JP5668980B2 - Light emitting device - Google Patents

Description

  The present invention relates to a light-emitting device that collects a light beam diffused and emitted from a light-emitting surface of a surface light source, and in particular, a matrix LED in which a plurality of LED (Light Emitting Diode) cells are arranged in a matrix is used as a surface light source. The present invention relates to a light emitting device.

  A light-emitting device that irradiates a certain surface using light emitted from a light source has been developed. In general, the light emitting device is configured by a lens system, a reflector system, or a combination thereof. In such a light emitting device, it may be required to focus the light beam on a dotted or linear region.

  For example, in the field where an image is printed with an ink that is cured with ultraviolet rays, it is required that the ultraviolet rays be condensed linearly on the surface of the paper on which the image is formed with the ink that is cured with ultraviolet rays.

  Patent Document 1 discloses a downlight having an elliptical elliptically reflecting plate, a light source lamp disposed in the inner space of the elliptically reflecting plate, and a substantially cylindrical body having a shape whose diameter decreases from the upper end toward the lower end as a whole. Is described. The substantially cylindrical body includes an auxiliary reflecting plate and a glare preventing portion that decreases in diameter downward from the lower end of the auxiliary reflecting plate.

  In Patent Document 1, light having reached the auxiliary reflector from the light source lamp is reflected toward the light source lamp by reducing the diameter of the substantially cylindrical body from the upper end to the lower end. As a result, the reflected light strikes the filament of the light source lamp, whereby the filament is heated and the luminous efficiency of the light source lamp is increased.

  However, the downlight as described in Patent Document 1 is intended to irradiate a limited area such as an indoor space, and is designed so that light does not enter the eyes directly. The irradiation range is a wide range where the size of the light source can be ignored. On the other hand, there are techniques described in Patent Documents 2 and 3 as techniques for improving the light collection efficiency of the light source.

  In Patent Document 2, a compound lens-shaped sealing portion that divides a plurality of light-emitting elements, parallel light that passes through the light of the light-emitting elements and travels straight and parallel light that travels in an oblique direction, and oblique parallel light that travels straight and parallel. A lens system composed of a collimator lens having a reflective and refractive surface that transforms into a lens is disclosed.

  Patent Document 3 describes an LED light emitting device in which a light emitting source and a light control cover, a reflective cover, and a lens with adjustable focus are arranged in front of the light emitting source. The light control cover and the reflection cover are spread toward the front of the light emitting source.

JP 2008-016417 A Japanese Patent Laid-Open No. 2007-200320 JP 2008-016341 A

  Usually, when a lens system such as a sealing body or a collimator lens is miniaturized, the ratio between the size of the lens system and the size of the light emitting surface of the light source becomes important. That is, when the size of the light emitting surface of the light source is very small relative to the size of the lens system, parallel light with high accuracy can be obtained. On the other hand, when the size of the light emitting surface of the light source is larger than the size of the lens system, divergent light is generated.

  Therefore, when a plurality of LEDs as described in Patent Document 2 are used, the chip size of the LED that becomes the light emitting surface with respect to a lens system such as a sealing body and a collimator lens becomes large.

  Therefore, with the technique described in Patent Document 2, divergent light is obtained. Therefore, it has been impossible to obtain light having a desired shape in the irradiation region. At the same time, there has been a problem that luminance unevenness and chromaticity unevenness due to the LED light source cannot be improved.

  Further, in the optical system described in Patent Document 3, the light beam reflected from the side surface of the light control cover and the light beam that reaches directly without reflection enter the same point on the light incident surface of the lens, and both light beams. Cannot be refracted into parallel light in the same direction.

  That is, an optical system in which the virtual image of the LED directly reflected on the optical axis and the LED reflected from the side surface of the light control cover is located away from the optical axis with respect to the lens is a single parallel beam. First, the illumination light reaching the illumination surface has a non-uniform spread of illuminance distribution, although it is a rotation target, and it is difficult to perform uniform illumination. Therefore, in any of the technologies described in any of the patent documents, it is difficult to focus the light beam diffused and emitted from the light emitting surface of the surface light source in a dotted or linear region.

  The present invention has been made in view of the above-described problems, and provides a light-emitting device capable of condensing a light beam diffused and emitted from a light-emitting surface of a surface light source in a dotted or linear region. Is.

  The light-emitting device of the present invention is a light-emitting device that illuminates a light-receiving object with a condensed light beam, and is composed of a surface light source that diffuses and emits the light beam, and a long-axis direction including a part of a substantially elliptical cross-sectional shape A reflective member having a reflective surface for emitting a light beam with the surface light source located near one end of the light source and the other end partially opened, and the reflective member disposed in a state where the other end in the major axis direction is inclined toward the surface light source side And a second support member that arranges the surface light source in a state where the light emitting surface faces the reflecting surface and is inclined in the direction facing the light receiving object.

  Therefore, in the light emitting device of the present invention, the light beam diffused and emitted from the light emitting surface of the surface light source is reflected by the reflecting surface of the reflecting member and emitted from the opening at the other end in the major axis direction. However, this reflecting surface is arranged by the first support member in a state where the cross-sectional shape is a part of a substantially elliptical shape and the other end in the major axis direction is inclined to the surface light source side, and the light emitting surface of the surface light source is the reflecting surface The second support member is disposed so as to be inclined in a direction opposite to the light receiving object and facing the object. For this reason, the light beam emitted from the surface light source and reflected by the reflecting surface can be condensed into a dot shape or a line shape.

  The various components of the present invention do not necessarily have to be independent of each other. A plurality of components are formed as a single member, and a single component is formed of a plurality of members. It may be that a certain component is a part of another component, a part of a certain component overlaps with a part of another component, or the like.

  In the light-emitting device of the present invention, the reflecting surface is formed by a first support member in a state where the cross-sectional shape is a part of a substantially elliptical shape and the other end in the major axis direction is inclined toward the surface light source, and the surface light source emits light. The second support member is disposed in a state where the surface faces the reflecting surface and is inclined in the direction facing the light receiving object. For this reason, the light beam emitted from the surface light source and reflected by the reflecting surface can be condensed into a dot shape or a line shape. Therefore, it is possible to irradiate the ink on the ink which is cured with ultraviolet rays while irradiating the ink, and to cure the ink in a short time.

It is a typical longitudinal section front view showing the structure of the light emitting device of the embodiment of the present invention. It is a typical disassembled perspective view which shows the assembly structure of a light-emitting device. It is a perspective view which shows the external appearance of matrix LED which is a surface light source. It is a typical vertical front view which shows the structure of the light-emitting device of the one modification. It is a typical vertical front view which shows the structure of the light-emitting device of another modification. It is a typical vertical front view which shows the structure of the light-emitting device of another modification.

  An embodiment of the present invention will be described below with reference to the drawings. The light emitting device 100 of the present embodiment is a light emitting device 100 that illuminates a light receiving object (not shown) with a condensed light beam RL, and diffuses the light beam RL as shown in FIGS. 1 and 2. The surface light source 110 that emits light and the reflective surface 121 that has a part of an elliptical cross-section, is located near one end in the long axis direction LD, and the other end is partially opened to emit the light beam RL. A reflecting member 120, a first support member 130 in which the long axis direction LD is inclined toward the surface light source 110, and the surface light source 110 with the light emitting surface facing the reflecting surface 121 and the light receiving target. And a second support member 140 disposed in a state of being inclined in a direction facing the object.

  More specifically, as shown in FIG. 3, the surface light source 110 includes a matrix LED in which a plurality of four LED cells 111 are arranged in a matrix. The reflecting member 120 has a partially opened upper end that is the other end in order to emit the light beam RL.

  As shown in FIG. 2, the reflecting member 120 has a reflecting surface 121 that is linearly continuous in a direction substantially orthogonal to the major axis direction LD and the minor axis direction SD, and near the lower end that is one end thereof. A plurality of surface light sources 110 are arranged in the continuous direction of the reflecting surface 121.

  In the light emitting device 100 of the present embodiment, the reflecting member 120 is composed of a pair facing in the left-right direction, and a plurality of surface light sources 110 are arranged in the continuous direction of each of the pair of facing reflecting surfaces 121.

  The reflection member 120 as described above can be formed of, for example, a stainless steel or aluminum thin plate having a high surface reflectance. The surface of the reflecting surface 121 of the reflecting member 120 may be covered with a reflecting film such as a metal film or a dielectric multilayer film. Thereby, reflection efficiency can be made high. Examples of the metal film include silver and aluminum.

  Examples of the dielectric multilayer film include titanium oxide, thallium oxide, silicon oxide, and magnesium fluoride. Further, the metal film or the reflective film may not be formed on the entire surface of the reflective surface 121, and may be partially or discontinuously formed.

  Furthermore, a protective film may be provided on the metal film. As a result, the metal film can be protected from the outside air and moisture. As the protective film, for example, a silicon oxide film, a multilayer reflection film made of silicon and titanium oxide, and the like can be given.

  The first support member 130 includes a main body end surface member 131, a reflection support plate 132, and the like. As shown in FIG. 1, the long axis direction LD is set with the reflection member 120 in a state where the long axis direction LD is inclined toward the surface light source 110 side. Are arranged in a state inclined at an angle of 86 ° inward from the horizontal line HL.

  As shown in FIG. 2, the second support member 140 includes a triangular protrusion at the center of the upper portion of the apparatus main body 141. As shown in FIG. 1, the surface light source 110 has a light emitting surface facing the reflecting surface 121. As a state inclined in the direction facing the light receiving object, the light emitting surface is arranged in a state inclined at 66 ° or the like from the horizontal line HL. The second support member 140 incorporates a driver circuit that drives a plurality of surface light sources 110 made of matrix LEDs and a cooling mechanism (not shown) for cooling.

  In the configuration as described above, in the light emitting device 100 of the present embodiment, the light beam RL that is diffused and emitted from the light emitting surface of the surface light source 110 is reflected by the reflecting surface 121 of the reflecting member 120 and is in the long axis direction LD. The light is emitted from the opening at the other end.

  However, the reflection surface 121 is arranged by the first support member 130 in a state in which the cross-sectional shape is a part of an ellipse and the long axis direction LD is inclined toward the surface light source 110, and the surface light source 110 reflects the light emitting surface. The second support member 140 is disposed in a state of facing the surface 121 and being inclined in a direction facing the light receiving object.

  For this reason, the light ray RL emitted from the surface light source 110 and reflected by the reflecting surface 121 can be condensed into a dot shape or a line shape. Therefore, it is possible to irradiate the light beam RL in a concentrated manner on an ink (not shown) that is cured with ultraviolet rays and cure it in a short time.

  Furthermore, the light emitted from the matrix LED 110 has a certain degree of luminance distribution and chromaticity distribution. However, in the light emitting device 100 according to the present embodiment, the light reflected by the reflecting surface 121 reaches the emitting portion from various directions, and emits light in which these lights are mixed.

  For this reason, the luminance distribution and chromaticity distribution in the light condensing unit are superimposed with the luminance distribution and chromaticity distribution of the light arriving from various directions. As a result, the luminance distribution and chromaticity distribution of the collected light beam RL can be made uniform.

  The inventor actually simulated the light emitting device 100 as described above. In the simulation, the minor axis of the reflecting surface 121 was 22 mm and the major axis was 45 mm. As described above, the reflecting surface 121 is arranged in a state where the major axis direction LD is inclined 70 ° inward from the horizontal line HL, and the surface light source 110 is arranged in a state where the light emitting surface is inclined from the horizontal line HL to 66 ° or the like. did.

  As the surface light source 110, an ultraviolet LED (NC-4U-134 manufactured by Nichia Corporation) in which four LED cells 111 are installed in a 2 × 2 matrix is assumed.

  It was confirmed that most of the light rays RL diffused and emitted from the matrix LED 110 were reflected by the reflecting surface 121 once and condensed linearly. The output at the condensing position is 4 W or more, and it was confirmed that the ultraviolet curable ink can be cured at high speed.

[Example]
When the inventor actually made a prototype of the light emitting device 100 as described above and confirmed it, it was confirmed that the error in the relative position between the reflecting member 120 and the surface light source 110 significantly affects the performance.

As an error that can be considered as a cause of an error in the relative position between the reflecting member 120 and the surface light source 110,
1. Positional relationship error between the housing of the surface light source 110 and the LED elements in the housing = ± 0.2 mm
2. Size error of housing of surface light source 110 = ± 0.2 mm
3. Error in soldering surface light source 110 to substrate (not shown) = ± 0.1 mm
4). Position error of solder land of surface light source 110 substrate = ± 0.1 mm
5. Assembly error between first support member 130 and second support member 140 = ± 0.1 mm
6). Assembly error between first support member 130 and reflection member 120 = ± 0.1 mm
Is assumed.

The error of the root mean square of the above errors is
Error = √ (0.2 ² +0.2 ² +0.1 ² +0.1 ² +0.1 ² +0.1 ² ) = 0.35
Therefore, an error of ± 0.35 mm may occur, which is unacceptable.

  Therefore, it is necessary to mount on the light emitting device 100 a mechanism that can adjust the relative position between the reflecting member 120 and the surface light source 110 by 0.35 mm or more, for example, 0.5 mm. For example, a spring is disposed between the surface light source 110 and the second support member 140, and the surface light source 110 is screwed to the second support member 140 at a plurality of positions on the outer peripheral portion. Is displaceable with respect to the second support member 140 (not shown).

  Further, a wedge-shaped spacer can be press-fitted between the surface light source 110 and the second support member 140 (not shown). The first support member 130 and the second support member 140 are supported by a micrometer head so as to be movable (not shown). By adopting the structure as described above, an error in the relative position between the reflecting member 120 and the surface light source 110 can be corrected.

  The present invention is not limited to the present embodiment, and various modifications are allowed without departing from the scope of the present invention. For example, in the above embodiment, the reflecting member 120 is composed of a pair facing in the left-right direction, and a plurality of surface light sources 110 are arranged in the continuous direction of each of the pair of facing reflecting surfaces 121.

  However, as shown in FIG. 4, there may be only one reflecting member 120, and the surface light source 110 may be opposed to the vicinity of the lower end thereof. Further, as shown in FIG. 5, even if a plurality of reflecting members 220 and a plurality of surface light sources 110 are arranged with a first support member and a second support member in a substantially short axis direction SD with the light receiving object as the center. Good. In this case, the luminance of the light beam RL condensed linearly can be improved.

  Furthermore, as described above, the structure in which the plurality of reflecting members 220 and the plurality of surface light sources 110 are arranged by the first support member and the second support member in the substantially short axis direction SD around the light receiving object is a concentric circle. It may be arranged in a shape.

  Further, in the above embodiment, as shown in FIG. 2, the reflecting member 120 has a reflecting surface 121 that is linearly continuous in a direction substantially orthogonal to the major axis direction LD and the minor axis direction SD, and is a lower end that is one end thereof. In the vicinity, a plurality of surface light sources 110 are illustrated as being arranged in the continuous direction of the reflecting surface 121.

  However, as shown in FIG. 6, the reflecting member 220 has a reflecting surface 221 that is continuous in a circle in a direction substantially orthogonal to the major axis direction LD and the minor axis direction SD, and the plurality of surface light sources 110 are reflecting surfaces. 221 may be arranged in a circular shape facing 221. In this case, since the light rays RL emitted from the plurality of surface light sources 110 are concentrated in a dot shape, the light rays RL can be condensed with high brightness in this dot shape.

  The reflecting member has a plurality of reflecting surfaces that are continuous in a polygonal shape in a direction substantially orthogonal to the major axis direction LD and the minor axis direction SD, and the plurality of surface light sources 110 are individually opposed to the plurality of reflecting surfaces. It may be arranged in the position to do. Also in this case, since the light rays RL emitted from the plurality of surface light sources 110 are concentrated in a point shape, the light rays RL can be condensed with high brightness in this point shape.

  Furthermore, in the said form, the reflection member 120 which has the reflective surface 121 which cross-sectional shape consists of a part of ellipse was illustrated. However, the reflecting surface does not have to be completely elliptical, and may be a shape slightly deformed from the elliptical shape (not shown).

Needless to say, the above-described embodiment and a plurality of modifications can be combined within a range in which the contents do not conflict with each other. Further, in the above-described embodiments and modifications, the structure of each part has been specifically described, but the structure and the like can be changed in various ways within a range that satisfies the present invention.
Hereinafter, examples of the reference form will be added.
<1>
A light-emitting device that illuminates a light-receiving object with a condensed light beam,
A surface light source that diffuses and emits the light beam;
A reflecting member having a reflecting surface in which the surface light source is located in the vicinity of one end in the major axis direction and the other end is partially opened and emits the light beam, the cross-sectional shape being a part of a substantially elliptical shape;
A first support member that arranges the reflecting member in a state in which the other end in the major axis direction is inclined toward the surface light source;
A second support member that arranges the surface light source in a state in which a light emitting surface faces the reflecting surface and is inclined in a direction facing the light receiving object;
A light emitting device.
<2>
<1> The light emitting device according to <1>, wherein the surface light source includes a matrix LED in which a plurality of LED (Light Emitting Diode) cells are arranged in a matrix.
<3>
The reflecting member is continuous in a straight line in a direction substantially orthogonal to the major axis direction and the minor axis direction of the reflecting surface,
The light emitting device according to <1> or <2>, wherein the plurality of surface light sources are arranged in a continuous direction of the reflecting surface.
<4>
The reflecting member is composed of a pair of opposed members,
The light emitting device according to <3>, wherein the plurality of surface light sources are arranged in a continuous direction of each of the pair of opposing reflecting surfaces.
<5>
The reflective member has a plurality of reflective surfaces continuous in a polygonal shape in a direction substantially orthogonal to the major axis direction and the minor axis direction,
The light emitting device according to <1> or <2>, wherein the plurality of surface light sources are arranged at positions individually facing the plurality of reflection surfaces.
<6>
The reflective member has a continuous circular shape in a direction in which the reflective surface is substantially orthogonal to the major axis direction and the minor axis direction;
The light emitting device according to <1> or <2>, in which the plurality of surface light sources are arranged in a circle facing the reflecting surface.
<7>
<1> to <6> in which a plurality of the reflection members and a plurality of the surface light sources are arranged in the substantially short axis direction around the light receiving object by the first support member and the second support member. The light emitting device according to any one of the above.
<8>
Any one of <1> to <7>, further including a target placement mechanism that places the light receiving object at a position where the light beam emitted from the surface light source and reflected by the reflection surface is collected. The light emitting device described.

DESCRIPTION OF SYMBOLS 100 Light-emitting device 110 Surface light source 111 LED cell 120 Reflective member 121 Reflective surface 130 First support member 131 Main body end surface member 132 Reflective support plate 140 Second support member 141 Device main body 220 Reflective member 221 Reflective surface HL Horizontal line LD Long axis direction RL Light beam SD minor axis direction

Claims (8)

A light-emitting device that illuminates a light-receiving object with a light beam,
A reflecting member having a reflecting surface that has a cross-sectional shape consisting of a part of an ellipse, one end of the ellipse in the major axis direction partially opens, and reflects light rays on the inner side of the ellipse;
A surface light source that is located near the other end in the major axis direction of the reflecting member and emits light from a light emitting surface;
Have
The reflecting member is inclined toward the surface light source in the major axis direction;
The light emitting surface of the surface light source is inclined in a direction facing the light receiving object while facing the reflecting surface,
A light emitting device that illuminates the light receiving object with a light beam condensed by reflecting the light beam emitted from the surface light source by the reflecting surface and emitting the light beam from the opening . The reflecting member is continuous in a straight line in a direction substantially orthogonal to the major axis direction and the minor axis direction of the reflecting surface,
The light emitting device according to claim 1, wherein the plurality of surface light sources are arranged in a continuous direction of the reflecting surface. The reflecting member is composed of a pair of opposed members,
The light-emitting device according to claim 2, wherein the plurality of surface light sources are arranged in a continuous direction of each of the pair of opposing reflecting surfaces. The reflective member has a plurality of reflective surfaces continuous in a polygonal shape in a direction substantially orthogonal to the major axis direction and the minor axis direction,
The light emitting device according to claim 1, wherein the plurality of surface light sources are arranged at positions individually facing the plurality of reflection surfaces. The reflective member has a continuous circular shape in a direction in which the reflective surface is substantially orthogonal to the major axis direction and the minor axis direction;
The light-emitting device according to claim 1, wherein the plurality of surface light sources are arranged in a circle facing the reflecting surface. The light emitting device according to any one of 5 to the claims 1 is placed and a plurality said reflecting member and a plurality of the surface light source substantially in the short axis direction around the light-receiving object. According to any one of the to structures in which a plurality of the reflecting member in the substantially short axis direction around the light-receiving object and the plurality of the surface light source is placed is 4 claims a concentric 6 Light receiving device. A first support member that arranges the reflecting member in a state in which the other end in the major axis direction is inclined toward the surface light source;
A second support member that arranges the surface light source in a state in which the light emitting surface faces the reflecting surface and is inclined in a direction facing the light receiving object;
The target deployment mechanism in which the light beam reflected by the reflection surface is emitted from the surface light source is disposed the light receiving object in a position to be focused, any one of claims 1 to 7 having the wo of al The light emitting device according to 1.

Images