JP2006261048A - Multi-point light source unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multi-point light source unit in which color-rendering effect is improved without arranging a diffusion plate or the like in front of an LED and emitting color can be easily changed by a simple drive circuit. <P>SOLUTION: The light emitting elements 3 all having same emitting wavelength are used and phosphors 4 of different kinds are used, and thereby, a plurality of illumination light having different emitting wavelength is irradiated to the outside. When, as the light emitting elements 3, LEDs which emit ultraviolet light are used, the emitting wavelength of the ultraviolet light is converted into orange, yellow, green, and blue and irradiation light of four wavelength is emitted, and thereby, the whole illumination light is made white. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a multi-point light source unit that uses a light emitting element such as an LED, which can be used as a backlight light source for medical lighting equipment, general lighting equipment, liquid crystal monitors, and liquid crystal TVs as a light source.

  2. Description of the Related Art In recent years, for example, lighting devices using light emitting diodes (LEDs) as light sources have been used in various fields. As such an illuminating device, an illumination device including an LED that emits ultraviolet rays and a phosphor that absorbs the ultraviolet rays and emits white light is known.

In addition, as another lighting device, it is configured by integrating a plurality of LEDs each emitting light in R (red), G (green), and B (blue), and a white lighting device is formed by mixing these LEDs. (For example, refer to Patent Document 1).
JP 2003-100108 A

  The illuminating device that generates white light from a phosphor from the ultraviolet light emitted from the former light emitting diode has a configuration in which white light is generated by a single LED, and thus there is a problem that the emission color cannot be changed. .

  Further, in the illumination device formed by integrating the latter plurality of LEDs, since each of R, G, and B has a steep three-wavelength spectrum, the light colors of R, G, and B are separated in hue, As it is, it is difficult to mix the colors, the uniformity is inferior, and the color rendering is also inferior. As a result, in order to improve this uniformity, it was necessary to arrange a diffusion plate or the like in front of the LED. In addition, since the driving voltages of the LEDs of R, G, and B are different, there is a problem that the driving circuit becomes complicated.

  The present invention can improve the uniformity without disposing a diffusion plate or the like in front of the LED, improve the color rendering, and can easily change the emission color with a simple drive circuit. Let it be an issue.

  The multi-point light source unit of the present invention is made to solve the above-described problems, and a plurality of substrate portions, light emitting elements such as LEDs provided on each substrate portion, and light of the light emitting elements are transmitted. A phosphor disposed in front of each light emitting element, and a lens disposed in front of each phosphor, the light emitting elements have the same emission wavelength, and the phosphor is light of the light emitting element. Is converted to a predetermined emission wavelength.

  Moreover, the light emitting element is preferably composed of a UV-LED that irradiates ultraviolet rays, and the phosphor is preferably composed of a plurality of types that convert the illumination light into different wavelengths so as to whiten the illumination light.

  Further, the multipoint light source unit of the present invention is disposed in front of the light emitting element so that the substrate part, a plurality of light emitting elements such as LEDs provided on the substrate part, and the light of the light emitting element are transmitted. A phosphor unit having a plurality of phosphor parts; and a lens disposed in front of the phosphor unit, wherein the light emitting element has the same emission wavelength, and the phosphor unit emits a plurality of light from the light emitting element. Is converted to a predetermined emission wavelength.

  Further, the light emitting element is an LED that irradiates ultraviolet rays, and the phosphor unit is provided with a plurality of types of fluorescent parts so as to whiten the illumination light. Further, the number of LEDs is four, and the fluorescent part of the phosphor unit is configured to convert the emission wavelength of ultraviolet rays into wavelengths of orange, yellow, green, and blue, respectively.

  All the light emitting elements of the multipoint light source unit of the present invention have the same emission wavelength, and by using different phosphors, it is possible to irradiate a plurality of illumination lights having different emission wavelengths to the outside. When using an LED that irradiates ultraviolet rays as a light emitting element, the entire illumination light is obtained by irradiating four wavelengths of irradiation light by converting the emission wavelength of the ultraviolet rays into orange, yellow, green, and blue wavelengths. Can be whitened.

  The present invention can improve uniformity without disposing a diffuser plate or the like in front of a light emitting element such as an LED, and also improves color rendering, making it easy to obtain a desired light emission color with a simple drive circuit. Obtainable.

  Embodiments of the present invention will be described with reference to the drawings. 1 and 2 show Embodiment 1 according to the present invention, and FIG. 1 is an overall exploded perspective view of the light source unit and FIG. 2 is a cross-sectional view of the light source.

  The light source unit 1 includes a plurality of light sources. In the present embodiment, the light source unit 1 includes, for example, four light sources 1A to 1D. Each of the light sources 1A to 1D includes a light source substrate 2, a light emitting diode (hereinafter referred to as an LED) 3 composed of, for example, a UV-LED that emits ultraviolet rays as a light emitting element, and a phosphor 4 disposed in front of the LED 3. And lens 5. All the LEDs 3 have the same emission wavelength. The same emission wavelength means the emission wavelength in the ultraviolet region when the light emitting element is a UV-LED that emits ultraviolet rays.

  The light source substrate portion 2 has a rectangular shape when viewed from the front, and a recess 21 for detachably housing the LED 3 and the phosphor 4 is formed on the front surface thereof. The concave portion 21 includes a small concave portion 21 a that accommodates the LED 3 and a large concave portion 21 b that accommodates the phosphor 4. Reference numeral 22 denotes an electrode that protrudes from the light source substrate 2 and is connected to the LED 3.

  As shown in FIG. 2, each phosphor 4 includes a substrate 41 made of a transparent synthetic resin, and a fluorescent portion 42 formed by applying a phosphor paint to the substrate 41. Four types of phosphors 4 are provided corresponding to the respective LEDs 3. For example, the first phosphor 4 </ b> A includes a fluorescent unit 42 that converts the wavelength into O (orange) wavelength when irradiated with ultraviolet rays from the LED 3 and irradiates the irradiation light. The 2nd fluorescent substance 4B is provided with the fluorescence part 42 which converts into the wavelength of Y (yellow) and irradiates irradiated light, when an ultraviolet-ray is irradiated from LED3. 4C of 3rd fluorescent substance is provided with the fluorescence part 42 which converts into the wavelength of G (green) and irradiates irradiation light, when an ultraviolet-ray is irradiated from LED3. The 4th fluorescent substance 4C is provided with fluorescent part 42 which changes into the wavelength of B (blue), and irradiates irradiation light, when ultraviolet rays are irradiated from LED3.

  Each lens 5 is molded from a transparent synthetic resin material or the like, and a housing portion 51 for housing the phosphor 4 and the light source substrate portion 2 is formed on the back surface portion thereof. The housing portion 51 covers the front surface and the peripheral surface of the phosphor 4 and the light source substrate portion 2. In addition, an engaging portion 53 that is detachably fitted to the rear portion of the light source substrate portion 2 is provided on the periphery of the accommodating portion 51 so as to protrude in the radial direction. Therefore, each lens 5 can be detached from the light source substrate 2 by releasing the engagement with the light source substrate 2 by deforming the engaging portion 53 against the elastic force. Thus, by removing the lenses 5 of the arbitrary light sources 1 </ b> A to 1 </ b> D, the phosphor 4 and the LED 3 accommodated in the light source substrate unit 2 can be exchanged. The lens 5 is not necessarily limited to a structure that is removed from the light source substrate unit 2, but may be a lens that is fixed to the light source substrate unit 2.

  In the multipoint light source unit 1 configured as described above, when a current is supplied from the control unit (not shown) to the LEDs 3 of the light sources 1A to 1D, the LEDs 3 are turned on. Light irradiated by the LED 3 of the light source 1A is excited and transmitted through the first phosphor 4A and is converted into an O wavelength. Illumination light from the LED 3 of the light source 1B is excited and transmitted through the second phosphor 4B and converted to a Y wavelength. Illumination light from the LED 3 of the light source 1C is excited and transmitted through the third phosphor 4C and converted to a G wavelength. Illumination light from the LED 3 of the light source 1D is excited and transmitted through the fourth phosphor 4D and converted into a wavelength of B. Thus, the whole irradiation light can be whitened by irradiating the irradiation light of four wavelengths outside.

  3 to 5 show a second embodiment of the present invention. The multipoint light source unit 1 of the second embodiment includes a light source substrate portion 2A to which a plurality of (four in the present embodiment) LEDs 3 having the same emission wavelength are detachably attached, a phosphor unit 40, It is composed of a single lens unit (lens) 5A.

  A single large concave portion 21c is formed on the front surface of the light source substrate portion 2A, and a plurality of small concave portions 21d corresponding to the LEDs 3 are formed on the bottom surface of the large concave portion 21c. The LED 3 is detachably accommodated in each small recess 21d, and the phosphor unit 40 is detachably accommodated in the large recess 21c.

  The phosphor unit 40 includes a substrate 41 made of a transparent synthetic resin and a plurality of phosphor portions 42A to 42D applied to the front surface of the substrate 41. The fluorescent portions 42A to 42D are formed by applying four types of fluorescent paints as in the first embodiment. 42 A of 1st fluorescence parts will convert into the wavelength of O, if an ultraviolet-ray is irradiated from LED3. The second fluorescent part 42B converts to the Y wavelength when irradiated with ultraviolet rays. The third fluorescent part 42C converts to the G wavelength when irradiated with ultraviolet rays. The fourth fluorescent part 42D converts the wavelength of B when irradiated with ultraviolet rays.

  The lens unit 5A has an accommodating portion 51 and an engaging portion 53 like the lens 5, and the engaging portion 53 is detachably fitted to the light source substrate portion 2A so as to cover the phosphor unit 40. ing.

  The multipoint light source unit 1 is connected to a control unit 8 via a cable 7 as shown in FIG. For example, when the color of each light source is fixed and turned on (for example, as shown in FIG. 6A), the control unit 8 connects the LEDs 3 in series, or as shown in FIG. Or a DC-DC converter). Then, when current is supplied from the control unit 8 to the LEDs 3 of the light sources, the LEDs 3 are turned on.

  Illumination light (ultraviolet light) from the LED 3 is excited and transmitted through the first fluorescent part 42A and converted to an O wavelength. The illumination light from the LED 3 is excited and transmitted through the second fluorescent part 42B and is converted into a Y wavelength. The illumination light from the LED 3 is excited and transmitted through the third fluorescent part 42C and converted to the G wavelength. The illumination light from the LED 3 is excited and transmitted through the fourth fluorescent part 42D and is converted into a wavelength of B. Thus, the whole irradiation light can be whitened by irradiating the irradiation light of four wavelengths outside.

  In addition, as shown in FIG. 6C, the control unit 8 is a controller that changes the light emission color by controlling the current value flowing through each LED 3 and changing the RGB light mixture ratio. Is also possible. Further, it is also possible to change the emission color by controlling the pulse width of the current passed through each LED 3 by the controller and changing the RGB light mixture ratio.

  When exchanging the phosphor unit 40 and the LED 3, the lens unit 5A is removed. Then, the phosphor unit 40 and the LED 3 that have become defective due to breakage, life, or the like are removed from the light source substrate unit 2A, the new phosphor unit 40 or the like is accommodated in the light source substrate unit 2A, and terminals are connected. Furthermore, by fitting the lens unit 5A, the phosphor unit 40 and the like can be replaced easily and quickly, and only the parts necessary for the replacement can be replaced.

  FIG. 7 shows a modification of the second embodiment. Specifically, an entrance / exit opening 55 is formed on one side of the lens unit 5A, and the phosphor unit 40 can be inserted / extracted between the lens unit 5A and the light source substrate 2A through the entrance / exit opening 55.

  In the present embodiment, R is divided into O and Y, and a color mixture of four wavelengths of OYGB is adopted, but it is also possible to irradiate R with a single light source. In such a case, the light source unit is constituted by three LEDs.

  The multi-point light source unit of the present invention also has good light-condensing property due to the lens (lens unit), and has a lens as compared with the conventional one in which a plurality of LEDs are integrated for phosphor excitation by the LED. Despite this, hue separation is unlikely to occur and light mixing is easy, and as a result, a diffusion plate is not required. Further, the phosphor excitation by the UV-LED emits light in a wide spectrum and therefore has good color rendering.

  Further, since a plurality of LEDs of the same type are driven, the drive circuit is simplified and the emission color can be easily controlled. In addition, by controlling the plurality of LEDs separately, it is easy to change white color temperature or full color.

  The multipoint light source unit of the present invention can be employed as a medical lighting apparatus. Particularly, since the light source is unitized in the second embodiment, the size can be reduced. When the multipoint light source unit of the present invention is used as a light source for an endoscope, a red difference in a human internal organ or a tumor can be clearly seen. In addition, when used as a surgical light source, in addition to the above effects, the difference between arteries and veins of blood vessels can be clearly seen. Further, when the multi-point light source unit is used in a color temperature variable instrument, it can be switched between daylight color, day white, and warm white according to the mental state of the user.

  In addition, the multi-point light source unit of the present invention is for general illumination light sources that require color rendering and color reproducibility, illumination light sources for changing colors, liquid crystal monitors, and backlights for liquid crystal TVs with good color reproducibility. Ideal for light sources (good color reproducibility).

  The phosphor 11 is not limited to that of the above-described embodiment, and may be a plate-like material, not a coated material, or a combination of a plate-shaped material and a coated material. . In addition to the UV-LED, the light emitting element may be a device that can excite a phosphor, such as a purple LED or a blue LED.

It is a disassembled perspective view which shows the whole Embodiment 1 of this invention. It is sectional drawing of the light source. It is a disassembled perspective view which shows the whole Embodiment 2 of this invention. It is sectional drawing of the light source unit. It is a side view which shows the example of use. (A)-(c) is a circuit diagram of a light source unit. The modification of Embodiment 2 of this invention is shown, (a) is a perspective view of the state which mounted | wore the fluorescent substance unit, (b) is a perspective view of the state which takes out a fluorescent substance unit.

Explanation of symbols

2, 2A Light source substrate (substrate)
3 UV-LED (light emitting device)
4 phosphor 5 lens 5A lens unit 40 phosphor unit

Claims (5)

  A plurality of substrate portions, light emitting elements such as LEDs provided on each substrate portion, a phosphor disposed in front of each light emitting element so that light from the light emitting elements is transmitted, and in front of each phosphor A multi-point light source unit, wherein the light emitting element has the same emission wavelength, and the phosphor converts light of the light emitting element into a predetermined emission wavelength.   2. The multipoint light source unit according to claim 1, wherein the light emitting element is composed of an LED that irradiates ultraviolet rays, and the phosphor is composed of a plurality of types that convert illumination light into different wavelengths so as to whiten the illumination light. .   A phosphor unit having a substrate part, a plurality of light emitting elements such as LEDs provided on the substrate part, and a plurality of fluorescent parts arranged in front of the light emitting element so that light of the light emitting element is transmitted; A lens disposed in front of the phosphor unit, the light emitting elements have the same emission wavelength, and the phosphor unit converts light of the light emitting element into a plurality of predetermined emission wavelengths. Multi-point light source unit.   The multipoint light source unit according to claim 3, wherein the light emitting element is an LED that irradiates ultraviolet rays, and the phosphor unit is provided with a plurality of types of fluorescent portions so as to whiten illumination light. . The multi-point light source unit according to claim 4, wherein the number of LEDs is four, and the fluorescent part of the phosphor unit converts the emission wavelength of ultraviolet light into orange, yellow, green, and blue wavelengths, respectively.

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