JP2020078667A - Endoscope apparatus - Google Patents

Abstract

To acquire desired information of a biological tissue in a further clear state suited for a diagnosis when observing the biological tissue by white light and special light.SOLUTION: An endoscope apparatus includes: a first light source 51 defining a semiconductor light-emitting element as a light-emitting source; a second light source 53 defining a semiconductor light-emitting element having a different light emission wavelength from that of the first light source 51, as a light-emitting source; a wavelength conversion member 57 excitingly emitting light by outgoing light from at least one of the first light source 51 and the second light source 53; and light quantity rate change means 55 for changing a light quantity rate of the outgoing light from the first light source 51 and the outgoing light from the second light source 53. The endoscope apparatus optionally generates the outgoing light from the first light source 51 and the outgoing light from the second light source 53 to provide illumination light suited for the diagnosis according to absorption characteristics and scatter characteristics of a biological tissue. This configuration can thus acquire desired tissue information of the biological tissue in a further clear state.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an endoscope illumination device and an endoscope device.

  A general endoscope device guides light from a lamp of a light source device to a distal end portion of the endoscope by a light guide provided inside an endoscope insertion portion to be inserted into a subject, and The observation site of the subject is illuminated by emitting light from the illumination window at the tip of the mirror. White light is usually used for observing living tissues, but in recent years, the condition of mucosal tissues is highlighted by irradiating with light of a specific narrow band wavelength, or from a fluorescent substance previously administered. Endoscope devices capable of performing special light observation for observing autofluorescence are used (Patent Documents 1 and 2). With this type of endoscopic device, by irradiating living tissue with special light, for example, new blood vessels that occur in the mucosal layer or submucosal layer can be observed, and a depiction of the fine structure of the mucosal surface that cannot be obtained with normal observation images. Will be possible.

  In the above-mentioned Patent Documents 1 and 2, emitted light from a white light source such as a xenon lamp is extracted as a special light by extracting only a specific wavelength band by a color filter. As the white light source, a laser light source can be used in addition to the xenon lamp, and for example, a light emitting device that generates white light by combining a blue laser light source and a phosphor that excites and emits the blue laser light as excitation light has been proposed. (Patent Document 3).

  However, in the endoscope apparatuses of Patent Documents 1 and 2, the light from the white light source is time-divided by the color filter, and the light of different wavelength bands (R, G, B light, etc.) is emitted in the field sequential manner. Has become. Therefore, in order to obtain a full-color observation image, it is necessary to combine captured images of a plurality of frames (R, G, B), which is an obstacle to increasing the frame rate of the observation image. Further, since the color filter absorbs the light to generate the illumination light, a decrease in the light amount is unavoidable, which causes a noise component of the observed image to increase. Although it is possible to reduce the frame rate to increase the sensitivity, in that case, the image tends to be blurred.

  On the other hand, in the special optical diagnosis, tissue information and the like on the surface layer and the deep layer of the living tissue are important observation targets. For example, in gastrointestinal cancer, tumor blood vessels appear in the superficial portion of the mucous membrane from an early stage, and the tumor blood vessels have swelling, meandering, and an increase in the density of blood vessels as compared with the blood vessels that appear in the normal superficial portion. Therefore, the type of tumor can be distinguished by closely examining the properties of blood vessels. However, in the endoscopic device using the color filter, when it is desired to observe the tissue information of the surface layer part of the biological tissue, it is difficult to limit the transmission wavelength band of the color filter to a specific narrow band, and, The illumination light limited to a narrow band cannot obtain a sufficient amount of light, which is disadvantageous in that the quality of the observed image deteriorates.

Japanese Patent No. 3583731 Japanese Patent Publication No. 6-40174 JP, 2006-173324, A

  The present invention provides a light source device for an endoscope and an endoscope device that can obtain desired tissue information of a living tissue in a clearer state suitable for diagnosis when observing the living tissue with white light or special light. With the goal.

The present invention has the following configurations.
(1) An endoscope illumination device that obtains illumination light by using emitted light from a plurality of light sources,
A first light source having a semiconductor light emitting element as a light emitting source;
A second light source using a semiconductor light emitting element having an emission wavelength different from that of the first light source as a light source,
A wavelength conversion member that is excited and emitted by light emitted from at least one of the first and second light sources;
A light quantity ratio changing means for changing a light quantity ratio between the light emitted from the first light source and the light emitted from the second light source,
An illuminating device for endoscopes.
(2) An illumination optical system that emits illumination light from the endoscope illumination device from the tip of the endoscope insertion portion,
An imaging optical system including an imaging device that receives light from the illuminated area irradiated with the illumination light and outputs an image signal,
An endoscopic device provided with.

  According to the endoscope light source device and the endoscope device of the present invention, when observing a living tissue using white light or special light of a specific wavelength band, desired tissue information of the living tissue is more suitable for diagnosis. It can be obtained in a clear state.

FIG. 1 is a schematic configuration diagram of an endoscope device using an endoscope light source device for explaining an embodiment of the present invention. FIG. 2 is a block configuration diagram of the endoscope device shown in FIG. 1. It is a graph which shows the emission spectrum of the laser beam from a violet laser light source, the blue laser beam from a blue laser beam source, and the light after wavelength conversion of the blue laser beam by the fluorescent substance. It is a detailed block diagram of an image processing part. It is explanatory drawing which represented typically the blood vessel of the mucous membrane surface layer of a biological tissue. It is explanatory drawing which shows the schematic example of a display of the observation image by an endoscope apparatus. It is a magnified observation image by white light of the inside of the lips observed by the endoscope apparatus. It is a magnified observation image of a light amount ratio of 50:50 on the inner side of the lips observed by the endoscope apparatus. It is a magnified observation image with a light amount ratio of 75:25 on the inside of the lips observed by an endoscope apparatus. It is explanatory drawing which shows the example of the display screen of the display part which displays the observation image by an endoscope apparatus. It is explanatory drawing which shows the other example of the display screen of the display part which displays the observation image by an endoscope apparatus. It is a graph which shows the relationship between the electric current applied to a light source, and the amount of light emission. It is a graph which shows the pulse current superimposed waveform of an applied current. It is explanatory drawing which shows various drive waveforms (a), (b), (c) by pulse modulation control. It is a graph which shows the example of control which makes the light-emission quantity of a light source become the maximum alternately. 6 is a graph showing a schematic relationship between the absorption wavelength band of hemoglobin and the emission wavelength of each light source. A state of the display image on the display unit when the endoscope operator moves the endoscope insertion part inside the subject, observes with narrow band light at a desired observation position, and moves to the next observation position. It is an explanatory view showing roughly. It is explanatory drawing which shows the example which arrange|positions a normal image and a narrow band light image in each separate area|region in the same screen, and displays them simultaneously. It is explanatory drawing which shows the example which displays the narrow-band light image of a desired range on a normal image, and displays it simultaneously. It is explanatory drawing which shows the light amount ratio table which registered the light amount ratio with respect to the operator of the endoscope. It is explanatory drawing which shows the example which displays the preset light quantity ratio on a display part. It is operation|movement explanatory drawing of a changeover switch. It is explanatory drawing which shows the color conversion coefficient table with respect to a light quantity ratio. 3 is a graph showing absorption spectra of hemoglobin Hb having a low oxygen concentration and oxygen-saturated oxyhemoglobin HbO ₂ . FIG. 3 is a block diagram showing a configuration example of a light source device including a plurality of laser light sources and an endoscope. It is a block diagram which shows the structural example of the light source device which integrated the optical path, and an endoscope. It is a graph which shows the example of the light emission spectrum by the light source device and fluorescent substance shown in FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic configuration diagram of an endoscope device using a light source device for an endoscope for explaining an embodiment of the present invention, and FIG. 2 is a block configuration diagram of the endoscope device shown in FIG. ..
The endoscope apparatus 100 shown in FIG. 1 includes an endoscope 11 and a control device 13 to which the endoscope 11 is connected. A display unit 15 that displays image information and the like and an input unit 17 that receives an input operation are connected to the control device 13. The endoscope 11 is an electronic endoscope that includes an illumination optical system that emits illumination light from the tip of the endoscope insertion portion 19 and an imaging optical system that includes an imaging element that images the observed region.

  The endoscope 11 includes an endoscope insertion portion 19 to be inserted into a subject, a bending operation of the tip of the endoscope insertion portion 19, suction from the tip of the endoscope insertion portion 19, air supply/water supply, etc. The operation unit 23 for performing the operation of, the connector unit 25 that detachably connects the endoscope 11 to the control device 13, and the universal cord unit 27 that connects the operation unit 23 and the connector unit 25. Although not shown, various types of channels are provided inside the endoscope 11, such as a forceps channel for inserting a tissue sampling treatment tool and the like, and an air/water feeding channel.

  The endoscope insertion portion 19 includes a flexible portion 31 having flexibility, a bending portion 33, and a tip portion (hereinafter, also referred to as an endoscope tip portion) 35. Irradiation openings 37A and 37B for irradiating the observation area with light, and a CCD (charge coupled device) image sensor and a CMOS (Complementary Metal-Oxide Semiconductor) for acquiring image information of the observation area are provided in the endoscope distal end portion 35. An image sensor 21 such as an image sensor is arranged. An imaging member 39 such as an objective lens is attached to the image sensor 21.

  The bending portion 33 is provided between the flexible portion 31 and the distal end portion 35, and is bendable by a wire operation from the operation portion 23 or an actuator operation operation. The bending portion 33 can be bent in an arbitrary direction and an arbitrary angle according to the site of the subject in which the endoscope 11 is used, and the like, and the irradiation ports 37A and 37B of the endoscope distal end portion 35 and the image pickup device 21 can be bent. The observation direction can be directed to a desired observation site. Although not shown, cover glasses and lenses are arranged at the irradiation ports 37A and 37B of the endoscope insertion portion 19.

  The control device 13 includes a light source device 41 that generates illumination light to be supplied to the irradiation openings 37A and 37B of the endoscope distal end portion 35, and a processor 43 that performs image processing of an image signal from the image pickup device 21, and the above-mentioned display. The unit 15 and the input unit 17 are connected. The processor 43 performs image processing on the image pickup signal transmitted from the endoscope 11 based on an instruction from the operation unit 23 or the input unit 17 of the endoscope 11 to generate a display image on the display unit 15. Supply.

  Inside the endoscope 11, optical fibers 45A and 45B for introducing illumination light from the light source device 41 and a scope cable 47 connecting the image pickup device 21 and the processor 43 are inserted. Although not shown, various signal lines from the operation unit 23 and tubes such as air supply and water supply channels are also connected to the control device 13 and the like via the universal cord unit 27, the connector unit 25, and the like. As shown in FIG. 2, the connector 25 on the endoscope 11 side is detachably connected to connector portions 26A and 26B provided in the light source device 41 and the processor 43, respectively.

  As shown in FIG. 2, the light source device 41 includes a blue laser light source (first light source) 51 having a central wavelength of 445 nm and a violet laser light source (second light source) 53 having a central wavelength of 405 nm as light emitting sources. .. The light emission from the semiconductor light emitting element of each of the light sources 51 and 53 is individually controlled by the light source control unit 55, and the light amount ratio between the emitted light of the blue laser light source 51 and the emitted light of the violet laser light source 53 is changed. It's free.

  For the blue laser light source 51 which is the first light source and the violet laser light source 53 which is the second light source, a broad area type InGaN laser diode can be used, and an InGaNAs laser diode or a GaNAs laser diode is used. You can also Further, a light emitting body such as a light emitting diode may be used as the light source.

  The laser light emitted from each of the light sources 51 and 53 is input to the optical fiber by a condenser lens (not shown), and is transmitted through the connector section 26A and the connector 25 (see FIG. 1) on the endoscope 11 side. The fibers 45</b>A and 45</b>B respectively propagate to the endoscope distal end portion 35 (see FIG. 1) of the endoscope 11. Then, the laser light from the blue laser light source 51 is applied to the phosphor 57, which is a wavelength conversion member arranged in the endoscope distal end portion 35, and the laser light from the violet laser light source 53 is deflected/diffused by the light. Is irradiated.

The optical fibers 45A and 45B are multimode fibers, and as an example, a thin cable having a core diameter of 105 μm, a clad diameter of 125 μm, and a diameter of φ0.3 to 0.5 mm including a protective layer serving as an outer cover can be used.

The phosphor 57 is made of a plurality of types of phosphors that absorb part of the blue laser light from the blue laser light source 51 and excite and emit green to yellow light (for example, YAG phosphor, BAM (BaMgAl ₁₀ O ₁₇ ), or the like. (Including fluorescent substance). As a result, the green to yellow excitation light that uses the blue laser light from the blue laser light source 51 as the excitation light and the blue laser light that has not been absorbed by the phosphor 57 and has been transmitted are combined, and white (pseudo white) illumination light is obtained. Becomes If a semiconductor light emitting element is used as an excitation light source as in this configuration example, white light of high intensity can be obtained with high luminous efficiency, and the intensity of white light can be easily adjusted. Moreover, changes in color temperature and chromaticity of white light are reduced.

  As the blue laser light source 51, the phosphor 57, and the optical fiber 45A connecting them, for example, “Micro White” (trade name) manufactured by Nichia Corporation can be used.

  Further, the light deflection/diffusion member 59 may be any material that allows the laser light from the violet laser light source 53 to pass therethrough, and for example, a resin material having transparency or glass or the like is used. Further, the light deflecting/diffusing member 59 has a configuration in which a light diffusing layer in which fine irregularities or particles having different refractive indices (filler or the like) are mixed is provided on the surface of a resin material or glass, or a semitransparent material. May be used. As a result, the transmitted light emitted from the light deflection/diffusion member 59 becomes illumination light having a narrow band wavelength with a uniform amount of light within a predetermined irradiation region.

  The fluorescent substance 57 and the light deflecting/diffusing member 59 are caused by speckles generated by the coherence of the laser light, and thus superimpose noise that interferes with image capturing and flickering when displaying a moving image. The phenomenon of can be prevented. In addition, the fluorescent substance 57 has a particle diameter with respect to the fluorescent substance itself and the filler in the infrared region in consideration of the difference in refractive index between the fluorescent substance that constitutes the fluorescent substance and the fixing/solidifying resin that is the filler. However, it is preferable to use a material having low absorption and high scattering. As a result, the scattering effect is enhanced for light in the red and infrared regions without lowering the light intensity, optical path changing means such as a concave lens is not required, and optical loss is reduced.

  FIG. 3 is a graph showing emission spectra of the laser light from the violet laser light source 53, the blue laser light from the blue laser light source 51, and the blue laser light after the wavelength conversion by the phosphor 57. The purple laser light from the purple laser light source 53 is represented by a bright line (profile A) with a central wavelength of 405 nm. Further, the blue laser light from the blue laser light source 51 is represented by a bright line with a central wavelength of 445 nm, and the excitation light emitted from the phosphor 57 by the blue laser light is a spectrum whose emission intensity increases in a wavelength band of approximately 450 nm to 700 nm. It has an intensity distribution (profile B). The white light described above is formed by the profile B of the excitation light and the blue laser light.

  Here, the white light referred to in the present specification is not limited to one that includes all wavelength components of visible light strictly, and may be any light that includes light in a specific wavelength band such as R, G, and B. For example, light including a wavelength component from green to red, light including a wavelength component from blue to green, and the like are also broadly included.

  That is, in the endoscope apparatus 100, the emission intensity of the profile A and the profile B is relatively increased or decreased to generate the illumination light, so that the illumination light having different characteristics is obtained according to the mixing ratio of the profiles A and B. be able to.

  Returning to FIG. 2 again, description will be made. As described above, the illumination light formed by the blue laser light source 51, the phosphor 57, and the violet laser light source 53 is emitted from the tip portion of the endoscope 11 toward the observed region of the subject. Then, the state of the observed region irradiated with the illumination light is imaged on the image pickup device 21 by the image pickup lens 61.

  The image signal output from the image sensor 21 after image capturing is converted into a digital signal by the A/D converter 63 and input to the image processing unit 65 of the processor 43. The image processing unit 65 converts the input image signal into image data, performs appropriate image processing, and generates desired output image information. Then, the obtained image information is displayed on the display unit 15 as an endoscope observation image through the control unit 67. Further, if necessary, the data is recorded in the recording device 69 including a memory and a storage device.

  The recording device 69 may be built in the processor 43 or may be connected to the processor 43 via a network. The information of the endoscopic observation image recorded in the recording device 69 is also recorded with the information of the light amount ratio at the time of imaging. As a result, it is possible to perform accurate image interpretation on the recorded endoscopic observation image after endoscopic observation, and it is also possible to perform appropriate image processing such as standardizing the image according to the light amount ratio. It is possible to expand the range of utilization of endoscopic observation images. In particular, if the spectral reflectance is estimated by artificially increasing the number of bands (R, G, B) on the basis of a plurality of pieces of information with different light intensity ratios of the spectrum, it is possible to separate a smaller color difference. ..

  FIG. 4 shows a detailed block diagram of the image processing unit. The image signal from the image sensor 21 input to the image processing unit 65 is first input to the brightness calculation unit 65a. The brightness calculator 65a obtains brightness information such as maximum brightness, minimum brightness, screen average brightness of the image signal, and normalizes the brightness. If the brightness of the image signal is too low or too high, a correction signal is output to the light source control unit 55 to increase or decrease the light emission amount of each of the light sources 51 and 53 so that the image signal has a desired brightness level. ..

  Next, the color matching unit 65b adjusts the normalized image data so that the image tone becomes a desired tone. For example, when the image signal consists of R, G, and B color signals, the intensity balance of the R, G, and B color signals is adjusted. In the above light source device 41, the light source control unit 55 controls the light emission amounts of the blue laser light source 51 and the violet laser light source 53, respectively, and the light amounts of the emitted light of the blue laser light source 51 and the emitted light of the violet laser light source 53 are controlled. The ratio can be changed arbitrarily. Therefore, the tint of the illumination light and the total illuminance may change depending on the set light amount ratio, so the brightness calculation unit 65a and the color matching unit 65b correct the image signal according to the set light amount ratio. The color tone and brightness of the observed image are maintained at a predetermined constant level.

  Then, the image calculation unit 65c performs a predetermined or requested image calculation, and the display image generation unit 65d generates output image information and outputs the result to the control unit 67.

Next, an example in which the endoscope device 100 is used for observing a blood vessel image of the surface layer of a biological tissue will be described.
FIG. 5 is an explanatory view schematically showing blood vessels in the mucosal surface layer of living tissue. It is reported that the mucosal surface layer of the biological tissue is formed between the blood vessel B1 in the deep mucosa and the capillary B2 such as the resinous vascular network up to the mucosal surface layer, and the lesion of the biological tissue appears in the microstructure of the capillary blood vessel B2. Has been done. Therefore, in recent years, an endoscopic apparatus has been used to image-enhance and observe capillaries in the mucosal surface layer with light of a specific narrow band wavelength, and early detection of micro-lesions and diagnosis of lesion areas have been attempted.

By the way, when the illumination light is incident on the biological tissue, the incident light diffusely propagates in the biological tissue, but the absorption/scattering characteristics of the biological tissue have wavelength dependence, and the shorter the wavelength, the more the scattering characteristic becomes. Tends to be stronger. That is, the depth of light changes depending on the wavelength of the illumination light. On the other hand, blood flowing through blood vessels has a maximum absorption at a wavelength around 400 to 420 nm, and a large contrast can be obtained. For example, in the wavelength range λa near the wavelength of 400 nm of the illumination light, blood vessel information from the capillaries in the mucosal surface layer is obtained, and in the wavelength range λb near the wavelength of 500 nm, blood vessel information including deeper blood vessels is obtained. Therefore, a light source having a center wavelength of 360 to 800 nm, preferably 365 to 515 nm, and more preferably a center wavelength of 400 to 470 nm is used for observing blood vessels on the surface layer of the biological tissue.

  Therefore, as shown in the schematic display example of the observation image by the endoscope apparatus in FIG. 6, in the observation image when the illumination light is white light, a blood vessel image of a relatively deep mucous membrane is obtained, while the mucosal surface layer is obtained. The fine capillaries in the image appear blurry. On the other hand, in the observation image in the case where the narrow band illumination light having only the short wavelength is used, the fine capillaries on the surface layer of the mucous membrane can be clearly seen.

  In the present configuration example, the light source control unit 55 (see FIG. 2) of the endoscope apparatus 100 allows the light amount ratio of the emitted light by the blue laser light source 51 with the central wavelength of 445 nm and the violet laser light source 53 with the central wavelength of 405 nm to be freely changeable. ing. The light amount ratio can be changed, for example, by operating the switch 89 provided on the operation unit 23 of the endoscope 11 shown in FIG. 1, and the image can be emphasized so that the capillaries in the mucosal surface layer can be observed more easily. That is, when the blue laser light source 51 has a large amount of blue laser light component, the blue laser light and the excitation light emitted by the fluorescent substance 57 result in illumination light with a large amount of white light component, as in the white light observation image of FIG. An observation image is obtained. However, since the blue laser light, which is a narrow band light, is mixed in the illumination light, the observation image in which the surface capillaries are image-enhanced is obtained.

  Further, when the violet laser light component by the violet laser light source 53 is large, an observation image such as the narrow band light observation image of FIG. 6 is obtained. Then, by increasing/decreasing the light quantity ratio of the emitted light of the blue laser light source 51 and the violet laser light source 53, that is, increasing/decreasing the ratio of the violet laser light component to all the illumination light components, the fine capillaries on the mucosal surface layer are removed. Observation with continuous highlighting can be performed.

  Therefore, the more violet laser light component is, the finer capillaries contained in the thin depth region of the mucosal surface layer are more clearly projected in the observation image, and as the violet laser light component is decreased, it is directed from the mucosal surface layer to the deep layer. Blood vessel information included in a wide depth region is displayed. As a result, the blood vessel distribution in the depth direction can be displayed in a pseudo manner from the mucous membrane surface layer, and the blood vessel information in the depth direction of the observation site can be extracted as continuous information corresponding to each depth range. .. In particular, in this configuration example, blood vessel information obtained by the blue laser light and blood vessel information of the further surface layer obtained by the violet laser light are extracted together, and both can be compared by the image display of these information, so observation with the blue laser light is possible. It is possible to observe the blood vessel information including the blood vessels in the superficial layer, which was not possible, while enhancing the visibility.

  Further, in the distal end portion 35 (see FIG. 1) of the electronic endoscope in which the image pickup device 21 is arranged, the amount of heat generation is increasing with the increase in power consumption due to the recent increase in the number of pixels, the increase in frame rate, etc. The light that can be emitted from the tip portion 35 is also limited. Among them, changing the light quantity ratio of each light source to increase the required light emission while suppressing the total light quantity of the illumination light is dependent on, for example, only image processing, resulting in a noisy image only. It is possible to solve problems such as not being able to obtain.

  Here, FIGS. 7A, 7B, 7C, and 7C show magnified images of the inside of the labyrinth observed by the endoscope apparatus 100 under the same image processing conditions with the same light amount. In the figure, an observation image (FIG. 7a) by white illumination light composed of a blue laser light having a central wavelength of 445 nm and excitation light of a phosphor, a violet laser light having a central wavelength of 405 nm, and a blue laser light having a central wavelength of 445 nm is shown. An observation image (FIG. 7b) when the light amount ratio is 50:50 and an observation image (FIG. 7c) when the light amount ratio between the violet laser light having a central wavelength of 405 nm and the central wavelength 445 nm is 75:25 are shown. There is. Note that, in FIGS. 7B and 7C as well, the excitation light emitted from the phosphor that uses the blue laser light having the central wavelength of 445 nm as the excitation light is included in the illumination light.

  In the observation image of FIG. 7, the observation depth from the surface layer becomes shallower in the order of a→b→c depending on the wavelength of the illumination light, and the amount of projection of fine capillaries increases. That is, as the ratio of the violet laser light in the illumination light is increased, an image in which the surface capillaries are more emphasized is obtained, and the capillaries and the mucosa fine pattern of the mucosa surface layer can be observed more clearly by increasing the contrast. You can In addition, since the light intensity ratio of the blue laser light and the violet laser light can be freely changed in a stepless manner, it is possible to infer a three-dimensional blood vessel structure in the mucosal surface layer from the change in the observed image when the light intensity ratio is continuously changed. It is easy to selectively and clearly display a desired observation target.

  For such violet light and blue light having wavelength bands close to each other, it is possible to increase or decrease the light amount only in the violet region by distinguishing it from the light in the blue region. It is difficult to realize with wavelength limiting means. When the emission spectrum is narrowed in the optical path by using the wavelength limiting means, the light amount of the original halogen lamp or xenon lamp itself is small and the light amount in the purple region is further insufficient. Further, if the half-value width of the emission spectrum is widened in order to increase the light quantity in the purple region, the narrowing of the illumination light band cannot be achieved, and the image enhancement of the desired blood vessel becomes insufficient.

  When the amount of illumination light is insufficient, generally, the sensitivity of the image sensor can be increased or the frame rate can be reduced to cope with the insufficient amount of light. There is a disadvantage that the noise component increases. Further, if the frame rate is decreased to increase the sensitivity, the blurring becomes large, which makes it difficult to see the observed image. In this configuration example, since the laser light is used as the light source, the high-intensity illumination light is constantly obtained, the observed image can be brightened, and the image quality with low noise can be obtained. Then, even when imaging a distant view, necessary and sufficient illuminance can be obtained.

The light amount ratio is changed by controlling the light sources 51 and 53 by the light source control unit 55 shown in FIG. 2. Next, a method of changing the light amount ratio by the operator while observing the observation image will be described with reference to FIG. , FIG. 9 will be described.
FIG. 8 shows an example of the display screen 71 of the display unit 15 which displays an observation image by the endoscope apparatus 100. On the display screen 71, an endoscope image area 73 for displaying an observation image by the endoscope device, a normal image switching button 75 for displaying an observation image by normal white light illumination in the endoscope image area 73, a purple laser A narrow band light image switching button 77 for displaying an observation image by the narrow band illumination light of light is provided, and further, an adjustment bar 79 and a knob 81 for adjusting the light amount ratio are provided. Then, based on an instruction from the input unit 17 such as a mouse or a keyboard, the knob 81 is slid in the adjustment bar 79 and the light amount ratio is adjusted so that a desired observation image is obtained.

  The control unit 67 determines the light quantity ratio according to the position of the knob 81 of the adjustment bar 79, and drives the light sources 51 and 53 so that the light quantity emitted from the light sources 51 and 53 corresponds to the light quantity ratio. Here, the relationship between the light quantity ratio and the emitted light quantity of each of the light sources 51 and 53 is stored in the storage unit 83 (see FIG. 2) as a light quantity ratio correspondence table, and the control unit 67 corresponds to the light quantity ratio of the storage unit 83. The amount of light emitted from each of the light sources 51 and 53 is obtained by referring to the table.

  As described above, when increasing or decreasing the light amount of each of the light sources 51 and 53 (see FIG. 1) to set a desired light amount ratio, the control unit 67 is prestored based on the light amount ratio set on the display screen 71. The emitted light quantities of the light sources 51 and 53 are determined by referring to the light quantity ratio correspondence table. Accordingly, the amount of light emitted from each of the light sources 51 and 53 can be set to a desired light amount ratio by a simple operation without the operator of the endoscope directly setting the amount.

  Further, as shown in FIG. 9, the light amount ratio may be changed by substituting the setting section 85 for various adjustments of the intensity balance, brightness, and contrast of the R, G, and B color components of the image signal, Alternatively, it may be used in combination with adjustment of the knob 81 for changing the light amount ratio. According to this, it is possible to display a desired observation target by pseudo-colorizing it and to display it by arbitrarily emphasizing the image, improving the degree of freedom in changing the display image, and making the image easier to diagnose.

Next, a method of driving the light sources 51 and 53 by the light source controller 55 will be described.
The light source control unit 55 shown in FIG. 2 controls the amount of light emitted from each of the light sources 51 and 53 based on an instruction from the input unit 17. Each of the light sources 51 and 53 has a relationship R1 between the applied current and the amount of light emission as shown in FIG. 10, and the desired amount of light emission is obtained by controlling the current applied to each of the light sources 51 and 53. . For example, in order to obtain the light emission amount La, the light emission amount Lb based on the relationship R1 is secured with the applied current Ib, and the difference ΔL between the light emission amount Lb and La as the fine adjustment allowance is pulse-modulated to the applied current. It is obtained by superposing the generated pulse currents.

  For example, as shown in the pulse current superimposed waveform of the applied current in FIG. 11, the light emission amount La is obtained by the pulse current with the applied current Ib as the bias. By such bias current control and pulse modulation control, it is possible to secure a wide dynamic range of light emission amount that can be set.

  Various drive waveforms can be used for the pulse modulation control in this case. For example, by using a pulse waveform that repeatedly turns on and off in synchronization with the light accumulation time for one frame of the image of the image sensor as shown in FIG. 12A, it is less likely to be affected by the dark current of the CCD or CMOS image sensor, The sharpness of the image becomes high. Further, by using a pulse waveform having a sufficiently fast cycle with respect to the light accumulation time as shown in FIG. 12B, it is possible to reduce the occurrence of flicker related to image display, and moreover, an image due to laser speckle. Noise can also be reduced. Furthermore, as shown in FIG. 12C, the ON period of the pulse waveform of FIG. 12A is the pulse waveform of the fast cycle of FIG. 12B, and the mixed pulse waveforms of FIG. 12A and FIG. By using, it is possible to enjoy the above effects other than flicker reduction.

  Further, as shown in FIG. 13, when the light sources 51 and 53 are alternately turned on and the light emission amount is controlled to be maximum alternately, the maximum drive power of the light source device 41 including the light sources 51 and 53 is suppressed. It is possible to reduce the burden on the living body which is the subject. Further, it is possible to individually acquire the captured images by the illumination light of each of the light sources 51 and 53, and in that case, it is possible to perform the inter-image calculation of the acquired images, and the degree of freedom in image processing is improved.

FIG. 14 shows a schematic relationship between the absorption wavelength band of hemoglobin and the emission wavelengths of the light sources 51 and 53.
Hemoglobin contained in blood has a maximum absorption at a wavelength near 400 to 420 nm as described above, and is included in the absorption wavelength band of hemoglobin, or from each light source 51, 53 having an emission wavelength close to the absorption wavelength band. The emitted light of can capture the blood vessel information with high contrast. In addition, the emission wavelengths of the light sources 51 and 53 are set to the same absorption rate across the absorption wavelength band of hemoglobin, so that the intensity of the blood vessel information is affected by the light amount ratio of the light sources 51 and 53. Never. That is, the detection sensitivity of the blood vessel image itself is kept constant even if the light quantity ratio of the light sources 51 and 53 is changed.

  Then, by avoiding the maximum peak wavelength of the absorption wavelength band of hemoglobin and using light in the wavelength region having an appropriate absorptance in the skirt region of the absorption wavelength band as illumination light, bleeding occurred from the biological tissue in the observation region. In this case, it is possible to prevent the observed image from becoming dark due to the influence of absorption by the blood that has exuded to the tissue surface layer.

  The observation image obtained by the illumination by the narrow band light of the violet laser light and the illumination by the white light described above can be instantly switched for each frame. FIG. 15 shows the display unit 15 when the operator of the endoscope moves the endoscope insertion portion inside the subject to perform observation with narrow band light at a desired observation position and moves it to the next observation position. The state of the display image (see FIGS. 1 and 2) is schematically shown.

  Switching from the normal display image by the white light observation to the display image by the narrow band light observation and the switching in the opposite direction are performed by one frame of the captured image of the image sensor 21 (full color image of three colors of R, G and B). It is possible to switch in units. Therefore, even when observing while moving the endoscope insertion portion, an image without color misregistration can be displayed in real time, and the operator does not feel uncomfortable. That is, it is possible to provide a good observation image that reliably follows the rapid movement of the endoscope, and improve the operability of the endoscope device.

  Further, as the display pattern of the observation image on the display unit 15, a normal image during white light observation and a narrow band light image during narrow band light observation can be freely arranged. For example, as shown in FIG. 16, a normal image and a narrow band light image are arranged in separate areas on the same screen and are displayed simultaneously, so that the normal image and the narrow band light in which specific information is emphasized are displayed. It becomes easy to compare and observe the optical image. In this case, the blue laser light source 51 is turned on for imaging for a normal image with white light, and in the next frame, the blue laser light source 51 and the purple laser light source 53 are simultaneously turned on for imaging for a narrow band light image. The obtained normal image and narrow band light image are repeatedly displayed in the respective display areas.

  Further, FIG. 17 shows a display screen of a so-called P in P (Picture in Picture) function in which a narrow-band light image in a desired range is overlaid and displayed on a normal image at the same time. The display range of the narrow band light image can be set to an arbitrary position and an arbitrary size in the normal image by an instruction from the input unit 17 (see FIGS. 1 and 2). Then, within the display range of the narrow band light image, an image at the same position as the display position of the subject in the normal image is displayed. This makes it easier to perform comparison observation at the same position. The above display pattern is an example, and it goes without saying that a display mode in which a normal image is embedded in a narrow band optical image may be used, and other arbitrary combined display may be performed.

Next, setting of the light quantity ratio of the blue laser light and the purple laser light will be described.
In the above description, it is assumed that the light source control unit 55 can arbitrarily set the light amount ratio of the emitted light from the blue laser light source 51 and the violet laser light source 53 shown in FIG. 2 according to an instruction from the input unit 17. Here, a case will be described in which a plurality of types of light quantity ratios are registered in advance and one of the light quantity ratios is designated from the input unit 17.

  For example, in endoscopic observation of a blood vessel image, the preference of the light amount ratio of the blue laser light and the violet laser light may differ for each operator of the endoscope. For example, the operator A preferably feels an observation image in which the light quantity ratio of the violet laser light λa and the blue laser light λb is 60:40, and the operator B feels the light quantity ratio of 75:25 is preferable. Sometimes. In that case, as shown in FIG. 18, the light quantity ratio information in which the operator name, which is the key information, and the light quantity ratio desired by the operator are associated with each other is stored in the storage unit 83 (see FIG. 2) as a light quantity ratio table. Register in advance. When the information corresponding to the operator's name is input from the input unit 17, the control unit 67 refers to the light amount ratio table of the storage unit 83 and automatically sets the desired light amount ratio. Accordingly, the light amount ratio can be set according to the preference of the endoscope operator.

  Further, since the optical characteristics may differ depending on the individual endoscope, the individual identification information for identifying the individual endoscope may be used as the key information instead of the operator name used as the key information. In that case, the information of the light quantity ratio corresponding to this is registered in advance as a light quantity ratio table by using the number, model name, etc. given to each endoscope. As a result, it is possible to set the optimum light amount ratio according to the type and characteristics of each endoscope.

  Further, a plurality of arbitrary light amount ratios may be preset so that the operator can freely select them by a simple operation. For example, as shown in the display example of the display unit 15 in FIG. 19, the preset light intensity ratios are displayed as a “selection button” 87 of GUI (Graphical User Interface), and the operator or the assistant displays the display unit. 15 (see FIGS. 1 and 2) is operated so that the user can freely select by operating the input unit 17. Further, if the display unit 15 is a touch panel, the operator can quickly and intuitively perform the switch operation by directly touching the selection button 87 on the display unit 15 that the operator is gazing at during observation. Further, the operator can compare the observed images that change due to the change of the light amount ratio without taking his eyes off, and can more surely recognize the subtle image change.

  Further, the switching of the light amount ratio is not limited to the switching from the display pattern on the display unit 15, and the switch 89 provided in the operation unit 23 of the endoscope 11 shown in FIG. 1 may be operated as a switching switch. By providing the switch 89 on the operation unit 23, the operator can quickly and easily change the light amount ratio without releasing the hand from the endoscope 11, and the operability of the endoscope is improved.

  As the switch 89, various switches such as a toggle switch, a push switch, a slide switch, and a rotary switch can be used, and as shown in FIG. 20, each time the pressing operation is performed or the contact position of the multi-contact switch is changed, Different light quantity ratios preset in advance are sequentially set. For example, normal light observation for observing white light by the blue laser light source 51 and phosphor 57 in FIG. 2 and narrow band light observation A, B in which narrow band light from the violet laser light source 53 is superimposed on white light at a predetermined ratio. , C,... Or narrow-band light observation of only narrow-band light, the observation light modes of plural kinds of light quantity ratios can be sequentially selected.

  If the switch operation is repeated such as pressing operation, it is not necessary to visually confirm the switch 89, and the switch operation can be performed while gazing at the display unit 15. This makes it possible to easily switch to illumination light suitable for diagnosis. The switch 89 for switching the light amount ratio is not limited to switching the preset light amount ratio, and may be a volume switch or a slide switch for continuously changing the light amount ratio. In that case, it becomes easy to optimally adjust the light amount ratio according to the observation target. Further, by continuously changing the light amount ratio by the switch operation, it is possible to observe a continuous change in the observation image, and it is possible to more accurately grasp the blood vessel structure.

Next, the correction of the tint change of the observed image caused by the change of the light amount ratio will be described.
Image signals R, G, B are input to the image processing unit 65 shown in FIG. 4, and the brightness of these image signals R, G, B is normalized by the brightness calculation unit 65a, and Rnorm, Gnorm, Bnorm. Is converted to image data. The normalized image data Rnorm, Gnorm, and Bnorm are corrected by the color matching unit 65b to a color tone according to the light amount ratio. That is, the color matching unit 65b obtains the image data Radj, Gadj, Badj after the color tone correction by the calculation shown in the equation (1).

Here, k _R , k _G , and k _B are color conversion coefficients of each color, and are determined according to the light amount ratio set at the time of image capturing. FIG. 21 shows a color conversion coefficient table that defines the color conversion coefficient of each color corresponding to the light quantity ratio. The color conversion coefficients k _R , k _G , and k _B are set as R00 to R100, G00 to G100, and B00 to B100 corresponding to the respective light amount ratios, and are stored in the storage unit 83 (see FIG. 2). There is. By substituting the color conversion coefficient corresponding to the light amount ratio used at the time of image capturing into the expression (1), the image data Radj, Gadj, Badj whose color tone has been corrected can be obtained.

  The color conversion coefficient is not limited to being represented as the table shown in FIG. 21, but may be represented by a mathematical expression, or only the representative points may be digitized and other points may be obtained by interpolation calculation. In that case, the amount of information stored in the storage unit 83 can be reduced.

  According to the endoscopic device 100 described above, the violet laser light (and the blue laser light), that is, the illumination light in the short wavelength band particularly suitable for blood vessel observation is used to image the fine blood vessels on the surface layer of the biological tissue. It is possible to emphasize and observe, and it becomes easy to observe the fine structure of blood vessels. Further, since the light amount ratio of the emitted light of the violet laser light and the blue laser light (white light) can be continuously changed, it is possible to easily observe the blood vessel structure changing in the depth direction from the surface layer of the biological tissue, and The blood vessel structure of the surface layer can be clearly understood. Therefore, when observing the living tissue with white light or special light, desired tissue information of the living tissue can be acquired in a clearer state suitable for diagnosis, and the endoscopic diagnosis can be smoothly performed.

  When the endoscope device 100 is configured as a so-called magnifying endoscope including an imaging optical system capable of magnifying and observing an observed region, a microvessel and a microscopic pattern of a mucous membrane on a surface layer of a biological tissue are formed. It is possible to improve the endoscopic diagnosis by increasing the separability of In other words, by magnifying observation, it is possible to confirm the presence of abnormalities such as unequal diameters of microvessels, nonuniform shape, dilation, abnormalities such as meandering, and abnormalities such as disappearance of microscopic patterns of mucous membranes and irregular microminiaturization. It is possible to provide useful information such as diagnosis of.

Next, another configuration example of the endoscope device will be described.
First, an endoscopic device for obtaining the oxygen concentration distribution of blood in an observed image by utilizing the difference in absorption characteristics between hemoglobin and oxyhemoglobin will be described.
FIG. 22 shows absorption spectra of hemoglobin Hb having a low oxygen concentration and oxygen-saturated oxyhemoglobin HbO ₂ at wavelengths of 450 nm to 700 nm. As the illuminating light for observation, the wavelength λ1 at the isosbestic point at which the hemoglobin Hb and the oxyhemoglobin HbO ₂ have equal absorption, and the wavelength λ2 at which the two absorptions are different are selected, and the observation image by the illuminating light of the wavelength λ1 is selected. And the brightness Ab2 of the observed image by the illumination light of wavelength λ2.

  The ratio of the brightness Ab1 and Ab2 of these images serves as an index representing the oxygen concentration in blood, and the change in the metabolic state of the living tissue can be monitored. It is generally said that the cancer area has a low oxygen concentration, and the oxygen concentration is useful information for endoscopic diagnosis.

  As a configuration of the endoscope device for obtaining the above oxygen concentration distribution, as shown in FIG. 23 showing a configuration example of the light source device 41 and the endoscope 11, the endoscope device 200 includes a plurality of light sources in the light source device 41. Is added. Here, for example, a blue-green laser light from a blue-green laser light source 91 having a center wavelength of 515 nm is used as the illumination light at the equal absorption point, and a red laser from a red laser light source 93 having a center wavelength of 630 nm is used as the illumination light having a different absorption. Use light. Of course, when the measurement of the oxygen concentration distribution is the main purpose, the violet laser light source 53 can be omitted. The same reference numerals are given to the same members as those in FIG. 2, and the description thereof will be omitted.

It is preferable that the optical fibers 45A, 45B, 45C, and 45D having the above-mentioned configuration are selected and used in accordance with the wavelengths to be used. The core of the optical fiber has a wavelength dependence in which the transmission loss changes depending on whether the hydroxyl group (OH ⁻ ) concentration is high or low, and at a specific wavelength in the infrared region, the absorptivity is different from that in the visible region. Therefore, when the wavelength of the light source is 650 nm or less, the core optical fiber having a high hydroxyl group concentration is used, and when the wavelength exceeds 650 nm, the core optical fiber having a low hydroxyl group concentration is used.

In order to obtain the oxygen concentration distribution, first, the observed region is imaged by using the blue-green laser light from the blue-green laser light source 91 as illumination light, and then the red laser light from the red laser light source 93 is used as illumination light. Image. At the time of image pickup, the emitted light amounts of the light sources 91 and 93 are adjusted so that the average brightness value of the observed image data and the like become constant. Then, the oxygen concentration index Oindx is calculated for each pixel from the obtained brightnesses Ab1 and Ab2 of each observed image by the equation (2).
Oindx=k·(Ab2/Ab1) (2)
However, k is a coefficient.

  As a result, a distribution image of the oxygen concentration index Oindx is obtained, and the distribution state of the oxygen concentration in the observation image can be grasped.

  Further, the blue-green laser light source 91 and the red laser light source 93, like the blue laser light source 51 and the violet laser light source 53, can individually change the light amount of the emitted light by the light source control unit 55, and the contents of the observation target and the technique. The light amount ratio of each outgoing light is adjusted according to the above. Then, the laser light sources 91 and 93 may each emit light within one frame of the image pickup signal, and the light amount ratio thereof may be appropriately adjusted. The blue-green laser light is suitable for observing fine blood vessels and redness of living tissue, and the red laser light is suitable for observing deep blood vessels of living tissue. Therefore, by changing the light amount ratio of the emitted light of each of these laser lights, information from different regions in the depth direction and information from different targets can be displayed with image enhancement in the same manner as described above.

  Even if the light sources are simultaneously emitted within one frame of the image pickup signal, the light components from the blue-green laser light source 91 and the red laser light source 93 are obtained from the R, G, and B image signals output from the image pickup device 21. The light component or the amount of excitation light can be separately detected.

  In this way, the light quantity ratio of the blue-green laser light to the white light, the light quantity ratio of the red laser light to the white light, or the light quantity ratio of the blue-green laser light and the red laser light is changed arbitrarily and continuously. By making it possible, the visibility of a desired observation target can be enhanced and displayed. Then, by increasing the number of illumination light types of the endoscope and making it multifunctional, even when an unexpected observation need arises at the time of endoscopic diagnosis, the endoscope is quickly removed without being removed from the subject. It is possible to perform observation with appropriate illumination light according to the observation target. Instead of generating the white light by the blue laser light and the excitation light emitted from the phosphor, a white light source such as a halogen lamp may be used. In that case, the light quantity of the blue laser light and the light quantity of the white light can be individually controlled, and the light quantity ratio can be adjusted more finely.

Next, an endoscope device in which the optical path from the light source device 41 to the endoscope 11 is composed of one optical fiber 45 will be described.
FIG. 24 shows a configuration example of the light source device 41 and the endoscope 11. The endoscope device 300 is configured such that the blue laser light from the blue laser light source 51 with a center wavelength of 445 nm is introduced in the optical fiber 45A through a condenser lens (not shown) on the way to the optical fiber 45A. A dichroic prism 95 is provided as an optical coupling means for joining the violet laser light from 53.

  The fluorescent substance 97 arranged on the light emission side of the optical fiber 45A absorbs a part of the blue laser light from the blue laser light source 51, excites and emits green to yellow light, and combines with the blue laser light that is not absorbed and transmitted. Has the property of transmitting white light while absorbing almost no violet laser light from the violet laser light source 53. For this reason, the fluorescent substance 97 emits light with high efficiency by the blue laser light and forms a white light together with the blue laser light. And the selected materials are used.

  In the wavelength conversion by the phosphor 97, there is a wavelength conversion loss (Stokes loss) such as heat generation that is generated in principle. Therefore, it is known that selecting an excitation wavelength having a long emission wavelength has a higher luminous efficiency of the phosphor and is advantageous in suppressing heat generation of the phosphor. Therefore, in this configuration example, white light is generated by the laser light on the long wavelength side to improve the light emission efficiency.

  An example of the emission spectrum of the illumination light by the light source device 41 and the phosphor 97 shown in FIG. 24 is shown in FIG. As shown in FIG. 25, the excitation light emission amount of the phosphor 97 by the violet laser light is a fraction of the excitation light emission amount by the blue laser light (at least 1/3, preferably 1/5, and more preferably Is preferably 1/10 or less).

  As described above, according to this configuration, since the optical paths of the blue laser light and the violet laser light are integrated by the dichroic prism 95, the light source device 41 to the phosphor 97 are guided by one optical fiber 45A, and the illumination light is used. Since the emission port of is accommodated in one place of the phosphor 97, the space efficiency can be increased and the diameter of the endoscope insertion portion can be reduced.

  Even when other laser light sources are provided in addition to the blue laser light source 51 and the violet laser light source 53, the optical paths may be similarly integrated via the optical coupling means such as a dichroic prism. Also for the fluorescent substance 97, a fluorescent substance that is not excited or is difficult to be excited to the wavelength of another laser light source may be used.

Here, as a specific material of the phosphor 97 in this configuration example, for example, as described in JP-A-2006-2115, lead (Pb) is contained as an additional element and digallium calcium tetrasulfide (CaGa ₂ S ₄ ) as a matrix, a crystalline solid fluorescent material, or crystalline solid fluorescence containing lead (Pb) and cerium (Ce) as additional elements and having 2 gallium calcium tetrasulfide (CaGa ₂ S ₄ ) as a matrix. Materials can be used. According to this phosphor material, it is possible to obtain fluorescence in a substantially visible range of about 460 nm to about 660 nm, and the color rendering property under white light illumination is improved.

In addition, in addition to this, LiTbW ₂ O ₈ which is a green phosphor (Kiyoshi Oda, “Phosphor for white LEDs”, IEICE Technical Report ED2005-28, CFM2005-20,SDM2005-28, pp .69-74 (2005-05), etc.), beta-sialon (β-sialon:Eu) blue phosphor (Naoto Hirosaki, Kaiei Gun, Ken Sakuma, “Sialon-based phosphor and white LED using it” Development of the Society of Applied Physics, Vol. 74, No. 11, pp.1449-1452 (2005), or Akira Yamamoto, Faculty of Pionics, Tokyo Institute of Technology, Vol. 76, No. 3, the Applied Physics Society, p. 241 ( 2007)), CaAlSiN ₃ red phosphor, etc. can be used in combination. Beta-sialon is a crystal having a composition of Si _6-z Al ₂ O ₂ N _8-z (z is a solid solution amount) in which β and silicon nitride crystals are solid-solved with aluminum and an acid. The phosphor 97 may be a mixture of these LiTbW ₂ O ₈ and beta sialon, CaAlSiN ₃ , or may be a structure in which these phosphors are layered.

  Each of the above-described phosphors is excited by the blue laser light from the blue laser light source 51, and is not excited and emitted by the violet laser light from the other violet laser light source 53, that is, in the main excitation wavelength band unique to the phosphor. Do not include the emission wavelengths of other light sources.

  In the endoscope apparatus described above, white light is generated by the blue laser light and the excitation and emission light of the phosphors 57 and 97, but the invention is not limited to this. For example, the blue laser light generates green excitation and emission light. It is possible to combine various light sources and phosphors to generate white light, such as a structure using a phosphor and a phosphor that emits red excited emission light by violet laser light.

  As described above, the present invention is not limited to the above-described embodiment, and modifications and applications of those skilled in the art are also intended by the person skilled in the art on the basis of the description in the specification and well-known techniques, and the protection is also included. It is included in the range to obtain.

As described above, the following items are disclosed in this specification.
(1) An endoscope illumination device that obtains illumination light by using emitted light from a plurality of light sources,
A first light source having a semiconductor light emitting element as a light emitting source;
A second light source using a semiconductor light emitting element having an emission wavelength different from that of the first light source as a light source,
A wavelength conversion member that is excited and emitted by light emitted from at least one of the first and second light sources;
A light quantity ratio changing means for changing a light quantity ratio between the light emitted from the first light source and the light emitted from the second light source,
An illuminating device for endoscopes.
According to this endoscope illumination device, since the light amount ratio of the emitted light from the first light source and the second light source can be freely changed, the illumination light having a large emitted light component from the first light source and the second light source can be changed. It is possible to arbitrarily generate illumination light having a large amount of light emitted from the light source and illumination light in the middle thereof. Therefore, it is possible to provide the illumination light suitable for the diagnosis according to the absorption characteristics and the scattering characteristics of the biological tissue, and it is possible to obtain the desired tissue information of the biological tissue in a more clear state.

(2) The illumination device for an endoscope according to (1),
An endoscope illumination device in which the emission wavelength of at least one semiconductor light emitting element of the first light source and the second light source is in the range of 400 nm to 470 nm.
According to this endoscope illumination device, by using the light of the semiconductor light emitting element having a wavelength of 400 nm to 470 nm, the blood vessel in the surface layer part of the biological tissue can be emphasized and observed.

(3) The illumination device for an endoscope according to (1) or (2),
The wavelength conversion member is an endoscope that is a phosphor that generates white light by the emitted light emitted by the wavelength conversion member by excitation light and the emitted light from at least one of the first and second light sources. Lighting equipment.
According to this endoscope illumination device, since white light is generated by the emission of the wavelength conversion member using the light from the semiconductor light emitting element as excitation light, white light with high emission efficiency and high intensity can be obtained. Further, since the semiconductor light emitting element is used as an excitation light source, the intensity of white light can be easily adjusted, and the color temperature and chromaticity of the white light are little changed.

(4) The endoscope illumination device according to any one of (1) to (3),
An illuminating device for an endoscope, further comprising at least one third light source, which uses a semiconductor light emitting element having a light emission wavelength different from that of the first and second light sources as a light source, and which has a different light emission wavelength for each light source.
According to this endoscope illumination device, the wavelength band of the illumination light can be expanded by further including the third light source having a different emission wavelength, and the degree of freedom in selecting the wavelength of the illumination light is improved. This makes it possible to obtain various types of illumination light for image formation, such as a blood vessel-emphasized image with purple light or blue light and an oxygen concentration distribution image with green light and red light.

(5) The endoscope illumination device according to any one of (1) to (4),
Light disposed in the optical path from the first light source to the wavelength conversion member, and at least light emitted from the second light source is guided to the wavelength conversion member together with light emitted from the first light source. An illumination device for an endoscope including a coupling means.
According to this endoscope illumination device, a single optical path is required between the optical coupling means and the wavelength conversion member, and space efficiency is further improved when the endoscope illumination device is incorporated into the endoscope device. The configuration can be improved and simple.

(6) The illumination device for an endoscope according to any one of (2) to (5),
Of the emission wavelengths of the first light source and the second light source, one of them is set on the short wavelength side across the maximum peak wavelength of the absorption wavelength band of hemoglobin, and the other is set on the long wavelength side. Lighting device for endoscopes.
According to this endoscope illumination device, it is possible to capture blood vessel information with high contrast. Further, by reducing the illumination light component in the vicinity of the maximum absorption wavelength of hemoglobin, it is possible to prevent the observed image from becoming dark due to absorption of blood that has exuded to the tissue surface layer.

(7) The endoscope illumination device according to any one of (1) to (6),
The illumination device for an endoscope, wherein the light amount ratio changing unit independently changes the light amount of the emitted light from each of the light sources.
According to this endoscope illumination device, the light amount of the emitted light can be changed for each light source, so that the spectral characteristic of the illumination light finally formed by each light source can be adjusted with a high degree of freedom. ..

(8) The endoscope illumination device according to any one of (1) to (7),
Further comprising input means for inputting light quantity ratio information designating a desired light quantity ratio,
The illumination device for an endoscope, wherein the light quantity ratio changing means determines the light quantity emitted from each of the light sources having the desired light quantity ratio based on the light quantity ratio information input to the input means.
According to this endoscope illumination device, the light quantity ratio is designated by the light quantity ratio information input from the input means, and the quantity of light emitted from the light source that achieves this light quantity ratio is determined. That is, the light amount ratio can be freely changed as specified.

(9) The illumination device for an endoscope according to (8),
Further comprising storage means for storing a light quantity ratio table in which a plurality of kinds of light quantity ratios are associated with key information,
The light ratio information includes the key information,
The illumination device for an endoscope, wherein the light quantity ratio changing unit determines the desired light quantity ratio by referring to the light quantity ratio table based on key information included in the light quantity ratio information input from the input unit.
According to this endoscope illumination device, a desired light quantity ratio is determined by referring to the light quantity ratio table based on the key information included in the light quantity ratio information. That is, by previously registering the light quantity ratio for each key information in the light quantity ratio table, the light quantity ratio corresponding to this key information is automatically determined only by specifying the key information.

(10) The illumination device for an endoscope according to (9),
An endoscope illumination device in which the key information is identification information of an operator of the endoscope device.
According to this endoscope illumination device, it is possible to set an arbitrary light amount ratio for each operator according to the operator's preference of the endoscope.

(11) The illumination device for an endoscope according to (9),
The illumination device for an endoscope, wherein the key information is individual identification information of the endoscope device.
According to this endoscope illumination device, the light amount ratio can be set for each individual endoscope device according to the type and characteristics of each individual endoscope device.

(12) The illumination device for an endoscope according to any one of (9) to (11),
The endoscope illumination device, wherein the input unit is a changeover switch for designating one of a plurality of types of light quantity ratios set in the light quantity ratio table.
According to this endoscope illumination device, a desired light amount ratio can be arbitrarily designated from a plurality of types of light amount ratios by operating the changeover switch, and the light amount ratios can be switched quickly and easily.

(13) An illumination unit that emits illumination light from the endoscope illumination device according to any one of (1) to (12) from a distal end side of an endoscope insertion portion that is inserted into a body cavity.
An image pickup device, which is mounted on the endoscope insertion section, for picking up an observation region illuminated with the illumination light, and which outputs an image signal serving as an observation image,
An endoscopic device provided with.
According to this endoscope device, the observation area is irradiated with the illumination light in which the light quantity ratio of the respective emitted lights from the first light source and the second light source is set to a desired light quantity ratio, and the observation area is illuminated. By capturing an image with the image sensor, an observation image corresponding to the light amount ratio can be obtained. That is, illumination light suitable for diagnosis can be emitted, and desired tissue information of the living tissue can be acquired in a clearer state.

(14) The endoscope apparatus according to (13),
An endoscope apparatus including a light source control unit that causes at least the first light source and the second light source to emit light within one frame of an image signal of the image sensor.
According to this endoscope illumination device, each light source is caused to emit light within one frame of the image signal and an image is picked up by the image pickup device, so that the observation image in which the light emitted from the plurality of light sources is irradiated to the observation region together is displayed. Obtainable.

(15) The endoscope apparatus according to (14),
An endoscope apparatus in which the light source control unit causes at least the first light source and the second light source to emit light at different timings in one frame of an image signal of the image sensor.
According to this endoscope apparatus, it is not necessary to simultaneously emit light from each light source, and the burden on the subject and the power consumption of the apparatus can be suppressed.

(16) The endoscope apparatus according to any one of (13) to (15),
Image processing means for generating a display observation image based on the image signal output from the image sensor,
Display means for displaying information including the display observation image,
An endoscopic device provided with.
According to this endoscopic device, by displaying the information of the image signal from the image pickup device on the display means, the observation image can be easily confirmed and the endoscopic diagnosis can be carried out more smoothly.

(17) The endoscope apparatus according to (16),
First image information captured by the display unit under visible light including emitted light from the first light source and excitation light emitted from the wavelength conversion member;
An endoscope apparatus that simultaneously displays, in the same screen, second image information captured under illumination light that includes light emitted from the second light source in addition to the visible light.
According to this endoscope apparatus, the first image information, which is an observation image when visible light having a wide wavelength band is used as the illumination light, and the second image information, which is an observation image by the illumination light including the narrow band light. And are simultaneously displayed on the same screen of the display means. This facilitates the comparative observation of the normal observation image and the image in which specific information is emphasized.

(18) The endoscope apparatus according to (16) or (17),
First image information captured by the display unit under visible light including emitted light from the first light source and excitation light emitted from the wavelength conversion member;
An endoscopic device that simultaneously displays, in addition to the visible light, image information of either one of the second image information captured under illumination light that includes the light emitted from the second light source, at the same time.
According to this endoscope apparatus, a normal observation image and an image in which specific information is emphasized are displayed in an overlapping manner, which facilitates comparative observation.

(19) The endoscope apparatus according to any one of (13) to (18),
A recording means for recording information including the observation image output from the image processing means,
An endoscope apparatus in which the recording unit records the observation image and the light amount ratio in association with each other.
According to this endoscope apparatus, since the observation image is recorded in association with the light amount ratio set when the observation image is captured, the observation image is recorded according to the light amount ratio when the image is captured. The range of utilization of the observed image can be expanded, for example, by performing image processing using

11 endoscope 13 control device 15 display part 17 input part 19 endoscope insertion part 21 imaging device 23 operation part 35 tip part 37A, 37B irradiation port 41 light source device 43 processor 45A, 45B, 45C, 45D optical fiber 51 blue laser Light source (first light source)
53 Blue laser light source (second light source)
55 light source control unit 57 phosphor (wavelength conversion member)
59 Light deflection/diffusion member 65 Image processing unit 67 Control unit 71 Display screen 73 Endoscopic image region 75 Normal image switching button 77 Narrow band light switching button 79 Adjustment bar 81 Knob 83 Storage unit 85 Adjustment unit 87 Selection button 89 Switch (Selector switch)
91 blue-green laser light source 93 red laser light source 95 dichroic prism 97 phosphor (wavelength conversion member)
100,200,300 Endoscopic device A,B profile B1,B2 Blood vessel

The present invention relates to an endoscope device .

The present invention, when observing a biological tissue by white light or special light, desired tissue information of the biological tissue,
It is an object of the present invention to provide an endoscopic device suitable for diagnosis and which can be acquired in a clearer state.

The present invention has the following configuration.
Illumination light using the emitted light of a plurality of light sources, emitted from the distal end side of the endoscope insertion portion to be inserted into the living body, an endoscope device for outputting an observation image of the observed region ,
A first light source using a semiconductor light emitting element that emits blue light as a light emitting source;
A second light source using a semiconductor light emitting element that emits violet light as a light source;
A dichroic prism that merges the light emitted from the first light source and the light emitted from the second light source;
A light quantity ratio changing means for changing a light quantity ratio between the light emitted from the first light source and the light emitted from the second light source,
An image pickup device that is mounted on the endoscope insertion portion, and that outputs the image signal of the observation image including blood vessel information by imaging the reflected light from the observation region irradiated with the illumination light,
An image processing unit that performs image processing of the image signal to generate output image information,
A display unit that displays an endoscopic observation image based on the output image information .

According to the endoscope apparatus of the present invention, when observing a living tissue using white light or special light of a specific wavelength band, desired tissue information of the living tissue can be acquired in a clearer state suitable for diagnosis.

Next, an endoscope device in which the optical path from the light source device 41 to the endoscope 11 is composed of one optical fiber 45 will be described.
FIG. 24 shows a configuration example of the light source device 41 and the endoscope 11. The endoscope apparatus 300 has a violet laser light source with a central wavelength of 405 nm in the optical path until the blue laser light from the blue laser light source 51 with a central wavelength of 445 nm is introduced into the optical fiber 45A via a condenser lens (not shown). A dichroic prism 95 is provided as an optical coupling means for joining the violet laser light from 53.

Claims (19)

An illumination device for an endoscope, which obtains illumination light using emitted light from a plurality of light sources,
A first light source having a semiconductor light emitting element as a light emitting source;
A second light source using a semiconductor light emitting element having an emission wavelength different from that of the first light source as a light source,
A wavelength conversion member that is excited and emitted by light emitted from at least one of the first and second light sources;
A light quantity ratio changing means for changing a light quantity ratio between the light emitted from the first light source and the light emitted from the second light source,
An illuminating device for endoscopes. The illumination device for an endoscope according to claim 1, wherein
An endoscope illumination device in which the emission wavelength of at least one semiconductor light emitting element of the first light source and the second light source is in the range of 400 nm to 470 nm. The illumination device for an endoscope according to claim 1 or 2, wherein
The wavelength conversion member is an endoscope that is a phosphor that generates white light by the emitted light emitted by the wavelength conversion member by excitation light and the emitted light from at least one of the first and second light sources. Lighting equipment. The illumination device for an endoscope according to any one of claims 1 to 3,
An illuminating device for an endoscope, further comprising at least one third light source, which uses a semiconductor light emitting element having a light emission wavelength different from that of the first and second light sources as a light emission source, the light emission wavelength being different for each light source. The illumination device for an endoscope according to any one of claims 1 to 4,
Light disposed in the optical path from the first light source to the wavelength conversion member, and at least light emitted from the second light source is guided to the wavelength conversion member together with light emitted from the first light source. An illumination device for an endoscope including a coupling means. The illumination device for an endoscope according to any one of claims 2 to 5, wherein:
Of the emission wavelengths of the first light source and the second light source, one of them is set on the short wavelength side across the maximum peak wavelength of the absorption wavelength band of hemoglobin, and the other is set on the long wavelength side. Lighting device for endoscopes. The illumination device for an endoscope according to any one of claims 1 to 6,
The illumination device for an endoscope, wherein the light amount ratio changing unit independently changes the light amount of the emitted light from each of the light sources. The illumination device for an endoscope according to any one of claims 1 to 7,
Further comprising input means for inputting light quantity ratio information designating a desired light quantity ratio,
The illumination device for an endoscope, wherein the light quantity ratio changing means determines the light quantity emitted from each of the light sources having the desired light quantity ratio based on the light quantity ratio information input to the input means. The illumination device for an endoscope according to claim 8, wherein
Further comprising storage means for storing a light quantity ratio table in which a plurality of kinds of light quantity ratios are associated with key information,
The light ratio information includes the key information,
The illumination device for an endoscope, wherein the light quantity ratio changing unit determines the desired light quantity ratio by referring to the light quantity ratio table based on key information included in the light quantity ratio information input from the input unit. The illumination device for an endoscope according to claim 9, wherein
An endoscope illumination device in which the key information is identification information of an operator of the endoscope device. The illumination device for an endoscope according to claim 9, wherein
The illumination device for an endoscope, wherein the key information is individual identification information of the endoscope device. The endoscope illumination device according to any one of claims 9 to 11, wherein:
The endoscope illumination device, wherein the input unit is a changeover switch for designating one of a plurality of types of light quantity ratios set in the light quantity ratio table. An illumination unit that emits illumination light from the endoscope illumination device according to any one of claims 1 to 12 from a distal end side of an endoscope insertion portion that is inserted into a body cavity,
An image pickup device, which is mounted on the endoscope insertion section, for picking up an observation region illuminated with the illumination light, and which outputs an image signal serving as an observation image,
An endoscopic device provided with. The endoscopic device according to claim 13, wherein
An endoscope apparatus including a light source control unit that causes at least the first light source and the second light source to emit light within one frame of an image signal of the image sensor. The endoscopic device according to claim 14, wherein
An endoscope apparatus in which the light source control unit causes at least the first light source and the second light source to emit light at different timings in one frame of an image signal of the image sensor. The endoscope apparatus according to any one of claims 13 to 15, wherein:
Image processing means for generating a display observation image based on the image signal output from the image sensor,
Display means for displaying information including the display observation image,
An endoscopic device provided with. The endoscope apparatus according to claim 16, wherein:
First image information captured by the display unit under visible light including emitted light from the first light source and excitation light emitted from the wavelength conversion member;
An endoscope apparatus that simultaneously displays, in the same screen, second image information captured under illumination light that includes light emitted from the second light source in addition to the visible light. The endoscope apparatus according to claim 16 or 17, wherein
First image information captured by the display unit under visible light including emitted light from the first light source and excitation light emitted from the wavelength conversion member;
An endoscopic device that simultaneously displays, in addition to the visible light, image information of either one of the second image information captured under illumination light that includes the light emitted from the second light source, at the same time. The endoscope apparatus according to any one of claims 13 to 18, wherein:
A recording means for recording information including the observation image output from the image processing means,
An endoscope apparatus in which the recording unit records the observation image and the light amount ratio in association with each other.