention

[0008] In Patent Document 1, in cases where the front end of the endoscope is accidentally moved or the focus of the observation object is deviated, making it difficult for the illumination light to illuminate the observation object, the multi-light mode of switching multiple illumination lights for illumination is sometimes inappropriate. Therefore, when pre-set specified conditions are met, the multi-light mode is switched to a single-light mode that only emits specific illumination light.

[0009] However, even when switching to single-shot mode, if the change in imaging conditions related to the observed object is only temporary, and immediately returns to imaging conditions suitable for multi-shot mode, the operator often wishes to resume observation using multi-shot mode. In such cases, manually reselecting the multi-shot mode is very cumbersome and stressful for the operator.

[0010] The object of the present invention is to provide an endoscope system and its working method, wherein the endoscope system can switch to the multi-lighting mode without burdening the operator when it has switched from the multi-lighting mode that automatically switches multiple lighting lights to illuminate the observation object to the single-lighting mode that only emits specific lighting light.

[0011] Means for solving technical problems

[0012] The endoscope system of the present invention comprises: a plurality of semiconductor light sources that emit light of different wavelength bands; a light source processor that controls the plurality of semiconductor light sources and performs controls related to a single light-emitting mode and a multi-light-emitting mode, wherein in the single light-emitting mode, only a specific illumination light having a specific illumination ratio is emitted, and in the multi-light-emitting mode, according to a specific illumination pattern, a plurality of illumination lights including a first illumination light having a first illumination ratio and a second illumination light having a second illumination ratio different from the first illumination ratio are switched while emitting light; and an image control processor that performs the following processing: when the multi-light-emitting mode is automatically switched to the single light-emitting mode by satisfying a pre-set single light-emitting switching condition, the single light-emitting mode is automatically switched to the multi-light-emitting mode when a pre-set multi-light-emitting restart condition is satisfied.

[0013] The preferred image control processor performs the following processing: when the multi-lighting restart condition and the restart permission condition are met, it automatically switches from the single-lighting mode to the multi-lighting mode; when the multi-lighting restart condition is met and the restart permission condition is not met, it is prohibited to automatically switch to the multi-lighting mode.

[0014] The restart permission condition is preferably when the operator has not selected the single-light emission mode. The restart permission condition is preferably when the restart permission time has not elapsed after switching to the single-light emission mode. The restart permission condition is preferably when the multi-light emission mode can be implemented. Preferably, a magnification change unit for changing the magnification of the observation object is provided, and the restart permission condition is when the magnification change unit has not been switched between use and non-use. The restart permission condition is preferably settable by the operator.

[0015] The multi-lighting restart condition is preferably a condition where a change in imaging conditions related to the observation object is within an allowable range. The multi-lighting restart condition is preferably a condition obtained by combining at least one of the following conditions: the observation object changes from a first portion to a second portion and then returns to the first portion within a predetermined time, or changes from a second portion to the first portion and then returns to the second portion within a predetermined time; the brightness of the observation object becomes greater than a first brightness threshold or less than a second brightness threshold that is greater than the first brightness threshold; the amount of change in the magnification of the observation object becomes less than a magnification threshold when the magnification of the observation object is changed; the amount of change in the observation distance becomes less than a distance threshold; and the blur amount of the observation image obtained by imaging the observation object becomes less than a blur amount threshold.

[0016] The image control processor preferably performs the following processing: in the case of a single illumination mode, a control is performed to display a specific observation image obtained by photographing an observation object illuminated by a specific illumination light on a display; in the case of a multi-illumination mode, a control is performed to switch a plurality of observation images including a first observation image obtained by photographing an observation object illuminated by a first illumination light and a second observation image obtained by photographing an observation object illuminated by a second illumination light according to a specific display style and display them on the display.

[0017] The present invention is a working method of an endoscope system, wherein the endoscope system comprises: a plurality of semiconductor light sources that emit light of different wavelength bands; a light source processor that controls the plurality of semiconductor light sources and performs control related to a single light-emitting mode and a multi-light-emitting mode, wherein in the single light-emitting mode, only a specific illumination light with a specific illumination ratio is emitted, and in the multi-light-emitting mode, according to a specific illumination pattern, a plurality of illumination lights including a first illumination light with a first illumination ratio and a second illumination light with a second illumination ratio different from the first illumination ratio are switched while emitting light; and an image control processor, wherein in the working method of the endoscope system, the image control processor performs the following processing: when the multi-light-emitting mode is automatically switched to the single light-emitting mode by satisfying a pre-set single light-emitting switching condition, the multi-light-emitting mode is automatically switched to the multi-light-emitting mode when a pre-set multi-light-emitting restart condition is satisfied.

[0018] Effects of the Invention

[0019] According to the present invention, when switching from the multi-emission mode that automatically switches multiple illumination lights to illuminate the observation object to the single-emission mode that emits only specific illumination light, switching to the multi-emission mode can be performed without placing a burden on the operator. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is an external view of the endoscope system according to the first embodiment.

[0021] Figure 2 This is a block diagram showing the functions of the endoscope system according to the first embodiment.

[0022] Figure 3 It is a graph showing the emission spectra of purple light V, blue light B, green light G, and red light R.

[0023] Figure 4 It is an image diagram representing a normal image.

[0024] Figure 5 Graph showing the emission spectrum of the first illumination light including purple light V, blue light B, green light G, and red light R.

[0025] Figure 6 : is an image diagram showing the first observation image.

[0026] Figure 7 Graph showing the emission spectrum of the second illumination light including purple light V, blue light B, green light G, and red light R.

[0027] Figure 8 : is an image diagram showing the second observation image.

[0028] Figure 9 It is an explanatory diagram showing the emission of the first illumination light and the second illumination light and the display of the first observation image and the second observation image in the multi-emission mode.

[0029] Figure 10 This is an explanatory diagram showing a case where the multi-lighting mode is automatically switched to the single-lighting mode.

[0030] Figure 11 This is an explanatory diagram showing a case where the multi-lighting mode is automatically switched to the single-lighting mode when the usage time of the multi-lighting mode becomes equal to or longer than a time threshold.

[0031] Figure 12 This is an explanatory diagram showing a case where the multi-light emission mode is automatically switched to the single-light emission mode when the number of times a still image is saved exceeds a number threshold.

[0032] Figure 13 This is a block diagram showing the functions of the imaging condition acquisition unit.

[0033] Figure 14 This is an explanatory diagram showing a case where the multi-light emission mode is automatically switched to the single-light emission mode when the observation site changes from the first site to the second site or when the observation site changes from the second site to the first site.

[0034] Figure 15 This is an explanatory diagram for explaining a case where the multi-light emission mode is automatically switched to the single-light emission mode when the brightness becomes equal to or lower than the first brightness threshold or when the brightness becomes equal to or higher than the second brightness threshold.

[0035] Figure 16 This is an explanatory diagram showing a case where the multi-emission mode is automatically switched to the single-emission mode when the magnification change amount exceeds the magnification threshold value.

[0036] Figure 17 This is an explanatory diagram showing a case where the multi-emission mode is automatically switched to the single-emission mode when the amount of change in the observation distance exceeds a distance threshold.

[0037] Figure 18 This is an explanatory diagram showing a case where the multi-emission mode is automatically switched to the single-emission mode when the blur amount exceeds the blur amount threshold.

[0038] Figure 19 This is an image diagram showing a menu for setting the single light emission switching conditions.

[0039] Figure 20 This is an explanatory diagram showing a case where the single-lighting mode is automatically switched to the multi-lighting mode.

[0040] Figure 21 This is an explanatory diagram showing a situation where the single-light emission mode is automatically switched to the multi-light emission mode when returning to the original observation site for observation.

[0041] Figure 22 This is an explanatory diagram showing a case where the single-lighting mode is automatically switched to the multi-lighting mode when the brightness becomes equal to or higher than the first brightness threshold or becomes equal to or lower than the second brightness threshold.

[0042] Figure 23 This is an explanatory diagram showing a case where the single-emission mode is automatically switched to the multi-emission mode when the magnification change amount becomes smaller than the magnification threshold value.

[0043] Figure 24 This is an explanatory diagram showing a case where the single-emission mode is automatically switched to the multi-emission mode when the amount of change in the observation distance becomes equal to or smaller than a distance threshold.

[0044] Figure 25 This is an explanatory diagram showing a case where the single-emission mode is automatically switched to the multi-emission mode when the blur amount becomes equal to or smaller than a blur amount threshold.

[0045] Figure 26 It is a flowchart showing a series of processes including the present invention. DETAILED DESCRIPTION

[0046] like Figure 1 As shown, the endoscope system 10 includes an endoscope 12, a light source device 14, a processor device 16, a display 18, and a user interface 19. The endoscope 12 is optically connected to the light source device 14 and electrically connected to the processor device 16. The endoscope 12 includes: an insertion portion 12a to be inserted into a subject; an operating portion 12b provided at the base end of the insertion portion 12a; and a bending portion 12c and a front end portion 12d provided at the front end side of the insertion portion 12a. By operating the angle button 12e of the operating portion 12b, the bending portion 12c bends. As this bending movement occurs, the front end portion 12d moves in the desired direction. In addition to the illustrated keyboard, the user interface 19 also includes a mouse, etc.

[0047] In addition to the angle button 12e, the operating unit 12b is also provided with a mode switch SW13a, a still image acquisition instruction unit 13b, and a zoom operating unit 13c. The mode switch SW13a is used to switch between the single-lighting mode and the multi-lighting mode. In the single-lighting mode, normal light (specific illumination light) is emitted, and a normal image (specific observation image) is displayed on the display 18. In the multi-lighting mode, the first illumination light for emphasizing superficial blood vessels and the second illumination light for emphasizing deep blood vessels are switched according to a specific illumination pattern. Furthermore, in the multi-lighting mode, the first observation image obtained by illuminating the observation object with the first illumination light and the second observation image obtained by illuminating the observation object with the second illumination light are switched according to a specific display pattern and displayed on the display 18. In addition, in the single-lighting mode, either the first illumination light or the second illumination light may be emitted in addition to the normal light.

[0048] The still image acquisition instruction unit 13b is used to instruct the storage of a still image of the observation object in the still image storage unit 63 (see Figure 2 The zoom operation unit 13c is used to operate the zoom lens 47 and the zoom drive unit 47a provided in the endoscope 12 (see Figure 2 ).

[0049] The processor device 16 is electrically connected to a display 18 and a user interface 19. The display 18 outputs and displays image information, etc. The user interface 19 functions as a UI (User Interface) for receiving input operations such as function settings. Furthermore, an external recording unit (not shown) that records image information, etc., can be connected to the processor device 16.

[0050] like Figure 2 As shown, the light source device 14 includes a light source unit 20, a light source processor 21, and an optical path coupling unit 23. The light source unit 20 emits light of multiple wavelengths and can change the luminous ratio of the light of each wavelength. In addition, in this specification, "light of multiple different wavelengths" does not mean that the multiple wavelengths do not overlap at all, but rather that the multiple wavelengths can overlap partially. In order to emit light of multiple wavelengths, the light source unit 20 includes a V-LED (Violet Light Emitting Diode) 20a, a B-LED (Blue Light Emitting Diode) 20b, a G-LED (Green Light Emitting Diode) 20c, and an R-LED (Red Light Emitting Diode) 20d. In addition, the light source unit 20 only needs to be provided with multiple semiconductor light sources, so LD (Laser Diode) can be used instead of LED.

[0051] The light source processor 21 controls the driving of the LEDs 20a to 20d. The optical path combiner 23 combines the optical paths of the four colors of light emitted by the four LEDs 20a to 20d. The light combined by the optical path combiner 23 is irradiated into the subject via the light guide 41 and illumination lens 45 inserted into the insertion portion 12a.

[0052] like Figure 3 As shown, the V-LED 20a generates violet light V with a central wavelength of 405±10 nm and a wavelength range of 380-420 nm. The B-LED 20b generates blue light B with a central wavelength of 460±10 nm and a wavelength range of 420-500 nm. The G-LED 20c generates green light G with a wavelength range of 480-600 nm. The R-LED 20d generates red light R with a central wavelength of 620-630 nm and a wavelength range of 600-650 nm.

[0053] The light source processor 21 controls the lighting of the V-LED 20a, B-LED 20b, G-LED 20c, and R-LED 20d in any mode. In addition, in the single emission mode, the light source processor 21 controls each LED 20a to 20d so as to emit normal light in which the light intensity ratio of the purple light V, the blue light B, the green light G, and the red light R is Vc:Bc:Gc:Rc (see FIG. Figure 3 ). By photographing the object illuminated by the normal light, such as Figure 4 As shown, a normal image with emphasized surface blood vessels can be obtained. In this specification, the luminous intensity ratio refers to the light intensity ratio of each semiconductor light source, including the case where the light intensity ratio is 0 (zero). Therefore, this includes the case where any one, or two or more, of the semiconductor light sources are not turned on. For example, if the light intensity ratio of violet light V, blue light B, green light G, and red light R is 1:0:0:0, the luminous intensity ratio is also assumed to exist even when only one of the semiconductor light sources is turned on and the other three are not turned on.

[0054] Furthermore, the light source processor 21 controls each LED 20a to 20d so that the first illumination light emitted in the multi-emission mode emits the purple light V, blue light B, green light G, and red light R at a ratio of Vs1:Bs1:Gs1:Rs1. It is preferable that the first illumination light has a peak at a wavelength of 400 nm or more and 440 nm or less. Figure 5 As shown in FIG. 1 , the first illumination light is configured such that the light intensity of the purple light V is greater than the light intensity of the other blue light B, green light G, and red light R. (Vs1>Bs1, Gs1, Rs1). By photographing the object illuminated by the first illumination light, as shown in FIG. Figure 6As shown, a first observation image in which superficial blood vessels are emphasized can be obtained.

[0055] Furthermore, the first illumination light includes a first red band, such as red light R, and thus can accurately reproduce the color of the mucous membrane. Furthermore, the first illumination light includes a first blue band and a first green band, such as violet light V, blue light B, and green light G. Therefore, in addition to emphasizing the surface blood vessels as described above, various structures such as glandular duct structures and concavities and convexities are emphasized.

[0056] Furthermore, the light source processor 21 controls each of the LEDs 20a to 20d so that the second illumination light, which is emitted in the multi-emission mode, emits at a ratio of Vs2:Bs2:Gs2:Rs2 of violet light V, blue light B, green light G, and red light R. Preferably, the intensity ratio of the second illumination light at 460 nm, 540 nm, and 630 nm is increased relative to that of the first illumination light.

[0057] Therefore, if Figure 7 As shown in FIG. 1 , in the second illumination light, Vs2:Bs2:Gs2:Rs2 is set so that the light amounts of blue light B, green light G, and red light R are increased compared to the light amounts of blue light B, green light G, and red light R in the first illumination light. By photographing the observation object illuminated by the second illumination light, as shown in FIG. Figure 8 As shown, a second observation image in which the middle and deep layer blood vessels are emphasized can be obtained.

[0058] Furthermore, the ratio Vs2:Bs2:Gs2:Rs2 (Vs2 < Bs2, Gs2, Rs2) is set so that the intensity of violet light V is lower than that of blue light B, green light G, and red light R. Furthermore, the second illumination light includes a second red band, such as the red light R, enabling accurate reproduction of the color of the mucous membrane. Furthermore, the second illumination light includes a second blue band and a second green band, such as the violet light V, blue light B, and green light G. This emphasizes not only the deep blood vessels described above, but also various structures such as glandular ducts and concavities and convexities.

[0059] Furthermore, when the multi-lighting mode is set, the light source processor 21 automatically switches the first lighting light and the second lighting light according to a specific lighting pattern to control the lighting. Figure 9 As shown, as a specific light emission pattern, the first illumination light and the second illumination light are switched at intervals of two frames. Furthermore, a first observation image obtained by the emission of the first illumination light and a second observation image obtained by the emission of the second illumination light are switched at intervals of two frames and displayed on the display 18 as a specific display pattern.

[0060] like Figure 2As shown, the light guide 41 is built into the endoscope 12 and the universal cord (the cord connecting the endoscope 12, the light source device 14, and the processor device 16), and transmits the light coupled by the optical path coupling portion 23 to the distal end portion 12d of the endoscope 12. A multimode optical fiber can be used as the light guide 41. For example, a thin optical fiber cable having a core diameter of 105 μm, a cladding diameter of 125 μm, and a diameter of 0.3 to 0.5 mm including the protective layer serving as the outer sheath can be used.

[0061] The distal end portion 12d of the endoscope 12 is provided with an illumination optical system 30a and an imaging optical system 30b. The illumination optical system 30a includes an illumination lens 45, through which light from the light guide 41 is irradiated onto the object being observed. The imaging optical system 30b includes an objective lens 46, a zoom lens 47, and an imaging sensor 48. Reflected light from the object being observed is incident on the imaging sensor 48 via the objective lens 46 and the zoom lens 47. As a result, a reflected image of the object being observed is formed on the imaging sensor 48. The zoom lens 47 can be moved along the optical axis by a zoom drive unit 47a. The movement of the zoom lens 47 magnifies or reduces the object being observed. The "magnification changing unit" of the present invention corresponds to a structure including the zoom operating unit 13c, the zoom lens 47, and the zoom drive unit 47a.

[0062] The imaging sensor 48 is a color imaging sensor that captures a reflected image of the subject and outputs an image signal. The imaging sensor 48 is preferably a CCD (Charge Coupled Device) imaging sensor or a CMOS (Complementary Metal-Oxide Semiconductor) imaging sensor. The imaging sensor 48 used in the present invention is a color imaging sensor for obtaining RGB image signals of three colors: R (red), G (green), and B (blue). In other words, it is a so-called RGB imaging sensor having R pixels provided with R filters, G pixels provided with G filters, and B pixels provided with B filters.

[0063] Alternatively, the image sensor 48 may be a so-called complementary color image sensor equipped with complementary color filters for C (cyan), M (magenta), Y (yellow), and G (green), instead of an RGB color image sensor. When using a complementary color image sensor, image signals for the four colors CMYG are output. Therefore, it is necessary to convert the four CMYG image signals into three RGB image signals through complementary color-primary color conversion. Furthermore, the image sensor 48 may be a monochrome image sensor without color filters. In this case, the light source processor 21 turns on the blue light B, green light G, and red light R in a time-division manner, and synchronization processing is required during the processing of the image signals.

[0064] The image signal output from the imaging sensor 48 is sent to a CDS / AGC circuit 50. The CDS / AGC circuit 50 performs correlated double sampling (CDS) or automatic gain control (AGC) on the analog image signal. The image signal passed through the CDS / AGC circuit 50 is converted into a digital image signal by an A / D converter (A / D (Analog / Digital) converter) 52. The A / D-converted digital image signal is input to the processor device 16.

[0065] In the processor device 16, programs related to processes such as automatic mode switching are stored in a program memory (not shown). In the processor device 16, the programs in the program memory are executed by a central control unit 68, which is composed of an image control processor, thereby realizing the functions of the image acquisition unit 53, DSP (Digital Signal Processor) 56, noise reduction unit 58, image processing unit 60, parameter switching unit 62, display control unit 66, and automatic mode switching unit 69.

[0066] The image acquisition unit 53 receives a digital color image signal from the endoscope 12. The color image signal is an RGB image signal composed of an R image signal output from an R pixel of the imaging sensor 48, a G image signal output from a G pixel of the imaging sensor 48, and a B image signal output from a B pixel of the imaging sensor 48.

[0067] The DSP 56 performs various signal processing on the received image signals, including defect correction, offset processing, gain processing, color adjustment processing, gamma conversion processing, and demosaicing processing. Defect correction corrects signals from defective pixels in the imaging sensor 48. Offset processing removes dark current components from the defect-corrected RGB image signals, thereby setting an accurate zero level.

[0068] In gain processing, the RGB image signals after offset processing are multiplied by a specific gain parameter to adjust the signal level. The specific gain parameter varies for each mode. For example, in the case of single-light mode, normal light gain processing is performed on the image signal obtained by illumination and imaging with normal light, which is a specific gain parameter multiplied by the normal light gain parameter. Furthermore, in the case of multi-light mode, when the first illumination light is illuminated, the RGB image signals obtained by illumination and imaging with the first illumination light are subjected to first illumination light gain processing, which is a specific gain parameter multiplied by the first illumination light gain parameter. Furthermore, when the second illumination light is illuminated, the RGB image signals obtained by illumination and imaging with the second illumination light are subjected to second illumination light gain processing, which is a specific gain parameter multiplied by the second illumination light gain parameter.

[0069] Afterwards, gamma conversion is performed to adjust brightness and chroma. De-mosaicing (also known as isotropic processing or synchronization) is performed on the RGB image signal after linear matrix processing, and signals for the colors missing in each pixel are generated through interpolation. This demosaicing process ensures that all pixels have signals for each RGB color.

[0070] The noise removal unit 58 removes noise from the RGB image signals by performing noise removal processing (eg, moving average or median filtering) on ​​the RGB image signals that have been subjected to gamma correction and the like in the DSP 56. The noise-removed RGB image signals are sent to the image processing unit 60.

[0071] The image processing unit 60 performs various image processing on the RGB image signal. Among the various image processing, in addition to image processing performed under the same conditions regardless of the single-light emission mode or the multi-light emission mode, there is also image processing performed under different conditions in each mode. The image processing performed under different conditions in each mode includes color adjustment processing for improving color reproducibility and structure emphasis processing for emphasizing various structures such as blood vessels and bumps. The color adjustment processing and structure emphasis processing are processing using a two-dimensional LUT (Look Up Table), a three-dimensional LUT (Look Up Table) or a matrix. In the image processing unit 60, when performing color emphasis processing and structure emphasis processing, color emphasis processing parameters and structure emphasis processing parameters set for each mode are used. Switching of these color emphasis processing parameters or structure emphasis processing parameters is performed by the parameter switching unit 62.

[0072] When the image processing unit 60 is set to single-light emission mode, the parameter switching unit 62 switches between normal light color emphasis processing parameters and normal light structure emphasis processing parameters. Normal light color emphasis processing is then performed on the RGB image signal using the normal light color emphasis processing parameters, and normal light structure emphasis processing is then performed on the RGB image signal using the normal light structure emphasis processing parameters. The RGB image signal, having undergone these processing steps, is then input to the display control unit 66 as a normal image.

[0073] When the image processing unit 60 is set to the multi-lighting mode, during illumination with the first illumination light, the image processing unit 60 performs color emphasis processing for the first illumination light and structure emphasis processing for the first illumination light on the RGB image signal. The RGB image signal after the above processing is then input to the display control unit 66 as the first observation image. Furthermore, during illumination with the second illumination light, the RGB image signal is subjected to color emphasis processing for the second illumination light and structure emphasis processing for the second illumination light. Furthermore, when the image processing unit 60 is set to the multi-lighting mode, it performs mucosa color balancing processing to ensure that the color of the normal mucosa included in the observation object is the same between the first observation image and the second observation image. The first mucosa color balancing processing is performed on the first observation image, and the second mucosa color balancing processing based on the result of the first mucosa color balancing processing is performed on the second observation image. The RGB image signal after the above processing is then input to the display control unit 66 as the second observation image.

[0074] Furthermore, regarding the first mucous membrane color balance processing, the B1 image signal, G1 image signal, and R1 image signal included in the first observation image are automatically adjusted so that the average color of the entire screen reaches a specific color balance, as shown in, for example, D1) to D3) below. This first mucous membrane color balance processing is performed assuming that the color of the mucous membrane is dominant in the observation object. Then, by performing the first mucous membrane color balance processing, a B1 image that has undergone the first mucous membrane color balance processing can be obtained. * Image signal, G1 * Image signal, R1 * Image signal.

[0075] D1)B1 * Image signal = B1 / Blave

[0076] D2)G1 * Image signal = G1 / Glave

[0077] D3)R1 * Image signal = R1 / Rlave

[0078] Here, "Blave" represents the average pixel value of the B1 image signal (the sum of the pixel values ​​of the entire screen (effective pixels) / the number of effective pixels). "Glave" represents the average pixel value of the G1 image signal (the sum of the pixel values ​​of the entire screen (effective pixels) / the number of effective pixels). "Rlave" represents the average pixel value of the R1 image signal (the sum of the pixel values ​​of the entire screen (effective pixels) / the number of effective pixels).

[0079] Furthermore, regarding the second mucosal color balance processing, the B2 image signal, G2 image signal, and R2 image signal included in the second observation image are automatically adjusted so that the average color of the entire screen reaches a specific color balance, as shown in, for example, E1) to E3) below. In this second mucosal color balance processing, the Blave, Glave, and Rlave calculated by the first mucosal color balance processing are used. Then, by performing the second mucosal color balance processing, the B2 image signal that has undergone the second mucosal color balance processing can be obtained. * Image signal, G2 * Image signal, R2 * Image signal.

[0080] E1)B2 * Image signal = B2 / Blave

[0081] E2)G2 * Image signal = G2 / Glave

[0082] E3)R2 * Image signal = R2 / Rlave

[0083] The display control unit 66 controls the normal image, the first observation image, or the second observation image input from the image processing unit 60 to be displayed as an image that can be displayed on the display 18. In the case of the single-light emission mode, the display control unit 66 displays the normal image on the display 18. In the case of the multi-light emission mode, the display control unit 66 controls the normal image according to a specific display pattern (in this embodiment, "two-frame interval". Figure 9 . ), while switching between the first observation image and the second observation image, it is displayed on the display 18.

[0084] As described above, in addition to executing programs, the central control unit 68 also controls the various components of the processor device 16. Furthermore, the central control unit 68 receives information from the endoscope 12 or the light source device 14 and controls the various components of the processor device 16 and the endoscope 12 or the light source device 14 based on the received information.

[0085] When the mode automatic switching unit 69 is set to the multi-lighting mode and the pre-set single-lighting switching condition is met, such as Figure 10As shown, the process switches from the multi-lighting mode, in which the first and second observation images are switched and displayed on the display 18, to the single-lighting mode, in which only the normal image is continuously displayed on the display 18. This automatic mode switching is enabled because, for example, when the observation object barely changes, the operator may forget to switch modes. Furthermore, it can be difficult for the operator to know whether the multi-lighting mode or the single-lighting mode is set. Therefore, in the multi-lighting mode, the display 18 displays "multi-lighting mode"; in the single-lighting mode, the display 18 displays "single-lighting mode."

[0086] As a single light switching condition for switching from the multi-light mode to the single light mode, for example, the time of use of the multi-light mode becomes equal to or greater than a preset time threshold. In this case, the time measurement unit (not shown) provided in the processor device 16 measures the time after the mode switch SW13a is set to the multi-light mode. Then, when the measured time becomes equal to or greater than the time threshold, the time measurement unit 16 measures the time after the mode switch SW13a is set to the multi-light mode. Figure 11 As shown, it automatically switches from multi-lighting mode to single-lighting mode.

[0087] Furthermore, as a single light switching condition, for example, the number of times the still image of the observation object is saved becomes greater than a preset number threshold. At this time, the number of times the still image acquisition instruction unit 13b is operated is counted in a number counting unit (not shown) provided in the processor device 16. Then, when the counted number of times becomes greater than the number threshold, the still image acquisition instruction unit 13b is switched. Figure 12 As shown, it automatically switches from multi-lighting mode to single-lighting mode.

[0088] Furthermore, as the single emission switching condition, it is assumed that the imaging condition related to the observation object changes. In this case, in order to obtain the imaging condition, an imaging condition acquisition unit 70 is provided in the image processing unit 60 of the processor device 16. Figure 13 As shown, the imaging condition acquisition unit 70 includes an observation site acquisition unit 72 , a brightness calculation unit 74 , a magnification acquisition unit 76 , an observation distance acquisition unit 78 , and a blur amount calculation unit 80 .

[0089] As a single light switching condition, when the observation part as one of the imaging conditions changes, for example, when the observation part currently being imaged changes from the first part (for example, "esophagus") to the second part (for example, "stomach") or from the second part to the first part, Figure 14 When the observation part changes, it is considered that the distal end portion 12d of the endoscope is moving, and sometimes the first illumination light or the second illumination light that is alternately emitted cannot reliably illuminate the observation object. In such a case, the multi-illumination mode is not suitable.

[0090] The observation site acquisition unit 72 acquires information related to the observation site. The observation site acquisition unit 72 determines the observation site based on the image features of the first or second observation image obtained in multi-lighting mode. For example, if the brightness of the center of the image in the first or second observation image is darker than that of the surrounding areas, the observation site is determined to be the "esophagus." Alternatively, if the brightness of the center of the image in the first or second observation image is brighter than that of the surrounding areas, the observation site is determined to be the "stomach."

[0091] As a single light emission switching condition, when the brightness of the observation object as one of the photographing conditions becomes below the first brightness threshold or above the second brightness threshold which is larger than the first brightness threshold, Figure 15 As shown, the multi-lighting mode is automatically switched to the single-lighting mode. When the brightness is below the first brightness threshold, the entire observation object is dark, making it unsuitable for the multi-lighting mode. Similarly, when the brightness is above the second brightness threshold, the entire observation object is extremely bright, such as when a halo is generated, making it unsuitable for the multi-lighting mode. In addition, information related to brightness is obtained in the brightness calculation unit 74. The brightness calculation unit 74 calculates the average value of pixel values ​​based on the first observation image or the second observation image, and calculates the brightness based on the calculated average value of pixel values. Here, the larger the average value of pixel values, the greater the brightness.

[0092] As a single emission switching condition, when the magnification change amount exceeds the magnification threshold value regarding the magnification of the observation object as one of the imaging conditions, such as Figure 16 As shown, the multi-lighting mode automatically switches to the single-lighting mode. If the magnification of the observation object changes significantly and the magnification change exceeds the magnification threshold, the illumination distribution of the illumination light relative to the observation object changes, making the multi-lighting mode unsuitable. Furthermore, each time the zoom operation unit 13c is operated, zoom information indicating the magnification set is transmitted to the magnification acquisition unit 76. The automatic mode switching unit 69 refers to the zoom information acquired by the magnification acquisition unit 76 to determine whether the magnification change exceeds the magnification threshold.

[0093] As a single light switching condition, regarding the observation distance (the distance between the distal end portion 12d of the endoscope and the observation object) as one of the imaging conditions, when the change in the observation distance exceeds the distance threshold, Figure 17As shown, the camera automatically switches from multi-lighting mode to single-lighting mode. Similar to the magnification of the observed object, if the observation distance changes significantly and the change in observation distance exceeds the distance threshold, the illumination distribution relative to the observed object changes, making multi-lighting mode unsuitable. Furthermore, regarding the observation distance, the observation distance acquisition unit 78 calculates the average pixel value from the first or second observation image obtained in multi-lighting mode, and calculates the observation distance based on the calculated average pixel value. The larger the average pixel value, the smaller the observation distance.

[0094] As a single emission switching condition, when the blur amount of the image as one of the photographing conditions exceeds the blur amount threshold, such as Figure 18 As shown, the multi-lighting mode is automatically switched to the single-lighting mode. When the blur amount of the image is large and the blur amount exceeds the blur amount threshold, the illumination light may not be reliably irradiated on the observation object, which is usually not suitable for the multi-lighting mode. In addition, regarding the blur amount, the blur amount calculation unit 80 calculates the contrast based on the first observation image or the second observation image obtained in the multi-lighting mode, and calculates the blur amount based on the contrast. The lower the contrast, the greater the blur amount. As a method for calculating the blur amount, in addition to using the contrast, it can also be calculated based on the frequency component of the first observation image or the second observation image (the lower the frequency component, the greater the blur amount).

[0095] As described above, the operator can appropriately set the single light switching condition for automatically switching from the multi-light mode to the single light mode. Figure 19 The single-emission switching condition setting menu 82 is displayed on the display 18. In this single-emission switching condition setting menu 82, you can set a "time threshold" and a "number threshold." If the "time threshold" is set to "100 seconds" in the single-emission switching condition setting menu 82, the system automatically switches from multi-emission mode to single-emission mode when the multi-emission mode usage time reaches "100 seconds." Furthermore, if the "number threshold" is set to "40 times" in the single-emission switching condition setting menu 82, the system automatically switches from multi-emission mode to single-emission mode when the still image acquisition instruction unit 13b has been operated 40 times.

[0096] In addition, as described later, regarding the multi-light restart conditions for automatic switching from single-light mode to multi-light mode, it is preferred to display the multi-light restart condition setting menu that is the same as the single-light switching condition setting menu 82 on the display 18 so that appropriate settings can be made.

[0097] Furthermore, in the single-light switching condition setting menu 82, it is possible to set the "1st part" and "2nd part." If the "1st part" is set to "esophagus" and the "2nd part" is set to "stomach," the multi-light mode automatically switches to the single-light mode when the observation part changes from "esophagus" to "stomach," or vice versa. Furthermore, in the single-light switching condition setting menu 82, it is possible to set the "1st brightness threshold" and "2nd brightness threshold." If the "1st brightness threshold" is set to P1 and the "2nd brightness threshold" is set to P2 (>P1), the multi-light mode automatically switches to the single-light mode when the brightness of the observation object falls below P1 or exceeds P2.

[0098] Furthermore, in the single-light switching condition setting menu 82, it is possible to set the "threshold value for magnification". When the "threshold value for magnification" is set to "5 times", when the magnification change of the observed object exceeds "5 times", the multi-light mode is automatically switched to the single-light mode. Furthermore, in the single-light switching condition setting menu 82, it is possible to set the "threshold value for distance". When the "threshold value for distance" is set to Lx, when the change in the observed distance exceeds Lx, the multi-light mode is automatically switched to the single-light mode. Furthermore, in the single-light switching condition setting menu 82, it is possible to set the "threshold value for blur amount". When the "threshold value for blur amount" is set to Br, when the blur amount exceeds Br, the multi-light mode is automatically switched to the single-light mode.

[0099] When the mode automatic switching unit 69 automatically switches from the multi-emission mode to the single-emission mode by satisfying the single-emission switching condition, as shown in FIG. Figure 20 As shown, when a pre-set multi-lighting restart condition is met, the single-lighting mode is automatically switched to the multi-lighting mode. Automatic switching to the single-lighting mode occurs when, for example, the imaging conditions related to the observed object change. However, automatic switching from the single-lighting mode to the multi-lighting mode is preferred when, for example, the change in the imaging conditions related to the observed object is within an acceptable range and the multi-lighting restart condition is met. Furthermore, the change in imaging conditions within an acceptable range means that the change in imaging conditions does not affect the visual recognition of the switched display of the first and second observation images obtained in the multi-lighting mode.

[0100] The preferred multi-light re-start condition is that the observation object changes from the first site (e.g., "esophagus") to the second site (e.g., "stomach") and then returns to the first site within a predetermined time, or changes from the second site to the first site and then returns to the second site within a predetermined time. Figure 21As shown, the single-lighting mode automatically switches to the multi-lighting mode. This is because when the observation area is immediately returned to the original area, the lighting conditions barely change, and the lighting state based on the multi-lighting mode is not affected. Furthermore, similarly to the above, information related to the observation area is acquired by the observation area acquisition unit 72.

[0101] The multi-light re-start condition is preferably when the brightness of the observation object becomes greater than or equal to the first brightness threshold or less than or equal to the second brightness threshold which is greater than the first brightness threshold. Figure 22 As shown, the single-lighting mode automatically switches to the multi-lighting mode. This is because even if the brightness decreases or increases, returning to the original normal brightness (above the first brightness threshold or below the second brightness threshold that is greater than the first brightness threshold) after a predetermined time does not affect the lighting state based on the multi-lighting mode. Furthermore, as described above, information related to brightness is obtained in the brightness calculation unit 74.

[0102] The multi-light emission restart condition is preferably that when the magnification of the observation object is changed, the magnification change amount of the observation object is less than the magnification threshold. Figure 23 As shown, the single-emission mode automatically switches to the multi-emission mode. This is because the magnification change of the observation object is not significant, and the magnification change temporarily exceeding the magnification threshold and then immediately falling below the magnification threshold does not affect the illumination state based on the multi-emission mode. Furthermore, the magnification acquisition unit 76 acquires the magnification of the observation object in the same manner as described above.

[0103] The multi-lighting restart condition is preferably when the change in the observation distance becomes less than the distance threshold. Figure 24 As shown, the single-lighting mode automatically switches to the multi-lighting mode. This is because the change in observation distance is not significant. When the change in observation distance temporarily exceeds the distance threshold and then immediately falls below it, it does not affect the lighting state in the multi-lighting mode. Furthermore, the observation distance is acquired by the observation distance acquisition unit 78 in the same manner as described above.

[0104] The multi-light emission restart condition is preferably when the blur amount of the observed image becomes less than the blur amount threshold. Figure 25 As shown, the image automatically switches from single-emission mode to multi-emission mode. This is because the image blur is not significant, and if the blur temporarily exceeds the distance threshold and then immediately falls below the blur threshold, it will not affect the illumination state in the multi-emission mode. Furthermore, the blur amount calculation unit 80 calculates the blur amount in the same manner as described above.

[0105] However, in order to prevent the situation where the multi-lighting mode is automatically switched to automatically by accident, the mode automatic switching unit 69 preferably performs the following processing: when the multi-lighting restart condition and the restart permission condition are satisfied, the single-lighting mode is automatically switched to the multi-lighting mode, and when the multi-lighting restart condition is satisfied and the restart permission condition is not satisfied, the automatic switching to the multi-lighting mode is prohibited. The restart permission condition is preferably set by the operator. And, in order to determine whether the restart permission condition is satisfied, a restart permission flag indicating the restart permission condition is used. A restart permission flag of "1" indicates that the restart permission condition is satisfied, and a restart permission flag of "0" indicates that the restart permission condition is not satisfied (refer to Figures 20 to 25 ).

[0106] The restart permission condition is preferably when the operator has not selected the single-emission mode. The single-emission mode is preferably selected by operating the user interface 19. When the operator has selected the single-emission mode, the restart permission flag is set to "0." When the operator has not selected the single-emission mode, the restart permission flag is set to "1." When the operator voluntarily selects the single-emission mode, the system preferably does not automatically switch to the multi-emission mode.

[0107] The restart permission condition is preferably a case where the restart permission time has not passed after the single-light-emission switching condition is satisfied and the multi-light-emission mode is automatically switched to the single-light-emission mode. In this case, the time measurement unit (not shown) measures the time after switching to the single-light-emission mode. When the measured time does not pass the restart permission time, the restart permission flag remains at "1". Then, when the measured time passes the restart permission time, the restart permission flag is switched to "0". It is considered that after the restart permission time has passed, the state is suitable for observation based on the single-light-emission mode, so it is preferred not to automatically switch to the multi-light-emission mode.

[0108] The restart permission condition is preferably a case where the multi-lighting mode can be implemented. The judgment on whether the multi-lighting mode can be implemented is performed by the multi-lighting mode implementation judgment unit (not shown) of the processor device 16. Specifically, the multi-lighting mode implementation judgment unit detects abnormalities related to the endoscope 12, the light source device 14 and the processor device 16, and determines whether the multi-lighting mode can be implemented based on the detection result. At this time, when the multi-lighting mode implementation judgment unit determines that the multi-lighting mode can be implemented, the restart permission flag is set to "1", and when it is determined that the multi-lighting mode cannot be implemented, the restart permission flag is set to "0". When an abnormality related to the endoscope 12, the light source device 14 and the processor device 16 occurs and it is difficult to implement the multi-lighting mode, it is preferable not to automatically switch to the multi-lighting mode.

[0109] The restart permission condition is preferably a case where the use or non-use switching of the magnification change unit is not performed. The use of the magnification change unit refers to a state where the magnification can be changed by setting the zoom operation unit 13c to "ON". The non-use of the magnification change unit refers to a state where the magnification is not changed by setting the zoom operation unit 13c to "OFF". At this time, after the single-light switching condition is satisfied and the single-light mode is automatically switched, if there is no switch to use or non-use of the magnification change unit, the restart permission flag is set to "1", and if the use or non-use of the magnification change unit is switched, the restart permission flag is set to "0". When the use or non-use switching of the magnification change unit is performed, the multi-light mode is not necessarily always used when observing an object different from the previous multi-light mode situation, so it is preferable not to automatically switch to the multi-light mode.

[0110] Then, along Figure 26 The flowchart shown illustrates a series of processes encompassing the present invention. In multi-lighting mode, the first and second illumination lights are switched and emitted according to a specific illumination pattern (in this embodiment, a two-frame interval). Furthermore, according to a specific display pattern (in this embodiment, a two-frame interval), a first observation image obtained by capturing the observation object illuminated by the first illumination light and a second observation image obtained by capturing the observation object illuminated by the second illumination light are switched and displayed on the display 18.

[0111] Furthermore, when a pre-set single-light switching condition is met, the multi-light mode is automatically switched to the single-light mode. Single-light switching conditions include situations where the multi-light mode usage time exceeds a time threshold, and situations where the number of still image saves exceeds a number threshold. Furthermore, single-light switching conditions include situations where photographic conditions related to the observed object change. If the single-light mode is automatically switched to, the switching of the first and second illumination lights is stopped. Simultaneously, the switching display of the first and second observation images is also stopped. Then, normal light is emitted, and a normal image obtained by photographing the observed object illuminated by the normal light is displayed on the display 18.

[0112] After automatically switching to single-lighting mode, the processor device 16 monitors whether the multi-lighting restart condition is satisfied. When both the multi-lighting restart condition and the restart permission condition are satisfied, the single-lighting mode is automatically switched to the multi-lighting mode. On the other hand, even if the multi-lighting restart condition is satisfied, if the restart permission condition is not satisfied, the automatic switch to the multi-lighting mode is prohibited. Furthermore, if the multi-lighting restart condition is not satisfied, the automatic switch to the multi-lighting mode is also prohibited. When automatic switching to the multi-lighting mode is prohibited, the single-lighting mode is maintained.

[0113] In addition, in the above-mentioned embodiment, light is emitted while switching the first illumination light and the second illumination light according to a specific illumination pattern, and the first observation image corresponding to the first illumination light and the second observation image corresponding to the second illumination light are switched according to a specific display pattern and displayed on the display 18. However, it is also possible to emit light while switching more than three types of illumination lights with different wavelengths according to a specific illumination pattern, and switch more than three types of observation images corresponding to each illumination light according to a specific display pattern and display them on the display 18.

[0114] In the above-described embodiment, the hardware configuration of the processing units included in the processor device 16, such as the image acquisition unit 53, DSP 56, noise removal unit 58, image processing unit 60, parameter switching unit 62, central control unit 68, and automatic mode switching unit 69, is composed of the various processors shown below. These processors include general-purpose processors such as CPUs (Central Processing Units) that execute software (programs) to function as various processing units; processors such as FPGAs (Field Programmable Gate Arrays) whose circuit configuration can be modified after manufacturing, such as programmable logic devices (PLDs); and processors with circuit configurations specifically designed to execute various processes, such as dedicated circuits.

[0115] 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 or a CPU and an FPGA). In addition, multiple processing units may be composed of one processor. As an example of a method in which multiple processing units are composed of one processor, there is a method in which a processor is composed of a combination of one or more CPUs and software, such as a client computer and a server computer, and the processor functions as multiple processing units. There is a method in which a processor is used to realize the functions of the entire system including multiple processing units through one IC (Integrated Circuit) chip, such as a system on chip (SoC). In this way, various processing units are composed of one or more of the above-mentioned various processors as a hardware structure.

[0116] Furthermore, as the hardware configuration of these various processors, more specifically, a circuit in a form of a combination of circuit elements such as semiconductor elements can be used.

[0117] Explanation of symbols

[0118] 10-Endoscope system, 12-Endoscope, 12a-Insertion portion, 12b-Operation portion, 12c-Bending portion, 12d-Front end portion, 12e-Angle button, 13a-Mode switching switch, 13b-Still image acquisition instruction portion, 13c-Zoom operation portion, 14-Light source device, 16-Processor device, 18-Display, 19-User interface, 20-Light source portion, 20a-V-LED (Violet Light Emitting Diode), 20b-B-LED (Blue Light Emitting Diode), 20c-G-LED (Green Light Emitting Diode), 20d-R-LED (Red Light Emitting Diode) Diode), 21- processor for light source, 23- optical path coupling unit, 30a- illumination optical system, 30b- imaging optical system, 41- light guide, 45- illumination lens, 46- objective lens, 47- zoom lens, 47a- zoom drive unit, 48- imaging sensor, 50- CDS / AGC circuit, 52- A / D converter, 53- image acquisition unit, 56- DSP (Digital Signal Processor), 58- noise reduction unit, 60- image processing unit, 62- parameter switching unit, 63- still image storage unit, 66- display control unit, 68- central control unit, 69- automatic mode switching unit, 70- photographing condition acquisition unit, 72- observation part acquisition unit, 74- brightness calculation unit, 76- magnification acquisition unit, 78- observation distance acquisition unit, 80- blur amount calculation unit, 82- single light emission switching condition setting menu.

Claims

1. An endoscope system comprising: Multiple semiconductor light sources emit light in different wavelength bands; a light source processor for controlling the plurality of semiconductor light sources to perform control related to a single light emission mode in which only a specific illumination light having a specific light emission ratio is emitted, and a multi-light emission mode in which multiple illumination lights including a first illumination light having a first light emission ratio and a second illumination light having a second light emission ratio different from the first light emission ratio are switched while emitting light according to a specific light emission pattern; and Image control processor, The image control processor performs the following processing: When the multi-lighting mode is automatically switched to the single-lighting mode by satisfying a preset single-lighting switching condition, When the pre-set multi-lighting restart condition and the restart permission condition are satisfied, the single-lighting mode is automatically switched to the multi-lighting mode. When the multi-light emission restart condition is satisfied and the restart permission condition is not satisfied, automatic switching to the multi-light emission mode is prohibited.

2. The endoscope system according to claim 1, wherein: The restart permission condition is a case where the operator has not selected the single light emission mode.

3. The endoscope system according to claim 1, wherein: The restart permission condition is a case where the restart permission time has not elapsed after switching to the single light emission mode.

4. The endoscope system according to claim 2, wherein: The restart permission condition is a case where the restart permission time has not elapsed after switching to the single light emission mode.

5. The endoscope system according to claim 1, wherein: The restart permission condition is a condition where the multi-light emission mode can be implemented.

6. The endoscope system according to claim 2, wherein: The restart permission condition is a condition where the multi-light emission mode can be implemented.

7. The endoscope system according to claim 3, wherein: The restart permission condition is a condition where the multi-light emission mode can be implemented.

8. The endoscope system according to claim 1, wherein: The endoscope system includes a magnification changing unit for changing the magnification of an observation object. The restart permission condition is that the switching between use and non-use of the magnification changing unit has not been performed.

9. The endoscope system according to claim 2, wherein: The endoscope system includes a magnification changing unit for changing the magnification of an observation object. The restart permission condition is that the switching between use and non-use of the magnification changing unit has not been performed.

10. The endoscope system according to claim 3, wherein: The endoscope system includes a magnification changing unit for changing the magnification of an observation object. The restart permission condition is that the switching between use and non-use of the magnification changing unit has not been performed.

11. The endoscope system according to claim 5, wherein: The endoscope system includes a magnification changing unit for changing the magnification of an observation object. The restart permission condition is that the switching between use and non-use of the magnification changing unit has not been performed.

12. The endoscope system according to claim 1, wherein: The restart permission condition can be set by an operator.

13. The endoscope system according to claim 2, wherein: The restart permission condition can be set by an operator.

14. The endoscope system according to claim 3, wherein: The restart permission condition can be set by an operator.

15. The endoscope system according to claim 5, wherein: The restart permission condition can be set by an operator.

16. The endoscope system according to claim 8, wherein: The restart permission condition can be set by an operator.

17. The endoscope system according to any one of claims 1 to 16, wherein: The multi-light emission restart condition is that a change in imaging conditions related to the observation object is within an allowable range.

18. The endoscope system according to claim 17, wherein: The multi-light emission restart condition is a condition formed by combining at least one of the following conditions: The observation object changes from the first site to the second site and then returns to the first site within a predetermined time, or changes from the second site to the first site and then returns to the second site within a predetermined time; When the brightness of the observation object becomes equal to or higher than a first brightness threshold or equal to or lower than a second brightness threshold that is greater than the first brightness threshold; When the magnification of the observation object is changed, the amount of change in the magnification of the observation object becomes smaller than a magnification threshold value; When the change in the observed distance becomes less than the distance threshold; and When the blur amount of the observation image obtained by imaging the observation object is equal to or less than the blur amount threshold value.

19. The endoscope system according to any one of claims 1 to 16, wherein: The image control processor performs the following processing: In the case of the single illumination mode, control is performed to display a specific observation image obtained by photographing the observation object illuminated by the specific illumination light on the display. In the case of the multi-illumination mode, control is performed to switch a plurality of observation images including a first observation image obtained by photographing the observation object illuminated by the first illumination light and a second observation image obtained by photographing the observation object illuminated by the second illumination light according to a specific display style and display them on the display.

20. The endoscope system according to claim 17, wherein: The image control processor performs the following processing: In the case of the single illumination mode, control is performed to display a specific observation image obtained by photographing the observation object illuminated by the specific illumination light on the display. In the case of the multi-illumination mode, control is performed to switch a plurality of observation images including a first observation image obtained by photographing the observation object illuminated by the first illumination light and a second observation image obtained by photographing the observation object illuminated by the second illumination light according to a specific display style and display them on the display.

21. The endoscope system according to claim 18, wherein The image control processor performs the following processing: In the case of the single illumination mode, control is performed to display a specific observation image obtained by photographing the observation object illuminated by the specific illumination light on the display. In the case of the multi-illumination mode, control is performed to switch a plurality of observation images including a first observation image obtained by photographing the observation object illuminated by the first illumination light and a second observation image obtained by photographing the observation object illuminated by the second illumination light according to a specific display style and display them on the display.

22. A method for operating an endoscope system, the endoscope system comprising: Multiple semiconductor light sources emit light in different wavelength bands; a light source processor for controlling the plurality of semiconductor light sources to perform control related to a single light emission mode in which only a specific illumination light having a specific light emission ratio is emitted, and a multi-light emission mode in which multiple illumination lights including a first illumination light having a first light emission ratio and a second illumination light having a second light emission ratio different from the first light emission ratio are switched while emitting light according to a specific light emission pattern; and Image control processor, In the operating method of the endoscope system, The image control processor performs the following processing: When the pre-set single-lighting switching condition is met and the multi-lighting mode is automatically switched to the single-lighting mode, When the pre-set multi-lighting restart condition and the restart permission condition are satisfied, the single-lighting mode is automatically switched to the multi-lighting mode. When the multi-light emission restart condition is satisfied and the restart permission condition is not satisfied, automatic switching to the multi-light emission mode is prohibited.

Images