Light source apparatus and subject observation system

Abstract

The invention provides a light source apparatus and a subject observation system. The light source device 6 includes: a first light source 461 for emitting laser light; a second light source 462 for emitting light; and a light source control unit (472) for controlling the operation of the first light source (461) and the second light source (462). A light source control unit (472) performs switching control of switching an illumination state from a first light source (461) to a second light source (462) on a laser beam emitted from the first light source (461) and irradiated on a subject on the basis of a time reference corresponding to a category specified by a laser standard indicating a laser product safety standard.

Description

[0001] This application is a divisional application of the Chinese national phase application of an international application with an international filing date of October 27, 2020, an international application number of PCT / JP2020 / 040303, and an invention title of "Light Source Device and Specimen Observation System". The entry date of this Chinese national phase application into the national phase is May 6, 2022, the application number is 202080077307.5, and the invention title is "Light Source Device and Specimen Observation System". Technical Field

[0002] The present disclosure relates to a light source device and a specimen observation system. Background Art

[0003] There is known a laser product that observes a specimen by applying a laser to the specimen (for example, see Patent Document 1).

[0004] In the laser product described in Patent Document 1, in order to meet the requirements specified by a laser standard indicating the safety standard of the laser product and ensure safety, the amount of laser emitted within a specific period is limited to a value below a reference value.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Patent No. 6392887 Summary of the Invention

[0008] Technical Problem

[0009] Incidentally, a laser product that observes a specimen by irradiating the specimen with a laser requires as high a light amount as possible. However, when protective glasses for protecting the eyes from the influence of the laser need to be worn, the protective glasses make the color look different from the actual color, thereby reducing the observation performance. That is, as high a light amount as possible is required within the range where safety is ensured without wearing the protective glasses.

[0010] Here, assume a laser product that can switch between a laser and, for example, a light-emitting diode (LED). If the laser and the LED light are mixed within a time base according to the category specified by the laser standard of the laser, the exposure emission amount (AE) at the time of switching between the laser and the LED light is greater than the exposure emission amount in the illumination state of the laser alone, which may cause the laser product to reach a category where protective glasses need to be worn.

[0011] Therefore, in a laser product, a technique capable of ensuring the light amount of the emitted light while ensuring safety is required.

[0012] The present disclosure has been made in view of the above circumstances, and an object of the present disclosure is to provide a light source device and a subject observation system that can ensure the amount of light emitted while ensuring safety.

[0013] Solution to the problem

[0014] In order to solve the above problems and achieve the object, a light source device according to the present disclosure includes: a first light source configured to emit laser light; a second light source configured to emit light; and a light source control unit configured to control the operations of the first light source and the second light source; wherein the light source control unit is configured to perform each of a first switching control and a second switching control on the laser light emitted from the first light source and irradiated on a subject based on a time reference according to a category specified by a laser standard indicating the safety standard of a laser product, the first switching control refers to switching the illumination state from the first light source to the second light source, and the second switching control refers to switching the illumination state from the second light source to the first light source.

[0015] Moreover, in the above-described light source device according to the present disclosure, in the first switching control, after a time equal to or greater than the time reference has elapsed since the first light source was turned off, the second light source is turned on; and in the second switching control, after a time equal to or greater than the time reference has elapsed since the second light source was turned off, the first light source is turned on.

[0016] Moreover, the above-described light source device according to the present disclosure further includes: a light amount detection unit configured to detect the light amount of the laser light emitted from the first light source and the light amount of the light emitted from the second light source; and in the first switching control, within the period from when the first light source was turned off until the time reference has elapsed, the light amount of the second light source is adjusted based on the total amount of light detected by the light amount detection unit from a time point earlier than the current time by the time reference to the current time and an exposure emission limit set according to the category; and in the second switching control, within the period from when the second light source was turned off until the time reference has elapsed, the light amount of the first light source is adjusted based on the total amount of light detected by the light amount detection unit from a time point earlier than the current time by the time reference to the current time and the exposure emission limit.

[0017] A light source device according to the present disclosure includes: a first light source configured to emit laser light; a second light source configured to emit light; and a light source control unit configured to control the operations of the first light source and the second light source; wherein the light source control unit is configured to perform a switching control for switching the illumination state from the first light source to the second light source on the laser light emitted from the first light source and irradiated on a subject based on a time reference according to a category specified by a laser standard indicating the safety standard of a laser product.

[0018] In the above-described light source device according to the present disclosure, in the switching control, after a time equal to or greater than the time reference has elapsed since the first light source is turned off, the second light source is turned on.

[0019] The above-described light source device according to the present disclosure further includes: a light quantity detection unit configured to detect the light quantity of the laser emitted from the first light source and the light quantity of the light emitted from the second light source; and in the switching control, within the period after the first light source is turned off and after a time reference has elapsed, the light quantity of the second light source is adjusted based on the total amount of light detected by the light quantity detection unit from a time point earlier than the current time by the time reference to the current time and the exposure emission limit set according to the category.

[0020] The light source device according to the present disclosure includes: a first light source configured to emit a laser; a second light source configured to emit light; and a light source control unit configured to control the operations of the first light source and the second light source; wherein the light source control unit is configured to perform switching control for switching the illumination state from the second light source to the first light source on the laser emitted from the first light source and irradiated on the subject based on a time reference according to the category specified by a laser standard indicating the safety standard of the laser product.

[0021] In the above-described light source device according to the present disclosure, in the switching control, after a time equal to or greater than the time reference has elapsed since the second light source is turned off, the first light source is turned on.

[0022] The above-described light source device according to the present disclosure further includes: a light quantity detection unit configured to detect the light quantity of the laser emitted from the first light source and the light quantity of the light emitted from the second light source; and in the switching control, within the period after the second light source is turned off and after a time reference has elapsed, the light quantity of the first light source is adjusted based on the total amount of light detected by the light quantity detection unit from a time point earlier than the current time by the time reference to the current time and the exposure emission limit set according to the category.

[0023] In the above-described light source device according to the present disclosure, the category refers to Category 2 or Category 2M specified by the laser standard or Category 3R in the wavelength range of 400 nm to 700 nm.

[0024] In the above-described light source device according to the present disclosure, the light source control unit is configured to emit the laser from the first light source in the form of pulses.

[0025] The subject observation system according to the present disclosure includes: the above-described light source device; and an imaging device configured to capture an image of the subject irradiated with the light from the light source device.

[0026] A light source device according to the present disclosure includes: a first light source configured to emit laser light; a second light source configured to emit light; and a light source control unit configured to control operations of the first light source and the second light source; wherein the light source control unit is configured to perform switching control for switching an illumination state from the first light source to the second light source on the laser light that is emitted from the first light source and irradiated on a subject based on a time reference according to a category specified by a laser standard indicating a safety standard for laser products.

[0027] A light source device according to the present disclosure includes: a first light source configured to emit laser light; a second light source configured to emit light; and a light source control unit configured to control operations of the first light source and the second light source; wherein the light source control unit is configured to perform switching control for switching an illumination state from the second light source to the first light source on the laser light that is emitted from the first light source and irradiated on a subject based on a time reference according to a category specified by a laser standard indicating a safety standard for laser products.

[0028] A subject observation system according to the present disclosure includes: a light source device including: a first light source configured to emit laser light; a second light source configured to emit light; and a light source control unit configured to control operations of the first light source and the second light source; wherein the light source control unit is configured to perform switching control for switching an illumination state from the first light source to the second light source on the laser light that is emitted from the first light source and irradiated on a subject based on a time reference according to a category specified by a laser standard indicating a safety standard for laser products; and an imaging device configured to capture an image of the subject irradiated with light from the light source device.

[0029] A subject observation system according to the present disclosure includes: a light source device including: a first light source configured to emit laser light; a second light source configured to emit light; and a light source control unit configured to control operations of the first light source and the second light source; wherein the light source control unit is configured to perform switching control for switching an illumination state from the second light source to the first light source on the laser light that is emitted from the first light source and irradiated on a subject based on a time reference according to a category specified by a laser standard indicating a safety standard for laser products; and an imaging device configured to capture an image of the subject irradiated with light from the light source device.

[0030] Advantageous effects of the invention

[0031] The light source device and the subject observation system according to the present disclosure can ensure the amount of emitted light while ensuring safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a block diagram showing a subject observation system according to the first embodiment.

[0033] Figure 2 is a flowchart showing a light source control method executed by a control device.

[0034] Figure 3 Shows a second switching control.

[0035] Figure 4 Shows a first switching control.

[0036] Figure 5 is a block diagram showing a subject observation system according to a second embodiment.

[0037] Figure 6 is a flowchart showing a light source control method executed by a control device.

[0038] Figure 7 is a flowchart showing a second switching control.

[0039] Figure 8 Shows a second switching control.

[0040] Figure 9 is a flowchart showing a first switching control.

[0041] Figure 10 Shows a first switching control. Detailed Embodiments

[0042] Embodiments for implementing the present disclosure (hereinafter referred to as embodiments) will be described below with reference to the drawings. It should be noted that the present disclosure is not limited by the embodiments described below. Also, in the drawings, the same components are given the same reference numerals.

[0043] (First Embodiment)

[0044] [Schematic Configuration of Subject Observation System]

[0045] Figure 1 is a block diagram showing a subject observation system 1 according to the first embodiment.

[0046] The subject observation system 1 refers to a strobe endoscope system for observing the vocal cords of a subject (object to be imaged) in the medical field. As Figure 1 shown, the subject observation system 1 includes an endoscope 2, a voice input device 3, a control device 4, and a display device 5.

[0047] The endoscope 2 captures a subject image from the subject. As Figure 1 shown, the endoscope 2 includes an insertion portion 21, an operation unit 22, and a general-purpose cord 23.

[0048] The insertion portion 21 has an elongated shape. As Figure 1 shown, the light guide 24, i.e., the illumination optical fiber, is inserted through the insertion portion 21. Further, an illumination lens 25 is provided at the distal end portion of the insertion portion 21 so as to face the exit end of the light guide 24. Accordingly, the light emitted from the light guide 24 is emitted from the distal end of the insertion portion 21 via the illumination lens 25.

[0049] Further, as Figure 1 shown, the imaging unit 26 is provided at the distal end portion of the insertion portion 21.

[0050] The imaging unit 26 captures the light (subject image) that is irradiated onto the subject via the illumination lens 25 and reflected by the subject into the insertion portion 21 and captures the subject image. As Figure 1 shown, the imaging unit 26 includes an optical system 261 and an imaging element 262.

[0051] The optical system 261 includes one or more lenses. The optical system 261 captures the subject image from the subject into the insertion portion 21 and forms an image on the light receiving surface of the imaging element 262 (light receiving unit 263).

[0052] Under the control of the control device 4, the imaging element 262 sequentially captures the subject images formed by the optical system 261 at a specific frame rate. As Figure 1 shown, the imaging element 262 includes a light receiving unit 263 and a reading unit 264.

[0053] A plurality of pixels are arranged on the light receiving surface of the light receiving unit 263. The plurality of pixels receive the subject image formed by the optical system 261 and generate pixel signals by performing photoelectric conversion on the received subject image. The plurality of pixels are arranged in a matrix such that a plurality of pixel rows (horizontal lines) are arranged in the vertical direction. The plurality of pixel rows (horizontal lines) include two or more pixels arranged along the horizontal direction. Accordingly, the light receiving unit 263 generates pixel signals representing the subject from the subject image formed on the light receiving surface.

[0054] The reading unit 264 exposes the plurality of pixels in the light receiving unit 263 and reads the pixel signals from the plurality of pixels.

[0055] The above-described imaging element 262 may include a complementary metal oxide semiconductor (CMOS) imaging element or a charge coupled device (CCD) imaging element. The CMOS imaging element generates pixel signals by the rolling shutter method. The CCD imaging element generates pixel signals by the global shutter method.

[0056] Further, as Figure 1As shown in the figure, the cable 27 is inserted into the insertion portion 21. For example, the cable 27 transmits pixel signals and control signals. That is, the imaging unit 26 generates pixel signals by the rolling shutter method or the global shutter method according to the control signals transmitted from the control device 4 via the cable 27 and outputs the pixel signals to the control device 4 via the cable 27.

[0057] The operation unit 22 is connected to one side of the proximal end of the insertion portion 21 and is provided with various switches (not shown) for receiving user operations of a user such as a doctor. In the first embodiment, the operation unit 22 is provided with switches for receiving a first user operation and a second user operation. The subject observation system 1 is set to the stroboscopic observation mode by the first user operation. The subject observation system 1 is set to the normal observation mode by the second user operation. Here, in the stroboscopic observation mode, pulsed light, that is, laser light, is irradiated onto the vocal cords to observe the vocal cords. In contrast, in the normal observation mode, white light, that is, LED light, is irradiated onto the subject to observe the subject. Then, the operation unit 22 outputs an operation signal to the control device 4 via the cable 27 in response to the user operation.

[0058] The general-purpose cord 23 extends from the operation unit 22 and is provided with an optical guide 24, a cable 27, etc. Then, the proximal end of the general-purpose cord 23 is connected to the control device 4 through the connector 23a.

[0059] As Figure 1 shown in the figure, the voice input device 3 is connected to the voice input terminal 4a of the control device 4 via the cord 31. The voice input device 3 inputs voice and outputs a voice signal. Then, the voice signal is output to the control device 4 via the cord 31.

[0060] It should be noted that the voice input device 3 may be configured to operate under the control of the control device 4 only when the subject observation system 1 is in the stroboscopic observation mode. Alternatively, the voice input device 3 may be configured to operate even when the subject observation system 1 is in any of the stroboscopic observation mode and the normal observation mode.

[0061] The control device 4 includes a CPU (Central Processing Unit), an FPGA (Field Programmable Gate Array), etc., and completely controls the operations of the imaging unit 26 and the display device 5. It should be noted that the detailed configuration of the control device 4 will be described in the "Configuration of the Control Device" described later.

[0062] The display device 5 includes a display formed of liquid crystal organic EL (Electro-Luminescence), etc. The display device 5 displays an image based on the display image signal from the control device 4 under the control of the control device 4.

[0063] [Configuration of the Control Device]

[0064] Next, the configuration of the control device 4 will be described.

[0065] As Figure 1 shown in, the control device 4 includes an input unit 41, a vibration frequency detection unit 42, a memory 43, an image processing unit 44, a display control unit 45, a light source device main body 46, and a control unit 47.

[0066] The input unit 41 includes operation devices such as a mouse, a keyboard, and a touch panel, and receives user operations from a user such as a doctor. Then, the input unit 41 outputs an operation signal to the control unit 47 in response to the user operation.

[0067] The vibration frequency detection unit 42 detects the frequency of the voice (vibration frequency of the vocal cords) input to the voice input device 3 based on the voice signal output from the voice input device 3. Then, the vibration frequency detection unit 42 outputs the detected voice frequency to the control unit 47.

[0068] It should be noted that the vibration frequency detection unit 42 may be configured to operate under the control of the control unit 47 only when the subject observation system 1 is in the stroboscopic observation mode. Alternatively, the vibration frequency detection unit 42 may be configured to operate even when the subject observation system 1 is in any of the stroboscopic observation mode and the normal observation mode.

[0069] For example, the memory 43 includes a DRAM (Dynamic Random Access Memory). The memory 43 temporarily stores a plurality of frames of pixel signals sequentially read from the reading unit 264. Further, the memory 43 temporarily stores a plurality of frames of pseudo-pixel signals, which will be described below, generated by the image processing unit 44.

[0070] When the subject observation system 1 is in the stroboscopic observation mode, the image processing unit 44 performs the following processing under the control of the control unit 47.

[0071] That is, the image processing unit 44 generates pseudo-pixel signals from the pixel signals of a plurality of consecutive frames stored in the memory 43. The pseudo-pixel signals correspond to the pixel signals in this case, that is, in which all the pixels of the exposure light receiving unit 263 are during the irradiation period of the pulsed light (laser) performed by the light source device main body 46. It should be noted that a known generation method (for example, see Japanese Patent No. 5948512) can be adopted as the method for generating pseudo-pixel signals (pixel signals during irradiation).

[0072] Further, even when the subject observation system 1 is in any of the stroboscopic observation mode and the normal observation mode, the image processing unit 44 also performs the following processing under the control of the control unit 47.

[0073] That is, the image processing unit 44 performs predetermined image processing on the pixel signals of a plurality of pixels read by the reading unit 264. For example, the image processing unit 44 performs image processing on the pixel signals. The image processing includes optical black subtraction processing, white balance (WB) adjustment processing, demosaicing processing (when the imaging element 262 includes a Bayer array color filter (not shown)), color matrix calculation processing, gamma correction processing, color reproduction processing, edge enhancement processing, and the like.

[0074] As shown below, when the subject observation system 1 is in the stroboscopic observation mode, the display control unit 45 generates a display image signal under the control of the control unit 47.

[0075] That is, the display control unit 45 generates a display image signal displayed on the display device 5 from each pseudo-pixel signal by pulsed light (laser) included in the display cycle of the display device 5. It should be noted that a known generation method (for example, see Japanese Patent No. 5948512) can be adopted as the method for generating the display image signal.

[0076] Furthermore, when the subject observation system 1 is in the normal observation mode, the display control unit 45 generates a display image signal displayed on the display device 5 from the pixel signals under the control of the control unit 47, and the image processing unit 44 performs image processing on the pixel signals.

[0077] As Figure 1 shown, the light source device main body 46 includes a first light source 461 and a second light source 462, a first light guide path 463 and a second light guide path 464, a first light source driver 465 and a second light source driver 466, and a first light quantity detection unit 467. It should be noted that in the first embodiment, although the light source device main body 46 is built in the control device 4, however, it is not limited thereto. The light source device main body 46 can be independent of the control device 4.

[0078] The first light source 461 includes a semiconductor laser and emits pulsed light (laser) in response to the supplied drive current (pulsed current).

[0079] In the first embodiment, a semiconductor laser is used in the first light source 461. In the semiconductor laser, the subject observation system 1 is a laser product of Class 2, Class 2M, or Class 3R. Class 2 and Class 2M are defined by a laser standard (e.g., IEC 60825-1:2014) indicating "Safety standards for laser products". Class 3R has a wavelength range of 400 nm to 700 nm. Here, the class of the laser product is determined based on the laser emitted from the first light source 461 and then emitted from the distal end of the insertion portion 21. It should be noted that for laser products of Class 2, Class 2M, and Class 3R with a wavelength range of 400 nm to 700 nm, it is not necessary to wear protective glasses.

[0080] The second light source 462 includes an LED that emits white light and emits white light (LED light) in response to the supplied drive current.

[0081] For example, the first light guide path 463 includes an optical fiber or the like and guides the pulsed light (laser) emitted from the first light source 461 to the incident end of the light guide 24. Then, the pulsed light (laser) is emitted from the distal end of the insertion portion 21 via the light guide 24 and the illumination lens 25.

[0082] For example, the second light guide path 464 includes an optical fiber or the like and guides the white light (LED light) emitted from the second light source 462 to the incident end of the light guide 24. Then, the white light (LED light) is emitted from the distal end of the insertion portion 21 via the light guide 24 and the illumination lens 25.

[0083] The first light source driver 465 supplies a drive current (pulsed current) to the first light source 461 under the control of the control unit 47. It should be noted that the first light source driver 465 operates under the control of the control unit 47 only when the subject observation system 1 is in the stroboscopic observation mode. That is, the first light source 461 emits pulsed light (laser) only when the subject observation system 1 is in the stroboscopic observation mode.

[0084] The second light source driver 466 supplies a drive current to the second light source 462 under the control of the control unit 47. It should be noted that the second light source driver 466 operates under the control of the control unit 47 only when the subject observation system 1 is in the normal observation mode. That is, the second light source 462 emits white light (LED light) only when the subject observation system 1 is in the normal observation mode.

[0085] The first light quantity detection unit 467 corresponds to the light quantity detection unit according to the present disclosure. For example, the first light quantity detection unit 467 includes a photodiode or the like and is installed in the first light guide path 463. Then, the first light quantity detection unit 467 receives a part of the pulsed light (laser light) emitted from the first light source 461 and following the first light guide path 463, and detects the light quantity of the pulsed light (laser light) under the control of the control unit 47.

[0086] For example, the control unit 47 includes a CPU, an FPGA, etc. The control unit 47 controls the operations of the imaging unit 26 and the display device 5 while controlling the operation of the entire control device 4. Further, the control unit 47 sets the subject observation system 1 to one of a stroboscopic observation mode and a normal observation mode in response to a first user operation and a second user operation performed by a user such as a doctor on the operation unit 22. As Figure 1 shown, the control unit 47 includes an imaging control unit 471 and a light source control unit 472.

[0087] The imaging control unit 471 performs exposure control on the imaging element 262 at a specific frame rate by a rolling shutter method or a global shutter method.

[0088] When the subject observation system 1 is in the normal observation mode, the light source control unit 472 controls the operation of the second light source driver 466 and causes the second light source 462 to emit white light (LED light). On the contrary, when the subject observation system 1 is in the stroboscopic observation mode, the light source control unit 472 controls the operation of the first light source driver 465 and causes the first light source 461 to emit pulsed light (laser light) in synchronization with the frequency of the voice emitted from the vocal cords detected by the vibration frequency detection unit 42.

[0089] The above-described light source device main body 46 and the light source control unit 472 correspond to the light source device 6 according to the present disclosure ( Figure 1 ).

[0090] [Operation of the control device]

[0091] Next, the operation of the above-described control device 4 will be described with reference to Figure 2 . It should be noted that for the sake of clarity, the light source control method for controlling the operations of the first light source 461 and the second light source 462 will be mainly described below.

[0092] Figure 2 is a flowchart showing the light source control method executed by the control device 4.

[0093] First, after activating the subject observation system 1, the control unit 47 sets the subject observation system 1 to the normal observation mode (step S1). Then, simultaneously, while setting the subject observation system 1 to the normal observation mode, the light source control unit 472 controls the operation of the second light source driver 466 and causes the second light source 462 to emit white light (LED light) (step S2).

[0094] In the normal observation mode, while checking the captured image obtained by capturing the subject image of the subject irradiated with white light on the screen of the display device 5, a user such as a doctor brings the distal end of the insertion section 21 close to the vocal cords. Then, after bringing the distal end of the insertion section 21 close to the vocal cords, the user such as a doctor performs a first user operation on the operation unit 22.

[0095] In step S2, the control unit 47 continuously monitors whether the first user operation has been performed (step S3).

[0096] When it is determined that the first user operation has been performed (step S3: YES), the control unit 47 sets the subject observation system 1 to the stroboscopic observation mode (step S5). Then, while setting the subject observation system 1 to the stroboscopic observation mode, the light source control unit 472 controls the operation of the first light source driver 465 and causes the first light source 461 to emit pulsed light (laser) in synchronization with the frequency of the voice emitted from the vocal cords detected by the vibration frequency detection unit 42 (step S6).

[0097] Here, when the control unit 47 switches the subject observation system 1 from the normal observation mode to the stroboscopic observation mode, the light source control unit 472 performs a second switching mode of switching the illumination state from the second light source 462 to the first light source 461 (step S4).

[0098] Figure 3 The second switching control is shown. Specifically, in Figure 3 , the vertical axis represents the light amount of the light emitted from the first light source 461 and the second light source 462, and the horizontal axis represents time.

[0099] As Figure 3 shown in, in the second switching control according to the first embodiment, after a time reference has elapsed since the second light source 462 was turned off, the first light source 461 is turned on. The time reference is specified by the laser standard (for example, IEC60825-1: 2014) of the "Safety Standard for Laser Products" indicating Class 2 or Class 2M or the wavelength range of 400 nm to 700 nm of Class 3R of the subject observation system 1 (laser product). The time reference is 0.25 [s].[[]]END]]

[0100] Further, while the light source control unit 472 emits pulsed light (laser light) from the first light source 461, it controls the operation of the first light quantity detection unit 467 (step S6) to start detecting the light quantity of the pulsed light (laser light) (step S7).

[0101] After step S7, the light source control unit 472 converts the total amount of light detected by the first light quantity detection unit 467 from a time point that is the above-mentioned time reference (0.25 [s]) earlier than the current time to the current time into the light quantity of light emitted from the distal end of the insertion portion 21 (hereinafter referred to as the distal end emission light quantity). Further, the light source control unit 472 calculates the exposure emission amount (AE) specified by a laser standard (e.g., IEC60825-1:2014) indicating the "safety standard for laser products" by using the distal end emission light quantity, beam divergence (design value), etc. based on the measurement conditions (e.g., measurement distance) described in the following standard (step S8).

[0102] After step S8, the light source control unit 472 compares the exposure emission amount (AE) calculated in step S8 with a specific threshold value (step S9). The light source control unit 472 adjusts the light quantity of the pulsed light (laser light) emitted from the first light source 461 at the current time so that the exposure emission amount does not exceed the specific threshold value (step S10).

[0103] Here, the specific threshold value refers to the lowest value obtained by calculating "AEL single ", "AEL s.p.train ", and "AEL s.p.T ", that is, the exposure emission limit (AEL) specified by a laser standard (e.g., IEC60825-1:2014) indicating the "safety standard for laser products".

[0104] It should be noted that "AEL single ", "AEL s.p.train ", and "AEL s.p.T " can be calculated by using the wavelength of the pulsed light (laser light), emission duration, light source size, frequency of the pulsed light (laser light), time reference, etc.

[0105] After step S10, the control unit 47 continuously monitors whether the second user operation has been performed (step S11).

[0106] If it is determined that the second user operation has not been performed (step S11: no), the control unit 47 returns to step S8.

[0107] On the contrary, if it is determined that the second user operation has been performed (step S11: yes), the control unit 47 returns to step S1. That is, steps S8 to S10 are repeatedly executed at a specific time interval.

[0108] Here, when the control unit 47 switches the subject observation system 1 from the stroboscopic observation mode to the normal observation mode, the light source control unit 472 performs first switching control to switch the illumination state from the first light source 461 to the second light source 462 (step S12).

[0109] Figure 4 The first switching control is shown. Specifically, in Figure 4 , the vertical axis represents the light quantity of the light emitted from the first light source 461 and the second light source 462, and the horizontal axis represents time.

[0110] As Figure 4 shown in, in the first switching control according to the first embodiment, after a time reference has elapsed since the first light source 461 is turned off, the second light source 462 is turned on. The time reference is the same as the time reference used in the second switching control and is 0.25 [s].

[0111] According to the first embodiment described above, the following effects are exhibited.

[0112] The subject observation system 1 (light source device 6) according to the first embodiment performs first switching control, in which after a time reference (0.25 [s]) has elapsed since the first light source 461 is turned off, the second light source 462 is turned on. Further, the subject observation system 1 (light source device 6) performs second switching control, in which after a time reference (0.25 [s]) has elapsed since the second light source 462 is turned off, the first light source 461 is turned on. That is, when switching between pulsed light (laser) and white light (LED light), the pulsed light (laser) and white light (LED) light are not mixed during the time reference (0.25 [s]). Thus, the subject observation system 1 does not move from categories 2, 2M, or 3R in the wavelength range of 400 nm to 700 nm, which do not require wearing protective glasses, to categories that require wearing protective glasses (for example, categories 3B and 4).

[0113] Therefore, the subject observation system 1 (light source device 6) according to the first embodiment can ensure the light quantity of the emitted light while ensuring safety.

[0114] (Second Embodiment)

[0115] Next, the second embodiment will be described.

[0116] In the following description, the same reference numerals are attached to configurations similar to those of the first embodiment described above, and their detailed descriptions are omitted or simplified.

[0117] Figure 5 is a block diagram showing the subject observation system 1A according to the second embodiment.Figure 6 is a flowchart showing a light source control method executed by the control device 4.

[0118] As Figure 5 shown, the subject observation system 1A according to the second embodiment is obtained by adding the second light quantity detection unit 468 to the light source device main body 46 of the subject observation system 1 described in the above-described first embodiment.

[0119] The second light quantity detection unit 468 corresponds to the light quantity detection unit according to the present disclosure. For example, the second light quantity detection unit 468 includes a photodiode or the like and is installed in the second light guide path 464. Then, the second light quantity detection unit 468 receives a part of the white light (LED light) emitted from the second light source 462 and following the second light guide path 464, and detects the light quantity of the white light (LED light) under the control of the control unit 47.

[0120] Then, as Figure 6 shown, the control device 4 according to the second embodiment executes a light source control method different from the light source control method described in the above-described first embodiment.

[0121] As Figure 6 shown, in the light source control method according to the second embodiment ( Figure 2 ), steps S4A, S7A, and S12A are adopted instead of steps S4, S7, and S12, and step S1A is added to the light source control method described in the above-described first embodiment. Accordingly, only steps S1A, S4A, S7A, and S12A will be mainly described below.

[0122] Step S7A is executed simultaneously with step S1.

[0123] Specifically, in step S7A, the light source control unit 472 controls the operations of each of the first light quantity detection unit 467 and the second light quantity detection unit 468, and starts detecting the light quantity of each of the pulsed light (laser) and the white light (LED light). Then, the control unit 47 proceeds to step S2.

[0124] In the second embodiment, when it is determined that the first user operation has been executed (step S3: YES), the control unit 47 proceeds to step S5. Then, simultaneously with step S5, the light source control unit 472 executes a second switching control for switching the illumination state from the second light source 462 to the first light source 461 (step S4A).

[0125] Figure 7 is a flowchart showing the second switching control. Figure 8 shows the second switching control. Specifically, in Figure 8In the graph, the horizontal axis represents the amount of light emitted from the first light source 461 and the second light source 462, and the horizontal axis represents time.

[0126] First, as in step S8, the light source control unit 472 converts the total amount of light detected by the first light amount detection unit 467 and the second light amount detection unit 468 from a time point earlier than the current time by a time reference (0.25 [s]) to the distal emission light amount. Further, the light source control unit 472 calculates the exposure emission amount (AE) by using the distal emission light amount, the beam divergence (design value), etc. (step S41).

[0127] As in step S9, after step S41, the light source control unit 472 compares the exposure emission amount (AE) calculated in step S41 with a specific threshold value (step S42). As in step S10, the light source control unit 472 adjusts the amount of pulsed light (laser) emitted from the first light source 461 at the current time so that the exposure emission amount does not exceed the specific threshold value (step S43).

[0128] The above-described steps S41 to S43 are repeatedly executed at specific time intervals during the period after the second light source 462 is turned off and a time reference (0.25 [s]) has elapsed. Thus, as Figure 8 shown, during the above-described period, the amount of pulsed light (laser) emitted from the first light source 461 gradually increases.

[0129] Then, after step S4A, the control unit 47 proceeds to step S6. It should be noted that in Figure 7 and Figure 8 the illumination state of the first light source 461 in step S6 is described as "normal" to distinguish this state from the illumination state of the first light source 461 in step S4A.

[0130] Further, after step S6, the control unit 47 proceeds to step S8.

[0131] When it is determined that the second user operation has been performed (step S11: Yes), step S1A is executed.

[0132] Specifically, as in step S1, in step S1A, the control unit 47 sets the subject observation system 1A to the normal observation mode. Then, simultaneously with step S1A, the light source control unit 472 executes the first switching control for switching the illumination state from the first light source 461 to the second light source 462 (step S12A).

[0133] Figure 9 is a flowchart showing the first switching control. Figure 10 shows the first switching control. Specifically, in Figure 10In this case, the horizontal axis represents the amount of light emitted from the first light source 461 and the second light source 462, and the horizontal axis represents time.

[0134] First, as in step S41, the light source control unit 472 converts the total amount of light detected by the first light amount detection unit 467 and the second light amount detection unit 468 from a time point earlier than the current time by a time reference (0.25 [s]) to the current time into the distal emission light amount. Further, the light source control unit 472 calculates the exposure emission amount (AE) by using the distal emission light amount, the beam divergence (design value), etc. (step S121).

[0135] As in step S42, after step S121, the light source control unit 472 compares the exposure emission amount (AE) calculated in step S121 with a specific threshold value (step S122). As in step S43, the light source control unit 472 adjusts the amount of white light (LED light) emitted from the second light source 462 at the current time so that the exposure emission amount does not exceed a specific threshold value (step S123).

[0136] The above steps S121 to S123 are repeatedly executed at specific time intervals during the period after the first light source 461 is turned off and a time reference (0.25 [s]) has elapsed. Thus, as Figure 10 shown, during the above cycle, the amount of white light (LED light) emitted from the second light source 462 gradually increases.

[0137] Then, after step S12A, the control unit 47 returns to step S2. It should be noted that in Figure 7 and Figure 10 , the illumination state of the second light source 462 in step S2 is described as "normal" to distinguish this state from the illumination state of the second light source 462 in step S12A.

[0138] According to the above-described second embodiment, the following effects are exhibited.

[0139] The subject observation system 1A (light source device 6) according to the first embodiment performs first switching control. In the first switching control, within a period after the first light source 461 is turned off and the time reference has elapsed, the light quantity of the second light source 462 is adjusted based on the total amount of light detected by the first light quantity detection unit 467 and the second light quantity detection unit 468 from a time point earlier than the current time by the time reference (0.25 [s]) to the current time and the exposure emission limit (AEL) set according to the category of the subject observation system 1A. Further, the subject observation system 1A (light source device 6) performs second switching control. In the second switching control, within a period when the time reference has elapsed after the second light source 462 is turned off, the light quantity of the first light source 461 is adjusted based on the total amount of light detected by the first light quantity detection unit 467 and the second light quantity detection unit 468 from a time point earlier than the current time by the time reference (0.25 [s]) to the current time and the exposure emission limit (AEL) set according to the category of the subject observation system 1A. That is, when switching between pulsed light (laser) and white light (LED light), even if the pulsed light (laser) and white light (LED) light are not mixed during the time reference (0.25 [s]), the exposure emission amount (AE) does not exceed a specific exposure emission limit (AEL). Thereby, the subject observation system 1A does not move from categories 2, 2M, or 3R in the wavelength range of 400 nm to 700 nm, which do not require wearing protective glasses, to categories that require wearing protective glasses (for example, categories 3B and 4).

[0140] Therefore, the subject observation system 1A (light source device 6) according to the second embodiment can ensure the light quantity of the emitted light while ensuring safety.

[0141] Specifically, different from the first embodiment described above, in the second embodiment, when switching between pulsed light (laser) and white light (LED light), without providing an on-period of the time reference, the pulsed light (laser) and white light (LED light) are mixed during the time reference (0.25 [s]). Thereby, the subject can be irradiated with the emitted light at an early stage during the switching, and a user such as a doctor can check the captured image on the screen of the display device 5 based on the emitted light, thereby improving convenience.

[0142] (Other Embodiments)

[0143] Although embodiments for completing the present disclosure have been described so far, the present disclosure should not be limited only to the first and second embodiments described above.

[0144] In the above-described first and second embodiments, although the light source device 6 according to the present disclosure is installed in the subject observation systems 1 and 1A in which the endoscope 2 is a flexible endoscope, it is not limited thereto. For example, the light source device 6 according to the present disclosure can be installed in a subject observation system in which the endoscope 2 is a rigid endoscope. Further, the light source device 6 according to the present disclosure can be installed in a subject observation system, such as an operating microscope for magnifying and observing a predetermined visual field area in a subject (living body), or installed in a subject (living body surface) (for example, see JP2016-42981A).

[0145] Although the light source device 6 according to the above-described first embodiment is provided with the first light quantity detection unit 467, the light source device 6 can have a configuration without the first light quantity detection unit 467.

[0146] Although the light source device 6 according to the above-described second embodiment is provided with the first light quantity detection unit 467 and the second light quantity detection unit 468 (two), it is not limited thereto. The light source device 6 can adopt a configuration in which, after the first light guide path 463 and the second light guide path 464 are joined together, only one light quantity detection unit is installed in the optical path. That is, a configuration in which one light quantity detection unit detects the light quantities of pulsed light (laser) and white light (LED light) can be adopted.

[0147] In the above-described first and second embodiments, although the second light source 462 includes an LED, it is not limited thereto. Like the first light source 461, the second light source 462 can include a semiconductor laser. Further, although light is continuously emitted from the second light source 462, it is not limited thereto. Like the first light source 461, pulsed light can be emitted.

[0148] In the above-described first and second embodiments, although the subject observation systems 1 and 1A observe the vocal cords by stroboscopic observation, it is not limited thereto. The subject observation systems 1 and 1A can observe the subject by special light. Examples of observation by special light include NBI, IRI, AFI, PDD, etc.

[0149] NBI is a method for observing the state of blood vessels in the superficial layer and deeper layer of the mucosa. In this method, narrow-band illumination light having center wavelengths of 415 nm and 540 nm is applied, and the absorption difference of hemoglobin for light of each wavelength is used.

[0150] IRI is a method for diagnosing the presence or absence of blood flow. In the method, a medical agent called indocyanine green (ICG) having an absorption peak in near-infrared light with a wavelength of about 805 nm in the blood is intravenously injected as a contrast medium, and excitation light having a central wavelength of about 805 nm is applied, and fluorescence from the ICG is observed.

[0151] AFI is a method for diagnosing a tumor part. In the method, a fluorescent agent is preliminarily administered to a subject, a fluorescence image emitted from the subject is observed by applying excitation light, and the presence or absence of the fluorescence image or its shape is observed.

[0152] PDD is a method for acquiring an image by using a specific property, in which it is easy to distinguish cancer cells from normal cells. In terms of the property, although a solution of 5-aminolevulinic acid (5-ALA) taken by a patient is metabolized into a blood raw material (heme) in normal tissues in the body, however, the solution is not metabolized in cancer cells and accumulates as an intermediate substance called PpIX. When blue light (central wavelength of 410 nm) is applied to PpIX, PpIX emits red fluorescence (peak wavelength of 630 nm).

[0153] In the light source device 6 according to the first embodiment and the second embodiment described above, the illumination state can be switched from the first light source 461 to the second light source 462, and at the same time, the illumination state can be switched from the second light source 462 to the first light source 461, but it is not limited thereto. For example, a light source device that can only switch the illumination state from the first light source 461 to the second light source 462 can be adopted. In this case, only the first switching control among the first switching control and the second switching control needs to be executed. Further, for example, a light source device that can only switch the illumination state from the second light source 462 to the first light source 461 can be adopted. In this case, only the second switching control among the first switching control and the second switching control needs to be executed.

[0154] In the first switching control according to the first embodiment described above, the second light source 462 can be turned on after a time exceeding the time reference (0.25 [s]) has elapsed after the first light source 461 is turned off. Similarly, in the second switching control according to the second embodiment described above, the first light source 461 can be turned on after a time exceeding the time reference (0.25 [s]) has elapsed after the second light source 462 is turned off.

[0155] It should be noted that the following configurations also belong to the technical scope of the present disclosure.

[0156] (1) A light source device according to the present disclosure includes: a first light source configured to emit laser light; a second light source configured to emit light; and a light source control unit configured to control the operations of the first light source and the second light source; wherein the light source control unit is configured to perform each of a first switching control and a second switching control on the laser light emitted from the first light source and irradiated on the subject based on a time reference according to a category specified by a laser standard indicating the safety standard of the laser product, the first switching control means switching the illumination state from the first light source to the second light source, and the second switching control means switching the illumination state from the second light source to the first light source.

[0157] (2) The light source device according to (1), wherein, in the first switching control, after a time equal to or greater than the time reference has elapsed since the first light source was turned off, the second light source is turned on; and in the second switching control, after a time equal to or greater than the time reference has elapsed since the second light source was turned off, the first light source is turned on.

[0158] (3) The light source device according to (1) further includes: a light quantity detection unit configured to detect the light quantity of the laser light emitted from the first light source and the light quantity of the light emitted from the second light source; wherein, in the first switching control, within the period after the first light source is turned off and a time equal to the time reference has elapsed, the light quantity of the second light source is adjusted based on the total amount of light detected by the light quantity detection unit from a time point earlier than the current time by the time reference to the current time and an exposure emission limit set according to the category; and in the second switching control, within the period after the second light source is turned off and a time equal to the time reference has elapsed, the light quantity of the first light source is adjusted based on the total amount of light detected by the light quantity detection unit from a time point earlier than the current time by the time reference to the current time and the exposure emission limit.

[0159] (4) A light source device includes: a first light source configured to emit laser light; a second light source configured to emit light; and a light source control unit configured to control the operations of the first light source and the second light source; wherein the light source control unit is configured to perform a switching control for switching the illumination state from the first light source to the second light source on the laser light emitted from the first light source and irradiated on the subject based on a time reference according to a category specified by a laser standard indicating the safety standard of the laser product.

[0160] (5) The light source device according to (4), wherein, in the switching control, after a time equal to or greater than the time reference has elapsed since the first light source was turned off, the second light source is turned on.

[0161] (6) The light source device according to (4) further includes: a light quantity detection unit configured to detect the light quantity of the laser emitted from the first light source and the light quantity of the light emitted from the second light source; wherein, in the switching control, within the period after the first light source is turned off and after a time reference has elapsed, the light quantity of the second light source is adjusted based on the total amount of light detected by the light quantity detection unit from a time point earlier than the current time by the time reference to the current time and the exposure emission limit set according to the category.

[0162] (7) A light source device includes: a first light source configured to emit a laser; a second light source configured to emit light; and a light source control unit configured to control the operations of the first light source and the second light source; wherein, the light source control unit is configured to perform switching control to switch the illumination state from the second light source to the first light source on the laser emitted from the first light source and irradiated on the subject based on a time reference according to the category specified by a laser standard indicating the safety standard of the laser product.

[0163] (8) The light source device according to (7), wherein, in the switching control, after a time longer than the time reference has elapsed after the second light source is turned off, the first light source is turned on.

[0164] (9) The light source device according to (7) further includes: a light quantity detection unit configured to detect the light quantity of the laser emitted from the first light source and the light quantity of the light emitted from the second light source; wherein, in the switching control, within the period after the second light source is turned off and after a time reference has elapsed, the light quantity of the first light source is adjusted based on the total amount of light detected by the light quantity detection unit from a time point earlier than the current time by the time reference to the current time and the exposure emission limit set according to the category.

[0165] (10) The light source device according to any one of (1) to (9), wherein the category refers to category 2 or category 2M specified by the laser standard or category 3R in the wavelength range of 400 nm to 700 nm.

[0166] (11) The light source device according to any one of (1) to (10), wherein the light source control unit is configured to emit the laser from the first light source in a pulse form.

[0167] (12) A subject observation system includes: the light source device according to any one of (1) to (11); and an imaging device configured to capture an image of the subject irradiated with the light from the light source device.

[0168] Symbol Explanation

[0169] 1, 1A Subject observation system

[0170] 2 Endoscope

[0171] 3 Voice input device

[0172] 4 Control device

[0173] 4a Voice input terminal

[0174] 5 Display device

[0175] 6 Light source device

[0176] 21 Insertion part

[0177] 22 Operation unit

[0178] 23 General-purpose cord

[0179] 23a Connector

[0180] 24 Light guide

[0181] 25 Illumination lens

[0182] 26 Imaging unit

[0183] 27 Cable

[0184] 31 Cord

[0185] 41 Input unit

[0186] 42 Vibration frequency detection unit

[0187] 43 Memory

[0188] 44 Image processing unit

[0189] 45 Display control unit

[0190] 46 Light source device main body

[0191] 47 Control unit

[0192] 261 Optical system

[0193] 262 Imaging element

[0194] 263 Light receiving unit

[0195] 264 Reading unit

[0196] 461 First light source

[0197] 462 Second light source

[0198] 463 First light guide path

[0199] 464 Second light guide path

[0200] 465 First light source driver

[0201] 466 Second light source driver

[0202] 467 First light quantity detection unit

[0203] 468 Second light quantity detection unit

[0204] 471 Imaging control unit

[0205] 472 Light source control unit.

Claims

1. A light source device, comprising: a first light source configured to emit laser light; a second light source configured to emit light; and a light source control unit configured to control operations of the first light source and the second light source; wherein the light source control unit is configured to perform switching control for switching an illumination state from the first light source to the second light source on the laser light that is emitted from the first light source and irradiated on a subject based on a time reference according to a category defined by a laser standard indicating a safety standard for laser products.

2. The light source device according to claim 1, further comprising: a light quantity detection unit configured to detect a light quantity of the laser light emitted from the first light source and a light quantity of the light emitted from the second light source; wherein, in the switching control, within a period after the first light source is turned off and the time reference has elapsed, the light quantity of the second light source is adjusted based on a total amount of light detected by the light quantity detection unit from a time point earlier than the current time by the time reference to the current time.

3. The light source device according to claim 2, wherein in the switching control, the light quantity of the second light source is adjusted based on an exposure emission limit set according to the category.

4. The light source device according to claim 1, wherein the light quantity controlled by the switching control corresponds to a laser class for which a user does not need to wear protective glasses.

5. The light source device according to claim 1, wherein the category refers to category 2 or category 2M defined by the laser standard or category 3R in a wavelength range of 400 nm to 700 nm.

6. The light source device according to claim 1, wherein the light source control unit is configured to emit the laser light from the first light source in a pulse form.

7. A light source device, comprising: a first light source configured to emit laser light; a second light source configured to emit light; and a light source control unit configured to control operations of the first light source and the second light source; wherein the light source control unit is configured to perform switching control for switching an illumination state from the second light source to the first light source on the laser light that is emitted from the first light source and irradiated on a subject based on a time reference according to a category defined by a laser standard indicating a safety standard for laser products.

8. The light source device according to claim 7, further comprising: a light quantity detection unit configured to detect a light quantity of the laser light emitted from the first light source and a light quantity of the light emitted from the second light source; wherein, in the switching control, within a period after the second light source is turned off and the time reference has elapsed, the light quantity of the first light source is adjusted based on a total amount of light detected by the light quantity detection unit from a time point earlier than the current time by the time reference to the current time.

9. The light source device according to claim 8, wherein in the switching control, the light quantity of the first light source is adjusted based on an exposure emission limit set according to the category.

10. The light source device according to claim 7, wherein the light quantity controlled by the switching control corresponds to a laser class for which a user does not need to wear protective glasses.

11. The light source device according to claim 7, wherein, the category refers to Category 2 or Category 2M specified by the laser standard or Category 3R in the wavelength range of 400 nm to 700 nm.

12. The light source device according to claim 7, wherein, the light source control unit is configured to emit laser light from the first light source in the form of pulses.

13. A subject observation system, comprising: a light source device including: a first light source configured to emit laser light; a second light source configured to emit light; and a light source control unit configured to control the operations of the first light source and the second light source; wherein, the light source control unit is configured to perform switching control for switching the illumination state from the first light source to the second light source on the laser light that is emitted from the first light source and irradiated on the subject based on a time reference according to the category specified by the laser standard indicating the safety standard of laser products; and an imaging device configured to capture an image of the subject irradiated with light from the light source device.

14. The subject observation system according to claim 13, wherein the light source device further comprises: a light quantity detection unit configured to detect the light quantity of the laser light emitted from the first light source and the light quantity of the light emitted from the second light source; wherein, in the switching control, within the period after the first light source is turned off and after the time reference has elapsed, the light quantity of the second light source is adjusted based on the total amount of light detected by the light quantity detection unit from a time point earlier than the current time by the time reference to the current time.

15. A subject observation system, comprising: a light source device including: a first light source configured to emit laser light; a second light source configured to emit light; and a light source control unit configured to control the operations of the first light source and the second light source; wherein, the light source control unit is configured to perform switching control for switching the illumination state from the second light source to the first light source on the laser light that is emitted from the first light source and irradiated on the subject based on a time reference according to the category specified by the laser standard indicating the safety standard of laser products; and an imaging device configured to capture an image of the subject irradiated with light from the light source device.

16. The subject observation system according to claim 15, wherein the light source device further comprises: a light quantity detection unit configured to detect the light quantity of the laser light emitted from the first light source and the light quantity of the light emitted from the second light source; wherein, in the switching control, within the period after the second light source is turned off and after the time reference has elapsed, the light quantity of the first light source is adjusted based on the total amount of light detected by the light quantity detection unit from a time point earlier than the current time by the time reference to the current time.

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