JP2017209530A - Light source device for endoscopes and endoscope system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light source device for endoscopes and an endoscope system that can reduce light intensity in a wavelength band of 460 nm or more and 500 nm or less without enlarging the device structure.SOLUTION: A V-LD 53 emits excitation light LE. A rotation phosphor 50, one of phosphors, emits green light and red light as fluorescence when irradiated with excitation light LED. A V-LED 56c emits violet light LV. A fourth DM 55d integrates an optical path of fluorescence with an optical path of violet light LV.SELECTED DRAWING: Figure 16

Description

  The present invention relates to an endoscope light source device and an endoscope system having an excitation light source and a phosphor.

  In recent medical treatments, diagnosis using an endoscope system including an endoscope light source device, an electronic endoscope (hereinafter simply referred to as an endoscope), and a processor device is widely performed. The endoscope light source device generates illumination light and irradiates the sample. An endoscope images an inside of a specimen irradiated with illumination light with an image sensor and generates an imaging signal. The processor device performs image processing on the imaging signal generated by the endoscope, and generates an observation image to be displayed on the monitor.

  Conventionally, in an endoscope light source device, a lamp light source such as a xenon lamp or a halogen lamp that emits white light as illumination light has been used, but recently, a light of a specific color is emitted instead of the lamp light source. Semiconductor light sources such as laser diodes (LDs) and light emitting diodes (LEDs) are being used.

  In order to increase the brightness of illumination light, an excitation light source (blue LD) that emits excitation light (blue light) and a phosphor that emits fluorescence (green light) when irradiated with excitation light are provided. An endoscope light source device that supplies fluorescence emitted from a phosphor to an endoscope is known (see Patent Document 1). Patent Document 1 includes a “reflection type” in which fluorescence is emitted from a phosphor in a direction opposite to the incident direction of excitation light, and a “transmission type” in which fluorescence is emitted from a phosphor in the incident direction of excitation light. Have been described.

  In the reflection type, a dichroic mirror that reflects excitation light and transmits fluorescence is disposed at an angle of 45 ° on the optical path of the excitation light. The excitation light emitted from the excitation light source is reflected by the dichroic mirror and applied to the phosphor, and the fluorescence emitted from the phosphor toward the dichroic mirror passes through the dichroic mirror and is emitted toward the endoscope. The

  On the other hand, in the transmissive type, a dichroic mirror that transmits excitation light and reflects fluorescence is disposed between the excitation light source and the phosphor. Excitation light emitted from the excitation light source passes through the dichroic mirror and irradiates the phosphor, and fluorescence emitted from the phosphor in the direction opposite to the dichroic mirror is emitted toward the endoscope. The dichroic mirror is intended to increase the light emission efficiency by reflecting the fluorescence from the phosphor toward the excitation light source and returning it to the phosphor.

  In addition, in the endoscope light source device described in Patent Document 1, in order to generate blue light, red light, and violet light in addition to fluorescence (green light), a blue light source, a red light source configured by LEDs, A purple light source is provided. One dichroic mirror is provided for each light source in order to integrate the optical paths of these lights with the optical path of the fluorescent light (green light) from the phosphor.

  Of these lights, violet light is light that is easily absorbed by hemoglobin on the surface layer of the living tissue and is reflected almost without diffusing into the living tissue around the blood vessel. Green light is light that diffuses deeper into the living tissue than violet light, and is more absorbed by hemoglobin. For this reason, in the blood vessel enhancement observation mode for emphasizing the blood vessels on the surface of the living tissue, only purple light and green light are used as illumination light.

  However, the blood vessel-enhanced observation image obtained using only purple light and green light as illumination light is a pseudo-color image that is darker than normal observation images using white light and has low color reproducibility. It is known that white light is used and an image with high blood vessel contrast is obtained by reducing the light intensity in the wavelength band of 460 nm to 500 nm from the white light (see Patent Document 2). This is because light in the wavelength band of 460 nm to 500 nm is hardly absorbed by hemoglobin and is likely to be reflected or scattered.

JP 2013-215435 A Japanese Patent No. 5306447

  Of the reflective and transmissive endoscope light source devices described in Patent Document 1, the transmissive type has the advantage that the device configuration can be reduced in size. This is because in the reflection type, the dichroic mirror needs to be inclined by 45 ° with respect to the optical path of the excitation light in order to bend the optical path of the excitation light, but in the transmission type, it is not necessary to incline the dichroic mirror. It is.

  In this transmissive endoscope light source device, each light source emits light to generate white light, and from this white light, the light intensity in the wavelength band of 460 nm to 500 nm is reduced as described in Patent Document 2. Thus, it is conceivable to obtain an image with high blood vessel contrast.

  However, in order to reduce the light intensity in the wavelength band of 460 nm to 500 nm from white light, it is necessary to provide a notch filter having a low light transmittance for light in the wavelength band of 460 nm to 500 nm. If the notch filter is simply provided, there is a problem in that the apparatus configuration is enlarged although the transmission structure is adopted to reduce the apparatus configuration.

  The present invention makes it possible to reduce the light intensity in the wavelength band of 460 nm or more and 500 nm or less without enlarging the apparatus configuration in an endoscope light source device and endoscope system having a transmissive phosphor. It is an object to provide an endoscope light source device and an endoscope system.

  In order to achieve the above object, an endoscope light source device of the present invention is an excitation light source that emits excitation light and a phosphor that emits fluorescence when irradiated with the excitation light. A phosphor that emits light, a first light source that emits specific light having a wavelength band different from that of fluorescence, and a second dichroic mirror that integrates the optical path of the fluorescence and the optical path of the specific light.

  The second dichroic mirror preferably integrates the optical path of the fluorescence and the optical path of the specific light without integrating the optical path of the fluorescence and the optical path of the excitation light. The specific light is preferably violet light. The second dichroic mirror preferably has a characteristic of reducing the light intensity in the wavelength band of 460 nm to 500 nm. The second dichroic mirror preferably further has a characteristic of reducing the amount of light in a wavelength band of 560 nm or more and 590 nm or less.

  The phosphor preferably has a phosphor layer in which a phosphor material emitting green light and a phosphor material emitting red light are dispersed in a binder. The phosphor is preferably fixed. It is preferable to provide a first dichroic mirror that is disposed between the excitation light source and the phosphor, transmits the excitation light, and reflects a component of the fluorescence toward the excitation light source.

  The endoscope system of the present invention is an excitation light source that emits excitation light, a phosphor that emits fluorescence when irradiated with the excitation light, a phosphor that emits green light and red light as fluorescence, and fluorescence. A light source device comprising: a first light source that emits specific light having a different wavelength band; and a second dichroic mirror that is arranged on the optical path of the fluorescence and integrates the optical path of the fluorescence and the optical path of the specific light; An endoscope having an image sensor that images reflected light from the irradiated observation site, and a control unit that controls the light source device and the image sensor.

  According to the present invention, the second dichroic mirror that integrates the optical path of fluorescence and the optical path of violet light has the characteristic of reducing the light intensity in the wavelength band of 460 nm or more and 500 nm or less. Without doing so, the light intensity in the wavelength band of 460 nm or more and 500 nm or less can be reduced.

It is an external view of an endoscope system. It is a front view of the front-end | tip part of an endoscope. It is a block diagram which shows the electric constitution of an endoscope system. It is a figure which shows the structure of a color filter array. It is a figure which shows the structure of a light source part. It is a figure which shows the structure of a rotation fluorescent substance. It is a graph which shows the wavelength spectrum of illumination light. It is a graph which shows the optical characteristic of 1st DM. It is a graph which shows the optical characteristic of 2nd DM. It is a graph which shows the optical characteristic of 3rd DM. It is a graph which shows the optical characteristic of 4th DM. It is a graph which shows the optical characteristic of 3rd DM incorporating the notch characteristic. It is a graph which shows the optical characteristic of 4th DM which reversed the relationship of reflection and transmission. It is a graph which shows the optical characteristic of 4th DM incorporating the 2nd notch characteristic. It is a figure which shows the structure of the rotation fluorescent substance of 2nd Embodiment. It is a figure which shows the structure of the light source part of 2nd Embodiment. It is a timing diagram explaining the drive timing of the light source part of 2nd Embodiment, and an image sensor. It is a timing diagram explaining the generation timing of image data. It is a figure which shows the structure of the rotation fluorescent substance of 4th Embodiment. It is a figure which shows the structure of the light source part of 4th Embodiment. It is a figure which shows the structure of the rotation fluorescent substance of 5th Embodiment.

[First Embodiment]
In FIG. 1, an endoscope system 10 includes an electronic endoscope (hereinafter simply referred to as an endoscope) 11 that images an observation site in a living body as a specimen, and an observation site based on an imaging signal obtained by imaging. A processor device 12 that generates a display image, an endoscope light source device (hereinafter simply referred to as a light source device) 13 that supplies illumination light for irradiating an observation site to the endoscope 11, and a monitor 14 that displays the display image It has. An operation input unit 15 such as a keyboard or a mouse is connected to the processor device 12.

  The endoscope 11 connects the insertion unit 16 inserted into the digestive tract of a living body, the operation unit 17 provided at the proximal end portion of the insertion unit 16, and the endoscope 11 to the processor device 12 and the light source device 13. And a universal cord 18 for the purpose. The insertion portion 16 includes a distal end portion 19, a bending portion 20, and a flexible tube portion 21, and is connected in this order from the distal end side.

  As shown in FIG. 2, an illumination window 22 that irradiates the observation site with illumination light, an observation window 23 for capturing an image of the observation site, and an observation window 23 are washed on the distal end surface of the distal end portion 19. An air supply / water supply nozzle 24 for supplying air and water and a forceps outlet 25 for performing various treatments by projecting a treatment tool such as a forceps or an electric knife are provided. An imaging element 33 (see FIG. 3) is built in the back of the observation window 23.

  The bending portion 20 is composed of a plurality of connected bending pieces, and bends in the vertical and horizontal directions according to the operation of the angle knob 26 of the operation portion 17. By curving the bending portion 20, the distal end portion 19 is directed in a desired direction. The flexible tube portion 21 has flexibility and can be inserted into a tortuous tube passage such as an esophagus or an intestine. The insertion unit 16 guides the drive signal for driving the image sensor 33, the signal cable for transmitting the image signal output from the image sensor 33, and the illumination light supplied from the light source device 13 to the illumination window 22. A light guide 32 (see FIG. 3) is inserted.

  In addition to the angle knob 26, the operation unit 17 includes a forceps port 27 for inserting a treatment instrument, an air / water supply button 28 that is operated when air / water is supplied from the air / water supply nozzle 24, a still image. A freeze button (not shown) or the like is provided for photographing the image.

  A communication cable and a light guide 32 extending from the insertion portion 16 are inserted into the universal cord 18, and a connector 29 is attached to one end of the processor device 12 and the light source device 13. The connector 29 is a composite type connector composed of a communication connector 29a and a light source connector 29b. The communication connector 29a and the light source connector 29b are detachably connected to the processor device 12 and the light source device 13, respectively. One end of a communication cable is disposed on the communication connector 29a. An incident end 32a (see FIG. 3) of the light guide 32 is disposed on the light source connector 29b.

  In FIG. 3, the light source device 13 includes a light source unit 30 and a light source control unit 31. The light source unit 30 outputs illumination light based on the control of the light source control unit 31. The illumination light output from the light source unit 30 enters the incident end 32 a of the light guide 32 of the endoscope 11.

  The endoscope 11 includes a light guide 32, an imaging device 33, an imaging drive unit 34, an analog processing circuit (AFE: Analog Front End) 35, an irradiation lens 36, and an objective optical system 37. . The light guide 32 is a fiber bundle obtained by bundling a plurality of optical fibers. When the light source connector 29 b is connected to the light source device 13, the incident end 32 a of the light guide 32 disposed on the light source connector 29 b faces the emission end of the light source unit 30. The exit end of the light guide 32 located at the distal end portion 19 branches into two at the front stage of the illumination window 22 so that light is guided to the two illumination windows 22 respectively.

  An irradiation lens 36 is disposed in the back of the illumination window 22. The illumination light supplied from the light source device 13 is guided to the irradiation lens 36 by the light guide 32 and irradiated from the illumination window 22 toward the observation site. The irradiation lens 36 is a concave lens, and irradiates the illumination light emitted from the light guide 32 to a wide range of the observation site.

  An imaging element 33 is disposed behind the observation window 23 via an objective optical system 37. The image (reflected light) of the observation site is incident on the objective optical system 37 through the observation window 23, and is formed on the imaging surface 33 a of the image sensor 33 by the objective optical system 37.

  The imaging device 33 is a single-plate color CCD (Charge Coupled Device) image sensor or a CMOS (Complementary Metal Oxide Semiconductor) image sensor, and a plurality of pixels that generate pixel signals by photoelectric conversion are formed on the imaging surface 33a. Yes. A color filter array 38 shown in FIG. 4 is provided on the imaging surface 33a. The color filter array 38 includes a red (R) filter 38a, a green (G) filter 38b, and a blue (B) filter 38c. Each filter 38a, 38b, 38c is disposed on the light incident side corresponding to one pixel. The color array of the color filter array 38 is called a Bayer array. Further, microlenses (not shown) are provided on the color filter array 38 corresponding to the respective pixels.

  The pixel in which the R filter 38a is disposed receives red light LR described later. The pixel in which the G filter 38b is disposed receives green light LG described later. The pixel in which the B filter 38c is disposed receives blue light LB and violet light LV, which will be described later.

  The image pickup device 33 is driven by the image pickup drive unit 34, picks up an image formed on the image pickup surface 33a with a plurality of pixels via the color filter array 38, and outputs an image pickup signal. The imaging signal includes one of R, G, and B color signals (R signal, G signal, and B signal) for each pixel.

  The AFE 35 includes a correlated double sampling (CDS) circuit, an automatic gain control (AGC) circuit, an analog / digital (A / D) converter, and the like. The CDS circuit performs correlated double sampling processing on the imaging signal input from the imaging element 33 to remove noise. The AGC circuit amplifies the imaging signal from which noise has been removed by the CDS circuit. The A / D converter converts the imaging signal amplified by the AGC circuit into a digital signal having a predetermined number of bits and inputs the digital signal to the processor device 12.

  The processor device 12 includes a controller 40 as a control unit, a DSP (Digital Signal Processor) 41, a frame memory 42, an image processing unit 43, and a display control unit 44. The controller 40 has a CPU (Central Processing Unit), a ROM (Read Only Memory) that stores control programs and setting data necessary for control, a RAM (Random Access Memory) as a working memory for loading the control programs, and the like. The CPU executes the control program to control each unit of the processor device 12, the light source control unit 31, and the imaging drive unit 34.

  The DSP 41 performs signal processing such as pixel interpolation processing, gamma correction, and white balance correction on the imaging signal input from the AFE 35 via the communication connector 29a. In the pixel interpolation processing, pixel interpolation processing is performed for each of the R signal, the G signal, and the B signal. The DSP 41 causes the frame memory 42 to store the imaged signal subjected to signal processing as image data for each frame period.

  The image processing unit 43 reads the image data from the frame memory 42 and performs predetermined image processing to generate an observation image. The display control unit 44 converts the image generated by the image processing unit 43 into a video signal such as a composite signal or a component signal and outputs the video signal to the monitor 14.

  In FIG. 5, the light source unit 30 includes a rotating phosphor 50, a rotating motor 51, a motor driving unit 52, a violet laser diode (V-LD) 53, an LD driving unit 54, and first to fourth dichroic mirrors. (DM) 55a to 55d, blue LED (B-LED) 56a, red LED (R-LED) 56b, purple LED (V-LED) 56c, LED drive unit 57, and first to fifth collimators Lenses 58a to 58e and a condenser lens 59 are provided.

  The rotating phosphor 50 includes a disk-shaped wheel plate 60 and a phosphor layer 61 provided on one surface of the wheel plate 60. The wheel plate 60 is made of a transparent material such as glass.

As shown in FIG. 6, the phosphor layer 61 is embedded in a recess 62 formed on one surface of the wheel plate 60. The recess 62 is formed in a circumferential shape centering on the rotation shaft 63 of the wheel plate 60. In the phosphor layer 61, for example, β-SiAlON (β-Si _6-x Al _x O _x N _8-x ) is dispersed as a phosphor material, and excitation emitted from the V-LD 53 as an excitation light source. In response to light LE, green light LG is emitted. As shown in FIG. 7, the green light LG has a wavelength band of about 480 nm to 600 nm and a peak wavelength of about 540 nm.

  The LD drive unit 54 generates an LD drive signal (drive current or drive voltage) for driving the V-LD 53 based on the control of the light source control unit 31 and supplies the LD drive signal to the V-LD 53. The V-LD 53 has a plurality of LD elements (not shown) arranged in a two-dimensional array. As shown in FIG. 7, the V-LD 53 emits violet laser light having a peak wavelength of about 405 nm as excitation light LE.

  The first DM 55a is disposed on the optical path of the excitation light LE emitted from the V-LD 53 and perpendicular to the optical path of the excitation light LE. As shown in FIG. 8, the first DM 55a has a threshold λ1 at about 425 nm, reflects light having a wavelength equal to or greater than the threshold λ1, and transmits light having a wavelength smaller than the threshold λ1. That is, the first DM 55a transmits the excitation light LE. The rotating phosphor 50 is disposed so that the phosphor layer 61 is positioned on the optical path of the excitation light LE that has passed through the first DM 55a.

  The rotation motor 51 rotates the wheel plate 60 around the rotation shaft 63. The motor drive unit 52 generates a rotation drive signal based on the control of the light source control unit 31 and supplies the rotation drive signal to the rotation motor 51. The rotation motor 51 rotates the wheel plate 60 according to the rotation drive signal. The excitation light LE is continuously applied to a part of the phosphor layer 61 in a state where the wheel plate 60 is rotationally driven. Therefore, the irradiation position 64 of the excitation light LE on the phosphor layer 61 moves with the rotation of the wheel plate 60, and green light LG is generated from the irradiation position 64. The green light LG generated in the phosphor layer 61 travels forward and backward due to scattering.

  The first collimator lens 58a is a plano-convex lens or meniscus lens having a convex surface facing the V-LD 53 side, and is disposed between the first DM 55a and the rotating phosphor 50. The first collimator lens 58a collimates the green light LG toward the rear (V-LD 53 side) in the phosphor layer 61 and emits it toward the first DM 55a. The first DM 55a reflects the green light LG due to the optical characteristics described above. The first DM 55 a condenses the green light LG reflected and returned by the first DM 55 a on the phosphor layer 61 of the rotating phosphor 50.

  The second collimator lens 58b is a plano-convex lens or a meniscus lens having a convex surface facing the side opposite to the V-LD 53, and is disposed on the opposite side of the rotating phosphor 50 from the V-LD 53. The second collimator lens 58b collimates the green light LG incident from the rotating phosphor 50 and emits it along the optical path of the excitation light LE.

  As shown in FIG. 7, the B-LED 56a emits blue light LB having a wavelength band of about 430 nm to 480 nm and a peak wavelength of about 460 nm. The R-LED 56b emits red light LR having a wavelength band of about 580 nm to 640 nm and a peak wavelength of about 620 nm. The V-LED 56c emits purple light LV having a wavelength band of about 395 nm to 415 nm and a peak wavelength of about 405 nm.

  The blue light LB and the violet light LV are light that is largely absorbed by hemoglobin on the surface of the living tissue and is reflected without being diffused into the living tissue around the blood vessel. The green light LG is light that diffuses deeper in the living tissue than the blue light LB and the purple light LV, and is also more absorbed by hemoglobin.

  The LED driving unit 57 generates an LED driving signal (driving current or driving voltage) for driving each of the B-LED 56a, the R-LED 56b, and the V-LED 56c based on the control of the light source control unit 31, and each LED 56a. To 56c.

  The third collimator lens 58c is disposed on the optical path of the blue light LB emitted from the B-LED 56a, and emits the blue light LB in parallel. The optical path of the green light LG emitted from the second collimator lens 58b and the optical path of the blue light LB emitted from the third collimator lens 58c are orthogonal to each other, and the second DM 55b is disposed at this intersection. The green light LG is incident on one surface of the second DM 55b at an angle of 45 °, and the blue light LB is incident on the other surface at an angle of 45 °.

  As shown in FIG. 9, the second DM 55b has a threshold λ2 at about 490 nm, transmits light having a wavelength equal to or greater than the threshold λ2, and reflects light having a wavelength smaller than the threshold λ2. That is, the second DM 55b transmits the green light LG incident from the second collimator lens 58b and reflects the blue light LB incident from the third collimator lens 58c to bend the optical path by 90 °. Thereby, the optical path of the green light LG and the optical path of the blue light LB are integrated. Further, the second DM 55b reflects the excitation light LE incident from the second collimator lens 58b, and excludes the excitation light LE from the optical paths of the green light LG and the blue light LB. This is because the excitation light LE is a high-intensity laser light, and if the illumination light contains a laser light, the living tissue irradiated with the illumination light may be damaged.

  The fourth collimator lens 58d is arranged on the optical path of the red light LR emitted from the R-LED 56b, and emits the red light LR in parallel. The optical paths of the green light LG and blue light LB emitted from the second DM 55b and the optical path of the red light LR emitted from the fourth collimator lens 58d are orthogonal to each other, and the third DM 55c is disposed at this intersection.

  As shown in FIG. 10, the third DM 55c has a threshold λ3 at about 590 nm, reflects light having a wavelength equal to or greater than the threshold λ3, and transmits light having a wavelength smaller than the threshold λ3. That is, the third DM 55c transmits the green light LG and the blue light LB incident from the second DM 55b, reflects the red light LR incident from the fourth collimator lens 58d, and bends the optical path by 90 °. Thereby, the optical path of the green light LG and the blue light LB and the optical path of the red light LR are integrated.

  The fifth collimator lens 58e is disposed on the optical path of the purple light LV emitted from the V-LED 56c, and emits the purple light LV in parallel. The optical paths of the green light LG, blue light LB, and red light LR emitted from the third DM 55c are orthogonal to the optical path of the purple light LV emitted from the fifth collimator lens 58e, and the fourth DM 55d is disposed at this intersection. Has been.

  As shown in FIG. 11, the fourth DM 55d has a threshold λ4 at about 425 nm, transmits light having a wavelength equal to or greater than the threshold λ4, and reflects light having a wavelength smaller than the threshold λ4. The fourth DM 55d has a notch characteristic that reduces the light intensity in the wavelength band of 460 nm to 500 nm (460 nm to 500 nm). Specifically, in the characteristics of the wavelength band larger than the threshold λ4 of the fourth DM 55d, the light transmittance with respect to the wavelength band of 460 nm to 500 nm is α (for example, α = 30%), and the other light transmittance is almost 100. %.

  That is, the fourth DM 55d transmits the green light LG, the blue light LB, and the red light LR incident from the third DM 55c, reduces the light intensity in the wavelength band of 460 nm to 500 nm, and enters the purple light incident from the fifth collimator lens 58e. The light path is reflected to bend the optical path by 90 °. Thereby, the optical path of the green light LG, the blue light LB, and the red light LR and the optical path of the purple light LV are integrated.

  The condensing lens 59 is disposed on the optical path of the green light LG, the blue light LB, the red light LR, and the violet light LV emitted from the fourth DM 55d, and condenses these lights. The condensing lens 59 is disposed in the vicinity of the light source connector 29 b and causes the collected light to enter the incident end 32 a of the light guide 32.

  Next, the operation of the endoscope system 10 will be described. When performing an endoscopic diagnosis, the endoscope 11 is connected to the processor device 12 and the light source device 13, and the processor device 12 and the light source device 13 are powered on. Then, the insertion portion 16 of the endoscope 11 is inserted into the subject's digestive tract, and observation in the digestive tract is started. An instruction to start observation is given by the operation input unit 15.

  When the observation is started, the wheel plate 60 of the rotating phosphor 50 is rotated, and the V-LD 53 is driven to emit the excitation light LE. This excitation light LE passes through the first DM 55a, passes through the first collimator lens 58a, and is irradiated on the phosphor layer 61 of the rotating phosphor 50. The phosphor layer 61 emits green light LG with irradiation of the excitation light LE.

  Of the green light LG, the component toward the V-LD 53 side is collimated by the first collimator lens 58a, travels to the first DM 55a, is reflected by the first DM 55a, and enters the first collimator lens 58a again. The green light LG is collected by the first collimator lens 58a, returns to the phosphor layer 61, and is emitted toward the second collimator lens 58b. On the other hand, of the green light LG generated in the phosphor layer 61, the component going to the side opposite to the V-LD 53 is incident on the second collimator lens 58b as it is.

  The green light LG that has entered the second collimator lens 58b is collimated and emitted, passes through the second to fourth DMs 55b to 55d, and enters the condenser lens 59. When the green light LG passes through the fourth DM 55d, the light intensity in the wavelength band of 460 nm to 500 nm is reduced due to the notch characteristics of the fourth DM 55d. Further, in the excitation light LE, the component that did not contribute to the generation of the green light LG in the phosphor layer 61 passes through the second collimator lens 58b, but the component of the excitation light LE is reflected by the second DM 55b, It is excluded from the optical path of the green light LG and does not enter the condenser lens 59.

  Further, during the generation of the green light LG, the B-LED 56a, the R-LED 56b, and the V-LED 56c are driven, and the blue light LB, the red light LR, and the purple light LV are emitted. The blue light LB is collimated by the third collimator lens 58c, reflected by the second DM 55b, combined with the green light LG, passes through the third and fourth DM 55c and 55d, and enters the condenser lens 59. . When the blue light LB passes through the fourth DM 55d, the light intensity in the wavelength band of 460 nm to 500 nm is reduced due to the notch characteristics of the fourth DM 55d. That is, the second DM 55b integrates the optical path of the green light LG and the optical path of the blue light LB without integrating the optical path of the green light LG and the optical path of the excitation light LE.

  The red light LR is collimated by the fourth collimator lens 58d, then reflected by the third DM 55c, combined with the green light LG and the blue light LB, passes through the fourth DM 55d, and enters the condenser lens 59. The violet light LV is collimated by the fifth collimator lens 58e, then reflected by the fourth DM 55d, combined with the green light LG, the blue light LB, and the red light LR, and enters the condenser lens 59.

  Each light incident on the condensing lens 59 is condensed on the incident end 32a of the light guide 32 and supplied to the light guide 32 as illumination light (white light).

  In the endoscope 11, illumination light is guided to the illumination window 22 through the light guide 32 and is irradiated from the illumination window 22 to the observation site. The reflected light from the observation site enters the image sensor 33 from the observation window 23 via the objective optical system 37. The image sensor 33 images incident light (photoelectric conversion) for each frame period to generate an image signal. Each of the imaging signals is subjected to processing such as CDS, AGC, A / D conversion and the like by the AFE 35, and is input to the DSP 41 of the processor device 12 as a digital signal.

  In the DSP 41, signal processing such as pixel interpolation processing, gamma correction, and white balance correction is performed on the imaging signal input from the endoscope 11 and stored in the frame memory 42 as image data. The image data stored in the frame memory 42 is subjected to predetermined image processing by the image processing unit 43 to become an observation image, and is displayed on the monitor 14 via the display control unit 44. The observation image displayed on the monitor 14 is updated every frame period.

  This observation image is a wavelength band of 460 nm to 500 nm that is reflected or scattered from white illumination light consisting of violet light LV, blue light LB, green light LG, and red light LR with almost no absorption by blood hemoglobin. Since this corresponds to an image obtained by imaging a specimen using illumination light with reduced light intensity, the image has high color reproducibility, is bright, and has high blood vessel contrast.

  As described above, the notch characteristic for reducing the light intensity in the wavelength band of 460 nm to 500 nm is incorporated in the optical characteristic of the fourth DM 55d. Therefore, it is not necessary to provide a notch filter, and the device configuration of the light source unit 30 is reduced. It can be downsized.

  In the above embodiment, the notch characteristic for reducing the light intensity in the wavelength band of 460 nm to 500 nm is incorporated in the optical characteristic of the fourth DM55d as shown in FIG. 11, but as shown in FIG. It is also possible to incorporate the optical characteristics of the third DM 55c. However, since the second DM 55b has the threshold λ2 in the wavelength band of 460 nm to 500 nm, the optical characteristic of the second DM 55b cannot incorporate notch characteristics for reducing the light intensity in the wavelength band of 460 nm to 500 nm.

  In the above embodiment, the second to fourth DMs 55b to 55d are arranged in this order from the upstream side (V-LD 53 side). However, the second DM 55b, the fourth DM 55d, and the third DM 55c are arranged in this order, -You may arrange | position LED56a, R-LED56b, V-LED56c, and the 3rd-5th collimator lenses 58c-58e. Since the second DM 55b is for multiplexing the blue light LB, it is necessary to provide the second DM 55b on the upstream side (rotating phosphor 50 side) from the fourth DM 55d or the third DM 55c having the above-described notch characteristics.

  In the above embodiment, the second DM 55b transmits light having a wavelength equal to or greater than the threshold λ2 and reflects light having a wavelength smaller than the threshold λ2, but conversely, reflects light having a wavelength equal to or greater than the threshold λ2. Alternatively, light having a wavelength smaller than the threshold λ2 may be transmitted. In this case, the purple light LV is bent by 90 ° by being reflected by the second DM 55b, and the optical path of the blue light LB transmitted through the second DM 55b is integrated with this optical path. The excitation light LE is excluded from the optical path of the violet light LV by passing through the second DM 55 b and does not enter the condenser lens 59.

  Similarly, the third DM 55c may transmit light having a wavelength longer than the threshold λ3 and reflect light having a wavelength smaller than the threshold λ3. The fourth DM 55d may reflect light having a wavelength longer than the threshold λ4 and transmit light having a wavelength smaller than the threshold λ4. In this case, in order to give the above-mentioned notch characteristics to the fourth DM 55d, as shown in FIG. 13, in the wavelength band larger than the threshold λ4, the light transmittance for the wavelength band of 460 nm to 500 nm is β (for example, β = 70%), and the other light transmittance may be almost 0%.

  Accordingly, each of the second to fourth DMs 55b to 55d generates one of reflection and transmission with respect to light having a wavelength equal to or greater than the threshold, and generates the other of reflection and transmission with respect to light having a wavelength shorter than the threshold. Since the optical characteristics (reflection or transmission) of the second to fourth DMs 55b to 55d can be combined, eight patterns including the above-described embodiment are possible.

  Further, in the case where the fourth DM 55d is provided with a notch characteristic for reducing the light intensity in the wavelength band of 460 nm to 500 nm, as shown in FIG. 14, in addition to the notch characteristic (first notch characteristic), 560 nm to 590 nm. It is possible to provide a second notch characteristic that reduces the light intensity in the wavelength band (from 560 nm to 590 nm). Due to the second notch characteristic, the green light LG and the red light LR are partially attenuated, and the wavelength bands of the green light LG and the red light LR are obtained by the conventional xenon light source and the wavelength selection filter. It is preferable in terms of affinity with conventional equipment. The light attenuation rate of the second notch characteristic may be different from the light attenuation rate (light transmittance α) of the first notch characteristic. Further, the wavelength band of the second notch characteristic is not limited to 560 nm to 590 nm, and may be wider than 550 nm to 600 nm.

Moreover, in the said embodiment, although the fluorescent substance layer 61 shall emit only the green light LG, in addition to the green light LG, you may comprise so that other wavelength band light may be emitted. Hereinafter, an embodiment of an endoscope system including a rotating phosphor having a phosphor layer that emits a plurality of types of light will be described.
[Second Embodiment]
In the second embodiment, a rotating phosphor 70 shown in FIG. 15 is used instead of the rotating phosphor 50 of the first embodiment. The rotating phosphor 70 has a phosphor layer having a first area 71a that emits green light LG (first fluorescence) and a second area 71b that emits blue light LB (second fluorescence) in the recess 62 of the wheel plate 60. 71 is provided. The first region 71a is a region in which, for example, β-SiAlON (β-Si _6-x Al _x O _x N _8-x ) is dispersed as a phosphor material in a binder (not shown), and the excitation light LE And emits green light LG. The second region 71b is a region in which, for example, BAM (BaMgAl ₁₀ O ₁₇ : Eu ²⁺ ) is dispersed as a phosphor material in a binder (not shown), and emits blue light LB upon receiving excitation light LE. .

  As illustrated in FIG. 16, the light source unit 72 of the present embodiment is obtained by deleting the B-LED 56 a, the third collimator lens 58 c, and the second DM 55 b from the configuration of the light source unit 30 illustrated in FIG. 5. Other configurations are the same as those of the first embodiment.

  In the present embodiment, with the rotation of the wheel plate 60, the first region 71a and the second region 71b pass through the irradiation position 64 (see FIG. 15) of the excitation light LE, and the green light LG and the blue light LB alternate. To be emitted. Of the green light LG and blue light LB emitted from the rotating phosphor 70, the component directed to the V-LD 53 side is reflected by the first DM 55a, returned to the rotating phosphor 70, and incident on the second collimator lens 58b. . Of the green light LG and blue light LB, the component going to the side opposite to the V-LD 53 is incident on the second collimator lens 58b as it is.

  The green light LG and the blue light LB emitted from the second collimator lens 58b pass through the third and fourth DMs 55c and 55d and enter the condenser lens 59. When the green light LG and the blue light LB pass through the fourth DM 55d, the light intensity in the wavelength band of 460 nm to 500 nm is reduced due to the notch characteristics of the fourth DM 55d. In the present embodiment, since the second DM 55b is not provided, the excitation light LE passes through the third DM 55c, enters the fourth DM 55d, and is reflected by the fourth DM 55d, so that the green light LG and the blue light LB are reflected. It is excluded from the optical path and does not enter the condenser lens 59.

  The optical paths of the red light LR and the purple light LV emitted from the R-LED 56b and the V-LED 56c are integrated into the optical paths of the green light LG and the blue light LB by the third and fourth DMs 55c and 55d. That is, the fourth DM 55d integrates the optical paths of the green light LG and the red light LR and the optical path of the purple light LV without integrating the optical paths of the green light LG and red LR and the optical path of the excitation light LE.

  Next, drive timings of the light source unit 72 and the image sensor 33 will be described. The controller 40 controls the light source control unit 31 and the imaging drive unit 34, so that the rotation of the rotating phosphor 70, the light emission of the R-LED 56b and the V-LED 56c, and the imaging of the imaging device 33 are controlled in synchronization with each other. Is done.

  The controller 40 controls the light emission timing of the R-LED 56b and the V-LED 56c and the imaging timing of the imaging device 33 based on the detection value of a rotational position detection sensor (not shown) that detects the rotational position of the wheel plate 60. To do.

  Specifically, the controller 40 rotates the wheel plate 60 of the rotating phosphor 70 at a constant period T, drives the V-LD 53, and emits the excitation light LE. The emission intensity of the excitation light LE is constant. As shown in FIG. 17, the first half of the rotation period T is a period during which the first region 71a passes through the irradiation position 64 of the excitation light LE (hereinafter referred to as the first period P1), and the green light LG is Be emitted. The second half of the rotation period T is a period during which the second region 71b passes through the irradiation position 64 (hereinafter referred to as a second period P2), and blue light LB is emitted.

  The controller 40 drives the V-LED 56c only during the first period P1 to generate purple light LV, and drives the R-LED 56b only during the second period P2 to generate red light LR. Thereby, in the first period P1, light (hereinafter referred to as first illumination light) obtained by combining the green light LG and the purple light LV is supplied from the light source unit 30 to the light guide 32 of the endoscope 11. The In the second period P2, light (hereinafter referred to as second illumination light) obtained by combining the blue light LB and the red light LR is supplied from the light source unit 30 to the light guide 32 of the endoscope 11.

  The controller 40 causes the image sensor 33 to perform an imaging operation in each of the first period P1 and the second period P2. That is, the imaging device 33 captures an image of the specimen illuminated with the first illumination light in the first period P1 to generate an imaging signal (hereinafter referred to as the first imaging signal S1), and the second period P2 The specimen illuminated with the illumination light is imaged to generate an imaging signal (hereinafter referred to as a second imaging signal S2).

  Here, since the wavelength bands of the green light LG and the violet light LV included in the first illumination light are separated from each other, the imaging element 33 performs imaging with good color separation. Similarly, the blue light LB and the red light LR included in the second illumination light are separated from each other in wavelength, so that the imaging element 33 captures an image with good color separation.

  The DSP 41 generates image data based on the G signal and B signal included in the first imaging signal S1 and the B signal and R signal included in the second imaging signal S2. The B signal included in the first imaging signal S1 is based on the purple light LV, and the B signal included in the second imaging signal S2 is based on the blue light LB. When generating image data, the B signal is obtained by adding the B signal included in the first imaging signal S1 and the B signal included in the second imaging signal S2 for each identical pixel. Then, image data is generated by performing the above-described signal processing using the B signal, the G signal, and the R signal.

  As shown in FIG. 18, the DSP 41 uses the obtained imaging signal and the imaging signal obtained immediately before the first imaging signal S <b> 1 or the second imaging signal S <b> 2 from the imaging device 33. Image data for one frame is generated. That is, half of the rotation period T (T / 2) is the above-described one frame period.

  Thus, the observation image based on the image data obtained from the first and second imaging signals S1 and S2 is a full-color image. In addition to this observation image, an observation image may be generated only from the first imaging signal S1. Since the first imaging signal S1 is a signal based on the green light LG and the purple light LV, the observation image based on the first imaging signal S1 is a pseudo color image in which the surface blood vessels and the like are emphasized.

  In the second embodiment, the green light LG and the blue light LB are generated by a phosphor and both have high luminance, so that the intensity balance between the green light LG and the blue light LB is maintained.

  Also in the second embodiment, the fourth DM 55d can be arranged on the upstream side (V-LD 53 side) from the third DM 55c. However, when the fourth DM 55d is arranged on the downstream side, the fourth DM 55d has a wavelength of 460 nm to In addition to the first notch characteristic for reducing the light intensity in the wavelength band of 500 nm, it is possible to have the second notch characteristic for reducing the light intensity in the wavelength band of 560 nm to 590 nm. Further, the optical characteristics (reflection or transmission) of the third and fourth DMs 55c and 55d can be changed, and four patterns including the configuration shown in FIG. 16 can be modified.

  In the second embodiment, as shown in FIG. 17, the imaging cycle of the imaging device 33 is half of the rotation cycle T, and the imaging operation is performed individually in the first period P1 and the second period P2, respectively. The imaging cycle of the element 33 may coincide with the rotation cycle T, and one imaging operation may be performed at one rotation cycle T. In this case, since the sample image illuminated with the first illumination light and the sample image illuminated with the second illumination light are mixed and imaged, the color separation of imaging is reduced as compared with the second embodiment. However, the signal processing for generating image data by the DSP 41 is simplified.

  In this case, the R-LED 56b and the V-LED 56c may be constantly driven so that the red light LR and the purple light LV are always lit. Further, the imaging cycle of the image sensor 33 may be made to be an integral multiple of the rotation cycle T. Further, when the rotation period T is sufficiently small with respect to the imaging period, the imaging period may not coincide with an integral multiple of the rotation period T, and the imaging of the imaging element 33 and the rotation of the rotating phosphor 70 may be asynchronous. .

  In the second embodiment, the emission intensity of the excitation light LE by the V-LD 53 is constant, but it is also preferable to change the emission intensity of the excitation light LE between the first period P1 and the second period P2. Since the emission intensity of the green light LG and the blue light LB changes according to the emission intensity of the excitation light LE, by changing the emission intensity of the excitation light LE between the first period P1 and the second period P2, The light quantity ratio between the green light LG and the blue light LB can be changed.

  The light quantity ratio between the green light LG and the blue light LB is preferably changed between the distant view observation and the near view observation. The distant view observation is to observe the distal end portion 19 of the endoscope 11 at a position away from the specimen, and mainly to observe the entire state of the observed site including the positional relationship between the surface blood vessels and the middle-deep blood vessels. It is the purpose. On the other hand, near-field observation is observation at a position where the distal end portion 19 of the endoscope 11 is close to the specimen, and intensive observation of superficial blood vessels where lesions due to early cancer or the like are likely to appear. This is the main purpose.

At the time of distant view observation, since the brightness of the observation image is lower than that at the time of close view observation, it is preferable to increase the light amount ratio R _{G / B} of the green light LG to the light amount of the blue light LB. This is because green light LG has a lower hemoglobin absorption coefficient and scattering coefficient in living tissue than blue light LB, so that it diffuses deeper and wider in living tissue and efficiently illuminates mucous membranes and the like. by.

The change of the light quantity ratio R _{G / B} may be performed based on an input signal from the operation input unit 15, for example. Specifically, the distant view observation mode and the foreground observation mode can be set by the operation input unit 15, and when the distant view observation mode is set, the light amount ratio R _{G / B} is made larger than that in the foreground observation mode. . Instead of this, the exposure amount may be obtained based on the imaging signal acquired by the imaging element 33, and the light amount ratio _{RG / B} may be controlled based on the exposure amount. Specifically, when the exposure amount is equal to or less than a certain value, it is determined that the subject is in a distant view observation state, and when the exposure amount is greater than a certain value, it is determined that the subject is in a near view observation state.
[Third Embodiment]
In the third embodiment, excitation light LE is added to the first region 71a in the phosphor layer 71 in addition to the phosphor material (β-SiAlON or the like) that emits green light LG (first fluorescence) upon receiving excitation light LE. In response, a phosphor material (for example, CASN (CaAlSiN ₃ : Eu ²⁺ )) that emits red light LR (third fluorescence) is contained, and the configuration of the light source unit 72 shown in FIG. The collimator lens 58d and the third DM 55c are deleted.

In the third embodiment, yellow light in which green light LG and red light LR are mixed is emitted from the first region 71a. Other configurations are the same as those of the second embodiment.
[Fourth Embodiment]
In the fourth embodiment, as shown in FIG. 19, a rotating phosphor 80 in which a phosphor layer 81 having first to third regions 81 a to 81 c is provided in a recess 62 of a wheel plate 60 is used. Similar to the first and second regions 71a of the second embodiment, the first and second regions 81a and 81b receive the excitation light LE and receive green light LG (first fluorescence) and blue light LB (second fluorescence). Are generated respectively.

The third region 81c receives the excitation light LE and generates red light LR (third fluorescence). The third region 81c is a region in which, for example, CASN (CaAlSiN ₃ : Eu ²⁺ ) is dispersed as a phosphor material in a binder (not shown).

  As shown in FIG. 20, the light source unit 82 of the present embodiment is obtained by deleting the R-LED 56b, the fourth collimator lens 58d, and the third DM 55c from the configuration of the light source unit 72 shown in FIG. Other configurations are the same as those of the first embodiment.

  In the present embodiment, as the wheel plate 60 rotates, the first region 81a, the second region 81b, and the third region 81c sequentially pass through the irradiation position 64 of the excitation light LE, and the green light LG, blue light LB, red Light LR is emitted in order. When the green light LG, the blue light LB, and the red light LR are transmitted through the fourth DM 55d, the light intensity in the wavelength band of 460 nm to 500 nm is reduced due to the notch characteristics of the fourth DM 55d.

  In the present embodiment, a monochrome image sensor (hereinafter referred to as a monochrome sensor) that does not have a color filter array can be used as the image sensor 33. When a monochrome sensor is used as the imaging element 33, imaging may be performed in accordance with each light emission period of the green light LG, the blue light LB, and the red light LR. In this case, it is preferable that the V-LED 56c is driven to emit purple light LV during the light emission period (second period P2) of the blue light LB.

On the other hand, when a single-plate color image sensor (hereinafter referred to as a color sensor) is used as the image sensor 33, the emission period of the red light LR (the third region 81c passes through the irradiation position 64 of the excitation light LE). In the period), it is preferable to drive the V-LED 56c to emit purple light LV. Since the red light LR and the violet light LV are separated from each other in wavelength band, the image pickup device 33 picks up an image with good color separation.
[Fifth Embodiment]
In the fifth embodiment, as shown in FIG. 21, a phosphor layer 91 composed of first to third phosphor materials 91 a to 91 c and a binder 91 d in which these are dispersed in the recess 62 of the wheel plate 60. Rotating phosphor 90 having The first phosphor material 91a receives the excitation light LE and emits green light LG (first fluorescence). The second phosphor material 91b receives the excitation light LE and emits blue light LB (second fluorescence). The third phosphor material 91c receives the excitation light LE and emits red light LR (third fluorescence).

  As in the fourth embodiment, the light source unit of the present embodiment is obtained by deleting the R-LED 56b, the fourth collimator lens 58d, and the third DM 55c from the configuration of the light source unit 72 shown in FIG. Other configurations are the same as those of the first embodiment.

  In the present embodiment, the phosphor layer 91 emits light (white light) in which the green light LG, the blue light LB, and the red light LR are mixed by irradiating the phosphor layer 91 with the excitation light LE. For this reason, a color sensor is used as the image sensor 33, and a monochrome sensor cannot be used. In the present embodiment, while the wheel plate 60 is rotating, the V-LED 56c is driven to emit the purple light LV constantly. Other configurations are the same as those of the first embodiment.

  Also in the fourth and fifth embodiments, in addition to the first notch characteristic for reducing the light intensity in the wavelength band of 460 nm to 500 nm, the second DM 55d reduces the light intensity in the wavelength band of 560 nm to 590 nm. It is possible to have a notch characteristic. It is also possible to reverse the relationship between reflection and transmission of the optical characteristics of the fourth DM 55d.

  In each of the above embodiments, the peak wavelength of the blue light LB is about 460 nm and the peak wavelength of the green light LG is about 540 nm. However, the peak wavelength of the blue light LB may be 460 nm or less, and the peak wavelength of the green light LG is What is necessary is just 500 nm or more.

  In each of the embodiments described above, the color sensor is provided with the primary color filter array 38, but a complementary color filter array may be provided instead.

  In each of the above embodiments, the first DM 55a is provided separately from the rotating phosphor. However, the first DM 55a may be provided on the back side (V-LD 53 side) of the phosphor layer of the wheel plate.

  In each of the above embodiments, the phosphor is a rotating phosphor that is rotationally driven. However, the phosphor may be fixed and not rotated.

  In each of the above-described embodiments, the light source device and the processor device are configured separately, but may be configured by one device including the light source device and the processor device.

  The first dichroic mirror described in the claims corresponds to the first DM 55a in the embodiment. The first light source described in the claims corresponds to the V-LED 56c or the R-LED 56b, and the specific light corresponds to the violet light LV or the red light LR. The second dichroic mirror described in the claims corresponds to the third DM 55c or the fourth DM 55d. The second light source described in the claims corresponds to the B-LED 56a or the R-LED 56b, and the third dichroic mirror corresponds to the second DM 55b or the third DM 55c. The third light source described in the claims corresponds to the R-LED 56b, and the fourth dichroic mirror corresponds to the third DM 55c.

The configuration according to claim 1 of the claims includes the first configuration in which the second dichroic mirror transmits the fluorescence and reflects the specific light, and the second configuration that reflects the fluorescence and transmits the specific light. Is included. Hereinafter, the first and second configurations will be described as additional items 1 and 2, respectively.
[Additional Item 1]
An excitation light source that emits excitation light;
A phosphor that emits fluorescence when irradiated with the excitation light;
A first dichroic mirror that is disposed between the excitation light source and the phosphor, transmits the excitation light, and reflects a component of the fluorescence toward the excitation light source;
A first light source that emits specific light having a wavelength band different from that of the fluorescence;
Light intensity in a wavelength band of 460 nm or more and 500 nm or less, which is arranged on the optical path of the fluorescence, integrates the optical path of the fluorescence and the optical path of the violet light by transmitting the fluorescence and reflecting the specific light A second dichroic mirror having a characteristic of reducing
An endoscope light source device comprising:
[Additional Item 2]
An excitation light source that emits excitation light;
A phosphor that emits fluorescence when irradiated with the excitation light;
A first dichroic mirror that is disposed between the excitation light source and the phosphor, transmits the excitation light, and reflects a component of the fluorescence toward the excitation light source;
A first light source that emits specific light having a wavelength band different from that of the fluorescence;
The light intensity of the wavelength band of 460 nm or more and 500 nm or less, which is arranged on the optical path of the fluorescence, integrates the optical path of the fluorescence and the optical path of the violet light by reflecting the fluorescence and transmitting the specific light. A second dichroic mirror having a characteristic of reducing
An endoscope light source device comprising:

DESCRIPTION OF SYMBOLS 10 Endoscope system 11 Endoscope 12 Processor apparatus 13 Light source apparatus 30 Light source part 32 Light guide 32a Incident end 33 Imaging element 33a Imaging surface 38 Color filter array 50 Rotary fluorescent substance 55a-55d 1st-4th DM
58a to 58e First to fifth collimator lenses 60 Wheel plate 61 Phosphor layer 64 Irradiation position 70 Rotating phosphor 71 Phosphor layer 71a, 71b First and second regions 80 Rotating phosphor 81 Phosphor layer 81a to 81c First To third region 90 rotating phosphor 91 phosphor layer 91a to 91c first to third phosphor material 91d binder

Claims (9)

An excitation light source that emits excitation light;
A phosphor that emits fluorescence when irradiated with the excitation light, and as the fluorescence, a phosphor that emits green light and red light; and
A first light source that emits specific light having a wavelength band different from that of the fluorescence;
A second dichroic mirror that integrates the optical path of the fluorescence and the optical path of the specific light;
An endoscope light source device comprising:   2. The inner surface of claim 1, wherein the second dichroic mirror integrates the optical path of the fluorescence and the optical path of the specific light without integrating the optical path of the fluorescence and the optical path of the excitation light. Endoscopic light source device.   The endoscope light source device according to claim 1, wherein the specific light is violet light.   The light source device for an endoscope according to any one of claims 1 to 3, wherein the second dichroic mirror has a characteristic of reducing light intensity in a wavelength band of 460 nm or more and 500 nm or less.   5. The endoscope light source device according to claim 1, wherein the second dichroic mirror further has a characteristic of reducing a light amount of light in a wavelength band of 560 nm or more and 590 nm or less.   6. The endoscope according to claim 1, wherein the phosphor includes a phosphor layer in which a phosphor material that emits green light and a phosphor material that emits red light are dispersed in a binder. Light source device.   The endoscope light source device according to claim 1, wherein the phosphor is fixed.   The first dichroic mirror that is disposed between the excitation light source and the phosphor, transmits the excitation light, and reflects a component of the fluorescence toward the excitation light source side. The endoscope light source device described. An excitation light source that emits excitation light;
A phosphor that emits fluorescence when irradiated with the excitation light, and as the fluorescence, a phosphor that emits green light and red light; and
A first light source that emits specific light having a wavelength band different from that of the fluorescence;
A light source device comprising: a second dichroic mirror disposed on the fluorescent light path and integrating the fluorescent light path and the specific light optical path;
An endoscope having an image sensor that images reflected light from an observation site irradiated with the fluorescence and the specific light;
A control unit for controlling the light source device and the imaging element;
An endoscope system comprising:

Images