JP2011224044A - Light source device and endoscope apparatus using the same - Google Patents

Abstract

When generating illumination light using surface-emitting light from a plurality of light emitting elements, the intensity distribution of the illumination light is made uniform with high accuracy.
A light emitting section 75 in which a plurality of light emitting bodies 73 are arranged on a support 71, and a light guide for introducing light from the light emitting section 75 into an incident surface on one end side and emitting illumination light from an exit surface on the other end side. The light source device includes a light member LG, and a light collecting member 77 that is disposed between the light emitting unit 75 and the light guide member LG and collects light from the light emitting unit 75 on an incident surface of the light guide member LG. The condensing member 77 is composed of a plurality of tapered columnar bodies 79 that taper toward the incident surface of the light guide member LG, and the base end portions 79b of the plurality of tapered columnar bodies 79 are respectively connected to the light emitting body 73. A light exit window 89 arranged to face the light emitting surface and binding the tip portions 79a of the plurality of tapered columnar bodies 79 was formed on the side facing the incident surface of the light guide member LG. Further, the light quantity control means 65 controls the emitted light quantity of the plurality of light emitters 73.
[Selection] Figure 3

Description

  The present invention relates to a light source device and an endoscope apparatus using the light source device.

  In general, a xenon lamp is widely used as an illumination light source for medical and industrial endoscope apparatuses. Recently, a light-emitting diode element (LED) having a long light source replacement life, power saving, and small size. ) Has been attracting attention as a light-emitting element that replaces a xenon lamp. For example, as shown in FIG. 18, an endoscope apparatus in which a plurality of LEDs 1 are arranged on a support 2, the emitted light of each LED 1 is collected by a lens 3 and introduced into an optical fiber bundle of a light guide LG. It has been proposed (Patent Document 1).

  However, when surface emitting light is formed by a plurality of light emitting elements, illumination light is affected by the characteristics of the light emitting elements such as the arrangement pattern of each light emitting element on the substrate and the variation in the amount of emitted light, and the optical system characteristics in the middle of the optical path. It is difficult for the intensity distribution to be uniform, which causes luminance unevenness such as shading and shadows in the observed image.

  Further, when light from the light source device side is introduced into the end surface of the light guide LG on the endoscope probe side, light may leak to the end surface of the metal sleeve that covers the outer periphery of the optical fiber bundle due to the aberration of the lens 3. The light guide LG requires a different amount of light depending on the type of endoscope probe, so the bundle diameter is also different. Therefore, the diameter of the metal sleeve is also different for each type of endoscope probe. For example, a light guide LG having a large diameter as shown in FIG. 19A is used for an oral endoscope apparatus or an endoscope for a lower digestive organ, and for example, as shown in FIG. 13B for a nasal endoscope or a bronchoscope. Light guide with a small diameter. Therefore, when the light guides LG having different diameters are connected to the light source device via the connectors, if light from the light source device side is introduced into the light guide LG with a uniform light intensity distribution, the light guide with a small diameter is provided. LG is more likely to irradiate the metal sleeve 4 with leakage light. In particular, the light emitted from the LED 1 arranged on the outer edge side of the support 2 is easily irradiated to the metal sleeve 4.

JP 2000-66115 A

  The present invention has been made in view of the above circumstances, and the light intensity introduced into the light guide member when the surface emission light composed of the plurality of light emitting elements is irradiated to the observation region via the light guide member. It is an object of the present invention to provide a light source device capable of making the intensity distribution of illumination light uniform with high accuracy by making the distribution freely adjustable, and an endoscope apparatus using the same.

The present invention has the following configuration.
(1) A light emitting unit in which a plurality of light emitters are arranged on a support, a light guide member that introduces light from the light emitting unit into an incident surface on one end side and emits illumination light from an exit surface on the other end side; A light condensing member disposed between the light emitting unit and the light guide member, and condensing light from the light emitting unit on an incident surface of the light guide member,
The light condensing member is composed of a plurality of tapered columns that taper toward the incident surface of the light guide member,
Proximal end portions of the plurality of tapered columnar bodies are respectively arranged facing the light emitting surface of the light emitter,
A light exit window that binds the tip ends of the plurality of tapered columnar bodies is formed on a side facing the incident surface of the light guide member;
A light source device further comprising light amount control means for controlling the amount of light emitted from the plurality of light emitters.
(2) the above light source device;
An endoscope that includes: an endoscope that irradiates an observation region with light emitted from the light source device via the light guide member.

  According to the illumination device of the present invention and the endoscope device using the illumination device, the surface emitting light composed of a plurality of light emitting elements is introduced to the observation region via the light guide member. By making it possible to freely adjust the light intensity distribution to be performed, it is possible to obtain illumination light in which the intensity distribution is made uniform with high accuracy.

It is a figure for demonstrating embodiment of this invention, and is a notional block block diagram of an endoscope apparatus. It is an external view as an example of the endoscope apparatus shown in FIG. It is a typical block diagram of an illuminating device. It is explanatory drawing which showed the mode of condensing by one taper-shaped column. (A) is an example of the arrangement of the light condensing member, 4 × 4 white LEDs are arranged vertically and horizontally on the support, the base end portion of the tapered columnar body faces the light emitting surface of each white LED, and the tip portion FIG. 2B is a schematic configuration diagram showing a light exit window by bundling together, and (B) is a partially enlarged view showing the position of the light exit window in an enlarged manner. It is a block diagram at the time of using a concave-shaped support body. It is a block diagram at the time of arrange | positioning the auxiliary light-emitting body which orient | assigned the light emission direction to the light emission window between the adjacent taper-shaped column bodies. It is a schematic sectional drawing of the light emission part by which the fluorescent substance layer was formed on the support body which mounted LED. It is a block diagram at the time of disperse | distributing a fluorescent substance to a taper-shaped column. It is a graph which shows the spectrum of the combination of the emitted light of LED, and a fluorescent substance, and the combination of a laser beam and fluorescent substance. (A) is a block diagram which shows an example which provided the infrared rays absorber as the light emission window of the condensing member which consists of a some taper-shaped column, (B) selectively selects an infrared component in the light emission window of a condensing member. FIG. 6 is a configuration diagram showing an example in which a stub having a multilayer reflective film to be reflected is provided, and FIG. 6C is a configuration diagram showing an example in which a stub having an infrared reflection function is provided in place of the dichroic prism in (B). (A) is explanatory drawing which shows typically the mode of the light introduction to a light guide when the large diameter light guide LG is connected to the light source device, (B) is the lighted support body shown to (A). It is a top view which shows upper LED. (A) is explanatory drawing which shows typically the mode of the light introduction to a light guide when the small diameter light guide LG is connected to the light source device, (B) is on the lighted support body shown to (A). It is a top view which shows this LED. It is the circuit diagram which simplified and showed the connection circuit of the light emission part. (A), (B), (C), (D) is explanatory drawing which shows typically the example of the emitted light pattern in a light-projection window. It is a schematic block diagram which shows the front-end | tip part and connector part of an endoscope. It is a schematic sectional view showing a state where a branched optical fiber is subjected to a skew process. It is explanatory drawing which shows the connection structure of the conventional light source device and an endoscope probe. It is explanatory drawing which shows the connection state (A) of the conventional large diameter light guide, and the connection state (B) of a small diameter light guide.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram for explaining an embodiment of the present invention, and is a conceptual block diagram of an endoscope apparatus. FIG. 2 is an external view as an example of the endoscope apparatus shown in FIG.
As shown in FIGS. 1 and 2, the endoscope apparatus 100 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 includes an illumination optical system that emits illumination light from the distal end of an endoscope insertion portion 19 (see FIG. 2) that is inserted into a subject, and an image sensor 21 that captures an observation region (see FIG. 1). ) Including an imaging optical system.

  The endoscope 11 includes an endoscope insertion unit 19, an operation unit 23 (see FIG. 2) for performing an operation for bending and observing the distal end of the endoscope insertion unit 19, and the endoscope 11. Connector portions 25A and 25B that are detachably connected to the control device 13 are provided. Although not shown, various channels such as a forceps channel for inserting a tissue collection treatment instrument and the like, a channel for air supply / water supply, and the like are provided inside the operation unit 23 and the endoscope insertion unit 19. .

  As shown in FIG. 2, the endoscope insertion portion 19 includes a flexible soft portion 31, a bending portion 33, and a distal end portion (hereinafter also referred to as an endoscope distal end portion) 35. As shown in FIG. 1, the endoscope distal portion 35 has an irradiation port 37 for irradiating light to the observation region, a CCD (Charge Coupled Device) image sensor for acquiring image information of the observation region, and a CMOS (Complementary). An image sensor 21 such as a metal-oxide semiconductor (image sensor) is disposed. An objective lens unit 39 that forms an observation image is disposed on the light receiving surface side of the image sensor 21.

  The bending portion 33 shown in FIG. 2 can be freely bent by a turning operation of the angle knob 41 disposed in the operation portion 23. The bending portion 33 can be bent in an arbitrary direction and an arbitrary angle depending on a part of the subject in which the endoscope 11 is used, and the observation of the irradiation port 37 and the imaging element 21 of the endoscope distal end portion 35. The direction can be directed to the desired observation site.

  In the medical field, different types of endoscopes 11 are prepared depending on the intended use, such as nasal endoscopes, oral endoscopes, endoscopes for lower digestive organs, bronchoscopes, etc. The operator of the endoscope attaches an appropriate endoscope to the control device 13 based on the instructed endoscopic examination order, for example. Each of the endoscopes 11 has a memory (individual information holding means) 43 for storing various types of individual information regarding the type, spectral sensitivity characteristics of the image sensor, and illumination light, and the control device 13 is connected to the endoscope 11. Individual information of the endoscope 11 is read from the memory 43, the type of the endoscope 11 is identified by the control unit 45, and each unit is controlled so that the technique and display are performed under appropriate conditions.

  The control device 13 includes a light source device 47 that generates illumination light to be supplied to the irradiation port 37 of the endoscope distal end portion 35, and a processor 49 that performs image processing on an image signal from the imaging device 21, and includes connector portions 25A and 25B. Via the endoscope 11. In addition, the processor 49 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, generates a display image, and displays the display unit. 15 is supplied.

  An amplifier (hereinafter abbreviated as AMP) 51 and an image sensor driver 53 provided in the processor 49 are connected to the image sensor 21. The AMP 51 amplifies the image signal output from the image sensor 21 with a predetermined gain and outputs the amplified signal to a correlated double sampling / programmable gain amplifier (hereinafter abbreviated as a CDS / PGA circuit) 55.

  The CDS / PGA 55 outputs the imaging signal output from the AMP 51 as R, G, and B image data corresponding to the charge accumulation amount of each light receiving cell of the imaging device 21, and amplifies the image data to perform A / A Output to D converter 57. The A / D converter 57 converts the analog image data output from the CDS / PGA circuit 55 into digital image data. The image processing unit 59 performs various types of image processing on the image data digitized by the A / D converter 57 and outputs an observation image in the body cavity to the display unit 15.

  A timing generator (hereinafter abbreviated as TG) 61 controlled by the control unit 45 is connected to the image sensor driver 53. The image sensor driver 53 controls the read timing of the image signal (charge accumulation amount) of the image sensor 21, the shutter speed of the electronic shutter of the image sensor 21, and the like based on the timing signal (clock pulse) input from the TG 61.

  The light source device 47 includes a light source unit 63 that supplies illumination light to the irradiation port 37 of the endoscope 11, a light source driver 65 as a light amount control unit that controls an emitted light amount of the light source unit 63, and the like. The emitted light from the light source unit 63 is irradiated to the observation area through the irradiation port 37 through the light guide LG made up of a number of optical fiber bundles. In this configuration example, a plurality of LEDs (light emitting diodes) having a central oscillation wavelength of, for example, 450 to 470 nm are used as the light emitting elements of the light source unit 63, and the light is emitted from the LEDs on the light emission surface of the LEDs. A phosphor layer containing a phosphor excited by blue light is disposed.

The phosphors are a plurality of kinds of phosphor materials (for example, YAG-based phosphors or phosphors such as BAM (BaMgAl ₁₀ O ₁₇ )) that absorb a part of the light emitted from the LED and excite and emit green to yellow light. Consists of including. As a result, the green to yellow excitation light that uses blue light as the excitation light and the light emitted from the LED that is transmitted without being absorbed by the phosphor are combined to generate white (pseudo-white) illumination light. The generated white illumination light is guided by the light guide LG and irradiated from the irradiation port 37 to the observation area.

  Here, the white light referred to in the present specification is not limited to the one that strictly includes all wavelength components of visible light, and examples thereof include R (red), G (green), and B (blue) that are reference colors. As long as it includes light in a specific wavelength band, for example, light including a wavelength component from green to red, light including a wavelength component from blue to green, and the like are broadly included.

  In consideration of the refractive index difference between the phosphor constituting the phosphor and the fixing / solidifying resin serving as the filler, the above phosphors have the same particle size with respect to the phosphor and the filler in the infrared region. On the other hand, 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 red or infrared light, and the optical loss can be reduced.

  Further, the control unit 45 and the TG 61 are connected to the light source driver 65. The light source driver 65 is pulse-shaped according to the control of the control unit 45 within the exposure period defined by the readout pulse that controls the readout timing of the imaging signal (accumulated charge) of the solid-state imaging device 42 from the TG 61 and the electronic shutter pulse. The drive current is supplied. That is, the light source driver 65 can irradiate the observation area with arbitrary illumination light in synchronization with the imaging timing of the imaging device 21.

  As described above, the light emitted from each LED (also referred to as a white LED) and the white light generated by the excitation light emitted from the phosphor are emitted from the distal end portion 35 of the endoscope 11 toward the observation region. The state of the observation region irradiated with the illumination light is acquired as a captured image by forming an object image on the image sensor 21 by the objective lens unit 39.

  The image signal of the captured image output from the image sensor 21 after imaging is subjected to signal processing as described above and input to the image processing unit 59. The image processing unit 59 performs various processes such as white balance correction, gamma correction, contour enhancement, and color correction on the captured image signal from the image sensor 21 converted into a digital signal, and endoscopic observation together with various information. The image is output to the display unit 15. If necessary, the endoscope observation image is stored in a storage unit (not shown) including a memory and a storage device.

Next, the light source device of the endoscope apparatus 100 having the above configuration will be described in detail.
FIG. 3 shows a schematic configuration diagram of the lighting device.
The illuminating device 200 includes a light source 63 mounted on the light source device 47 described above, and a light guide LD serving as a light guide member that emits illumination light from the other end side by connecting one end side to the light emission port of the light source unit 63. And have. The light source unit 63 includes a plurality of white LEDs (light emitters) 73 arranged on a support 71, a light emitting unit 75 that emits light upon receiving power supply from the light source driver 65, and the light emitting unit 75 and the light guide LG. It has a condensing member 77 which is arranged between one end side, and condenses the emitted light from light-emitting part 75 on the light entrance surface of light guide LG.

  The light guide LG is a long light guide member having a large number of optical fiber bundles and a sleeve 81 covering the outer periphery of the optical fiber bundle. The light guide LG is inserted by connecting the connector portion 25A to the light source device 47 so that the protective pipe 83 covering the outer periphery of the sleeve 81 is guided by the engagement hole 85, and the glass window 87 at the tip of the light guide LG is inserted. The light source 63 is fixed in a state of facing the light exit window 89.

The sleeve 81 is cylindrical and can be made of, for example, a metal such as stainless steel or copper alloy, ceramics, crystallized glass, resin, etc. In particular, zirconia ceramics (zirconium oxide: ZrO ₂ ) is semi-transmissive to light. Therefore, it is preferable. By forming the sleeve 81 from zirconia ceramics, even if high-intensity light is irradiated to the sleeve end face, the irradiation light can penetrate from the sleeve end face to the inside to expand the light irradiation range. Thereby, it is possible to prevent a local temperature increase from occurring at the end face of the sleeve.

  The light source unit 63 is provided with a heat sink 91, and the heat generated by the light source unit 63 is released to the outside by the air blown from the fan 93.

  The condensing member 77 is an aggregate of a plurality of tapered columnar bodies 79 that taper toward the light guide LG, and one tapered columnar 79 is arranged corresponding to one white LED 73. FIG. 4 shows how light is collected by one tapered column 79. The tapered columnar body 79 is a wedge-shaped columnar body that is made of light-transmitting glass or resin and whose cross-section is reduced toward the front of the optical path. Here, a triangular prism shape that can bundle a plurality of tapered columnar bodies 79 at a higher density is used. However, in addition to this, a cylindrical shape or other polygonal column shape may be used, and a cone shape or a polygonal pyramid shape may be used. Good.

  The tapered column 79 has a distal end 79 a connected to a planar light exit window 89 facing the light incident surface of the light guide LG, and a base end 79 b facing the light emitting surface of the white LED 73. ing. The emitted light from the white LED 73 is guided while being condensed to the tip end portion 79 a while repeating total reflection in the tapered columnar body 79. As a result, most of the light emitted from the light emitter can be incident on the light guide LG as effective light, and the light utilization efficiency can be improved.

  Further, the tapered columnar body 79 is provided with a selective light-transmitting member that restricts transmission of infrared components in the middle of the optical path of at least one of the distal end portion 79a and the proximal end portion 79b. As this selective translucent member, for example, an infrared cut filter which is an infrared absorber can be used. Further, the entire tapered columnar body 79 may be a member having an optical function of selectively removing infrared rays.

  The wavelength of infrared rays that restricts transmission is preferably 650 nm or more. According to this, when a color captured image is acquired by a general image sensor, the wavelength on the longer wavelength side than the R (red) light of the image sensor is present. The light receiving component in the sensitivity range is not superposed on the image data, and color mixing can be prevented.

  In the configuration of the light source unit 63 of this configuration example, 4 × 4 white LEDs 73 are arranged vertically and horizontally on the support 71 as shown in FIG. With the base end 79b of the tapered column 79 facing the light emitting surface of each white LED 73, the base end 79b is fixed with, for example, a transparent adhesive or a fixing jig (not shown). And the front-end | tip part 79a of the some taper-shaped column 79 is bundled, without disturbing the arrangement | sequence, and the light emission window 89 of a micro size is formed. When a part of the light exit window 89 is enlarged, as shown in FIG. 5 (B), the tip end portions 79a of the tapered columnar body 79 are in a bundled state in which they are densely packed. Each of these tip portions 79a constitutes a light exit window 89.

Here, the white LED73 is surface mounted (SMD), directly support chip-on-board type to be mounted on (COB) is used, the size of the emission surface is 0.6 mm ² to 10 mm ² approximately The approximate square shape, preferably about 1 mm ² . The area of the light exit window at the distal end 79a of the tapered columnar body 79 is 1 to 5 mm ^2, and preferably about 2 mm ^2, the longitudinal direction of the length of the tapered columnar body 79 is about 20 mm.

  According to the light source device 100 having the above-described configuration, light emitted from the plurality of white LEDs 73 is introduced into the base end portion 79b of the tapered columnar body 79, and is totally reflected and guided through the tapered columnar body 79 to be the distal end portion 79a. Is emitted as a high-density light flux. Therefore, high-efficiency and high-intensity light is emitted from the light emission window 89 in which the tips 79a of the plurality of tapered columnar bodies 79 are bundled. In this way, the light exit window 89 is optically connected with a large number of tapered columnar bodies 79. When viewed from the light exit side, the light emitting window 89 has numerous mirrors such as kaleidoscopes. Seems to be distributed. Therefore, the emitted light from each light emitter is not scattered outside, but most of the emitted light component is condensed on the light exit window 89 to become a high-density light beam.

  Further, since the tip 79a of each tapered column 79 is bundled while maintaining the arrangement relationship of the white LEDs 73, the light emission pattern according to the arrangement on the support 71 corresponding to the amount of light emitted from each white LED 73. Thus, the light can be condensed on the light exit window 89.

  Here, when the intensity distribution of the light emitted from the light exit window 89 is maximized at the center of the light exit window 89 and the intensity decreases as the distance from the periphery increases, the endoscope connected to the light source device 47 Even if the diameter of the light incident surface of the light guide LG changes (corresponding to the diameter of the glass window 87 shown in FIG. 3) depending on the type of the light guide LG, most of the emitted light is introduced into the light incident surface of the light guide LG. It will not leak.

  By making the intensity distribution of the emitted light from the light exit window 89, the sleeve 81 is irradiated with high-intensity light, the light is reflected and returned to the light source side, and the support 71 of the light-emitting unit 75 or white The light source unit 63 and the light guide LG are not affected by heat, such as raising the temperature of the LED 73 or heating the light guide LG due to heat generated by the light applied to the sleeve 81. . Therefore, even if the endoscope connected to the light source device 47 is a different type of endoscope such as a nasal endoscope, an oral endoscope, a lower digestive endoscope, a bronchoscope, etc. On the other hand, it is possible to reliably irradiate high-intensity illumination light on the light incident surface of the light guide LG, and to prevent irradiation around the sleeve 81 and the like other than the light incident surface.

  The intensity distribution of the emitted light from the light exit window 89 can be freely changed by controlling the amount of light emitted from each white LED 73 in the light emitting unit 75 by the light source driver 65, and can be adjusted by arbitrary tying.

  The support 71 is not limited to a flat plate shape, and may be a concave support 71A as shown in FIG. When the white LED 73 is arranged on the surface of the support 71A having the condensing member 77 formed in a concave shape, the distance from the white LED 73 to the light exit window 89 can be equalized regardless of the arrangement position of the white LED 73, and a tapered column. The overall length of the body 79 can be made shorter. As a result, the emitted light from each white LED 73 reaches the light exit window 89 under the same conditions, and the light quantity difference due to the difference in the arrangement position of the white LED 73 on the support 71 is eliminated. In addition, it is possible to easily bundle the tip portions 79a of the respective tapered columnar bodies 79 while maintaining the arrangement relationship of the white LEDs 73 as they are.

  The relationship between the tapered column 79 and the white LED 73 is that in addition to providing one white LED for one tapered column, as shown in FIG. Between 79A and 79B, the white LED 95 as the light auxiliary light emitter may be arranged with the emission direction directed toward the light emission window 89. In this case, the emitted light from the white LED 95 is emitted from a gap generated when the tip end portions 79a of the tapered columnar body 79 shown in FIG. 5B are bundled, and the amount of light emitted from the light exit window 89 is further increased.

  Further, as shown in FIG. 7, if the tapered columnar body 79A is bonded to the adjacent tapered columnar body 79B via the bonding surface 97, the light from the plurality of white LEDs 73 is emitted from the tip of one tapered columnar body 79A. Can be emitted together. Thereby, the area occupied by the light exit window 89 for one light emitter can be reduced, and the number of tapered column bodies 79 bundled in the light exit window 89 can be increased. Therefore, it is possible to generate illumination light with higher luminance by increasing the number of light emitters that contribute to generation of illumination light.

Next, the other aspect of the light emission part 75 is shown below.
FIG. 8 is a schematic cross-sectional view of a light emitting unit in which a phosphor layer is formed on a support on which LEDs are mounted. In this configuration, a plurality of blue LEDs 73A are arranged on the support 71, and the phosphor layer 101 containing the aforementioned phosphor is formed on the surfaces of the support 71 and the blue LEDs 73A. The phosphor layer 101 is formed by drying and solidifying after applying a liquid in which the phosphor is dispersed in a binder.

  By forming the phosphor layer 101 on the entire surface of the support 71 in this way, the entire support 71 emits light uniformly by the light emission of the blue LED 73A, and light amount unevenness in the light exit window 89 is less likely to occur. Further, even if the reflected light returns from the light exit window 89 at the tip of the tapered columnar body 79, the reflected light is blocked by the phosphor layer 101, and the temperature rise of the support 71 and the blue LED 73A can be prevented.

  Further, as shown in FIG. 9, the phosphor may be dispersed in the tapered columnar body 79C. In this case, the phosphor is excited to emit light while light emitted from the blue LED 73A is totally reflected and guided in the tapered column 79C, and most of the light emission components of the phosphor reach the light exit window 89 and exit. Is done. Thereby, the light emitting component of the phosphor can be extracted efficiently, which can contribute to an increase in the amount of emitted light.

  Furthermore, as described above, white light is generated by the combination of the emitted light of the LED and the phosphor, so that the color rendering can be improved as compared with the white light by the combination of the laser beam and the phosphor. That is, as shown in an example of the emission spectrum in FIG. 10, when white light is generated by a combination of a laser beam and a phosphor, the wavelength band of the short-wavelength laser beam is narrow as shown by the dotted line in the figure. Wavelength loss tends to occur between the fluorescence spectrum from the body.

  On the other hand, the LED has a broad wavelength light because the emission spectrum width W of the LED is wider than that of the laser light, and the spectrum of the fluorescence from the phosphor also contributes as excitation light in various wavelength bands. Moreover, the wavelength defect between the light emission of the LED and the light emission from the phosphor is improved by the intensity increase H. Thereby, the white light by the combination of LED and fluorescent substance has high color rendering property, and becomes illumination light more suitable for observation.

Next, in order to prevent heat generation at the connection portion between the light source unit 63 and the light guide LG, a configuration example in which an infrared component is removed from the light emitted from the light emitting unit 75 and then introduced into the light guide LG will be described.
FIG. 11A is a configuration diagram illustrating an example in which an infrared absorber is provided as a light exit window of a light collecting member 77 including a plurality of tapered columnar bodies 79. In this configuration example, an infrared cut filter 105 that is an infrared absorber is provided between the light collecting member 77 and the light guide LG, and infrared light (heat rays) is collected from the light collected by the light collecting member 77 by the infrared cut filter 105. And only the light component transmitted through the infrared cut filter 205 is introduced into the light guide LG. Thereby, on the light guide LG side, the temperature rise resulting from light introduction is prevented.

  Although not shown, by forming an antireflection film (AR coating layer) on the surface of the infrared cut filter 105, reflection at the interface of the infrared cut filter 105 can be eliminated, and return light is generated toward the light source. Can be prevented.

  FIG. 11B is a configuration diagram illustrating an example in which a stub having a multilayer reflective film that selectively reflects an infrared component is provided in the light exit window 89 of the light collecting member 77. In this configuration example, a dichroic prism 107 having a multilayer reflective film is provided between the light condensing member 77 and the light guide LG, and infrared irradiance is removed from the light collected by the light condensing member by the dichroic prism 107, thereby dichroic. Only the light component transmitted through the prism 107 is introduced into the light guide LG. Thereby, similarly to the above, the temperature rise on the light guide LG side is prevented. Moreover, the infrared rays component can be more reliably removed by making the light emission window 89 which consists of transparent glass into the infrared cut filter shown to FIG. 11 (A). The same effect can be obtained by using a dichroic mirror instead of the dichroic prism 107.

  FIG. 11C is a configuration diagram showing an example in which a stub having an infrared reflection function is provided in place of the dichroic prism of FIG. In this configuration example, the infrared reflecting glass 109 is provided between the light collecting member 77 and the light guide LG. The infrared reflecting glass 109 is configured by forming a laminated structure using titanium oxide and silicon oxide as main raw materials on the surface of a transparent glass body, for example. Thereby, similarly to the above, the temperature rise on the light guide LG side is prevented.

  Next, a control example of the light emitting unit 75 that changes the irradiation range of light introduced into the light guide LG by performing emission light amount control of a plurality of LEDs will be described. FIG. 12A is an explanatory diagram schematically showing the state of light introduction into the light guide LG when the large-diameter light guide LG is connected to the light source device 47 (see FIG. 3). [FIG. 2] It is a top view which shows LED on the lighted support body shown to (A). In addition, although the number of LED is shown as 33 as an example, it is not restricted to this.

  As shown in FIGS. 12A and 12B, the light emitted from the plurality of white LEDs 73 on the support 71 is condensed by the light collecting member 77 in the range of the light emission window 89 and introduced into the light guide LG. Is done. The condensing member 77 bundles the tapered columns 79 described above without disturbing the arrangement, so that the arrangement pattern of the plurality of white LEDs 73 arranged on the support 71 is reduced and reproduced as it is on the light exit window 89. Shall be.

  In this case, when all the white LEDs 73 arranged on the support 71 are lit, light is emitted in the entire range from the center of the array pattern to the outer peripheral side, and light is emitted from the entire light emission window 89 toward the light guide LG. .

FIG. 13A is an explanatory view schematically showing the state of light introduction into the light guide LG when the small-diameter light guide LG is connected to the light source device 47 (see FIG. 3), and FIG. It is a top view which shows LED on the lighted support body shown to (A).
As shown in FIGS. 13A and 13B, an endoscope of a type different from those shown in FIGS. 12A and 12B (for example, a nasal endoscope or a bronchoscope) is connected to the light source device 47. The diameter of the light guide LG is reduced. In that case, among the plurality of white LEDs arranged on the support 71, the white LED 73BK closest to the outermost edge is controlled to cut off or reduce the supply power, and the white LED 73BL at the center is normally or Increase power supply control.

  Then, the outer edge of the emitted light from the white LED 73BL at the center is narrowed to the center side range indicated by the dotted line in FIG. 13A, and the light emission from the outer edge side of the light emitting window 89 is suppressed. As a result, even if the light guide LG has a small diameter, light is concentrated on the light incident surface and light does not leak to the sleeve 81 or the like other than the light incident surface of the light guide LG.

  As shown in FIGS. 13 (A) and 13 (B) above, in the case of selectively controlling the amount of emitted light of a plurality of light emitters, the light emitting section 73 may be connected as shown in FIG. FIG. 14 shows the light emitting unit 75 as a configuration of each of 4 × 4 white LEDs 73, and a simplified connection circuit thereof.

  As shown in the figure, the plurality of white LEDs 73 are arranged in a lattice pattern, and are divided into LED groups on the outer peripheral side and the inner peripheral side, and the respective LED groups are divided into the inner peripheral driver 111 and the outer peripheral driver 113. Control individually. In the illustrated example, it is divided into two parts, the inner peripheral side and the outer peripheral side. However, a connection structure in which the number of divisions is further increased in accordance with the number of light emitters may be used. Can be controlled.

  For example, as shown in FIG. 1, when the endoscope 11 is connected to the light source device 47, the control unit 45 reads the individual information that the memory 43 of the endoscope has, and the type of the connected endoscope 11 The light source driver 65 is controlled based on (including information on the diameter of the light guide LG) and information on various characteristics. The light source driver 65 determines the amount of light emitted from the inner and outer LED groups shown in FIG. 14 according to the diameter of the light guide LG of the connected endoscope 11. Control by the driver 113.

  That is, in the case of a large-diameter light guide LG, the LED group on the inner peripheral side and the LED group on the outer peripheral side are set to the same light amount, and in the case of a small-diameter light guide LG, the light amount of the LED group on the inner peripheral side is increased. The light quantity of the LED group on the outer peripheral side is reduced or turned off. In addition to current control, voltage control, and on / off control, light amount control can be performed by PWM control of drive signals, pulse number control, pulse amplitude control, or a combination of these.

  In addition to the light amount control for each LED group as shown in FIG. 14, the light emitter connection circuit may have a method of individually controlling the light amount of each light emitter. In that case, an outgoing light pattern from the light outgoing window 89 can be freely formed as an arbitrary pattern.

FIGS. 15A, 15 </ b> B, 15 </ b> C, and 15 </ b> D schematically show an example of the outgoing light pattern in the light outgoing window 89. The emission light pattern is shown together with the arrangement position of the white LED 73 in the drawing, assuming that the arrangement pattern of the white LED 73 as a light emitter is reduced and reproduced as it is in the light emission window 89.
FIG. 15A shows an example of an outgoing light pattern that is divided into concentric blocks, and is composed of a central block that is divided by dotted lines in the figure and an annular block on the outer periphery thereof. FIG. 15B is an example of an outgoing light pattern that is divided into blocks in the circumferential direction, and includes a plurality of blocks that are divided at a predetermined circumferential angle. FIG. 15C shows an example in which block division in the radial direction and the circumferential direction is combined. FIG. 15D shows an example in which the light amount is set at random.

  According to these emission light patterns, in addition to the adjustment based on the difference in the diameter of the light guide LG, the adjustment of changing the light amount from the center of the light emission window 89 in the circumferential direction, and the emission light amount of the entire light emission window 89 are made uniform. It is also possible to adjust to.

  That is, as shown in FIG. 16 with the distal end portion 35 and the connector portion 25A of the endoscope 11A, the light guide LG sandwiches the imaging optical system having the imaging element 21 and the objective lens unit 39 at the endoscope distal end portion 35. When the light beam is branched into LG1 and LG2, it is necessary to emit illumination light equally from both irradiation ports 37A and 37B connected to LG1 and LG2.

  The light guide LG accommodated in the protective pipe 83 protruding from the connector portion 25A is generally divided into two with the boundary line P-P as a boundary without the LG1 bundle and the LG2 bundle being mixed with each other. Arranged. Therefore, if there is a light amount distribution in the circumferential direction of the light exit window 89, the amount of light emitted from the irradiation ports 37A and 37B becomes non-uniform.

  In that case, by adjusting the emitted light quantity of each block individually, the equal light quantity can be supplied to LG1 and LG2, and the uniform illumination light can be emitted from both irradiation ports 37A and 37B.

  In addition to individually controlling the amount of emitted light for each block, as shown in FIG. 17, skew processing for evenly mixing LG1 and LG2 optical fibers may be performed. In this case, it is not necessary to divide the light exit window 89 into blocks in the circumferential direction.

  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. That is, in the above description, an example of application to a medical endoscope apparatus that performs observation and treatment of a living tissue is shown. However, the present invention is not limited thereto, and may be an industrial endoscope apparatus. The present invention can be applied not only to a mirror device but also to other lighting devices that guide light with a fiber bundle. Further, although the LED is used as the light emitter in the above configuration, the laser light from the laser light source may be guided to the lattice-like light emission positions on the support 71 described above. Further, the tapered column 79 may be a tapered fiber having a diameter gradually reduced from one end side to the other end side, which is made by heating and stretching a multicomponent glass fiber preform. Further, the number of light emitters to be introduced into the tapered columnar body 79 is not limited to a single one, and light emitted from a plurality of light emitters may be introduced. In that case, the dynamic range of the light intensity of the light exit window 89 can be expanded by individually controlling the amount of light emitted from each light emitter.

As described above, the following items are disclosed in this specification.
(1) A light emitting unit in which a plurality of light emitters are arranged on a support, a light guide member that introduces light from the light emitting unit into an incident surface on one end side and emits illumination light from an exit surface on the other end side; A light condensing member disposed between the light emitting unit and the light guide member, and condensing light from the light emitting unit on an incident surface of the light guide member,
The light condensing member is composed of a plurality of tapered columns that taper toward the incident surface of the light guide member,
Proximal end portions of the plurality of tapered columnar bodies are respectively arranged facing the light emitting surface of the light emitter,
A light exit window that binds the tip ends of the plurality of tapered columnar bodies is formed on a side facing the incident surface of the light guide member;
A light source device further comprising light amount control means for controlling the amount of light emitted from the plurality of light emitters.
According to this light source device, the light intensity distribution introduced into the light guide member can be freely controlled by the light amount control means when the surface emission light composed of the plurality of light emitting elements is irradiated to the observation region through the light guide member. By making it adjustable, the intensity distribution of the illumination light can be made uniform with high accuracy, and illumination light without unevenness can be generated.

(2) The light source device of (1),
A light source device in which one of the light emitters of the light emitting unit is disposed facing each base end of each of the plurality of tapered columns.
According to this light source device, since one light emitter is arranged corresponding to one taper column, most of the emitted light from each light emitter can be taken into the taper column, and the light Use efficiency can be improved.

(3) The light source device according to (1) or (2),
A light source device in which the light quantity control means individually controls the emitted light quantity of each of the plurality of light emitters.
According to this light source device, by individually controlling the amount of light emitted from each light emitter, the intensity distribution of the obtained illumination can be set finely, and more uniform illumination light can be obtained.

(4) The light source device of (1) or (2),
For a plurality of groups in which the plurality of tapered columns are concentrically divided from the center of the light exit window,
The light source device in which the light amount control unit individually controls the emitted light amount of the light emitter corresponding to each tapered column body for each group.
According to this light source device, since the light emitters are individually controlled to be turned on and off for each of the annular groups divided concentrically, the light amount can be changed to different light amounts on the inner peripheral side and the outer peripheral side on the incident surface of the light guide member. An outgoing light pattern can be freely generated.

(5) The light source device of (3),
The light source device in which the light quantity control unit controls the emitted light quantity of the light emitter for each of a plurality of groups divided in a circumferential direction of an incident surface of a light guide member of the light exit window.
According to this light source device, lighting control of the light emitters is performed for each group divided in the circumferential direction, and thus the light amount distribution in the circumferential direction on the incident surface of the light guide member can be freely set.

(6) The light source device according to any one of (1) to (4),
A light source device in which the light emitter is a light emitting diode.
According to this light source device, the replacement life of the light source is long, it is possible to achieve a power-saving and compact configuration, and when white light is generated in combination with a phosphor, the spectrum can be broadened. Can be improved.

(7) The light source device according to any one of (1) to (6),
A light source device in which a phosphor layer that emits light by excitation from light from the light emitter is formed on a surface of the support on which the plurality of light emitters are arranged.
According to this light source device, the entire support emits light uniformly, and unevenness in the amount of light in the light exit window is less likely to occur.

(8) any one of the light source devices of (1) to (7);
An endoscope that includes: an endoscope that irradiates an observation region with light emitted from the light source device via the light guide member.
According to this endoscope apparatus, it is possible to always stably irradiate a region to be observed with high-intensity illumination light with little luminance unevenness, and further improve the diagnostic accuracy by the endoscope.

(9) The endoscope apparatus according to (8),
The endoscope includes individual information holding means having individual information of the endoscope,
An endoscope apparatus in which the light source device controls an emitted light amount of the light emitter based on the individual information read from the individual information holding unit.
According to this endoscope apparatus, based on the individual information of the endoscope connected to the light source device, it is possible to control the light emitter suitable for this endoscope.

(10) The endoscope apparatus according to (9),
An endoscope apparatus in which the individual information includes information related to a diameter of a light guide member of the endoscope.
According to this endoscope apparatus, when the light guide member has a large diameter or a small diameter from the light emitting unit, light can be introduced into the light guide member under different irradiation conditions, and the optimum for the type of the light guide member Can produce a simple illumination light.

DESCRIPTION OF SYMBOLS 11 Endoscope 13 Control apparatus 19 Endoscope insertion part 25A, 25B Connector part 35 Endoscope front-end | tip part 43 Memory (individual information holding means)
45 Control unit 47 Light source device 49 Processor
63 Light source section 65 Light source driver (light quantity control means)
71 Support 73 White LED (light emitter)
73A Blue LED (light emitter)
73BK OFF LED
73BL lighting LED
75 Light Emitting Unit 77 Light Condensing Member 79 Tapered Column 79a Tip 89 Light Exit Window 95 White LED (auxiliary light emitter)
101 phosphor layer 111 inner peripheral side driver 113 outer peripheral side driver LG light guide

Claims (10)

A light-emitting unit in which a plurality of light-emitting bodies are arranged on a support, a light guide member that introduces light from the light-emitting unit into an incident surface on one end side and emits illumination light from an output surface on the other end side, and the light-emitting unit A light condensing member that is disposed between the light guide member and condenses light from the light emitting unit on an incident surface of the light guide member,
The light condensing member is composed of a plurality of tapered columns that taper toward the incident surface of the light guide member,
Proximal end portions of the plurality of tapered columnar bodies are respectively arranged facing the light emitting surface of the light emitter,
A light exit window that binds the tip ends of the plurality of tapered columnar bodies is formed on a side facing the incident surface of the light guide member;
A light source device further comprising light amount control means for controlling the amount of light emitted from the plurality of light emitters. The light source device according to claim 1,
A light source device in which one of the light emitters of the light emitting unit is disposed facing each base end of each of the plurality of tapered columns. The light source device according to claim 1 or 2,
A light source device in which the light quantity control means individually controls the emitted light quantity of each of the plurality of light emitters. The light source device according to claim 1 or 2,
For a plurality of groups in which the plurality of tapered columns are concentrically divided from the center of the light exit window,
The light source device in which the light amount control unit individually controls the emitted light amount of the light emitter corresponding to each tapered column body for each group. The light source device according to claim 4,
The light source device in which the light quantity control unit controls the emitted light quantity of the light emitter for each of a plurality of groups divided in a circumferential direction of an incident surface of a light guide member of the light exit window. The light source device according to any one of claims 1 to 5,
A light source device in which the light emitter is a light emitting diode. The light source device according to any one of claims 1 to 6,
A light source device in which a phosphor layer that emits light by excitation from light from the light emitter is formed on a surface of the support on which the plurality of light emitters are arranged. The light source device according to any one of claims 1 to 7,
An endoscope that includes: an endoscope that irradiates an observation region with light emitted from the light source device via the light guide member. The endoscope apparatus according to claim 8, wherein
The endoscope includes individual information holding means having individual information of the endoscope,
An endoscope apparatus in which the light source device controls an emitted light amount of the light emitter based on the individual information read from the individual information holding unit. The endoscope apparatus according to claim 9, wherein
An endoscope apparatus in which the individual information includes information related to a diameter of a light guide member of the endoscope.