Medical control device and medical observation system

Abstract

A medical control device 9 comprises: a light source control unit 941 that causes first light to be emitted from a light source device 3 to an observation target; and an imaging control unit 942 that causes second light, which is light based on the first light and returns from the observation target, to be imaged by a rolling shutter type imaging element 531 in which a plurality of pixels are two-dimensionally arranged in units of horizontal lines. The light source control unit 941 determines the period of the light emission pattern of the first light from the light source device 3, on the basis of the exposure time of the imaging element 531, and causes the first light to be emitted.

Description

Medical control device and medical observation system ,

[0004]

[0001] The present disclosure relates to a medical control device and a medical observation system.

[0002] Conventionally, a medical observation system has been known that irradiates a first light such as excitation light, which is narrow-band light emitted from a light source device, or white light, which is broadband light, onto an observation target (a subject such as a person), and observes a second light that is the return light from the observation target based on the first light (for example, see Patent Document 1). In the medical observation system described in Patent Document 1, excitation light is adopted as the first light, and fluorescence (hereinafter referred to as observation target fluorescence), which is the return light emitted from the substance contained in the observation target by the irradiation of the excitation light, can be observed. According to such fluorescence observation, it is possible to grasp a tissue state that is difficult to recognize through the observation target fluorescence. Therefore, fluorescence observation can be used for various purposes and applications such as identifying a lesion part.

[0003] Japanese Patent Application Laid-Open No. 2023-119524

[0004] Here, in the medical observation system described in Patent Document 1, the brightness of the image is adjusted by changing the exposure time of the imaging element that captures the observation target fluorescence (hereinafter referred to as electronic shutter control). However, when performing electronic shutter control, there is a problem that uneven brightness may occur in the generated image if the light amount of the first light (second light) changes over time. Therefore, there is a demand for a technology that can generate an image suitable for observation.

[0005] The present disclosure has been made in view of the above, and an object thereof is to provide a medical control device and a medical observation system that can generate an image suitable for observation.

[0006] To solve the above-mentioned problems and achieve the objective, the medical control device according to this disclosure comprises a light source control unit that emits a first light from a light source device toward an object to be observed, and an imaging control unit that causes a second light, which is the reflected light from the object to be observed based on the first light, to be imaged by a rolling shutter type image sensor in which a plurality of pixels are arranged in a two-dimensional manner in units of horizontal lines, wherein the light source control unit determines the period of the emission pattern of the first light from the light source device based on the exposure time of the image sensor and emits the first light.

[0007] Furthermore, the medical control device according to this disclosure includes a light source control unit that emits a first light from a light source device toward an object to be observed, and an imaging control unit that causes a second light, which is the reflected light from the object to be observed based on the first light, to be imaged by a rolling shutter type image sensor in which a plurality of pixels are arranged in a two-dimensional manner in units of horizontal lines, wherein the light source control unit emits the first light from the light source device such that the sum of the exposure amounts of the first light at exposure times for at least two or more horizontal lines on the image sensor approaches each other.

[0008] Furthermore, the medical observation system according to this disclosure comprises a light source device that emits a first light, a light source control unit that emits the first light from the light source device toward an object to be observed, a rolling shutter type image sensor in which a plurality of pixels are arranged in two dimensions in units of horizontal lines, and an imaging control unit that causes the image sensor to image the second light, which is the reflected light from the object to be observed based on the first light, wherein the light source control unit determines the period of the emission pattern of the first light from the light source device based on the exposure time of the image sensor and emits the first light.

[0009] According to the medical control device and medical observation system described herein, it is possible to generate images suitable for observation.

[0010] Figure 1 is a diagram illustrating the configuration of a medical observation system according to an embodiment. Figure 2 is a diagram illustrating the function of a light source device. Figure 3 is a block diagram illustrating the configuration of a camera head and a control device. Figure 4 is a diagram illustrating the function of the first image sensor. Figure 5 is a diagram illustrating the conventional problems. Figure 6 is a diagram illustrating the effects of the embodiment. Figure 7 is a diagram illustrating the effects of the embodiment. Figure 8 is a diagram illustrating the effects of the embodiment. Figure 9 is a diagram illustrating the effects of the embodiment. Figure 10 is a diagram illustrating the effects of the embodiment. Figure 11 is a diagram illustrating the effects of the embodiment. Figure 12 is a diagram illustrating the effects of the embodiment. Figure 13 is a diagram illustrating modification 1 of the embodiment. Figure 14 is a diagram illustrating modification 1 of the embodiment. Figure 15 is a diagram illustrating modification 1 of the embodiment. Figure 16 is a diagram illustrating modification 1 of the embodiment. Figure 17 is a diagram illustrating modification 1 of the embodiment. Figure 18 is a diagram illustrating modification 2 of the embodiment. Figure 19 is a diagram illustrating modification 3 of the embodiment. Figure 20 is a diagram illustrating modification 4 of the embodiment. Figure 21 is a diagram illustrating modification 4 of the embodiment.

[0011] The embodiments for implementing this disclosure (hereinafter referred to as "embodiments") will be described below with reference to the drawings. However, the embodiments described below do not limit this disclosure. Furthermore, the same parts are denoted by the same reference numerals in the drawings.

[0012] [Configuration of the Medical Observation System] Figure 1 shows the configuration of the medical observation system 1 according to this embodiment. In this embodiment, the medical observation system 1 is a medical endoscope system that uses an endoscope to observe the observation target OB (inside the body). As shown in Figure 1, the medical observation system 1 comprises an insertion unit 2, a light source device 3, a light guide 4, a camera head 5, a first transmission cable 6, a display device 7, a second transmission cable 8, a control device 9, and a third transmission cable 10.

[0013] In this embodiment, the insertion section 2 is made of a rigid endoscope. That is, the insertion section 2 has an elongated shape that is either entirely rigid or partially flexible with other parts rigid, and is inserted into the observation target OB. Inside the insertion section 2, there is an optical system made of one or more lenses that collects the reflected light (image of the subject) from the observation target OB.

[0014] Furthermore, an excitation light cut filter 22 (Figure 1) is provided at the base end (eyepiece 21) of the insertion section 2 to partially, substantially, or completely suppress the excitation light contained in the focused reflected light (subject image), which will be described later. Note that the excitation light cut filter 22 is not limited to the insertion section 2, but may also be provided inside the camera head 5.

[0015] One end of the light guide 4 is connected to the light source device 3. The light source device 3 includes a first light source 31 (Figure 1) that supplies first light to the one end of the light guide 4 under the control of the control device 9. In this embodiment, the first light is excitation light (narrowband light) that excites the substance contained in the object to be observed OB. The wavelength band of the excitation light may include the visible wavelength band, or it may be the infrared wavelength band or the ultraviolet wavelength band excluding the visible wavelength band. The first light source 31 may be an LED (Light Emitting Diode) or a semiconductor laser. The number of first light sources 31 that emit the first light may be one or more. Furthermore, the first light may be light including the visible wavelength band (white light). The light source device 3 may also be configured to have two or more light sources, such as a light source that emits excitation light and a light source that emits white light.

[0016] Figure 2 is a diagram illustrating the function of the light source device 3. Specifically, Figure 2 shows an image of the emission of excitation light emitted from the light source device 3, with the vertical axis representing the light intensity (amount of emission) of the excitation light and the horizontal axis representing time. The light source device 3 is configured to change the amount of excitation light emitted, as shown in Figure 2, under the control of the control device 9. Specifically, as shown in Figure 2(a), the light source device 3 is made capable of continuously emitting excitation light (steady emission) without changing the amount of excitation light emitted over time, under the control of the control device 9. Furthermore, as shown in Figure 2(b), the light source device 3 is made capable of continuously emitting excitation light while changing the amount of excitation light emitted over time, under the control of the control device 9. In addition, as shown in Figure 2(c), the light source device 3 is made capable of intermittently emitting excitation light (pulsed emission) under the control of the control device 9.

[0017] Examples of substances contained in the observed object OB that are excited by the excitation light include drugs or fluorescent dyes applied to the observed object OB, or fluorescent substances derived from the observed object OB that constitute the observed object OB itself.

[0018] Examples of the above-mentioned drugs administered to the observed OB include "5-ALA (PP-IX)", "ADS780WS", "ADS830WS", "aggregation-induced emission dots allophycocyanin (APC)", "boron-dipyrromethane (BODIPY)", "CLR 1502", "Flavins", "fluorescamine", "Fluorescein", "fluoro-gold", "green fluorescence protein", "ICG (indocyanine green)", "IRDye 78", "IR-PEG nanoparticles", "Isothiocyanate", "rose bengal", "SGM-101", and "trypan blue".

[0019] Furthermore, the fluorescent dyes mentioned above that can be applied to the observed OB include: "coumarine", "Cy3", "DyLight547", "GE3126", "metal nanoclusters", "oxacarbocyanine", "Rhodamine", "Riboflavin", "fluorescein", "AlexaFluor 488", "AlexaFluor660", "AlexaFluor680", "AlexaFluor700", "Cy5", "Cy5.5", "Dy677", "Dy682", "Dy752", "DyLight647", "HiLyte Fluor 647", "HiLyte Fluor 680", "IRDye 700DX", "methylene blue", "Porphyrins", "Porphysomes", "VivoTag-680", "VivoTag-S680", "AlexaFluor750", "AlexaFluor790", "carbocyanine", "conjugated copolymers", "CW800-CA", "Cy7", "Cy7.5", and "cyanine". Examples include "dyes", "Dy780", "HiLyte Fluor 750", "Indocarbocyanine", "IR-786", "IRDye 800CW", "IRDye 800RS", "IRDye 800BK", "Nervelight", "OTL-38 (Pafolacianine)", "Polymethine", "VivoTag-S750", "ASP5354", "Xanthene", and "LUM-015".

[0020] Furthermore, examples of fluorescent substances derived from the observed OB that constitute the observed OB itself include "collagen," "elastin," and "NADH."

[0021] In this embodiment, the light source device 3 is configured separately from the control device 9, but it is not limited to this configuration, and it may also be configured to be housed in the same enclosure as the control device 9.

[0022] One end of the light guide 4 is detachably connected to the light source device 3. The other end of the light guide 4 is detachably connected to the insertion section 2. The light guide 4 propagates the excitation light supplied from the light source device 3 from one end to the other and supplies it to the insertion section 2. The excitation light supplied to the insertion section 2 is emitted from the tip of the insertion section 2 and irradiates the object to be observed OB. The reflected light from the object to be observed OB (the subject image (the second light according to this disclosure)) is focused by the optical system in the insertion section 2. This reflected light includes not only the excitation light reflected by the object to be observed OB, but also fluorescence (hereinafter referred to as object fluorescence) emitted from a substance contained in the object to be observed OB when the excitation light irradiates the object to be observed and the substance is excited.

[0023] The camera head 5 is detachably connected to the eyepiece 21 of the insertion section 2. Under the control of the control device 9, the camera head 5 captures the reflected light that is focused in the insertion section 2 and passes through the excitation light cut filter 22, generating a pixel signal. For the sake of explanation, the pixel signal generated by capturing this reflected light will be referred to as the captured image or fluorescence image below. The detailed configuration of the camera head 5 will be explained later in "Camera Head Configuration".

[0024] One end of the first transmission cable 6 is detachably connected to the control device 9 via connector CN1 (Figure 1). The other end of the first transmission cable 6 is detachably connected to the camera head 5 via connector CN2 (Figure 1). Note that the connector CN2 is not limited to a configuration in which it is detachably connected to the camera head 5, but may also be fixed to the camera head 5. The first transmission cable 6 transmits captured images (fluorescence images) etc. output from the camera head 5 to the control device 9, and also transmits control signals, synchronization signals, clocks, power etc. transmitted from the control device 9 to the camera head 5, respectively.

[0025] The captured images (fluorescent images, etc.) transmitted from the camera head 5 to the control device 9 via the first transmission cable 6 may be transmitted as optical signals or as electrical signals. The same applies to the transmission of control signals, synchronization signals, and clock signals from the control device 9 to the camera head 5 via the first transmission cable 6.

[0026] The display device 7 is composed of a display using liquid crystal or organic EL (Electro Luminescence), and under the control of the control device 9, it displays an image based on a video signal from the control device 9.

[0027] One end of the second transmission cable 8 is detachably connected to the display device 7. The other end of the second transmission cable 8 is detachably connected to the control device 9. The second transmission cable 8 transmits the video signal processed by the control device 9 to the display device 7.

[0028] The control device 9 corresponds to the medical control device described herein. This control device 9 includes controllers such as a CPU (Central Processing Unit) and an MPU (Micro Processing Unit), and comprehensively controls the operation of the light source device 3, the camera head 5, and the display device 7. The control device 9 is not limited to a CPU or MPU, but may also include an ASIC (Application Specific Integrated Circuit), FPGA (Field-Programmable Gate Array), or GPU (Graphics Processing Unit). The detailed configuration of the control device 9 will be described later in the section "Configuration of the Control Device".

[0029] One end of the third transmission cable 10 is detachably connected to the light source device 3. The other end of the third transmission cable 10 is detachably connected to the control device 9. The third transmission cable 10 transmits control signals from the control device 9 to the light source device 3.

[0030] [Camera Head Configuration] Next, the configuration of the camera head 5 will be described. Figure 3 is a block diagram showing the configuration of the camera head 5 and the control device 9. As shown in Figure 3, the camera head 5 comprises a lens unit 51, an imaging unit 53, and a communication unit 54.

[0031] The lens unit 51 is composed of one or more lenses. The lens unit 51 focuses light at the insertion section 2, and the reflected light, which has passed through the excitation light cut filter 22, is imaged onto the imaging surface of the first image sensor 531 in the imaging section 53.

[0032] The imaging unit 53 captures an image of the observation target OB under the control of the control device 9. As shown in Figure 3, the imaging unit 53 comprises a first image sensor 531 and a signal processing unit 533.

[0033] The first image sensor 531 corresponds to the image sensor according to this disclosure. This first image sensor 531 receives a subject image and converts it into an electrical signal (analog signal). In this embodiment, the first image sensor 531 is composed of a CMOS (Complementary Metal Oxide Semiconductor), which is a rolling shutter type image sensor in which a plurality of pixels are arranged in a two-dimensional manner in units of horizontal lines. Note that the first image sensor 531 is not limited to one, but a configuration in which two or more are provided may be adopted.

[0034] Figure 4 is a diagram illustrating the function of the first image sensor 531. Specifically, in Figure 4, the vertical axis shows the horizontal lines of the first image sensor 531 (the top row shows the uppermost horizontal line (the first horizontal line), and the bottom row shows the lowermost horizontal line (the final line)), and the horizontal axis shows time. The largest approximately parallelogram region is the region that contributes to the generation of the fluorescence image when the exposure time is maximized (for the entire frame (field)). In this embodiment, the first image sensor 531 is configured to allow the opening amount of the electronic shutter (exposure time) to be changed under the control of the control device 9. In Figure 4, the approximately parallelogram region with dots indicates the region showing the effective exposure time. The approximately parallelogram region without dots indicates the region showing the sweeping away of charge by the electronic shutter.

[0035] The signal processing unit 533, under the control of the control device 9, performs signal processing on the analog signal image (fluorescence image) generated by the first image sensor 531 and outputs a digital signal image (fluorescence image). For example, the signal processing unit 533 performs signal processing on the image image (analog signal) generated by the first image sensor 531, such as removing reset noise, multiplying the analog signal by an analog gain to amplify the analog signal, and A / D conversion.

[0036] The communication unit 54 functions as a transmitter that transmits the captured images (fluorescence images) output sequentially from the signal processing unit 533 to the control device 9 via the first transmission cable 6. This communication unit 54 is configured as a high-speed serial interface that communicates captured images (fluorescence images) with the control device 9 via the first transmission cable 6 at a transmission rate of 1 Gbps or higher.

[0037] [Configuration of the control device] Next, the configuration of the control device 9 will be described with reference to Figure 2. As shown in Figure 3, the control device 9 comprises a communication unit 91, an image memory 92, a processing module 93, a control unit 94, an input unit 95, an output unit 96, and a storage unit 97.

[0038] The communication unit 91 functions as a receiver that receives captured images (fluorescence images) sequentially transmitted from the camera head 5 (communication unit 54) via the first transmission cable 6. This communication unit 91 is configured, for example, as a high-speed serial interface that communicates captured images (fluorescence images) with the communication unit 54 at a transmission rate of 1 Gbps or higher.

[0039] The image memory 92 is composed of, for example, DRAM (Dynamic Random Access Memory). This image memory 92 is capable of temporarily storing multiple frames of captured images (fluorescence images) sequentially output from the camera head 5 (communication unit 54).

[0040] The processing module 93 processes the captured images (fluorescence images) that are sequentially transmitted from the camera head 5 (communication unit 54) and received by the communication unit 91, under the control of the control unit 94. As shown in Figure 3, this processing module 93 comprises a memory controller 931, an image processing unit 932, and a display control unit 933.

[0041] The memory controller 931 controls the writing of captured images (fluorescent images) to the image memory 92 and the reading of said captured images (fluorescent images) from the image memory 92. More specifically, the memory controller 931 writes the captured images (fluorescent images) received by the communication unit 91 to the image memory 92, reads said captured images (fluorescent images) from the image memory 92 at a specific timing, and inputs them to the image processing unit 932.

[0042] The image processing unit 932 performs image processing on the input captured image (fluorescence image). Examples of such image processing include optical black subtraction (clamping), white balance adjustment, demosaicing, color correction matrix processing, gamma correction, YC processing to convert RGB signals into luminance chromatic difference signals (Y, Cb / Cr signals), digital gain adjustment to multiply digital gain, noise reduction, and filtering to enhance structure.

[0043] The display control unit 933 generates a video signal for displaying the captured image (fluorescent image) after the image processing is executed by the image processing unit 932 under the control of the control unit 94. Then, the display control unit 933 outputs the video signal to the display device 7 via the second transmission cable 8. Thereby, the display device 7 displays the captured image (fluorescent image) based on the video signal.

[0044] The control unit 94 is realized by executing various programs stored in the storage unit 97 by a controller such as a CPU or an MPU, controls the operations of the light source device 3, the camera head 5, and the display device 7, and controls the operation of the entire control device 9. Note that the control unit 94 is not limited to a CPU or an MPU, and may be constituted by an ASIC, an FPGA, a GPU, or the like. As shown in FIG. 3, this control unit 94 includes a light source control unit 941 and an imaging control unit 942. The functions of the light source control unit 941 and the imaging control unit 942 in the control unit 94 will be described in "Conventional Problems" and "Light Source Control" described later.

[0045] The input unit 95 is configured using an operation device such as a mouse, a keyboard, and a touch panel, and receives a user operation by a user such as an operator. Then, the input unit 95 outputs an operation signal corresponding to the user operation to the control unit 94. Note that the operation reception unit according to the present disclosure is not limited to the configuration provided in the control device 9 like the input unit 95, and may be, for example, a configuration provided in the camera head 5.

[0046] The output unit 96 is configured using a speaker, a printer, or the like, and outputs various information.

[0047] The storage unit 97 stores programs executed by the control unit 94, information necessary for the processing of the control unit 94, and the like.

[0048] [Problems of the Prior Art] FIG. 5 is a diagram for explaining the problems of the prior art. Specifically, FIG. 5(a) is a diagram corresponding to FIG. 4 and is a diagram for explaining the imaging control by the imaging control unit 942. In FIG. 5(a), the area showing the charge sweeping by the electronic shutter is omitted, and only the area showing the effective exposure time is illustrated. FIG. 5(b) is a diagram corresponding to FIG. 2(b) and is a diagram for explaining the light source control by the light source control unit 941. As shown in FIG. 5(a), the imaging control unit 942 performs imaging control by a so-called rolling shutter method in which the exposure in one frame (field) period of the first image sensor 531 is sequentially started for each horizontal line, and the reading is sequentially performed for each horizontal line after the exposure time has elapsed from the start of exposure. The exposure time is, for example, a time calculated by the control unit 94 to adjust the imaging image to a reference brightness based on the brightness (average value of luminance values, etc.) of a specific area (detection area) in the imaging image (fluorescent image).

[0049] Here, as shown in FIG. 5(a), the exposure start time and the exposure end time are different for each horizontal line of the first image sensor 531. Therefore, even if the exposure time is the same for each horizontal line, the total sum of the exposure amounts for receiving the observation target fluorescence for each horizontal line may be different. In FIG. 5, only the corresponding horizontal lines are shaded (FIG. 5(a)), and only the light emitting portion of the excitation light corresponding to the observation target fluorescence received by the corresponding horizontal line is shaded (FIG. 5(b)). That is, the horizontal line with a large total sum of exposure amounts becomes bright, while the horizontal line with a small total sum of exposure amounts becomes dark. This brightness unevenness for each horizontal line becomes the brightness unevenness in the imaging image (fluorescent image).

[0050] [Regarding Light Source Control] The light source control unit 941 executes the following light source control in order to solve the above-described problems of the prior art.

[0051] Here, when the exposure time is exp, the deviation of the exposure time between horizontal lines is Δt, and the excitation light emitted by the first light source 31 is a function of time Light(t), the total sum of the exposure amounts for the n-th line can be expressed by the following equation (1).

[0052]

[0053] Furthermore, in the first image sensor 531 having N horizontal lines, the condition for solving the aforementioned conventional problem is that the sum of the exposure amounts for all horizontal lines is equal or approaches the same. This condition can be expressed by the following equation (2).

[0054]

[0055] Then, in order to satisfy the conditions shown in equation (2), the light source control unit 941 performs light source control to emit excitation light from the first light source 31 with a light emission pattern Light(t) having a period of exposure time exp. That is, the light emission pattern Light(t) is a light emission pattern that satisfies the following equation (3). Specifically, the light emission pattern Light(t) is a light emission pattern with a period of exposure time exp, and as shown in equation (3), even if the phase shifts by an integer multiple of the exposure time exp, it returns to the original light emission pattern Light(t).

[0056]

[0057] For example, the light source control unit 941 performs light source control as shown below. First, the light source control unit 941 selects a template for the light emission pattern to be generated. Examples of such templates include one in which the exposure time is divided into four segments in chronological order, and when these four segments are numbered in chronological order, the lights are turned on at even-numbered intervals and at odd-numbered intervals.

[0058] Next, the light source control unit 941 acquires the exposure time calculated by the control unit 94.

[0059] Next, the light source control unit 941 generates a light emission pattern based on the selected template and the acquired exposure time. Then, the light source control unit 941 emits excitation light from the first light source 31 using the generated light emission pattern.

[0060] The embodiment described above provides the following effects. Figures 6 and 7 illustrate light source control when the exposure time exp is short. When the exposure time exp is short, it means that the regions indicating effective exposure time do not overlap in time between adjacent frames (fields) (the same applies hereinafter). Figure 6(a) corresponds to Figure 4. In Figure 6(a), dots are used to indicate the region indicating the effective exposure time, and diagonal lines are used to indicate the region indicating charge sweeping by the electron shutter. Figure 6(b) corresponds to Figure 5(b), where the excitation light is emitted in a emission pattern with a period of exposure time exp by the light source control unit 941. Figure 7 is an enlarged view of Figure 6(b) and illustrates the following equation (4).

[0061] First, let's consider the case where the exposure time exp is short. In this case, let's calculate the sum of the exposure amounts for a certain n-th line, where f is the fractional value obtained by dividing (n-1)Δt, which is the exposure start timing for the n-th line, by the exposure time exp. Here, the emission pattern Light(t) is an emission pattern with a period of exposure time exp. Therefore, as shown in Figure 7 and equation (4) below, the sum of the exposure amounts for the n-th line is the same as the sum of the exposure amounts for the first line. That is, the sum of the exposure amounts for all horizontal lines will be the same or close to the same. In other words, it is possible to generate an image (fluorescence image) with no unevenness in brightness, which is suitable for observation.

[0062]

[0063] Figures 8 to 10 illustrate light source control when the exposure time exp is long. A long exposure time exp means that the regions indicating effective exposure times overlap temporally between adjacent frames (fields) (the same applies hereafter). Figures 8(a), 9(a), and 10(b) correspond to Figure 6(a). Figures 8(b), 9(b), and 10(c) correspond to Figure 6(b). Figure 9(c) is an enlarged view of a portion of Figure 9(b). Figure 10(a) represents a calculation time set to 0 relative to real time, with the start of the frame being 0, for the purpose of simplifying the calculations in Figure 10. Figure 10(d) is an enlarged view of a portion of Figure 10(c).

[0064] Next, let's consider the case where the exposure time exp is long. Focusing on the region that shows the effective exposure time for each horizontal line, the emission pattern Light(t) shifts by the non-exposure period noexp with each advance of one frame (field) (Figure 9). That is, the emission pattern Light(t) shifts by (X-1)*noexp in any X frame (Figure 10). Here, (X-1)*noexp can be expressed as an integer multiple of the exposure time exp plus a fraction f. Also, the emission pattern Light(t) is an emission pattern with a period of exposure time exp. Therefore, the emission pattern that has been shifted by an integer multiple of the exposure time exp returns to the original emission pattern. As a result, the emission pattern Light(t) becomes an emission pattern that has been shifted by the fraction f. And although it has shifted by the fraction f in time, since the exposure period is the exposure time exp, the sum of the exposure amounts is the same as if it had not been shifted, as shown in Figure 10 and equation (5) below. That is, the sum of the exposure amounts for all horizontal lines is the same or approaches the same. In other words, it is possible to generate an image (fluorescence image) with uniform brightness, which is suitable for observation.

[0065]

[0066] In the above explanation, the light emission pattern Light(t) was assumed to be a light emission pattern in which the excitation light is constantly emitted while changing the amount of excitation light emitted over time (Figure 2(b)). However, any light emission pattern with a period equal to the exposure time exp can produce the same effect even if the excitation light is emitted intermittently (pulsed emission) (Figure 2(c)).

[0067] Figure 11 illustrates light source control (emission pattern Light(t): pulsed emission) when the exposure time exp is long. Figure 11(a) corresponds to Figure 5(a). In Figure 11(a), each pixel to be exposed is labeled with the number "1". Figure 11(b) shows the emission pattern Light(t). In Figure 11(b), the emission pattern Light(t) has a period of exposure time exp and is shown as two pulsed emission cycles within that exposure time exp. The emission amount of these pulsed emission cycles is set to "5". Figure 11(c) shows the exposed areas (areas with dots) for each horizontal line. Figure 11(d) shows the sum of the exposure amounts for receiving the observed fluorescence for each horizontal line.

[0068] First, let's explain light source control (light emission pattern Light(t): pulsed emission) when the exposure time exp is long. Even in this case, if the pulsed light emission pattern Light(t) has a period equal to the exposure time exp, the sum of the exposure amounts for all horizontal lines will be the same (in the case of Figure 11, the sum is "30") or close to it. In other words, it is possible to generate an image (fluorescence image) with no unevenness in brightness, which is suitable for observation.

[0069] Figure 12 illustrates light source control (light emission pattern Light(t): pulsed emission) when the exposure time exp is short. Figures 12(a) to 12(d) correspond to Figures 11(a) to 11(d), respectively.

[0070] Next, we will explain light source control (emission pattern Light(t): pulsed emission) when the exposure time exp is short. Even in this case, if the pulsed emission pattern Light(t) is an emission pattern with a period equal to the exposure time exp, the sum of the exposure amounts for all horizontal lines will be the same (in the case of Figure 12, the sum is "20") or close to it. In other words, it is possible to generate an image (fluorescence image) with no unevenness in brightness, which is suitable for observation.

[0071] Incidentally, when excitation light propagates through the first optical path P1 (Figure 1) and when return light propagates through the second optical path P2 (Figure 1), the excitation light and return light irradiate the members forming the observation optical path P0 (Figure 1) of the first and second optical paths P1 and P2 (hereinafter referred to as unwanted light generating members), causing autofluorescence (hereinafter referred to as unwanted light) to be generated from the unwanted light generating members. The first optical path P1 is an optical path that follows the route from the light source device 3 to the light guide 4 to the insertion section 2 to the observation target OB. The second optical path P2 is an optical path that follows the route from the observation target OB to the insertion section 2 to the first image sensor 531. Examples of the unwanted light generating members include components contained in multi-component glass such as lenses, material components contained in color filters, adhesives used to join lenses and other optical components together, and oil adhering to optical components such as lenses. Such unwanted light has a wavelength band that includes the wavelength band of the fluorescence being observed, which is the light being observed in fluorescence observation, and thus becomes noise during the fluorescence observation. Furthermore, such unwanted light can also be generated when the observation target OB is irradiated with excitation light.

[0072] Furthermore, if the fluorescence of the target object OB is weak, it is necessary to adjust the signal value based on the fluorescence of the target object captured by the first image sensor 531 in order to separate the fluorescence of the target object from the unwanted light mentioned above and perform good fluorescence observation. However, adjusting the signal value based on the fluorescence of the target object is difficult because it is affected by the following (1) to (4).

[0073] (1) Drugs Generally, the amount of light emitted from a drug that is the target of observation varies depending on the type and dosage of the drug. The type of drug administered to the target OB is selected according to the target OB (cancer, blood, lymph, etc.). Furthermore, in order to image the target of observation emitted from the drug in the medical observation system 1, a drug is selected in which the wavelength of the excitation light that excites the drug and the wavelength of the target of observation emitted from the drug can be separated. The drugs selected in this way each emit different amounts of light for the target of observation. In addition, the amount of light emitted for the target of observation can be adjusted by the dosage of the drug, but it is difficult to increase the dosage more than necessary in order to realize a minimally invasive procedure. In other words, it is difficult to adjust the amount of light emitted for the target of observation by selecting the type of drug and adjusting the dosage. As a result, it is difficult to adjust the signal value based on the target of observation captured by the first image sensor 531 by selecting the type of drug and adjusting the dosage.

[0074] (2) The amount of fluorescence light emitted from the observed OB varies depending on the location and condition of the observed OB. Specifically, in the case of an observed OB in a location or condition where the drug tends to accumulate, the amount of fluorescence light emitted from the observed OB increases. On the other hand, in the case of an observed OB in a location or condition where the drug flows easily and does not accumulate easily, the amount of fluorescence light emitted from the observed OB decreases, and the afterglow time also shortens. Furthermore, if the observed OB is a tumor, the amount of fluorescence light received by the first image sensor 531 changes depending on its extent, size, and depth. In other words, it is difficult to adjust the amount of fluorescence light emitted from the observed OB depending on the type and condition of the observed OB. As a result, it is difficult to adjust the signal value based on the fluorescence light captured by the first image sensor 531 depending on the type and condition of the observed OB.

[0075] (3) Light Source Device The amount of fluorescence observed varies depending on the amount of excitation light emitted from the light source device 3. Increasing the amount of excitation light may require adjusting the power supplied to the light source device 3. However, the amount of power that can be supplied to the light source device 3 is limited according to the upper limit of the power required to operate the entire medical observation system 1. Furthermore, the amount of excitation light must be adjusted considering factors such as heat generation in the components constituting the optical path of the excitation light (for example, heat generation between the light guide 4 and the insertion part 2), compatibility with the laser class, the amount of light energy received by the observation target OB and surrounding biological tissue (high light energy levels pose a risk of burns), or the rate of fading of the fluorescence observed from the drug. In addition, the amount of excitation light can also be adjusted by changing the number of excitation light sources mounted on the light source device 3. However, the number of light sources may affect the size of the light source device 3. The size of the light source device 3 may be limited by the size of the cart used to transport the light source device 3, etc. In other words, it is difficult to adjust the amount of fluorescence observed by adjusting the amount of excitation light. As a result, it is difficult to adjust the signal value based on the observed fluorescence image captured by the first image sensor 531 by adjusting the intensity of the excitation light.

[0076] (4) Depending on the amount of light from the target fluorescence received by the first image sensor 531, the signal value based on the target fluorescence generated from the first image sensor 531 will differ. To adjust the signal value based on the target fluorescence, it is desirable to select the first image sensor 531 which has the optimal sensitivity and configuration for imaging the target fluorescence. However, the first image sensor 531 may be required not only to output an image for fluorescence observation based on the reception of the target fluorescence in a predetermined wavelength band, but also to output an image for normal light observation based on the reception of visible light such as white light. Furthermore, the first image sensor 531 may be required to output an image for fluorescence observation that corresponds to a wide wavelength band or multiple wavelength bands within the wavelength band including visible and invisible light. In addition, even when using the same drug, the amount of light from the target fluorescence may change depending on the procedure or the target OB, and the first image sensor 531 may be required to output an image for fluorescence observation that corresponds to such changes in the amount of light from the target fluorescence. In that case, the first image sensor 531 must be selected to be an element capable of observing those elements, and it may not be possible to use an image sensor with characteristics optimal for imaging fluorescence in a predetermined wavelength band. Furthermore, although the first image sensor 531 is disposed within the camera head 5, there are size and weight requirements for the camera head 5 suitable for observation, which may limit the types of the first image sensor 531, including its size. Moreover, even when the first image sensor 531 is disposed not only within the camera head 5, but also at the tip of a rigid or flexible endoscope, there are size and weight requirements for observation, which may limit the types of the first image sensor 531, including its size. In other words, it is difficult to adjust the signal value based on the observed fluorescence imaged by the first image sensor 531 by selecting the type of first image sensor 531.

[0077] As described above, the signal value based on the observed fluorescence image captured by the first image sensor 531 is determined within the above constraints and therefore cannot be easily adjusted.

[0078] Furthermore, as shown in Figures 11 and 12, by employing a pulsed emission pattern Light(t), the amount of light (excitation light and return light) traveling along the observation optical path P0 is not increased unnecessarily, thus preventing an excessive amount of unwanted light from being generated. In other words, noise during fluorescence observation can be reduced. To put it another way, it is possible to generate imaging images (fluorescence images) suitable for observation.

[0079] As mentioned above, there are various types of drugs administered to the OB (observed tissue) to be observed, ranging from those that emit bright fluorescence to those that emit only faint fluorescence. Furthermore, there are various parts of the OB to be observed, from areas where the drug accumulates and emits bright fluorescence to areas where the concentration of the drug is low due to perfusion and metabolism of the OB, resulting in weak fluorescence. Therefore, users performing fluorescence observation require a function to adjust the brightness. This function is generally achieved by gain control, but when a high-sensitivity imager is used as the first image sensor 531, the image may become bright even without multiplying by the gain (analog gain and digital gain). In this case, a negative gain is multiplied in signal processing, but if the signal value based on the fluorescence of the observed tissue has saturated, there is a problem in that the gradation of the signal value cannot be restored.

[0080] Furthermore, as shown in Figures 11 and 12, by employing both electronic shutter control (exposure time adjustment) and a pulsed emission pattern Light(t), even in cases where the signal value based on the observed fluorescence saturates, such as when using a brightly fluorescent drug, the brightness of the captured image (fluorescence image) can be adjusted to an appropriate level without losing the gradation of the signal value.

[0081] Incidentally, when the medical control device according to this disclosure is combined with an open-field observation device used in abdominal surgery, and a pulsed light emission pattern Light(t) is adopted, the user will directly see the flashing of the first light (excitation light). For this reason, it is not desirable to make the period of the pulsed light emission in the pulsed light emission pattern Light(t) unnecessarily large. In this case, it is preferable to make the period of the pulsed light emission 1 / 120 [s] or less.

[0082] As described above, in this embodiment, the light source control unit 941 emits first light (excitation light) from the first light source 31 based on the exposure time of the first image sensor 531. Specifically, the light source control unit 941 emits first light from the first light source 31 in a light emission pattern with a period of exposure time. Furthermore, the light source control unit 941 emits first light from the first light source 31 so that the sum of the exposure amounts of first light for each exposure time of at least two or more horizontal lines on the first image sensor 531 approaches the sum of the exposure amounts of first light.

[0083] (Other Embodiments) Up to this point, embodiments for implementing the present disclosure have been described, but the present disclosure should not be limited to the embodiments described above. In the embodiments described above, the following modifications 1 to 4 may also be adopted.

[0084] (Modification 1) Figures 13 to 17 illustrate Modification 1 of the embodiment. Figure 13 corresponds to Figure 3. Figure 14 corresponds to Figure 6 and illustrates light source control when the exposure time exp is short. Figures 15 to 17 illustrate light source control when the exposure time exp is long. Specifically, Figures 15 and 16 correspond to Figure 8. Figure 17 shows the first synchronization signal Vsync1 generated by the first synchronization signal generation unit 55 and the second synchronization signal Vsync2 generated by the second synchronization signal generation unit 32, respectively. In the following, the first and second synchronization signals Vsync1 and Vsync2 may be collectively referred to as the synchronization signal Vsync.

[0085] In the embodiment described above, the light source control unit 941 and the imaging control unit 942 were provided in the control device 9, but this is not limited to this. For example, as shown in the modified example 1 in Figure 13, the light source control unit 941 may be provided in the light source device 3 and the imaging control unit 942 may be provided in the camera head 5.

[0086] The imaging control unit 942 in this modified example 1 executes the imaging control described in the above embodiment based on the exposure time calculated by the control unit 94 and the first synchronization signal Vsync1 generated by the first synchronization signal generation unit 55 provided on the camera head 5.

[0087] The light source control unit 941 in this modified example 1 performs the light source control described in the above embodiment based on the exposure time calculated by the control unit 94 and the second synchronization signal Vsync2 generated by the second synchronization signal generation unit 32 provided in the light source device 3. Furthermore, the light source control unit 941 in this modified example 1 performs the following light source control in the case of a short exposure time and in the case of a long exposure time, respectively.

[0088] First, let's explain the control of the light source when the exposure time is short. When the camera head 5 and the light source device 3 operate using different synchronization signals Vsync (first and second synchronization signals Vsync1 and Vsync2), a discrepancy may occur between the first and second synchronization signals Vsync1 and Vsync2 over time. When the exposure time is short, the light source control unit 941 resets the light emission pattern Light(t) in synchronization with the first synchronization signal Vsync1, as shown in Figure 14, for example, when the discrepancy between the first and second synchronization signals Vsync1 and Vsync2 exceeds a certain threshold. This reset means returning the light emission pattern to the first emission of the cycle of that light emission pattern. In this way, synchronization is applied to each first synchronization signal Vsync1, and the sum of the exposure amounts for all horizontal lines becomes the same or approaches the same.

[0089] Furthermore, if the exposure time is short, the light source control unit 941 may reset the light emission pattern Light(t) in synchronization with the first synchronization signal Vsync1, without comparing the difference between the first and second synchronization signals Vsync1 and Vsync2 with a specific threshold.

[0090] Next, we will explain the control of the light source when the exposure time is long. However, when the exposure time is long, there is the same problem as when the exposure time is short: resetting the light emission pattern Light(t) in synchronization with the first synchronization signal Vsync1. That is, as shown in Figure 15, the premise of repeated light emission at the period of the exposure time is broken for the horizontal line that has not finished exposure (the part enclosed by the ellipse in Figure 15), making it difficult to make the sum of the exposure amounts for all horizontal lines the same or close to it.

[0091] Therefore, in this modified example 1, the light source control unit 941 calculates, for example, the phase difference Δtv of the first and second synchronization signals Vsync1 and Vsync2 (Figure 17) when the exposure time is long. Then, when the phase difference Δtv of the first and second synchronization signals Vsync1 and Vsync2 exceeds a certain threshold, the light source control unit 941 adjusts the phase of the light emission pattern Light(t) based on the phase difference Δtv. Here, the light source control unit 941 adjusts the phase of the light emission pattern Light(t) at timing TI within the entire line exposure period, where the effect on the brightness unevenness of the captured image (fluorescent image) is minimal (Figure 16). As a result, the sum of the exposure amounts for all horizontal lines becomes the same or approaches the same.

[0092] (Modification 2) The medical observation system according to Modification 2 is a medical observation system that uses a so-called videoscope (flexible endoscope) with an image sensor mounted on the tip of the insertion part. For the sake of explanation, the medical observation system 1 according to Modification 2 will be referred to as medical observation system 1B below.

[0093] Figure 18 is a diagram illustrating a modified example of the embodiment. As shown in Figure 18, the medical observation system 1B includes an endoscope 300B that captures images of the internal body of the observation site by inserting an insertion part 2B into the body and outputs the captured images (fluorescence images), a light source device 3 that emits excitation light from the tip of the endoscope 300B, a control device 9 that processes the captured images output from the endoscope 300B, and a display device 7 that is connected to the control device 9 via a second transmission cable 8 and displays an image based on the video signal processed by the control device 9.

[0094] As shown in Figure 18, the endoscope 300B comprises an insertion section 2B having a flexible, elongated shape, an operating section 301 connected to the base end of the insertion section 2B and receiving various operations, and a universal cord 302 extending from the operating section 301 in a direction different from the direction in which the insertion section 2B extends, and containing various cables connected to the light source device 3 and the control device 9. As shown in Figure 18, the insertion section 2B comprises a tip section 24, a flexible bending section 25 connected to the base end of the tip section 24 and composed of a plurality of bending pieces, and a flexible, elongated flexible tube section 26 connected to the base end of the bending section 25.

[0095] The tip portion 24 incorporates a configuration substantially similar to that of the camera head 5 described in the above-described embodiment, although this is not shown in detail. The captured image captured by the tip portion 24 (first image sensor 531) is output to the control device 9 via the operation unit 301 and the universal code 302.

[0096] Even when adopting the configuration of the modified example 2 described above, the same effects as those of the embodiment described above are achieved.

[0097] (Modification 3) The medical observation system according to Modification 3 is a medical observation system that uses a surgical microscope to magnify and image a predetermined field of view of the inside (in vivo) or surface (biological surface) of the subject being observed. For the sake of explanation, the medical observation system 1 according to Modification 3 will be referred to as medical observation system 1C below.

[0098] Figure 19 illustrates a third modified example of the embodiment. As shown in Figure 19, the medical observation system 1C comprises a surgical microscope 12 that captures images for observing a subject and outputs captured images (fluorescence images), a control device 9 that processes the captured images output from the surgical microscope 12, and a display device 7 connected to the control device 9 via a second transmission cable 8 and displaying images based on the video signals processed by the control device 9.

[0099] As shown in Figure 19, the surgical microscope 12 comprises a microscope unit 121 that magnifies and images minute parts of a subject and outputs the captured image, a support unit 122 connected to the base end of the microscope unit 121 and including an arm that rotatably supports the microscope unit 121, and a base unit 123 that rotatably holds the base end of the support unit 122 and is movable on the floor. The control device 9 is installed on the base unit 123 as shown in Figure 13. Although not specifically shown in the illustration, a light source device 3 that emits excitation light from the surgical microscope 12 to the object being observed is also installed on the base unit 123. Note that the base unit 123 may be fixed to the ceiling or wall to support the support unit 122, rather than being movably installed on the floor.

[0100] Although not shown in detail in the illustration, the microscope unit 121 incorporates a configuration substantially similar to that of the camera head 5 described in the above-described embodiment. The image captured by the microscope unit 121 (first image sensor 531) is output to the control device 9 via the first transmission cable 6, which is wired along the support unit 122.

[0101] Even when adopting the configuration of the modified example 3 described above, the same effects as those of the embodiment described above are achieved.

[0102] (Modification 4) Figures 20 and 21 illustrate Modification 4 of the embodiment. Specifically, Figure 20 is a side view of the ring light 15. Figure 21 is a front view of the ring light 15 (left side in Figure 20). In this Modification 4, in addition to the insertion part 2 described in the above embodiment, the ring light 15 shown in Figures 20 and 21 is detachably connected to the camera head 5. That is, depending on the user's usage, the camera head 5 may be connected to either the insertion part 2 or the ring light 15, as shown in Figure 20.

[0103] Unlike the insertion unit 2, the ring light 15 is not inserted into the object of observation, but rather supplies excitation light to the surgical unit and captures the reflected light (subject image) from the surgical unit. As shown in Figures 20 and 21, the ring light 15 comprises an illumination unit 151 and a subject image capture unit 152 that captures the subject image.

[0104] As shown in Figures 20 and 21, the illumination unit 151 comprises a housing 1511 and a plurality of illumination lenses 1512. The housing 1511 has an annular shape centered on the optical axis Ax. The other end of the light guide 4 is detachably connected to the housing 1511.

[0105] As shown in Figure 21, the multiple illumination lenses 1512 are arranged at predetermined intervals along the circumferential direction centered on the optical axis Ax on the front end face of the housing 1511. The multiple illumination lenses 1512 each irradiate the surgical area with excitation light supplied from the light source device 3 and introduced into the housing 1511 via the light guide 4.

[0106] The subject image acquisition section 152 extends along the optical axis Ax. Within the subject image acquisition section 152, there is an optical system composed of one or more lenses that collects the reflected light (observed fluorescence) of the excitation light irradiated from multiple illumination lenses 1512 via the surgical section. Furthermore, a connection section 1521 is provided at the base end (right side in Figure 20) of the subject image acquisition section 152. This connection section 1521 is designed (shaped) to be compatible with the eyepiece section 21 in the insertion section 2 and is detachably connected to the camera head 5.

[0107] Even when adopting the configuration of the modified example 4 described above, the same effects as those of the embodiment described above are achieved.

[0108] The following configurations also fall within the technical scope of this disclosure: (1) A medical control device comprising a light source control unit that emits a first light from a light source device toward an object to be observed, and an imaging control unit that causes a second light, which is a return light from the object to be observed based on the first light, to be imaged by a rolling shutter type image sensor in which a plurality of pixels are arranged in a two-dimensional manner in units of horizontal lines, wherein the light source control unit determines the period of the emission pattern of the first light from the light source device based on the exposure time of the image sensor and emits the first light. (2) The medical control device according to (1) above, wherein the light source control unit emits the first light from the light source device in an emission pattern with a period of the exposure time. (3) The medical control device according to (2) above, wherein the emission pattern is an emission pattern in which the first light is emitted at all times and the amount of the first light changes over time. (4) The medical control device according to (2) above, wherein the emission pattern is an emission pattern in which the first light is emitted intermittently. (5) The medical control device according to (4), wherein the light emission pattern is a light emission pattern in which the first light is emitted with a period of 1 / 120 [second] or less. (6) A medical control device comprising a light source control unit that emits a first light from a light source device toward an object to be observed, and an imaging control unit that causes a rolling shutter type image sensor, in which a plurality of pixels are arranged in a two-dimensional manner in units of horizontal lines, to image a second light which is the reflected light from the object to be observed based on the first light, wherein the light source control unit emits the first light from the light source device such that the sum of the exposure amounts of the first light at exposure times for at least two or more horizontal lines on the image sensor approaches each other. (7) A medical observation system comprising: a light source device that emits a first light; a light source control unit that emits the first light from the light source device toward an object to be observed; a rolling shutter type image sensor in which a plurality of pixels are arranged in two dimensions in units of horizontal lines, and an imaging control unit that causes the image sensor to image the second light, which is the reflected light from the object to be observed based on the first light, wherein the light source control unit determines the period of the emission pattern of the first light from the light source device based on the exposure time of the image sensor and emits the first light.(8) The medical observation system according to (7), wherein the light source control unit emits the first light from the light source device in a light emission pattern with a period of exposure time. (9) The medical observation system according to (8), further comprising a synchronization signal generation unit that generates a synchronization signal, wherein the light source control unit and the imaging control unit control the operation of the light source device and the image sensor in synchronization with the synchronization signal, and the light source control unit resets the light emission pattern in synchronization with the synchronization signal. (10) The medical observation system according to (8), comprising a first synchronization signal generation unit that generates a first synchronization signal for controlling the operation of the image sensor, and a second synchronization signal generation unit that generates a second synchronization signal for controlling the operation of the light source device, wherein the light source control unit adjusts the phase of the light emission pattern based on the phase difference between the first synchronization signal and the second synchronization signal. (11) The medical observation system according to (10), wherein the light source control unit adjusts the phase of the light emission pattern at timings within the entire line exposure period of the image sensor. (12) The medical observation system according to any one of (7) to (11), wherein the first light is broadband light or narrowband light. (13) The medical observation system according to any one of (7) to (12), wherein the light source device includes a first light source that emits excitation light which is the first light, and the first light source is comprised of one or more. (14) The medical observation system according to any one of (7) to (13), wherein the light source device includes a first light source that emits excitation light which is the first light, and the first light source is comprised of an LED or a semiconductor laser. (15) The medical observation system according to (13) or (14), wherein the excitation light is narrowband light. (16) The medical observation system according to any one of (7) to (12), wherein the light source device includes a first light source that emits light including a visible wavelength band which is the first light, and the first light source is comprised of one or more. (17) The medical observation system according to any one of (7) to (12), (16), wherein the light source device includes a first light source that emits light including a visible wavelength band which is the first light, and the first light source is composed of an LED or a semiconductor laser.

[0109] 1, 1B, 1C Medical observation system 2, 2B Insertion section 3 Light source device 4 Light guide 5 Camera head 6 First transmission cable 7 Display device 8 Second transmission cable 9 Control device 10 Third transmission cable 12 Surgical microscope 15 Ring light 21 Eyepiece section 22 Excitation light cut filter 24 Tip section 25 Bending section 26 Flexible tube section 31 First light source 32 Second synchronization signal generation section 51 Lens unit 53 Imaging section 54 Communication section 55 First synchronization signal generation section 91 Communication section 92 Image memory 93 Processing module 94 Control section 95 Input section 96 Output section 97 Storage section 121 Microscope section 122 Support section 123 Base section 151 Illumination section 152 Subject image acquisition section 300B Endoscope 301 Operation Unit 302 Universal Code 531 First Image Sensor 533 Signal Processing Unit 931 Memory Controller 932 Image Processing Unit 933 Display Control Unit 941 Light Source Control Unit 942 Imaging Control Unit 1511 Housing 1512 Illumination Lens 1521 Connection Unit Ax Optical Axis CN1, CN2 Connectors OB Object to Observe P0 Observation Optical Path P1 First Optical Path P2 Second Optical Path TI Timing

Claims

1. A medical control device comprising: a light source control unit that emits a first light from a light source device toward an object to be observed; and an imaging control unit that causes a second light, which is the reflected light from the object to be observed based on the first light, to be imaged by a rolling shutter type image sensor in which a plurality of pixels are arranged in a two-dimensional manner in units of horizontal lines, wherein the light source control unit determines the period of the emission pattern of the first light from the light source device based on the exposure time of the image sensor and emits the first light.

2. The medical control device according to claim 1, wherein the light source control unit emits the first light from the light source device in a light emission pattern with a period of exposure time.

3. The medical control device according to claim 2, wherein the light emission pattern is a light emission pattern in which the first light is constantly emitted and the amount of the first light changes over time.

4. The medical control device according to claim 2, wherein the light emission pattern is a light emission pattern in which the first light is emitted intermittently.

5. The medical control device according to claim 4, wherein the light emission pattern is a light emission pattern in which the first light is emitted with a period of 1 / 120 [second] or less.

6. A medical control device comprising: a light source control unit that emits a first light from a light source device toward an object to be observed; and an imaging control unit that causes a second light, which is the reflected light from the object to be observed based on the first light, to be imaged by a rolling shutter type image sensor in which a plurality of pixels are arranged in a two-dimensional manner in units of horizontal lines, wherein the light source control unit emits the first light from the light source device such that the sum of the exposure amounts of the first light at exposure times for at least two or more horizontal lines on the image sensor approaches each other.

7. A medical observation system comprising: a light source device that emits a first light; a light source control unit that emits the first light from the light source device toward an object to be observed; a rolling shutter type image sensor in which a plurality of pixels are arranged in two dimensions in units of horizontal lines, and an imaging control unit that causes the image sensor to image the second light, which is the reflected light from the object to be observed based on the first light, wherein the light source control unit determines the period of the emission pattern of the first light from the light source device based on the exposure time of the image sensor and emits the first light.

8. The medical observation system according to claim 7, wherein the light source control unit emits the first light from the light source device in a light emission pattern with a period of the exposure time.

9. The medical observation system according to claim 8, further comprising a synchronization signal generation unit for generating a synchronization signal, wherein the light source control unit and the imaging control unit control the operation of the light source device and the image sensor in synchronization with the synchronization signal, and the light source control unit resets the light emission pattern in synchronization with the synchronization signal.

10. A medical observation system according to claim 8, comprising: a first synchronization signal generation unit for generating a first synchronization signal for controlling the operation of the image sensor; and a second synchronization signal generation unit for generating a second synchronization signal for controlling the operation of the light source device, wherein the light source control unit adjusts the phase of the light emission pattern based on the phase difference between the first synchronization signal and the second synchronization signal.

11. The medical observation system according to claim 10, wherein the light source control unit adjusts the phase of the light emission pattern at timings within the entire line exposure period of the image sensor.

12. The medical observation system according to claim 7, wherein the first light is broadband light or narrowband light.

13. The medical observation system according to claim 7, wherein the light source device includes a first light source that emits excitation light which is the first light, and the first light source is comprised of one or more.

14. The medical observation system according to claim 7, wherein the light source device includes a first light source that emits excitation light which is the first light, and the first light source is composed of an LED or a semiconductor laser.

15. The medical observation system according to claim 13, wherein the excitation light is narrowband light.

16. The medical observation system according to claim 7, wherein the light source device includes a first light source that emits light including a visible wavelength band, and the first light source is comprised of one or more.

17. The medical observation system according to claim 7, wherein the light source device includes a first light source that emits light including a visible wavelength band, the first light source being an LED or a semiconductor laser.

Images