JP2016179236A - Endoscope apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: 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 apparatus guides light from a lamp of a light source device to a distal end portion of an endoscope with a light guide installed in an endoscope insertion portion to be inserted into a subject. By radiating from the illumination window at the tip of the mirror, the observation site of the subject is illuminated. White light is usually used for observation of living tissue, but in recent years, light of a specific narrow-band wavelength is used to highlight the state of mucosal tissue, or from pre-administered fluorescent substances. Endoscope apparatuses capable of special light observation for observing autofluorescence are used (Patent Documents 1 and 2). In this type of endoscopic device, by irradiating special tissue to living tissue, for example, new blood vessels generated in the mucosal layer or submucosal layer can be observed, and the fine structure of the mucosal surface that cannot be obtained with normal observation images Is possible.

  In Patent Documents 1 and 2 described above, 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 with a color filter. As a white light source, a laser light source can be used in addition to a xenon lamp. For example, a light emitting device that generates white light by combining a blue laser light source and a phosphor that emits light by using it as excitation light has been proposed. (Patent Document 3).

  However, in the endoscope apparatuses disclosed in Patent Documents 1 and 2, light from a white light source is time-divided by a color filter, and light in different wavelength bands (R, G, B light, etc.) is emitted in a frame sequential manner. It has become. Therefore, in order to obtain a full-color observation image, it is necessary to synthesize a plurality of frames (R, G, B) of captured images, which hinders an increase in the frame rate of the observation image. Further, since the illumination light is generated by absorbing light with the color filter, a decrease in the amount of light is unavoidable, which causes a noise component of the observation image to increase. Although the sensitivity can be increased by lowering the frame rate, in this case, the image is likely to blur.

  On the other hand, in special optical diagnosis, tissue information or the like over the surface layer portion or deep layer portion of a living tissue is an important observation target. For example, in gastrointestinal cancer, tumor blood vessels appear in the surface layer of the mucous membrane from an early stage, and tumor blood vessels are observed to expand, meander, and increase in blood vessel density compared to blood vessels that appear in the normal surface layer. Therefore, the type of tumor can be identified by examining the blood vessel properties. However, in the endoscope apparatus using the color filter described above, it is difficult to limit the transmission wavelength band of the color filter to a specific narrow band, for example, when it is desired to observe tissue information of the surface layer portion of a living tissue, Illumination light limited to a narrow band is disadvantageous in that a sufficient amount of light cannot be obtained and the image quality of the observation image is degraded.

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

  The present invention provides an endoscopic light source device and an endoscopic device that can acquire 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 configuration.
(1) An endoscope illumination device that 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 source;
A second light source that uses 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 excites and emits light by light emitted from at least one of the first and second light sources;
A light amount ratio changing means for changing a light amount ratio between the light emitted from the first light source and the light emitted from the second light source;
Endoscopic illumination device comprising:
(2) an illumination optical system that emits illumination light from the endoscope illumination device from the distal end of the endoscope insertion portion;
An imaging optical system including an imaging element that receives light from the illuminated region irradiated with the illumination light and outputs an image signal;
An endoscopic apparatus comprising:

  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 in a specific wavelength band, desired tissue information of the living tissue is more suitable for diagnosis. It can be acquired in a clear state.

1 is a schematic configuration diagram of an endoscope apparatus using an endoscope light source device for describing an embodiment of the present invention. FIG. It is a block block diagram of the endoscope apparatus shown in FIG. It is a graph which shows the emission spectrum of the light after the wavelength conversion of the laser beam from a violet laser light source, the blue laser beam from a blue laser light source, and a blue laser beam is carried out by fluorescent substance. It is a detailed block diagram of an image processing unit. 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 an enlarged observation image by white light inside the lips observed by the endoscope apparatus. It is an enlarged observation image with a light amount ratio of 50:50 inside the lips observed by an endoscope apparatus. It is an enlarged observation image with a light quantity ratio of 75:25 inside the lips observed by the 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 light emission amount. It is a graph which shows the pulse current superimposed waveform of the applied current. It is explanatory drawing which shows the various drive waveforms (a) by pulse modulation control, (b), (c). It is a graph which shows the example of control which makes the emitted light quantity of a light source alternately maximum. It is a graph which shows the rough relationship between the absorption wavelength band of hemoglobin, and the light emission wavelength of each light source. The display image displayed on the display unit when the endoscope operator moves the endoscope insertion part within the subject, performs observation with a narrow band light at a desired observation position, and moves to the next observation position. It is explanatory drawing which shows this roughly. It is explanatory drawing which shows the example which arrange | positions and displays simultaneously a normal image and a narrow-band light image in each separate area | region within the same screen. It is explanatory drawing which shows the example which overlaps and displays the narrow-band light image of a desired range on a normal image simultaneously. It is explanatory drawing which shows the light quantity ratio table which registered the light quantity ratio with respect to the operator of an 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 switch. It is explanatory drawing which shows the color conversion coefficient table with respect to light quantity ratio. It is a graph which shows the absorption spectrum of hemoglobin Hb with low oxygen concentration and oxygenated hemoglobin HbO ₂ saturated with oxygen. It is a block diagram which shows the structural example of the light source device provided with the several laser light source, 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 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 apparatus using an endoscope light source device for explaining an embodiment of the present invention, and FIG. 2 is a block configuration diagram of the endoscope apparatus shown in FIG. .
An endoscope apparatus 100 illustrated in FIG. 1 includes an endoscope 11 and a control device 13 to which the endoscope 11 is connected. The control device 13 is connected to a display unit 15 that displays image information and an input unit 17 that receives an input operation. The endoscope 11 is an electronic endoscope having an illumination optical system that emits illumination light from the distal end of the endoscope insertion portion 19 and an imaging optical system that includes an imaging element that captures an image of an observation region.

  The endoscope 11 includes an endoscope insertion portion 19 to be inserted into a subject, a bending operation of the distal end of the endoscope insertion portion 19, suction from the distal end of the endoscope insertion portion 19, air supply / water supply, etc. An operation unit 23 that performs the above-described operation, a connector unit 25 that detachably connects the endoscope 11 to the control device 13, and a universal cord unit 27 that connects the operation unit 23 and the connector unit 25. Although not shown, the endoscope 11 is provided with various channels such as a forceps channel for inserting a tissue collection treatment tool and the like, a channel for air supply / water supply, and the like.

  The endoscope insertion portion 19 includes a flexible soft portion 31, a bending portion 33, and a tip portion (hereinafter also referred to as an endoscope tip portion) 35. In the endoscope distal end portion 35, irradiation ports 37A and 37B for irradiating light to the observation region, a CCD (charge coupled device) image sensor or CMOS (Complementary Metal-Oxide Semiconductor) for acquiring image information of the observation region. An image sensor 21 such as an image sensor is disposed. 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 can be bent by a wire operation from the operation portion 23, an operation operation of an actuator, or the like. The bending portion 33 can be bent in an arbitrary direction and an arbitrary angle according to a part of the subject in which the endoscope 11 is used, and the irradiation ports 37A and 37B of the endoscope distal end portion 35 and the image sensor 21. Can be directed to a desired observation site. Although illustration is omitted, 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 ports 37A and 37B of the endoscope distal end portion 35, and a processor 43 that performs image processing on an image signal from the imaging device 21, and the display described above. The unit 15 and the input unit 17 are connected. The processor 43 performs image processing on the imaging signal transmitted from the endoscope 11 based on an instruction from the operation unit 23 or the input unit 17 of the endoscope 11, and generates a display image on the display unit 15. Supply.

  Inside the endoscope 11, optical fibers 45 </ b> A and 45 </ b> B for introducing illumination light from the light source device 41 and a scope cable 47 that connects the imaging 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 through the universal cord unit 27 and the connector unit 25. 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.

  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 emission sources. . Light emission from the semiconductor light emitting elements of these light sources 51 and 53 is individually controlled by the light source control unit 55, and the light quantity 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 is free.

  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, can use a broad area type InGaN laser diode, and use an InGaNAs laser diode or a GaNAs laser diode. You can also In addition, a light-emitting body such as a light-emitting diode may be used as the light source.

  Laser light emitted from each of the light sources 51 and 53 is input to an optical fiber by a condensing lens (not shown), and light is transmitted through the connector portion 26A and the connector 25 on the endoscope 11 side (see FIG. 1). The fibers 45A and 45B are propagated to the endoscope distal end portion 35 (see FIG. 1) of the endoscope 11, respectively. Then, the laser light from the blue laser light source 51 is irradiated to the phosphor 57 which is a wavelength conversion member disposed at the endoscope distal end portion 35, and the laser light from the violet laser light source 53 is irradiated with the light deflection / diffusion member 59. Is irradiated.

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

The phosphor 57 absorbs a part of the blue laser light from the blue laser light source 51 and emits a plurality of kinds of phosphors (for example, YAG phosphor, BAM (BaMgAl ₁₀ O ₁₇ ), etc. that emits green and yellow light. Including phosphors). Thereby, the green to yellow excitation light using the blue laser light from the blue laser light source 51 as excitation light and the blue laser light transmitted without being absorbed by the phosphor 57 are combined to produce white (pseudo white) illumination light. It becomes. If a semiconductor light emitting element is used as an excitation light source as in this configuration example, high intensity white light can be obtained with high luminous efficiency, and the intensity of white light can be easily adjusted. In addition, changes in the color temperature and chromaticity of white light are reduced.

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

  The light deflection / diffusion member 59 may be any material that transmits the laser light from the violet laser light source 53. For example, a light-transmitting resin material or glass is used. Furthermore, the light deflection / diffusion member 59 has a configuration in which a light diffusion layer in which fine irregularities and particles (fillers, etc.) having different refractive indexes are mixed on a resin material or glass surface, or a semi-transparent material. It is good also as a structure using. Thereby, the transmitted light emitted from the light deflection / diffusion member 59 becomes illumination light with a narrow band wavelength in which the amount of light is made uniform within a predetermined irradiation region.

  Note that the phosphor 57 and the light deflecting / diffusing member 59 are caused by speckle generated by the coherence of the laser light, noise superposition, which is an obstacle to imaging, flickering when performing moving image display, etc. Can be prevented. In addition, the phosphor 57 takes into account the difference in refractive index between the phosphor constituting the phosphor and the fixing / solidifying resin serving as the filler, and the particle size of the phosphor itself and the filler is set to the light in the infrared region. In contrast, it is preferable to use a material that has low absorption and high scattering. As a result, the scattering effect is enhanced without reducing the light intensity with respect to light in the red or infrared region, and an optical path changing means such as a concave lens becomes unnecessary, and the optical loss is reduced.

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

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

  That is, in the endoscope apparatus 100, the illumination light is generated by relatively increasing / decreasing the light emission intensities of the profile A and the profile B, so that the illumination light having different characteristics according to the mixing ratio of the profiles A and B is obtained. be able to.

  Returning again to FIG. The illumination light formed by the blue laser light source 51, the phosphor 57, and the violet laser light source 53 as described above is emitted from the distal end portion of the endoscope 11 toward the observation region of the subject. Then, the state of the observation region irradiated with the illumination light is imaged on the imaging element 21 by the imaging lens 61 and imaged.

  An image signal output from the image sensor 21 after imaging 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 endoscopic observation image through the control unit 67. Moreover, it records on the recording device 69 which consists of a memory and a storage apparatus as needed.

  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 recorded together with the information on the light amount ratio at the time of imaging. As a result, it is possible to accurately interpret the recorded endoscopic observation image after endoscopic observation, and to perform appropriate image processing such as standardizing the image according to the light amount ratio. The range of utilization of endoscopic observation images can be expanded. In particular, if the spectral reflectance estimation is performed by artificially increasing the number of bands (R, G, B) based on information on a plurality of light amounts with different spectral ratios, it is possible to separate finer color differences. .

  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 luminance calculation unit 65a. The luminance calculation unit 65a obtains luminance information such as the maximum luminance, the minimum luminance, and the screen average luminance of the image signal, and normalizes the luminance. If the luminance 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 amounts of the light sources 51 and 53 so that the image signal has a desired luminance level. .

  Next, the color matching unit 65b adjusts the normalized image data so that the color tone of the image becomes a desired color tone. For example, when the image signal is composed of R, G, and B color signals, the intensity balance of the R, G, and B color signals is adjusted. In the 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 from the blue laser light source 51 and the emitted light from the violet laser light source 53. The ratio can be arbitrarily changed. Therefore, since the color of the illumination light and the total illuminance may change according to the set light amount ratio, the luminance 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 observation 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 image information for output and outputs it to the control unit 67.

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

By the way, when illumination light is incident on a living tissue, the incident light propagates diffusively in the living tissue, but the absorption and scattering characteristics of the living tissue have wavelength dependence, and the shorter the wavelength, the more the scattering characteristics. There is a tendency to become stronger. That is, the depth of light changes depending on the wavelength of illumination light. On the other hand, blood flowing in blood vessels has a maximum absorption at a wavelength in the vicinity of 400 to 420 nm, and a large contrast can be obtained. For example, blood vessel information from capillaries on the mucosal surface layer is obtained when the illumination light is in the wavelength region λa near the wavelength of 400 nm, and blood vessel information including deeper blood vessels is obtained in the wavelength region λb near the wavelength of 500 nm. Therefore, a light source having a central wavelength of 360 to 800 nm, preferably 365 to 515 nm, and more preferably a central wavelength of 400 nm to 470 nm is used for blood vessel observation on the surface of the living tissue.

  Therefore, as shown in FIG. 6 which shows a schematic display example of the observation image by the endoscope apparatus, the observation image when the illumination light is white light can obtain a relatively deep mucosal blood vessel image, but the mucosal surface layer. The fine capillaries appear blurry. On the other hand, in the observation image when the illumination light is narrowed only with a short wavelength, fine capillaries on the surface of the mucosa can be seen clearly.

  In this configuration example, the light source control unit 55 (see FIG. 2) of the endoscope apparatus 100 can change the light quantity ratio of the emitted light by the blue laser light source 51 having the center wavelength of 445 nm and the violet laser light source 53 having the center wavelength of 405 nm. ing. The change in the light quantity ratio can be performed, for example, by operating a switch 89 provided in the operation unit 23 of the endoscope 11 shown in FIG. 1, and the image can be enhanced so that the capillary blood vessels on the surface of the mucosa can be more easily observed. That is, when there are many blue laser light components by the blue laser light source 51, it becomes illumination light with many white light components by this blue laser light and the excitation light emission by the fluorescent substance 57, and is like the white light observation image of FIG. An observation image is obtained. However, since blue laser light, which is narrow-band light, is mixed in the illumination light, an observation image in which the surface capillary is image-enhanced is obtained.

  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 in 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 purple laser light source 53, that is, by increasing / decreasing the ratio of the purple laser light component to the total illumination light component, Observation with continuous highlighting can be performed.

  Therefore, as the violet laser light component increases, the fine capillaries contained in the thin depth region of the mucosal surface layer are clearly displayed in the observation image, and as the violet laser light component decreases, the mucosal surface layer moves toward the deep layer. Blood vessel information included in a wide depth region is displayed. Thereby, the blood vessel distribution in the depth direction can be displayed 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 blue laser light and blood vessel information on the surface layer obtained by purple laser light are extracted together, and both of them can be compared by image display of these information. It is possible to observe the blood vessel information including the blood vessels on the surface layer, which has not been able to be performed, with improved visibility.

  In addition, at the distal end portion 35 (see FIG. 1) of the electronic endoscope in which the image pickup device 21 is disposed, the heat generation amount is increasing with the increase in power consumption such as the recent increase in the number of pixels and the increase in the frame speed. The light that can be emitted from the tip 35 is also limited. Among these, by changing the light quantity ratio of each light source and suppressing the total light quantity of the illumination light, increasing the necessary light emission depends on, for example, only image processing, resulting in only a noisy image. Problems such as inability to obtain can be solved.

  Here, FIGS. 7A, 7B, and 7C show enlarged images of the inside of the lips observed under the same image processing conditions with the same light amount by the endoscope apparatus 100. FIG. In the figure, an observation image (FIG. 7a) of a blue laser beam having a central wavelength of 445 nm and a white illumination light composed of excitation light emitted from a phosphor, a purple laser beam having a central wavelength of 405 nm, and a blue laser beam having a central wavelength of 445 nm. An observation image (FIG. 7 b) when the light amount ratio is 50:50 and an observation image (FIG. 7 c) when the light amount ratio between the violet laser beam having the central wavelength of 405 nm and the central wavelength 445 nm is 75:25 are shown. Yes. In FIGS. 7b and 7c, illumination light includes excitation light emitted from a phosphor that uses blue laser light having a central wavelength of 445 nm as excitation 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 is increased. In other words, an image in which the capillaries on the surface layer are more emphasized as the proportion of the violet laser light in the illumination light is increased, and the capillaries and fine patterns on the mucosal layer are observed more clearly with increased contrast. Can do. In addition, the light quantity ratio of blue laser light and violet laser light can be freely changed in a stepless manner, so that the three-dimensional blood vessel structure in the surface layer of the mucosa can be inferred from changes in the observed image when the light quantity ratio is continuously changed. It is easy to selectively and clearly project a desired observation target.

  In contrast to the violet light and blue light in the wavelength bands close to each other, the amount of light in the violet region alone can be increased or decreased separately from the light in the blue region, such as in conventional halogen lamps, xenon lamps and color filters. It is difficult to realize with wavelength limiting means. If the emission spectrum is narrowed using wavelength limiting means in the optical path, the original halogen lamp or xenon lamp itself has a small amount of light, and the amount of light in the purple region is further insufficient. In addition, if the half-value width of the emission spectrum is increased in order to increase the amount of light in the purple region, the illumination light cannot be narrowed and image enhancement of a desired blood vessel becomes insufficient.

  And when the amount of illumination light is insufficient, it is generally possible to cope with the shortage of light by increasing the sensitivity of the image sensor or decreasing the frame rate. However, if the sensitivity of the image sensor is increased during imaging, There is a disadvantage that the noise component increases. Further, if the sensitivity is increased by lowering the frame rate, blurring increases, and the observed image becomes difficult to see. In this configuration example, since laser light is used as the light source, high-intensity illumination light is always stably obtained, the observation image can be brightened, and good image quality with low noise can be obtained. In addition, necessary and sufficient illuminance can be obtained even when imaging a distant view.

The above light quantity ratio is changed by the light source control unit 55 shown in FIG. 2 controlling each of the light sources 51 and 53. Next, a method in which the surgeon changes the light quantity ratio while viewing the observation image is shown in FIG. This will be described with reference to FIG.
FIG. 8 shows an example of the display screen 71 of the display unit 15 that displays an observation image obtained by the endoscope apparatus 100. The display screen 71 includes an endoscope image area 73 for displaying an observation image obtained by the endoscope apparatus, a normal image switching button 75 for displaying an observation image obtained 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 is provided, and 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 within the adjustment bar 79 to adjust the light amount ratio so that a desired observation image is obtained.

  The control unit 67 determines the light amount 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 emitted light amounts of the light sources 51 and 53 corresponding to the light amount ratio are obtained. Here, the relationship between the light amount ratio and the emitted light amount of each of the light sources 51 and 53 is stored in the storage unit 83 (see FIG. 2) as a light amount ratio correspondence table, and the control unit 67 corresponds to the light amount ratio of the storage unit 83. The amount of light emitted from each of the light sources 51 and 53 is obtained with reference to the table.

  As described above, when the light amount of each of the light sources 51 and 53 (see FIG. 1) is increased and decreased to set a desired light amount ratio, the control unit 67 is stored in advance based on the light amount ratio set on the display screen 71. The emitted light quantity of each light source 51, 53 is determined with reference to the light quantity ratio correspondence table. Thereby, the light quantity of each light source 51 and 53 can be set so that it may become a desired light quantity ratio by simple operation, without the operator of an endoscope setting directly.

  Further, as shown in FIG. 9, the change of the light amount ratio may be set by using the setting unit 85 for various adjustments of the intensity balance, luminance, and contrast of the R, G, and B color components of the image signal. Or you may use together with adjustment of the knob 81 for light quantity ratio change. According to this, a desired observation target can be displayed with image emphasis arbitrarily such as by expressing it in a pseudo color, and the degree of freedom in changing the display image is improved, thereby making it easier to diagnose.

Next, a method for driving the light sources 51 and 53 by the light source controller 55 will be described.
The light source control unit 55 illustrated 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 light emission amount as shown in FIG. 10, and a desired light emission amount is obtained by controlling the applied current to each of the light sources 51 and 53. . For example, in order to obtain the light emission amount La, the applied current is Ib, the light emission amount Lb based on the relationship R1 is ensured, and the difference ΔL between the light emission amounts Lb and La as fine adjustment allowance is pulse-modulated to the applied current. Obtained by superimposing the 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 a pulse current having the applied current Ib as a bias. By such bias current control and pulse modulation control, a wide dynamic range of light emission amount that can be set can be secured.

  In this case, various drive waveforms can be used for the pulse modulation control. For example, if 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 is used, it is less susceptible to the influence of the dark current of the CCD and CMOS image sensors. The sharpness of the image increases. Further, if a pulse waveform having a period sufficiently fast with respect to the light accumulation time as shown in FIG. 12B is used, the occurrence of flicker related to image display can be reduced, and an image due to laser speckles can be reduced. Noise can also be reduced. Further, as shown in FIG. 12 (c), the ON period of the pulse waveform of FIG. 12 (a) is a pulse waveform having a fast cycle as shown in FIG. 12 (b), and the mixed pulse waveform of (a) and (b). The above effects other than flicker reduction can be enjoyed.

  Further, as shown in FIG. 13, when the light sources 51 and 53 are alternately turned on and controlled so that the light emission amount alternately becomes the maximum, the maximum driving power of the light source device 41 including the light sources 51 and 53 is suppressed. And the burden on the living body as the subject can be reduced. Moreover, the captured image by the illumination light of each light source 51 and 53 can also be acquired separately, In that case, the calculation between images of the acquired image is also attained, and the freedom degree of image processing improves.

FIG. 14 shows a schematic relationship between the absorption wavelength band of hemoglobin and the emission wavelengths of the light sources 51 and 53.
As described above, hemoglobin contained in blood has a maximum absorption at a wavelength in the vicinity of 400 to 420 nm and is included in the absorption wavelength band of hemoglobin or from the light sources 51 and 53 having an emission wavelength close to the absorption wavelength band. Can output the blood vessel information with high contrast. In addition, the light emission wavelengths of the light sources 51 and 53 are set to approximately the same absorption ratio across the hemoglobin absorption wavelength band, so that the strength of the blood vessel information is affected by the light quantity ratio of the light sources 51 and 53. There is nothing. That is, even if the light quantity ratio between the light sources 51 and 53 is changed, the detection sensitivity of the blood vessel image itself is kept constant.

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

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

  Switching from a normal display image by white light observation to a display image by narrow-band light observation, and switching in the opposite direction is performed by one frame of a captured image (R, G, B three-color full color image) of the image sensor 21. Switching is possible in units. For this reason, even when observing while moving the endoscope insertion portion, an image without color misregistration can be displayed in real time without causing the operator to feel uncomfortable. That is, it is possible to provide a good observation image that reliably follows the quick movement of the endoscope, and to improve the operability of the endoscope apparatus.

  In addition, as the display pattern of the observation image on the display unit 15, a normal image at the time of white light observation and a narrow band light image at the time of narrow band light observation can be freely arranged. For example, as shown in FIG. 16, a normal image and a narrowband light image in which specific information is emphasized by arranging a normal image and a narrowband light image in separate areas in the same screen and displaying them simultaneously. It becomes easy to compare and observe the optical image. In this case, the blue laser light source 51 is turned on to capture an image for a normal image using white light, and in the next frame, the blue laser light source 51 and the purple laser light source 53 are turned on at the same time to capture an image. Repeatedly, the obtained normal image and narrowband light image are displayed in the respective display areas.

  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 superimposed on a normal image and displayed simultaneously. The display range of the narrowband light image can be set to an arbitrary position and an arbitrary size in the normal image according to an instruction from the input unit 17 (see FIGS. 1 and 2). An image at the same position as the display position of the subject in the normal image is displayed in the display range of the narrow-band light image. Thereby, comparative observation at the same position becomes easier. Note that the above display pattern is merely an example, and a display form in which a normal image is embedded in a narrow-band light image may be used, and it is needless to say that any other combined display can be performed.

Next, setting of the light amount ratio between the blue laser beam and the violet laser beam will be described.
In the above description, it is assumed that the light source control unit 55 can arbitrarily set the light quantity ratio of the emitted light from the blue laser light source 51 and the violet laser light source 53 shown in FIG. Here, a case where 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 will be described.

  For example, in endoscopic observation of blood vessel images, the preference of the light quantity ratio of blue laser light and violet laser light may differ for each operator of the endoscope. For example, the operator A feels favorable for an observation image in which the light quantity ratio between the violet laser light λa and the blue laser light λb is 60:40, and the operator B feels a light quantity ratio of 75:25. Sometimes. In this case, as shown in FIG. 18, the light quantity ratio information that associates the surgeon name as key information with the preferred light quantity ratio of the surgeon is stored in the storage unit 83 (see FIG. 2) or the like as a light quantity ratio table. Register in advance. Then, when information corresponding to the operator name is input from the input unit 17, the control unit 67 automatically sets a desired light amount ratio with reference to the light amount ratio table of the storage unit 83. Thereby, it can set to the light quantity ratio according to the operator's preference of an endoscope.

  Since the optical characteristics may vary depending on the individual of the endoscope, individual identification information for identifying the individual of the endoscope may be used as the key information instead of the operator name used as the key information. In that case, information on the light quantity ratio corresponding to the number, model name, etc. given to each individual endoscope is registered in advance as a light quantity ratio table. Thereby, the optimal light quantity ratio can be set according to the type and characteristics of each endoscope.

  Furthermore, it is good also as a structure which can preset arbitrary arbitrary several types of light quantity ratios, and an operator can select freely by simple operation. For example, as shown in a display example by the display unit 15 in FIG. 19, a plurality of preset light quantity ratios are displayed as “selection buttons” 87 of GUI (Graphical User Interface), and an operator or assistant can display the display unit. 15 (see FIGS. 1 and 2), the user can select freely by operating the input unit 17. If the display unit 15 is a touch panel, the switch operation can be performed more intuitively and quickly by directly touching the selection button 87 on the display unit 15 that the operator is gazing at. In addition, the operator can compare the observation images that change due to the change in the light amount ratio without taking his eyes off, and can recognize a subtle image change more reliably.

  Further, the switching of the light quantity ratio is not limited to the display pattern on the display unit 15, and the switch 89 provided on the operation unit 23 of the endoscope 11 illustrated in FIG. 1 may be operated as a changeover switch. By providing the switch 89 in the operation unit 23, the light quantity ratio can be changed quickly and easily without the operator removing his / her 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. As shown in FIG. 20, each time a pressing operation is performed, or depending on the contact position of the multi-contact switch, Different light quantity ratios preset in advance are sequentially set. For example, normal light observation with white light by the blue laser light source 51 and phosphor 57 in FIG. 2 and narrow band light observations A and B in which narrow band light from a violet laser light source 53 is superimposed on white light at a predetermined ratio. , C,..., Or observation light modes with a plurality of light intensity ratios such as narrow-band light observation using only narrow-band light.

  If the switch operation is repeated such as a pressing operation, it is not necessary to visually check the switch 89, and the switch operation can be performed while gazing at the display unit 15. Thereby, it can switch easily to the illumination light suitable for a diagnosis. Note that 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 this 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, correction of the color change of the observation image that occurs with the change in the light amount ratio will be described.
Image signals R, G, and B are input to the image processing unit 65 shown in FIG. 4, and the luminance calculation unit 65a normalizes the luminance of the image signals R, G, and B, and Rnorm, Gnorm, and Bnorm. Converted to image data. The normalized image data Rnorm, Gnorm, and Bnorm are corrected to the color tone according to the light amount ratio by the color matching unit 65b. That is, the color matching unit 65b obtains the image data Radj, Gadj, and Badj after color tone correction by calculation as shown in the equation (1).

Here, k _R , k _G , and k _B are color conversion coefficients of the respective colors, and are determined according to the light amount ratio set at the time of imaging. FIG. 21 shows a color conversion coefficient table in which the color conversion coefficients of the respective colors corresponding to the light quantity ratio are determined. 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 quantity ratios, and are stored in the storage unit 83 (see FIG. 2). Yes. By substituting the color conversion coefficient corresponding to the light amount ratio used at the time of imaging into the equation (1), the color-corrected image data Radj, Gadj, and Badj are obtained.

  This color conversion coefficient is not limited to the table shown in FIG. 21, but may be expressed as a mathematical expression. Alternatively, only representative points may be converted into numerical values and other points may be obtained by interpolation. In that case, the amount of information stored in the storage unit 83 can be reduced.

  According to the endoscope apparatus 100 described above, a violet laser beam (and a blue laser beam), that is, illumination light having a short wavelength band particularly suitable for blood vessel observation is used to image a fine blood vessel on the surface of a living tissue. It can be observed with emphasis, and observation of the fine structure of the blood vessel becomes easy. And since the light quantity ratio of the emitted light of the violet laser beam and the blue laser beam (white light) can be continuously changed, it is possible to easily observe the blood vessel structure that changes in the depth direction from the surface of the living tissue. The blood vessel structure in the surface layer can be clearly understood. Therefore, when observing a 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 endoscopic diagnosis can be performed smoothly.

  When the endoscope apparatus 100 is configured as a so-called magnifying endoscope including an imaging optical system capable of magnifying and observing an observation region, the microvessel and the fine pattern of the mucous membrane on the surface of the living tissue Therefore, it becomes possible to perform more advanced endoscopic diagnosis. In other words, enlarged observations can confirm the presence of abnormalities such as irregularities such as caliber, uneven shape, dilation, meandering, loss of mucosal fine pattern, irregularities such as irregular micronization, etc. Can provide useful information such as

Next, another configuration example of the endoscope apparatus will be described.
First, an endoscope apparatus that determines the oxygen concentration distribution of blood in an observation image using the difference in absorption characteristics between hemoglobin and oxygenated hemoglobin will be described.
FIG. 22 shows absorption spectra of hemoglobin Hb having a low oxygen concentration and oxygen-saturated oxygenated hemoglobin HbO ₂ at wavelengths of 450 nm to 700 nm. As the illumination light for observation, the wavelength λ1 at the isosbestic point where the absorption of hemoglobin Hb and oxyhemoglobin HbO ₂ are equal, and the wavelength λ2 where the absorptions of both are different are selected, and the observation image by the illumination light of wavelength λ1 Brightness Ab1 and brightness Ab2 of the observation image by the illumination light of wavelength λ2.

  The ratio of the luminances Ab1 and Ab2 of these images serves as an index representing the oxygen concentration in the blood, and changes in the metabolic state of the living tissue can be monitored. In general, it is said that a cancer region has a low oxygen concentration, and the oxygen concentration is useful information for endoscopic diagnosis.

  As the configuration of the endoscope apparatus for obtaining the oxygen concentration distribution, the endoscope apparatus 200 includes a plurality of light sources in the light source apparatus 41 as shown in FIG. Is added. Here, for example, blue-green laser light from a blue-green laser light source 91 having a center wavelength of 515 nm is used as illumination light at an isosbestic point, and red laser from a red laser light source 93 having a center wavelength of 630 nm is used as illumination light having a different absorption. Use light. Of course, when mainly measuring the oxygen concentration distribution, the purple laser light source 53 can be omitted. In addition, the code | symbol in a figure attaches | subjects the same code | symbol with respect to the same member as FIG. 2, and the description is abbreviate | omitted.

The optical fibers 45A, 45B, 45C, and 45D configured as described above are preferably selected and used in accordance with the wavelengths used. The core of the optical fiber has a wavelength dependency in which the transmission loss changes depending on whether the hydroxyl group (OH ⁻ ) concentration is high or low, and has an absorptance different from the visible wavelength at a specific wavelength in the infrared region. Therefore, when the wavelength of the light source is 650 nm or less, a high-hydroxyl concentration core optical fiber is used, and when it exceeds 650 nm, a low-hydroxyl concentration core optical fiber is used.

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

  Thereby, 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.

  Similarly to the blue laser light source 51 and the violet laser light source 53, the blue-green laser light source 91 and the red laser light source 93 can individually change the amount of emitted light by the light source control unit 55, and the contents of observation objects and procedures The light quantity ratio of each outgoing light is adjusted according to the above. Each of the laser light sources 91 and 93 may emit light within one frame of the imaging signal, and the light amount ratio may be adjusted as appropriate. Blue-green laser light is suitable for observing fine blood vessels and redness of living tissue, and red laser light is suitable for observing deep blood vessels in living tissue. Therefore, by changing the light quantity ratio of the emitted light of each of these laser beams, information from different regions in the depth direction and information from different objects can be displayed with image enhancement as described above.

  Further, even if each light source is caused to emit light simultaneously within one frame of the imaging signal, the light component from the blue-green laser light source 91 and the red laser light source 93 are used from the R, G, and B image signals output from the imaging device 21. The light component or the excitation light amount can be separately detected.

  In this way, the light quantity ratio of blue-green laser light to white light, the light quantity ratio of red laser light to white light, or the light quantity ratio of blue-green laser light and red laser light is arbitrarily and continuously changed. By making it possible, the visibility of a desired observation target can be enhanced and displayed. And by increasing the number of types of endoscope illumination light and making it multifunctional, even if an unexpected need for observation arises during endoscopic diagnosis, the endoscope can be quickly removed without removing it from the subject. Observation with appropriate illumination light according to the observation object becomes possible. In addition, it can also be set as the structure which uses white light sources, such as a halogen lamp, instead of producing | generating white light with blue laser light and the excitation light emission of a fluorescent substance. In that case, the amount of blue laser light and the amount of white light can be individually controlled, and the light amount ratio can be adjusted more finely.

Next, an endoscope apparatus in which an optical path from the light source device 41 to the endoscope 11 is configured by a single 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 includes a violet laser light source having a central wavelength of 405 nm in the middle of an optical path until blue laser light from a blue laser light source 51 having a central wavelength of 445 nm is introduced into an optical fiber 45A through a condenser lens (not shown). A dichroic prism 95 is provided as optical coupling means for merging the violet laser beams from 53.

  The phosphor 97 disposed on the light emitting side of the optical fiber 45A absorbs a part of the blue laser light from the blue laser light source 51, emits light in the green to yellow excitation, and combines with the blue laser light that is transmitted without being absorbed. White light is formed, and the violet laser light from the violet laser light source 53 is transmitted with little absorption. For this reason, the phosphor 97 emits light with high efficiency by blue laser light, and white light is formed together with the blue laser light. Is selected and used.

  The wavelength conversion by the phosphor 97 has a wavelength conversion loss (Stokes loss) such as heat generation that occurs in principle. Therefore, it is known that selecting an excitation wavelength having a long emission wavelength has 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 increase the light emission efficiency.

  An example of an emission spectrum of 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 (at least 1/3, preferably 1/5, more preferably) compared to the excitation light emission amount by the blue laser light. Is preferably 1/10 or less.

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

  In addition, 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 integrated through an optical coupling means such as a dichroic prism. Further, the fluorescent material 97 may be a fluorescent material that is not excited or hardly excited by the wavelength of another laser light source.

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 included as an additive element and digallium calcium tetrasulfide (CaGa _2). Crystalline solid fluorescent material based on S ₄ ), or crystalline solid fluorescent material based on 2 gallium calcium tetrasulfide (CaGa ₂ S ₄ ) containing lead (Pb) and cerium (Ce) as additive elements Material can be used. According to this phosphor material, it is possible to obtain fluorescence that reaches approximately the entire visible range of about 460 nm to about 660 nm, and the color rendering properties during white light illumination are improved.

In addition to this, LiTbW ₂ O ₈ which is a green phosphor (Yoshitoshi Oda, “About phosphor for white LED”, IEICE Technical Report ED2005-28, CFM2005-20, SDM2005-28, pp .69-74 (2005-05), etc.), beta-sialon (Eu) blue phosphor (Naoto Hirosaki, Hoei Gun, Ken Sakuma, “Sialon-based phosphor and white LED using it” Development, "Journal of Applied Physics, Vol. 74, No. 11, pp.1449-1452 (2005), or Akira Yamamoto, Tokyo University of Technology, Department of Pionics, Vol. 76, No. 3, p.241 ( 2007)), a CaAlSiN ₃ red phosphor or the like 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 aluminum and an acid are dissolved in β-type silicon nitride crystal. The phosphor 97 may be a mixture of these LiTbW ₂ O ₈ , beta sialon, and CaAlSiN ₃ , or may have a configuration in which these phosphors are stacked in layers.

  Each phosphor illustrated above is excited by the blue laser light from the blue laser light source 51 and does not emit light 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. The emission wavelength of other light sources should not be included.

  In the endoscope apparatus described above, white light is generated by the blue laser light and the excitation light emitted from the phosphors 57 and 97. However, the present invention is not limited to this. For example, green excitation light is generated by the blue laser light. Various light sources and phosphors can be combined to generate white light, such as a configuration using a phosphor and a phosphor that generates red excitation light by violet laser light.

  As described above, the present invention is not limited to the above-described embodiments, and modifications and applications by those skilled in the art based on the description of the specification and well-known techniques are also within the scope of the present invention. It is included in the range to calculate.

As described above, the following items are disclosed in this specification.
(1) An endoscope illumination device that 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 source;
A second light source that uses 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 excites and emits light by light emitted from at least one of the first and second light sources;
A light amount ratio changing means for changing a light amount ratio between the light emitted from the first light source and the light emitted from the second light source;
Endoscopic illumination device comprising:
According to this endoscope illumination device, since the light quantity ratio of the emitted light from the first light source and the second light source can be changed, the illumination light having a large amount of emitted light component from the first light source, and the second It is possible to arbitrarily generate illumination light having a large amount of light emitted from the light source and intermediate illumination light. Therefore, illumination light suitable for diagnosis can be provided according to the absorption characteristics and scattering characteristics of the living tissue, and desired tissue information of the living tissue can be acquired in a clearer state.

(2) The endoscope illumination device according to (1),
An endoscope illumination device in which an emission wavelength of at least one of the first light source and the second light source is in a range of 400 nm to 470 nm.
According to this endoscope illumination device, by using light of a semiconductor light emitting element having a wavelength of 400 nm to 470 nm, it is possible to observe with emphasis on blood vessels in the surface layer portion of a living tissue.

(3) The endoscope illumination device according to (1) or (2),
The wavelength conversion member is an endoscope that is a phosphor that generates white light by light emitted from the wavelength conversion member by excitation light and light emitted from at least one of the first and second light sources. Lighting equipment.
According to this endoscope illuminating device, white light is generated by the light emission of the wavelength conversion member using the light from the semiconductor light emitting element as the excitation light, so that high intensity white light can be obtained with high luminous efficiency. 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 change in the color temperature and chromaticity of the white light is small.

(4) The endoscope illumination device according to any one of (1) to (3),
An endoscope illuminating apparatus, further comprising at least one third light source having a light emitting source of a semiconductor light emitting element having a light emitting wavelength different from that of the first and second light sources, with a different light emitting wavelength for each light source.
According to the endoscope illumination device, by further including the third light source having a different emission wavelength, the wavelength band of the illumination light can be expanded, and the degree of freedom in selecting the wavelength of the illumination light is improved. Thereby, illumination light for various image formations, such as a blood vessel emphasis image by purple light and blue light, and a distribution image of oxygen concentration by green light and red light, can be obtained.

(5) The endoscope illumination device according to any one of (1) to (4),
Light that is disposed in the optical path from the first light source to the wavelength conversion member and guides the emitted light from at least the second light source to the wavelength conversion member together with the emitted light from the first light source. Endoscopic illumination device including coupling means.
According to this endoscope illuminating device, a single optical path is sufficient from the optical coupling means to the wavelength conversion member, and space efficiency is further improved when the endoscope illuminating device is incorporated into the endoscope device. A simple and enhanced configuration can be achieved.

(6) The endoscope illumination device according to any one of (2) to (5),
Among the emission wavelengths of the first light source and the second light source, either one 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. Endoscopic lighting device.
According to the endoscope illumination device, blood vessel information can be captured 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 observation image from becoming dark due to absorption of blood that has exuded into the tissue surface layer.

(7) The endoscope illumination device according to any one of (1) to (6),
An endoscope illumination apparatus, wherein the light amount ratio changing means changes the light amount of the emitted light from each light source independently.
According to this endoscope illumination device, the spectral characteristic of illumination light finally formed by each light source light can be adjusted with a high degree of freedom by making the amount of emitted light freely changeable for each light source. .

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

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

(10) The endoscope illumination device according to (9),
An endoscope illumination apparatus, wherein the key information is identification information of an operator of the endoscope apparatus.
According to this endoscope illumination device, an arbitrary light amount ratio can be set for each operator according to the preference of the operator of the endoscope.

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

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

(13) Illumination means for emitting illumination light from the endoscope illumination device according to any one of (1) to (12) from the distal end side of the endoscope insertion portion inserted into the body cavity;
An image pickup device for picking up an image of the observation region irradiated with the illumination light is mounted on the endoscope insertion portion, and an image pickup means for outputting an image signal serving as an observation image;
An endoscopic apparatus comprising:
According to this endoscope apparatus, the observation region is irradiated with illumination light in which the light amount ratio of each light emitted from the first light source and the second light source is set to a desired light amount ratio. By taking an image with the imaging element, an observation image corresponding to the light quantity ratio is obtained. That is, illumination light suitable for diagnosis can be irradiated, and desired tissue information of a living tissue can be acquired in a clearer state.

(14) The endoscope apparatus according to (13),
An endoscope apparatus comprising light source control means for causing 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, an observation image in which light emitted from a plurality of light sources is irradiated onto an observation region is obtained by causing each light source to emit light within one frame of an image signal and capturing an image with an imaging device. Can be obtained.

(15) The endoscope apparatus according to (14),
An endoscope apparatus in which the light source control means causes at least the first light source and the second light source to emit light at different timings within 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 an observation image for display based on an image signal output from the image sensor;
Display means for displaying information including the display observation image;
An endoscopic apparatus comprising:
According to this endoscope apparatus, by displaying the information of the image signal from the image sensor on the display means, the observation image can be easily confirmed, and the endoscopic diagnosis can be performed more smoothly.

(17) The endoscope device according to (16),
The display means, first image information imaged under visible light including light emitted 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 picked up under illumination light including light emitted from the second light source in addition to the visible light.
According to this endoscope apparatus, the first image information that is an observation image when visible light having a wide wavelength band is used as illumination light, and the second image information that is an observation image using illumination light including narrow-band light. Are simultaneously displayed on the same screen of the display means. This makes it easy to compare and observe a normal observation image and an image in which specific information is emphasized.

(18) The endoscope apparatus according to (16) or (17),
The display means, first image information imaged under visible light including light emitted from the first light source and excitation light emitted from the wavelength conversion member;
An endoscope apparatus that displays any one piece of image information of second image information picked up under illumination light including light emitted from the second light source in addition to the visible light so as to overlap each other and display simultaneously.
According to this endoscope apparatus, a normal observation image and an image in which specific information is emphasized are displayed in a superimposed manner, and it becomes easy to perform comparative observation.

(19) The endoscope apparatus according to any one of (13) to (18),
A recording unit for recording information including an observation image output from the image processing unit;
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 relation to the light amount ratio set when the observation image is captured, the observation image is recorded in accordance with the light amount ratio at the time of imaging. The range of use of the observation image can be expanded by processing the image.

DESCRIPTION OF SYMBOLS 11 Endoscope 13 Control apparatus 15 Display part 17 Input part 19 Endoscope insertion part 21 Image pick-up element 23 Operation part 35 Tip part 37A, 37B Irradiation port 41 Light source apparatus 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 controller 57 Phosphor (wavelength conversion member)
59 Light deflection / diffusion member 65 Image processing unit 67 Control unit 71 Display screen 73 Endoscopic image area 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 Endoscope A, B Profile B1, B2 Blood vessel

The present invention relates to an endoscope apparatus .

The present invention, when observing a biological tissue with white light or special light, the desired tissue information of the biological tissue,
An object of the present invention is to provide an endoscope apparatus that can be acquired in a clearer state suitable for diagnosis.

The present invention has the following configuration.
An endoscope having an endoscope insertion portion and an operation portion is provided, and illumination light using emitted light from a plurality of light sources is emitted from the distal end side of the endoscope insertion portion, and an observation image of the observation region is displayed. An endoscope apparatus for outputting ,
A first light source having a semiconductor light emitting element emitting blue light as a light source;
A second light source having a semiconductor light emitting element emitting violet light as a light source;
A wavelength conversion member that generates white light that combines the emitted light that is excited and emitted by absorbing a part of the emitted light from the first light source, and the blue light that is transmitted without being absorbed ;
The light amount ratio between the light emitted from the first light source and the light emitted from the second light source is sequentially set to a different ratio preset in each pressing operation. Light intensity ratio setting means;
An imaging device mounted on the endoscope insertion unit and imaging reflected light from an observation region irradiated with the illumination light and outputting an image signal of an observation image including blood vessel information; and
The light amount ratio setting means includes an observation image captured by the image sensor in a thin depth region of a mucous membrane surface layer of a biological tissue as the emitted light component from the second light source increases with respect to all illumination light components. An image in which blood vessel information is emphasized, and an image in which blood vessel information included in a wide depth region from the mucosal surface layer to the deep layer of the living tissue is projected as the emitted light component from the second light source decreases. Endoscopic device.

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

Claims (19)

An endoscope illumination device that 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 source;
A second light source that uses 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 excites and emits light by light emitted from at least one of the first and second light sources;
A light amount ratio changing means for changing a light amount ratio between the light emitted from the first light source and the light emitted from the second light source;
Endoscopic illumination device comprising: The endoscope illumination device according to claim 1,
An endoscope illumination device in which an emission wavelength of at least one of the first light source and the second light source is in a range of 400 nm to 470 nm. An endoscope illumination device according to claim 1 or 2,
The wavelength conversion member is an endoscope that is a phosphor that generates white light by light emitted from the wavelength conversion member by excitation light and light emitted from at least one of the first and second light sources. Lighting equipment. The endoscope illumination device according to any one of claims 1 to 3,
An endoscope illuminating apparatus, further comprising at least one third light source having a light emitting source of a semiconductor light emitting element having a light emitting wavelength different from that of the first and second light sources, with a different light emitting wavelength for each light source. The endoscope illumination device according to any one of claims 1 to 4,
Light that is disposed in the optical path from the first light source to the wavelength conversion member and guides the emitted light from at least the second light source to the wavelength conversion member together with the emitted light from the first light source. Endoscopic illumination device including coupling means. An endoscope illumination device according to any one of claims 2 to 5,
Among the emission wavelengths of the first light source and the second light source, either one 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. Endoscopic lighting device. It is an illuminating device for endoscopes of any one of Claims 1-6,
An endoscope illumination apparatus, wherein the light amount ratio changing means changes the light amount of the emitted light from each light source independently. It is an illuminating device for endoscopes of any one of Claims 1-7,
It further comprises input means for inputting light quantity ratio information for designating a desired light quantity ratio,
The endoscope illumination device, wherein the light amount ratio changing unit determines the emitted light amount of each of the light sources having the desired light amount ratio based on the light amount ratio information input to the input unit. An endoscope illumination device according to claim 8,
A storage means for storing a light quantity ratio table in which a plurality of types of light quantity ratios are associated with key information;
The light quantity ratio information includes the key information,
The endoscope illumination device, wherein the light amount ratio changing unit determines the desired light amount ratio with reference to the light amount ratio table based on key information included in the light amount ratio information input from the input unit. An endoscope illumination device according to claim 9,
An endoscope illumination apparatus, wherein the key information is identification information of an operator of the endoscope apparatus. An endoscope illumination device according to claim 9,
An endoscope illumination apparatus, wherein the key information is individual identification information of the endoscope apparatus. It is an illuminating device for endoscopes of any one of Claims 9-11,
An endoscope illumination apparatus, wherein the input unit is a changeover switch that designates one of a plurality of types of light amount ratios set in the light amount ratio table. Illuminating means for emitting 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 to be inserted into a body cavity;
An image pickup device for picking up an image of the observation region irradiated with the illumination light is mounted on the endoscope insertion portion, and an image pickup means for outputting an image signal serving as an observation image;
An endoscopic apparatus comprising: An endoscope apparatus according to claim 13,
An endoscope apparatus comprising light source control means for causing 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 endoscope apparatus according to claim 14, wherein
An endoscope apparatus in which the light source control means causes at least the first light source and the second light source to emit light at different timings within one frame of an image signal of the image sensor. The endoscope apparatus according to any one of claims 13 to 15,
Image processing means for generating an observation image for display based on an image signal output from the image sensor;
Display means for displaying information including the display observation image;
An endoscopic apparatus comprising: The endoscope apparatus according to claim 16, wherein
The display means, first image information imaged under visible light including light emitted 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 picked up under illumination light including light emitted from the second light source in addition to the visible light. The endoscope apparatus according to claim 16 or 17,
The display means, first image information imaged under visible light including light emitted from the first light source and excitation light emitted from the wavelength conversion member;
An endoscope apparatus that displays any one piece of image information of second image information picked up under illumination light including light emitted from the second light source in addition to the visible light so as to overlap each other and display simultaneously. The endoscope apparatus according to any one of claims 13 to 18,
A recording unit for recording information including an observation image output from the image processing unit;
An endoscope apparatus in which the recording unit records the observation image and the light amount ratio in association with each other.