Endoscope system and method of operation thereof

Abstract

To provide: an endoscope system which changes an imaging driving system of an imaging sensor without complicating a system; and an operation method of the endoscope system.SOLUTION: In a case of not changing an imaging drive method, a scope logic circuit 28b outputs a frame signal outputted from an imaging sensor 26 through imaging of an observation object and a synchronization signal, to a processor device 14. In a case of changing the imaging drive method in response to a sensor switch request, the scope logic circuit 28b outputs a dummy signal different from the frame signal and generated artificially and a synchronization signal, to the processor device 14.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to an endoscope system having a plurality of imaging drive methods and an operation method thereof. [Background technology]

[0002] In the field of endoscopy, it is becoming common to illuminate and image an object to be observed using multiple types of illumination light, such as normal light and special light. For example, in Patent Document 1, when normal light is continuously irradiated for a first period and then special light is irradiated for a second period, the frame rate of an imaging unit that captures images based on each illumination is set higher than the frame rate of a display unit that displays the images obtained by the imaging. As a result, Patent Document 1 displays high-quality live images based on imaging using normal light while performing imaging using special light. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2021 / 177330 Summary of the Invention [Problem to be solved by the invention]

[0004] As described in Patent Document 1, endoscope systems are currently implementing two imaging control methods: normal frame rate imaging, in which the frame rate of the imaging unit is the same as that of the display unit, and high frame rate imaging, in which the frame rate of the imaging unit is higher than that of the display unit. For example, when switching from normal frame rate imaging to high frame rate imaging, the imaging sensor must be temporarily put into standby mode to change the imaging drive method, such as the frame rate. In this case, the imaging sensor temporarily stops generating not only the frame signals obtained by imaging, but also the synchronization signals generated in conjunction with the frame signals.

[0005] On the other hand, endoscope systems perform light emission control, signal processing, display control, and the like based on synchronization signals, and are also provided with an abnormality detection function that checks for abnormalities in the control or processing based on the synchronization signals. Therefore, as described above, since generation of the synchronization signal stops when the imaging drive method is changed, it is conceivable to disable the abnormality detection function. However, disabling the abnormality detection function requires not only disabling but also enabling processing after the imaging drive method is set, which increases the time required to disable and enable the abnormality detection function, resulting in a complex system. Furthermore, if the imaging sensor's image is stopped and the image is resumed at each processing unit by a method other than the synchronization signal when the imaging drive method is changed, the system also becomes complex.

[0006] An object of the present invention is to provide an endoscope system and an operation method thereof that change the imaging drive method of an image sensor without complicating the system. [Means for solving the problem]

[0007] The endoscopic system of the present invention comprises an endoscope having an imaging sensor and a scope processor, and a processor device having a system processor, wherein the system processor issues a sensor switching request to the scope processor to change the imaging drive method of the imaging sensor, and either the scope processor or the system processor, when the imaging drive method is not to be changed, images the object to be observed and outputs a frame signal and a synchronization signal output from the imaging sensor to the processor device, and when the imaging drive method is to be changed in accordance with the sensor switching request, outputs an artificially generated dummy signal and a synchronization signal which are different from the frame signal to the processor device.

[0008] It is preferable that a dummy signal identifier is assigned to the dummy signal. When there is no dummy signal identifier, either the scope processor or the system processor identifies the signal as a frame signal before switching of the imaging drive method or a frame signal after switching of the imaging drive method, and when there is a dummy signal identifier, it identifies the signal as a dummy signal during switching of the imaging drive method.

[0009] The system processor preferably stops updating of the image displayed on the display when it identifies the signal as a dummy signal. The system processor preferably sets image processing parameters to be used after changing the imaging drive method when it identifies the signal as a dummy signal. The system processor preferably temporarily switches the light source control algorithm to a light source control algorithm during dummy signal identification when it identifies the signal as a dummy signal. The algorithm during dummy signal identification preferably includes generating light source control information used to calculate a target light intensity based on the frame signal immediately before identifying the dummy signal.

[0010] The system processor preferably executes a light source control algorithm based on a frame signal obtained after identifying the frame signal at a timing when the system processor identifies a frame signal after identifying the dummy signal, and preferably resumes updating of an image on the display based on a frame signal obtained after identifying the frame signal at a timing when the system processor identifies a frame signal after identifying the dummy signal.

[0011] The dummy signal preferably includes a dummy identification image.The system processor preferably performs an anomaly detection function based on the synchronization signal.

[0012] The present invention provides a method for operating an endoscopic system including an endoscope having an imaging sensor and a scope processor, and a processor device having a system processor, the method comprising the steps of: the system processor issuing a sensor switching request to the scope processor to change the imaging drive method of the imaging sensor; and, if either the scope processor or the system processor does not change the imaging drive method, imaging an object to be observed and outputting a frame signal and a synchronization signal output from the imaging sensor to the processor device; and, if the imaging drive method is to be changed in accordance with the sensor switching request, outputting an artificially generated dummy signal and a synchronization signal that are different from the frame signal to the processor device. [Effects of the Invention]

[0013] According to the present invention, the imaging drive method of the image sensor can be changed without complicating the system. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is an external view of an endoscope system. [Figure 2] FIG. 2 is a block diagram showing the functions of the endoscope system. [Figure 3] FIG. 10 is an image diagram showing a display mode in multi-flash mode. [Figure 4] FIG. 2 is an explanatory diagram illustrating an image sensor. [Figure 5] 10A is an explanatory diagram showing light emission control and imaging control in mono light emission mode, and FIG. 10B is an explanatory diagram showing light emission control and imaging control in multi light emission mode. [Figure 6] FIG. 2 is a block diagram showing the functions of an endoscope system used to explain various processes when an imaging drive method is changed. [Figure 7] 10 is an explanatory diagram showing the control of the endoscope and the processor device when switching from the mono-emission mode to the multi-emission mode. FIG. [Figure 8] FIG. 10 is an explanatory diagram showing a dummy signal to which a dummy signal identifier is assigned. [Figure 9]FIG. 10 is an explanatory diagram showing a dummy signal including a dummy identification image. [Figure 10] 10 is a flowchart showing a series of steps for changing the imaging drive method of the image sensor. [Figure 11] 1A is an explanatory diagram showing light emission control and imaging control in mono light emission mode, and FIG. 1B is an explanatory diagram showing light emission control and imaging control in multi-color intermittent light emission mode. [Figure 12] 5A and 5B are explanatory diagrams showing emission patterns of first illumination light and auxiliary measurement light. [Figure 13] FIG. 1 is a block diagram showing an illumination optical system having a focus lens. [Figure 14] 1A is an explanatory diagram showing focus control and imaging control in a fixed focus mode, and FIG. 1B is an explanatory diagram showing focus control and imaging control in a variable focus mode. DETAILED DESCRIPTION OF THE INVENTION

[0015] 1, the endoscope system 10 includes a light source device 12, an endoscope 13, a processor device 14, a display 15, and a user interface 16. The endoscope 13 is optically or electrically connected to the light source device 12 and electrically connected to the processor device 14.

[0016] The light source device 12 generates illumination light and supplies the generated illumination light to the endoscope 13. The endoscope 13 includes an insertion section 13a, which is a tubular member extending in one direction and is inserted into a subject, a tip section 13b, which is the tip of the insertion section 13a and emits illumination light and captures an image of the object to be observed, an operation section 13c, which is provided at the base end of the insertion section 13a and is used to perform various operations, and an angle knob 13d, which is provided adjacent to the operation section 13c. By rotating the angle knob 13d, the tip section 13b can be directed in a desired direction.

[0017] A universal cord 18 is provided at a position different from the position where the insertion section 13a is provided on the endoscope 13. The universal cord 18 has connectors 18a that are detachably connected to the light source device 12 and the processor device 14 of the endoscope 13.

[0018] The processor device 14 performs various processes based on the image of the object of observation captured by the endoscope 13. The image after the various processes is displayed on the display 15. The user interface 16 inputs various information to the processor device 14 in response to operation input from the user. Note that the user interface 16 preferably includes a mouse, microphone, tablet, foot switch, touch pen, etc. in addition to the keyboard shown in the figure.

[0019] The endoscope system 10 has two illumination light emission modes: a mono-emission mode and a multi-emission mode. In the mono-emission mode, the first illumination light is continuously emitted, and a first illumination light image based on the first illumination light is displayed on the display 15. In the multi-emission mode, the first illumination light and the second illumination light, which have different emission spectra, are emitted according to a specific emission pattern, and a first illumination light image based on the first illumination light and a second illumination light image based on the second illumination light are displayed on the display 15 according to a specific display mode. The user can switch between the above two modes by operating a mode selector switch (not shown) included in the operation unit 13c.

[0020] As shown in Fig. 2, the light source device 12 includes a light source section 20 and a light source processor 21. The light source section 20 generates illumination light for illuminating a subject. The light source section 20 uses a white light source that emits white light, or a plurality of light sources including a white light source and a light source that emits light of another color (for example, a blue light source that emits blue light), as a light source of the illumination light. The light source processor 21 controls the light source section 20 based on instructions from the processor device 14.

[0021] Illumination light emitted from the light source unit 20 is incident on the light guide LG. The light guide LG is provided inside the universal cord 18. The light from the light guide LG is emitted from the distal end 13b of the endoscope. Specifically, the illumination light is irradiated onto the subject from an illumination lens 22a included in the illumination optical system 22 of the distal end 13b.

[0022] The distal end 13b of the endoscope is provided with an imaging optical system 23 for capturing an image of an object to be observed. The imaging optical system 23 has an objective lens 24, a zoom lens 25, and an imaging sensor 26. Light reflected from the object to be observed is incident on the imaging sensor 26 via the objective lens 24 and the zoom lens 25. As a result, a reflected image of the object to be observed is formed on the imaging sensor 26.

[0023] The zoom lens 25 has an optical zoom function that zooms in or out of a subject by moving between the telephoto end and the wide-angle end. The optical zoom function can be switched on and off by a zoom operation unit (not shown) provided on the operation unit 13c of the endoscope.

[0024] The imaging sensor 26 is a color imaging sensor that captures a reflected image of the subject and outputs an image signal. The imaging sensor 26 is preferably a CCD (Charge Coupled Device) imaging sensor, a CMOS (Complementary Metal-Oxide Semiconductor) imaging sensor, or the like. The imaging sensor 26 used in the present invention is a color imaging sensor for obtaining red, green, and blue images of three colors: R (red), G (green), and B (blue). The red image is an image output from red pixels in the imaging sensor 26 that are provided with red color filters. The green image is an image output from green pixels in the imaging sensor 26 that are provided with green color filters. The blue image is an image output from blue pixels in the imaging sensor 26 that are provided with blue color filters.

[0025] The image signal output from the imaging sensor 26 is transmitted to the scope processor 28. The scope processor 28 is provided with a CDS / AGC circuit that performs correlated double sampling (CDS) and automatic gain control (AGC) on the analog image signal, or an A / D (Analog / Digital) converter that converts the analog image signal into a digital image signal. The image signal output from the scope processor 28 is input to the processor device 14 via a communication I / F (Interface) 30 of the light source device 12.

[0026] The processor device 14 has programs related to various processes or controls stored in a program storage memory (not shown). A system control unit 32 configured by a system processor provided in the processor device 14 executes the programs stored in the program storage memory, thereby realizing the functions of a receiving unit 33 connected to a communication I / F (Interface) 30 of the light source device 12, a signal processing unit 34, and a display control unit 35.

[0027] The receiving unit 33 receives the image signal transmitted from the communication I / F 30 and transmits it to the signal processing unit 34. The signal processing unit 34 has a built-in memory for temporarily storing the image signal received from the receiving unit 33, and processes the image signal group, which is a collection of the image signals stored in the memory, to generate an image of the subject. The display control unit 35 displays the generated image of the subject on the display 15.

[0028] Specifically, in the mono light emission mode, the first illumination light image is displayed on the entire display 15. In the multi light emission mode, as shown in Fig. 3, the first illumination light image is displayed on the main screen 15a of the display 15, and the second illumination light image is displayed on the sub-screen 15b of the display 15. The display area of ​​the sub-screen 15b is smaller than that of the main screen 15a.

[0029] The image sensor 26 will be described in detail below. As shown in Fig. 4, the image sensor 26 comprises an image pickup surface 36, a drive circuit 37, and a signal processing circuit 38. On the image pickup surface 36, a plurality of pixel rows 41, each of which is made up of a plurality of pixels 40 arranged in a row direction X, are arranged in a column direction Y that is perpendicular to the row direction X. The drive circuit 37 drives each pixel row 41 independently based on a drive control signal from the scope processor 28, resets each pixel 40 included in the pixel row 41 (discharges the charge accumulated in the photoelectric conversion element), and reads out an image signal according to the charge accumulated in the photoelectric conversion element of each pixel 40.

[0030] In this embodiment, the image sensor 26 uses rolling shutter driving. Rolling shutter driving includes rolling reset driving and rolling readout driving. Rolling reset driving is a driving method in which each pixel 40 in a pixel row 41 is reset and exposure of each pixel 40 is started, with the process being performed sequentially while changing the pixel row 41. Rolling readout driving is a driving method in which signals are read from each pixel 40 in an exposed pixel row 41 and exposure of the pixel row 41 is ended, with the process being performed sequentially while changing the pixel row 41. Note that the image sensor 26 may also use global shutter driving.

[0031] Light emission control and imaging control in the mono light emission mode and the multi light emission mode will now be described. The mono light emission mode and the multi light emission mode can be switched by a mode switching operation using the user interface 16. As shown in FIG. 5A, in the mono light emission mode, the first illumination light L1 is continuously emitted, and the rolling readout drive RD is performed according to the emission of each first illumination light L1. In the mono light emission mode, the light emission period Px of the first illumination light L1 and the signal readout period Rx by the rolling readout drive RD have the same length, and the light emission period Px and the signal readout period Rx overlap. Furthermore, the frame period FLx (Px+Rx) in the mono light emission mode is preferably, for example, 1 / 60 seconds.

[0032] On the other hand, in the multi-emission mode, first illumination light L1 and second illumination light L2, which have different emission spectra, are emitted in a switching manner according to a specific emission pattern. In Fig. 5(B), the specific emission pattern is to emit the first illumination light L1 for two frames, followed by the second illumination light L2 for one frame. In the multi-emission mode, to avoid color mixing caused by switching between the first illumination light and the second illumination light, which have different emission spectra, the emission period and the signal readout period of each illumination light are set so as not to overlap.

[0033] Therefore, while the first illumination light is emitted in the light emission period Py1, the rolling readout driving RD is not performed. After the light emission period Py1 of the first illumination light is completed, the rolling readout driving based on the emission of the first illumination light L1 is performed for the signal readout period Ry1. Similarly, while the second illumination light is emitted in the light emission period Py2, the rolling readout driving RD is not performed. After the light emission period Py2 of the second illumination light is completed, the rolling readout driving based on the emission of the second illumination light is performed for the signal readout period Ry2.

[0034] In the multi-emission mode, the light-emitting period Py1 of the first illumination light L1 and the signal readout period Ry1 are the same length, and the light-emitting period Py2 of the second illumination light L1 and the signal readout period Ry2 are the same length. The frame period FLy (Py1+Ry1 or Py2+Ry2) in the multi-emission mode is preferably, for example, 1 / 45 seconds. Comparing the multi-emission mode and the mono-emission mode, the light-emitting periods Py1 and Py2 in the multi-emission mode are high-speed light-emitting periods (for example, 1 / 90 seconds) that are shorter than the light-emitting period Px in the mono-emission mode. The signal readout periods Ry1 and Ry2 in the multi-emission mode are high-speed readout periods that are shorter than the signal readout period Rx in the mono-emission mode. Meanwhile, the frame period FLy in the multi-emission mode is longer than the light-emitting period FLx in the mono-emission mode (for example, 1 / 45 seconds) because the light-emitting period and the signal readout period do not overlap.

[0035] As described above, when switching between the mono-emission mode and the multi-emission mode, changes are made to the light emission control, including a change in the light emission period, and changes are made to the imaging control, including a change in the signal readout period. The endoscope system 10 of the present invention is configured to solve problems that arise from changes in the light emission control and the imaging control that accompany switching of the light emission mode.

[0036] In this embodiment, in the endoscopic system 10, a synchronization signal generated by imaging by the endoscope 13 is transmitted to the light source device 12 and the processor device 14, and when the abnormality detection function is performed based on the synchronization signal, light emission control and imaging control are changed by switching the light emission mode, etc., without disabling the abnormality detection function. To achieve this, as shown in FIG. 6, the scope processor 28 of the endoscope 13 is provided with a scope control unit 28a and a scope logic circuit 28b. In addition, the processor device 14 is provided with a histogram generation unit 45. In addition, the light source processor 21 of the light source device 12 is provided with a synchronization signal generation unit 21a and a light source control unit 21b.

[0037] If the loss of the synchronization signal is detected by the abnormality detection function of each processing unit or control unit of the light source device 12 and the processor device 14, it can be detected that an abnormality has occurred upstream of each processing unit or control unit. The scope control unit 28a, the system control unit 32, or the light source control unit 21b is preferably configured with a CPU (Central Processing Unit). The scope logic circuit 28b or the synchronization signal generation unit 21a is preferably configured with an FPGA (Field Programmable Gate Array).

[0038] The control of the light source device 12 and the processor device 14 during execution of the mono-flash mode or the multi-flash mode will be described below. A frame signal generated by the imaging sensor 26 of the endoscope 13 is transmitted to the light source device 12 and the processor device 14 by the scope control unit 28a. In addition, the scope control unit 28a generates a synchronization signal used for various controls each time a frame signal is generated. The generated synchronization signal is also transmitted to the light source device 12 and the processor device 14.

[0039] In the processor device 14, the signal processing unit 34 receives the frame signal and performs various signal processing based on the received frame signal. The display control unit 35 displays on the display 15 based on the frame signal that has been subjected to various signal processing. The signal processing unit 34 also receives a synchronization signal and controls various processing parameters based on the received synchronization signal. For example, it controls the update timing of image processing parameters for matrix coefficients such as color tone or structure enhancement.

[0040] The histogram generation unit 45 also receives a frame signal and a synchronization signal. Based on the received frame signal, the histogram generation unit 45 generates histogram information that represents the frequency of pixel values ​​of the frame signal. The histogram information is used to control the light intensity of the light source device 12. The histogram generation unit 45 transmits the synchronization signal and the histogram information to the system control unit 32. Based on the histogram information, the system control unit 32 calculates a target light intensity as light intensity control information. The calculated target light intensity is transmitted to the light source control unit 21b in accordance with the transmission timing based on the synchronization signal.

[0041] In the light source device 12, the synchronization signal generation unit 21a generates a synchronization signal used for timing light emission control based on the synchronization signal from the endoscope 13. The light source control unit 21b controls the light emission of the light source unit 20 so as to achieve the target light amount transmitted from the processor device 14, in accordance with the light emission timing based on the synchronization signal generated by the synchronization signal generation unit 21a.

[0042] The control of the light source device 12 and the processor device 14 when switching between the mono light emission mode and the multi light emission mode will be described below. As shown in FIG. 7, during execution of the mono light emission mode, the frame signal FSgx output from the imaging sensor 26 is transmitted to the light source device 12 and the processor device 14 via the scope logic circuit 28b together with a synchronization signal. When a switching operation from the mono light emission mode to the multi light emission mode is performed via the user interface 16, the system control unit 32 issues a sensor switching request to the scope control unit 28a to change the imaging drive method of the imaging sensor 26. Note that in FIG. 7, it is preferable to control the light source device 12 and the processor device 14 in a similar manner when switching from the multi light emission mode to the mono light emission mode. Furthermore, changing the imaging drive method includes changing the frame period (frame rate, etc.) as well as the signal readout period.

[0043] In response to the sensor switching request, the scope control unit 28a performs a switching start setting on the scope logic circuit 28b to start changing the imaging drive method of the imaging sensor 26. In accordance with the switching start setting, the scope logic circuit 28b stops transmitting the frame signal FSgx to the light source device 12 and the processor device 14. The switching start setting causes the imaging sensor 26 to change from the mono light-emission mode imaging drive method to the multi light-emission mode imaging drive method. Specifically, the frame period FLx is changed to the frame period FLy, and the signal readout period for the rolling readout drive RD is changed from Rx to Ry1, Ry2. After a certain time has passed since the switching start setting, the scope control unit 28a performs a switching completion setting on the scope logic circuit 28b to complete the change in the imaging drive method of the imaging sensor 26.

[0044] The scope logic circuit 28b generates a dummy signal DSg in place of the frame signal FSgx after a certain time has elapsed since the switching start setting. The dummy signal is a signal different from the frame signal and is artificially generated by the scope logic circuit 28b. The dummy signal DSg is transmitted to the light source device 12 and the processor device 14 together with a synchronization signal. Furthermore, after a certain time has elapsed since the switching completion setting, the scope logic circuit 28b stops generating the dummy signal DSg in response to the frame signal FSgy being transmitted from the imaging sensor 26. After stopping the generation of the dummy signal Dsg, the scope logic circuit 28b transmits the frame signal FSgy to the light source device 12 and the processor device 14. Furthermore, teeth Instead of the scope logic circuit 28b, the signal may be generated and output by a processor logic circuit (not shown) provided in the processor device 14.

[0045] As described above, the dummy signal DSg is transmitted together with a synchronization signal to the light source device 12 and the processor device 14, just like the frame signals FSgx and FSgy. Therefore, even in a situation where a frame signal is not output when the imaging drive method of the imaging sensor 26 is changed, the dummy signal DSg is transmitted together with a synchronization signal to the light source device 12 and the processor device 14 instead of the frame signal, so there is no need to disable the abnormality detection functions of the light source device 12 and the processor device 14.

[0046] It is preferable to assign a dummy signal identifier DSgk to the dummy signal DSg, as shown in Fig. 8. In the light source device 12 and the processor device 14, by analyzing the header information of the signal from the endoscope 13, it becomes possible to distinguish the following three types of signals S1 to S3 from the signal from the endoscope 13. S1: Frame signal before switching of imaging drive method (without dummy signal identifier DSgk) S2: Dummy signal during switching of imaging drive method (dummy signal identifier DSgk) S3: Frame signal after switching of imaging drive method (without dummy signal identifier DSgk)

[0047] In the light source device 12 and the processor device 14, a dummy signal and It is preferable to stop updating the image displayed on the display 15 at the timing of identification. After stopping the image update, image processing parameters to be used after changing the imaging drive method are set. For example, when switching from mono flash mode to multi flash mode, the image processing parameters to be used in multi flash mode are set. It is preferable that the image processing parameters include matrix coefficients for color tone or structure emphasis, etc.

[0048] In addition, when the signal is identified as a dummy signal, the target light amount is not calculated based on the dummy signal. source Control algorithm for light source during dummy signal identification control It is preferable to temporarily switch to the algorithm. Specifically, if the histogram used to calculate the target light amount is a histogram generated based on a dummy signal, the system control unit 32 does not use that histogram to calculate the target light amount. In this case, the histogram generation unit 45 generates a histogram (light source control information used to calculate the target light amount) based on the frame signal immediately before identifying the dummy signal, and the system control unit 32 calculates the target light amount based on the generated histogram. This prevents the system control unit 32 from calculating the target light amount using a histogram generated based on a dummy signal.

[0049] Furthermore, when a frame signal is identified after a dummy signal has been identified, the system control unit 32 executes the light source control algorithm based on the frame signal obtained after the frame signal has been identified. This stops the execution of the light source control algorithm during the dummy signal identification. Specifically, the system control unit 32 calculates a target light intensity corresponding to the light emission mode after the change in the imaging drive method. The light source control unit 21b performs light source control corresponding to the light emission mode after the change in the imaging drive method based on the calculated target light intensity.

[0050] For example, when switching to the mono flash mode, the first illumination light is continuously emitted based on the target light intensity corresponding to the first illumination light. On the other hand, when switching to the multi flash mode, the first illumination light and the second illumination light are switched and emitted according to a specific light emission pattern based on the target light intensity corresponding to the first and second illumination lights. light Then, the display control unit 35 resumes updating the video on the display 15 based on frame signals obtained after the signal has been identified as a frame signal.

[0051] Regarding the dummy signal DSg, instead of the dummy signal identifier DSgk, the light source device 12 and the processor device 14 signal For example, it is preferable that the dummy signal DSg includes an artificially generated mosaic-like dummy identification image, as shown in FIG.

[0052] Next, a series of steps for changing the imaging drive method of the imaging sensor will be described with reference to the flowchart shown in Fig. 10. Unless a sensor switching request for changing the imaging drive method is made to the scope control unit 28a, the scope logic circuit 28b outputs a frame signal and a synchronization signal to the processor device 14. When a sensor switching request is made to the scope control unit 28a, the scope control unit 28a instructs the scope logic circuit 28b to change the imaging drive method of the imaging sensor 26 in accordance with the sensor switching request. Imaging A switching start setting is performed to set the start of the drive system change. By the switching start setting, the image sensor 26 changes from the imaging drive system of the mono light emission mode to the imaging drive system of the multi light emission mode.

[0053] Furthermore, the scope logic circuit 28b outputs a dummy signal and a synchronization signal to the processor device 14 after a certain time has passed since the switching start setting. Until the scope control unit 28a performs a switching completion setting to set the completion of the change in the imaging drive method, the scope logic circuit 28b continues to output the dummy signal and the synchronization signal to the processor device 14. Then, when the scope control unit 28a performs the switching completion setting, the scope logic circuit 28b stops outputting the dummy signal and outputs a frame signal and a synchronization signal after the change in the imaging drive method to the processor device 14.

[0054] In the above embodiment, the present invention (such as generating a dummy signal when changing the imaging drive method) is applied when switching between the mono-emission mode and the multi-emission mode, but the present invention can also be applied when changing the imaging drive method in other embodiments using an imaging sensor. For example, as shown in Figure 11, the light emission control and imaging control in the mono-emission mode shown in (A) and the multi-color intermittent light emission mode shown in (B) can be applied to the mono-emission mode and the multi-color intermittent light emission mode shown in (C). of The present invention can also be applied to cases where light emission control and image capture control are switched.

[0055] In the multi-color intermittent light emission mode, in addition to emitting the first illumination light, the third illumination light is intermittently emitted simultaneously with the first illumination light. P The third illumination light is repeatedly emitted during the light emission period Ry and not emitted during the signal readout period Ry. P The first illumination light is emitted during the signal readout period Ry, but the second illumination light is not emitted during the signal readout period Ry. conduct .

[0056] In the multi-color intermittent light emission mode, the light emission period Py and the signal readout period Ry are the same length. Furthermore, the frame period FLy (Py+Ry) in the multi-color intermittent light emission mode is preferably, for example, 1 / 45 seconds. Comparing the multi-color intermittent light emission mode with the mono light emission mode, the light emission period Py in the multi-color intermittent light emission mode is a high-speed light emission period (for example, 1 / 90 seconds) that is shorter than the light emission period Px in the mono light emission mode. Furthermore, the signal readout period Ry in the multi-color intermittent light emission mode is a high-speed readout period that is shorter than the signal readout period Rx in the mono light emission mode. Meanwhile, the frame period FLy in the multi-color intermittent light emission mode is longer than the light emission period FLx in the mono light emission mode (for example, 1 / 45 seconds) so that the light emission period and the signal readout period do not overlap.

[0057] The third illumination light is, for example, a measurement assist light ML for measuring the size of the object. As shown in Fig. 12, the measurement assist light ML is preferably emitted from an assist light emitting section 47 for measurement assist light, which is separate from the illumination optical system 22 at the tip 13b of the endoscope. The assist light emitting section 47 is arranged so that the optical axis L1 of the first illumination light and the optical axis of the measurement assist light ML intersect, so that the measurement assist light ML can be adjusted in accordance with the distance to the object of observation. ML moves up and down on the screen. The processor device 14 recognizes the vertical movement of the measurement assist light, thereby recognizing the distance to the object to be observed, and can display on the display 15 a size measurement scale corresponding to the observation distance.

[0058] 13, in the case where the imaging optical system 23 is provided with a focus lens 50, it is preferable to provide a focus variable mode in which the position of the focus lens 50 is periodically varied between focus positions PA and PB, in addition to a focus fixed mode in which the position of the focus lens 50 is fixed. The present invention can be applied when switching between the focus fixed mode and the focus variable mode, as shown in FIG. 14. Switching between the focus fixed mode and the focus variable mode is performed by the user interface 16.

[0059] As shown in FIG. 14A, in the fixed focus mode, the position of the focus lens 50 is fixed at a specific position between focus positions PA and PB. In the fixed focus mode, the rolling readout drive RD is performed during a signal readout period Rp. The signal readout period Rp is preferably, for example, 1 / 60 seconds. On the other hand, as shown in FIG. 14B, in the variable focus mode, the position of the focus lens 50 periodically fluctuates between focus positions PA and PB. In the variable focus mode, the rolling readout drive RD is performed during a signal readout period Rq that is shorter than the signal readout period Rp. By making the signal readout period Rq shorter than the signal readout period Rp, problems (such as blurring) associated with fluctuations in the position of the focus lens 50 can be resolved. The signal readout period Rq is preferably, for example, 1 / 45 seconds. Note that the frame period FLp (same as the signal readout period Rp) represents the frame period in the fixed focus mode, and the frame period FLq (same as the signal readout period Rq) represents the frame period in the variable focus mode.

[0060] 14 assumes that the fixed focus mode and the variable focus mode are executed in the mono light emission mode, but the fixed focus mode and the variable focus mode may also be executed in the multi light emission mode. The present invention may also be applied when switching between the fixed focus mode and the variable focus mode in various imaging devices (e.g., digital cameras) other than the endoscope system 10.

[0061] In the above embodiment, the hardware structure of the processing unit that executes various processes is the following various processors: The various processors include a CPU (Central Processing Unit), which is a general-purpose processor that executes software (programs) and functions as various processing units, a GPU (Graphical Processing Unit), a programmable logic device (PLD), which is a processor whose circuit configuration can be changed after manufacturing such as an FPGA (Field Programmable Gate Array), and a dedicated electric circuit, which is a processor having a circuit configuration designed specifically for executing various processes.

[0062] A single processing unit may be configured with one of these various processors, or may be configured with a combination of two or more processors of the same or different types (e.g., multiple FPGAs, a combination of a CPU and an FPGA, or a combination of a CPU and a GPU). Also, multiple processing units may be configured with a single processor. Examples of multiple processing units configured with a single processor include, first, a configuration in which one processor is configured with a combination of one or more CPUs and software, as typified by client or server computers, and this processor functions as multiple processing units. Second, a configuration in which a processor is used to realize the functions of an entire system including multiple processing units on a single IC (Integrated Circuit) chip, as typified by a system-on-chip (SoC). In this way, the various processing units are configured with one or more of the above-mentioned various processors as a hardware structure.

[0063] Furthermore, the hardware structure of these various processors is, more specifically, an electric circuit formed by combining circuit elements such as semiconductor elements, and the hardware structure of the memory unit is a storage device such as a hard disk drive (HDD) or a solid state drive (SSD). [Explanation of symbols]

[0064] 10 Endoscopy System 12 Light source device 13 Endoscopy 13a Insertion part 13b Tip 13c Control unit 13d angle knob 14 Processor unit 15 Display 15a Main screen 15b Subscreen 16 User Interface 18 Universal Code 18a connector 20 Light source section 21 Light Source Processor 21a Synchronization signal generation section 21b Light source control unit 22 Illumination optical system 22a Lighting lens 23 Imaging optical system 24 objective lenses 25 Zoom Lens 26 Image sensor 28 Scope Processor 28a Scope control section 28b Scope Logic Circuit 30 Communication I / F 32 System control section 33 Receiving unit 34 Signal processing section 35 Display control unit 36 imaging surface 37 Drive circuit 38 Signal Processing Circuit 40 pixels 41 pixel rows 45 Histogram generation unit 47 Auxiliary light output section 50 focus lens DSg Dummy signal DSgk Dummy signal identifier F L x, F L y frame duration L1 1st illumination light L2 2nd illumination light LG Light Guide Px, Py1, Py2, Py light emission period Rx, Ry, Ry1, Ry2 signal read period RD Rolling read drive X row direction Y column direction

Claims

1. An endoscope having an image sensor and a scope processor, and a processor device having a system processor, The system processor a sensor switching request for changing the imaging drive method of the imaging sensor is sent to the scope processor when the imaging drive method is to be changed; When the imaging drive method is not to be changed, either the scope processor or the system processor images an object to be observed and outputs a frame signal and a synchronization signal output from the imaging sensor to the processor device, and when the imaging drive method is to be changed in accordance with the sensor switching request, outputs a dummy signal and a synchronization signal that are artificially generated and are different from the frame signal to the processor device; The system processor performs an abnormality detection function based on the synchronization signal. Endoscopy system.

2. The endoscope system according to claim 1 , wherein a dummy signal identifier is assigned to the dummy signal.

3. Either the scope processor or the system processor If the dummy signal identifier is not present, the frame signal is identified as being a signal before the switching of the imaging drive method or a signal after the switching of the imaging drive method; The endoscope system according to claim 2, wherein, if the dummy signal identifier is present, the signal is identified as the dummy signal during switching of the imaging drive method.

4. The system processor 4. The endoscope system according to claim 3, wherein updating of the image displayed on the display is stopped at the timing when the signal is identified as the dummy signal.

5. The system processor 5. The endoscope system according to claim 3, wherein an image processing parameter to be used after the imaging drive method is changed is set at the timing when the signal is identified as the dummy signal.

6. The system processor 6. The endoscope system according to claim 3, wherein, at the timing when the signal is identified as a dummy signal, the light source control algorithm is temporarily switched to the light source control algorithm that is currently identifying the dummy signal.

7. The endoscope system according to claim 6, wherein the algorithm used during the dummy signal identification includes generating light source control information used to calculate a target light intensity based on a frame signal immediately before the frame signal used to identify the dummy signal.

8. The system processor An endoscope system as described in any one of claims 3 to 7, wherein a light source control algorithm is executed based on the frame signal obtained after identifying the frame signal at the timing when the frame signal is identified after identifying the dummy signal.

9. The system processor An endoscope system as described in any one of claims 1 to 8, wherein, at the timing when the frame signal is identified after the dummy signal is identified, image updating on the display is resumed based on the frame signal obtained after the frame signal is identified.

10. The endoscope system according to claim 1 , wherein the dummy signal includes a dummy identification image.

11. A method for operating an endoscope system including an endoscope having an imaging sensor and a scope processor, and a processor device having a system processor, comprising: a step in which the system processor issues a sensor switching request to the scope processor to change the imaging drive method of the imaging sensor when the imaging drive method is to be changed; a step of outputting a frame signal and a synchronization signal output from the imaging sensor after imaging an object to the processor device when the scope processor or the system processor does not change the imaging drive method, and outputting a dummy signal and a synchronization signal, which are different from the frame signal and are artificially generated, to the processor device when the imaging drive method is to be changed in accordance with the sensor switching request, A method for operating an endoscope system, wherein the system processor performs an abnormality detection function based on the synchronization signal.

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