JP4331077B2 - LED light source device and spotlight - Google Patents

Description

  The present invention relates to an LED light source device using a light emitting diode (LED) and a spotlight.

  Generally, halogen light bulbs and discharge lamps are used as light sources for spotlights used for lighting in theaters and television studios. This is because the light emitting portion of the light source is sufficiently small with respect to the lens, and the lens can sufficiently capture the light from the light source and can irradiate efficiently. In a spotlight using a halogen bulb or a discharge lamp, the filament is heated as high as possible to generate light, so that not only visible light but also a lot of heat rays are emitted. Therefore, a metal plate that can withstand heat is used for the housing for storing the light source, and heat-resistant glass is used for the lens. Therefore, the spotlight becomes heavy and labor is required to move the spotlight.

  Accordingly, with the recent increase in luminous intensity of LEDs, there are also demands for power saving and low heat generation, and thus LEDs are attracting attention as light sources for spotlights. An LED spotlight using light emitting diodes (LEDs) has a large number of LEDs arranged as a light source and condenses the irradiation beam of each LED at one point to form a virtual single point light source unit. A spotlight has been developed in which the illuminance and the illuminance distribution on the surface to be irradiated are changed by changing the positional relationship between the light source and the surface (see, for example, Patent Document 1).

On the other hand, as an illumination light source device used as a light source of an image recording device or a backlight of a liquid crystal display device, light from an LED light source is reflected and transmitted by a reflecting plate and scattered by passing through the scattering plate, so that each color of BGR is There is one in which evenly mixed light is uniformly irradiated in a slit shape so that it can be illuminated with uniform illuminance (see, for example, Patent Document 2).
Japanese Patent Laid-Open No. 2001-307502 (FIGS. 2 and 3) JP-A-7-290760 (FIG. 1)

  However, in Patent Document 2, in order to eliminate the illumination unevenness for each arrangement pitch that occurs when the point-like elements are arranged in a line and irradiated as they are, the light is irradiated in a line by a waveguide. A light source that is used for a light source of an image recording device or a backlight of a liquid crystal display device, and that illuminates an irradiated object in a spot manner, such as a spotlight used for illumination in a television studio or the like Not suitable for.

  A spotlight requires a large number of LEDs to ensure brightness, and even if white LEDs of the same color are prepared, a desired color or color temperature may not be obtained due to product variations. Further, there is a demand for obtaining spot colors having a light color or color rendering property that cannot be obtained with a single light. In order to meet this requirement, a complementary color LED is provided in addition to the white LED. However, if the irradiated object is irradiated as it is from the white LED and the complementary color LED, the color may not be sufficiently mixed and uneven color may occur. .

  That is, when LEDs are used as the light source of the spotlight, a large number of LEDs are positioned to obtain a sufficient amount of light, and the light is emitted from all the LEDs to collect light at a single point in order to obtain the effect of continuous change in irradiation area and light amount. The collected light is irradiated through a condenser lens. At this time, depending on the position of the condensing lens, the light beam of the LED may be directly projected onto the irradiation surface, which may result in irradiation light with noticeable color unevenness.

  Therefore, it is conceivable to mix the light emitted from the LED and the collected light by diffusing the light through the diffusion plate. In this case, the diffused light from the diffusion plate is too diffused so that the light is collected at one point. It becomes difficult to collect light or to irradiate light to the condenser lens. Accordingly, the amount of light applied to the irradiated object is reduced, the light output efficiency is lowered, and it becomes unsuitable as a spotlight.

  An object of the present invention is to provide an LED-type light source device and a spotlight that can obtain light color and color rendering spot light that cannot be obtained with a single light without reducing the light output efficiency.

  An LED light source device according to a first aspect of the present invention is an LED array portion in which a plurality of white LEDs and a plurality of complementary color LEDs are mounted so that a light beam is directed to a predetermined position; An aperture portion that has an aperture at a predetermined position where the light beam of the LED converges and emits the condensed light; and is provided close to the front surface of the complementary color LED having poor color mixing among the complementary color LEDs and passes through the aperture A diffusing plate having a diffusing angle at which the diffused light is about the aperture diameter.

  In the present invention and the following inventions, definitions and technical meanings of terms are as follows unless otherwise specified. The LED array part is formed in a bowl shape with an insulating material, for example, and the plurality of LEDs are arranged in close contact with the bowl-shaped concave surface, and arranged side by side so that the light beams from the plurality of LEDs are directed to a predetermined position. . The plurality of LEDs are composed of a plurality of white LEDs for main beams and a plurality of complementary color LEDs for complementary colors. The complementary color LEDs are, for example, a red LED, a green LED, a blue LED, and the like. These LEDs include both so-called power-type LEDs and bullet-type LEDs. When only power-type LEDs are arranged, when only bullet-type LEDs are arranged, both power-type LEDs and bullet-type LEDs are arranged. Including both cases. The power type LED is a high watt type, has a large light output, and generates a large amount of heat as compared with the bullet type LED.

  The aperture section has an aperture at a predetermined position where the light beams of the plurality of LEDs attached to the LED array section are condensed. The aperture collects the light beams of the plurality of LEDs, for example, collects spotlights. Ejected toward the optical lens. Therefore, the aperture becomes a pseudo light source unit.

  The condensing lens is disposed apart from the aperture portion, condenses the emitted light emitted from the aperture of the aperture portion, and irradiates the external irradiated body, and includes a spherical lens and a flat lens. It also includes the case of having a two-group lens using one or two or more lenses.

  The diffusion plate is provided close to the front surface of a complementary color LED having a poor color mixing property, for example, a red LED among the complementary color LEDs attached to the LED array portion. The diffuser plate has directivity characteristics in a predetermined direction, and diffuses light at a narrow diffusion angle in the predetermined direction. Accordingly, a diffusion plate having a diffusion angle is provided on the front surface of the complementary color LED having poor color mixing properties so that when the diffused light passing through the diffuser passes through the aperture, the diffused light diffuses about the aperture diameter.

  According to the present invention, the diffuser plate attached to the front surface of the complementary color LED with poor color mixing is used with a unique directivity characteristic that diffuses diffused light to the same extent as the aperture diameter. Thus, the diffusion effect can be obtained without impairing the irradiation angle. Therefore, color unevenness can be efficiently eliminated.

  According to a second aspect of the present invention, there is provided the LED light source device according to the first aspect of the present invention, wherein the diffused light provided between the aperture of the aperture section and the condensing lens is irradiated with the condensing lens. A diffusion plate having a diffusion angle that is about the lens diameter is provided.

  The present invention is different from the invention of claim 1 in that another diffusion plate is provided between the aperture of the aperture portion and the condenser lens. This diffusion plate has directivity characteristics in a predetermined direction, diffuses light at a narrow diffusion angle in the predetermined direction, and diffuses the diffused light irradiated to the condensing lens to the extent of the condensing lens diameter Have an angle. That is, a diffusion plate that diffuses to the same extent as the taking-in angle of the condenser lens is used.

  According to the present invention, since the diffusion plate having the diffusion characteristics in consideration of the taking-in angle of the condensing lens is provided, the color unevenness and the light distribution unevenness can be eliminated without deteriorating the light characteristic efficiency.

  A spotlight according to a third aspect of the present invention is an LED light source device according to any one of the first or second aspect; a spotlight body that houses the LED light source device; and the spotlight body that is housed in the spotlight body. A condensing lens that condenses the light from the LED light source device and emits the light to the outside; and a moving mechanism that relatively varies the distance between the LED light source device and the condensing lens. To do.

  The spotlight main body is formed of, for example, a metal box, and houses the LED light source device according to any one of claims 1 and 2. The condensing lens is disposed in the spotlight body apart from the LED light source device, and condenses the emitted light emitted from the LED light source device, and includes a spherical lens and a flat lens. It also includes the case of having a two-group lens using one or two or more lenses. The moving mechanism makes the distance between the condensing lens and the LED light source device relatively variable, and by focusing with this moving mechanism, the irradiation area on the irradiated surface can be continuously changed, In addition, the amount of light can be continuously changed.

  According to the present invention, light from a plurality of LEDs is mixed by the LED light source device, and the mixed light is collected by the condenser lens and is focused by the moving mechanism. However, even if the image is blurred, the irradiated surface can be illuminated without any irradiation deviation.

  According to the first aspect of the present invention, since the diffuser plate attached to the front surface of the complementary color LED having poor color mixing property has a characteristic of directivity that diffuses diffused light to the same extent as the aperture diameter, the complementary color is used. A diffusion effect can be obtained without impairing the irradiation angle inherent to the LED. Therefore, color unevenness due to complementary color LEDs having different characteristics can be eliminated, and color rendering can be obtained efficiently.

  According to the second aspect of the present invention, since the diffusion plate having the diffusion characteristic in consideration of the taking-in angle of the condenser lens is provided, the light characteristic efficiency of the irradiation light to the irradiated object is not deteriorated and the color unevenness is arranged. Uneven light can be eliminated.

  According to the invention of claim 3, the light from the plurality of LEDs is mixed by the LED type light source device, and the mixed light is collected by the condenser lens and focused by the moving mechanism. Irradiation deviation does not occur even when it is not matched or blurred, and the irradiated surface can be illuminated.

(First embodiment)
FIG. 1 is a configuration diagram of an LED type light source apparatus 11 according to the first embodiment of the present invention. A plurality of LEDs 13 are attached to the LED array section 12, and complementary color LEDs 13b1 and 13b2 are attached in addition to the white LED 13a of the main beam. A diffusion plate 14 is provided on the front surface of the complementary color LED 13b2 having a poor color mixing property among the complementary color LEDs 13b1 and 13b2.

  The plurality of LEDs 13 of the LED array unit 12 are arranged side by side so that the light beams from the LEDs 13 face the aperture 16 of the aperture unit 15. As the LED 13, a power type LED having a large light output or a bullet type LED having a normal light output is used, and each LED 13 emits a light beam so that the center of the optical axis of the light beam is directed to the center of the aperture 16. . The aperture unit 15 condenses the light beams of the plurality of LEDs 13 attached to the LED array unit 12 by the aperture 16 and emits the light beam toward a condensing lens 17 of, for example, a spotlight.

  As described above, the aperture section 15 is arranged so that the aperture 16 is positioned at a predetermined position where the light beams of the plurality of LEDs 13 attached to the LED array section 12 are condensed. Therefore, this aperture 16 becomes a pseudo light source part. That is, the light from the plurality of LEDs 13 attached to the LED array unit 12 is a surface light source, and the light from the surface light source is condensed by the aperture 16 of the aperture unit 15 to be converted into a point light source. The 15 apertures 16 are used as pseudo light sources to emit light to the outside.

  Here, the complementary color LED 13b2 is a red LED which is different from the other in the complementary color LED 13b which performs color adjustment and is irradiated with uneven color without being well mixed with the light of the white LED 13a as a base. Therefore, a diffuser plate 14 having a narrow-angle directivity is provided in the vicinity of the front surface of the complementary color LED 13b2, and the light is incident on the aperture 16 with the intensity and distribution being optimized.

  The diffusion plate 14 is made of a material such as a resin having irregularities on one surface and has a predetermined diffusion angle. Now, assuming that the irradiation angle of the LED 13 is θ1 and the diffusion angle of the diffusion plate 14 is θ2, the diffusion plate emission angle α of the diffused light emitted from the diffusion plate 14 is expressed by equation (1).

α = (θ1 ² −θ2 ² ) ^1/2 (1)
For example, it is assumed that the irradiation angle θ1 of the complementary color LED 13b2 is θ1 = 10 °, and the diffusion angle θ2 of the diffusion plate 14 is θ2 = 10 °. In this case, the diffusion plate injection angle α is α = 14.1 ° according to the equation (1). Thereby, it is possible to obtain a spread suitable for the diameter of the aperture 16 by adjusting the arrangement position of the LED array portion 12 without being excessively diffused. Accordingly, it is possible to suppress a decrease in the efficiency of light output, and the irradiation light emitted from the condenser lens 17 is free from color unevenness and improves color rendering.

  Here, in order to brighten the irradiation light of the spotlight, it is necessary to arrange as many LEDs 13 as possible. However, since the LEDs 13 are arranged toward the aperture portion 15, the arrangement positions of the LEDs 13 are light as the number of LEDs 13 increases. The position is away from the axis. For this reason, in order for the light beam to enter the condenser lens 17 efficiently, the incident angle to the aperture 16 must be within a suitable range. For this purpose, the distance between the aperture 16 and the LED 13 is increased. It is necessary to take.

  When the distance between the aperture 16 and the LED 13 is long, it is desirable that the beam is a narrow-angle beam so that the light beam of the LED 13 is efficiently incident on the aperture 16. Since the conventional general diffusion plate is too wide to obtain a sufficient diffusion effect, the diffusion plate 14 having a narrow angle diffusion characteristic is used in the first embodiment. In this case, from the irradiation angle θ1 of the complementary color LED 13b2, the distance from the LED 13 to the aperture 16, and the diameter of the aperture 16, a diffuser plate 14 having a diffusion angle θ2 at which diffused light passing through the aperture 16 becomes approximately the diameter of the aperture 16. Will be selected.

  According to the first embodiment, the diffuser plate 14 attached to the front surface of the complementary color LED 13b2 with poor color mixing is one having a unique directivity characteristic that diffuses diffused light to the same extent as the diameter of the aperture 16. Therefore, the diffusion effect can be obtained without impairing the irradiation angle θ1 inherent to the complementary color LED 13b2. Therefore, uneven color due to the complementary color LED 13b having different characteristics can be eliminated, and color rendering can be obtained efficiently.

  Further, since the light condensed and mixed by the aperture 16 is emitted toward the condenser lens 17, the light from the LED array unit 12 which is a surface light source can be emitted to the outside as a point light source. Further, since the light beams from the plurality of LEDs 13 are arranged so as to face the aperture 16 of the aperture portion 15, unevenness in light distribution can be reduced without impairing the efficiency of light output.

(Second Embodiment)
FIG. 2 is a block diagram of an LED type light source device 11 according to the second embodiment of the present invention. This second embodiment is different from the first embodiment shown in FIG. 1 in that another diffusion plate 18 is provided between the aperture 16 of the aperture section 15 and the condenser lens 17. is there. The same elements as those in FIG. 1 are denoted by the same reference numerals, and redundant description is omitted.

  In FIG. 2, a diffusion plate 18 is provided between the aperture 16 of the aperture portion 15 and the condenser lens 17. The diffusion plate 18 has directivity characteristics in a predetermined direction, diffuses light at a narrow diffusion angle in the predetermined direction, and diffused light irradiated on the condenser lens 17 is about the diameter of the condenser lens 17. Has a diffusion angle to diffuse. That is, the irradiation light from the diffusion plate 18 is diffused to the same extent as the taking-in angle 17 of the condenser lens.

  The diffusion plate 18 diffuses the light collected from the white LED 13 a and the complementary color LED 13 b to the aperture 16 and causes the light to enter the condenser lens 17. Similarly to the diffusing plate 14, the diffusing plate 18 also has a diffusing plate exit angle α of the emitted diffused light expressed by the equation (1).

  For example, if the irradiation angle θ1 of the white LED 13a is θ1 = 10 ° and the diffusion angle θ2 of the diffusion plate 18 is θ2 = 30 °, the diffusion angle α of the diffusion plate 18 is 31.6 °, and the light is condensed. The spread and the diffusion effect that the lens 17 can capture without loss are obtained, and the irradiation light emitted from the condensing lens 17 eliminates color unevenness and improves color rendering. That is, the light from the plurality of LEDs 13 attached to the LED array unit 12 is diffused at the diffusion plate emission angle α (α = 31.6 °) of the diffusion plate 18 and diffused to the same extent as the taking-in angle of the condenser lens 17. Let

  In this case, even if the diffusion plate 14 is installed on the front surface of the complementary color LED 13b2, the diffusion plate 18 having the correct diffusion angle is used and is taken into the condenser lens 17 without loss.

That is, the diffusion plate 18 has an irradiation angle θ1 of the LED 13 (an emission angle of the diffusion plate 14), an incident angle of the LED 13 to the aperture 16, a diameter of the aperture 16, and a distance from the aperture 16 to the condenser lens 17. Select the one with suitable angle characteristics.

  According to the second embodiment, since the diffusion plate 18 having the diffusion characteristic in consideration of the taking-in angle of the condenser lens 14 is provided, the color unevenness and the light distribution unevenness are eliminated without reducing the light characteristic efficiency. be able to.

(Third embodiment)
FIG. 3 is a configuration diagram of a spotlight according to the third embodiment of the present invention, and FIG. 4 is a front view thereof. The spotlight main body 19 is formed of, for example, a metal box, and accommodates one of the LED light source devices 11 shown in FIG. 1 or FIG. In FIG. 3, the LED type light source device 11 shown in FIG. 1 is housed.

  The condensing lens 17 is disposed in the spotlight main body 19 apart from the LED light source device 11, and condenses the emitted light emitted from the LED light source device 11, and is a spherical lens or a flat lens. It is formed. FIG. 3 shows a case where one Fresnel lens is used.

  In addition, a moving mechanism 20 is provided that makes the distance between the condenser lens 17 and the LED light source device 11 relatively variable. The moving mechanism 20 includes a light source focus handle 20a and a lens focus handle 20b. By focusing with this moving mechanism 20, the irradiation area on the irradiated surface is continuously changed, and the light quantity is continuously changed. The spotlight body 19 on the condenser lens 17 side is provided with a bander 21, and the irradiation range of light from the spotlight is adjusted by adjusting the opening / closing angle of the bander 21.

  According to the third embodiment, the light from the plurality of LEDs 13 is mixed by the LED light source device 11, the mixed light is collected by the condenser lens 17, and is focused by the moving mechanism 20. As a result, the irradiated surface can be appropriately illuminated without causing an irradiation shift even when it is out of focus or blurred.

BRIEF DESCRIPTION OF THE DRAWINGS The block diagram of the LED type light source device concerning the 1st Embodiment of this invention. The block diagram of the LED type light source device concerning the 2nd Embodiment of this invention. The block diagram of the spotlight concerning the 3rd Embodiment of this invention. The front view of the spotlight concerning the 3rd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... LED type light source device, 12 ... LED arrangement part, 13 ... Complementary color LED, 14 ... Diffuser, 15 ... Aperture part, 16 ... Aperture, 17 ... Condensing lens, 18 ... Diffuser, 19 ... Spotlight main body, 20 ... Movement mechanism, 21 ... Banda

Claims (3)

An LED array portion in which a plurality of white LEDs and a plurality of complementary color LEDs are attached so that the light beam is directed to a predetermined position;
An aperture portion having an aperture at a predetermined position where the light beam of the LED attached to the LED array portion is focused;
A diffusion plate provided in the vicinity of the front surface of the complementary color LED having poor color mixing property among the complementary color LEDs and having a diffusion angle at which diffused light passing through the aperture is approximately the aperture diameter;
An LED-type light source device comprising: The diffused light that is provided between the condenser lens that emits the light condensed on the aperture of the aperture unit to the outside and the aperture of the aperture unit, and that irradiates the condenser lens is about the diameter of the condenser lens. The LED light source device according to claim 1, further comprising a diffusion plate having a diffusion angle. An LED-type light source device according to claim 1;
A spotlight body that houses the LED light source device;
A condensing lens that condenses the light from the LED light source device housed in the spotlight body and emits the light to the outside;
A spotlight comprising a moving mechanism for relatively changing a distance between the LED light source device and the condenser lens.

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