JP2012243420A - Lighting system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance light utilization efficiency in a lighting system with a solid-state light-emitting element and an optical member combined.SOLUTION: The lighting system 1 is provided with a light-emitting part 2 having a plurality of LEDs 22 arranged in rotational symmetry, a light distribution control part 3 having a plurality of lenses 32 each fitted to oppose to each LED 22, and a case 4 retaining the light distribution control part 3 in free rotation with a rotational symmetry axis L of the light-emitting part 2 as a center. The lighting system 1 is to vary a distance between the light distribution control part 3 and the light-emitting part 2 by rotating the light distribution control part 3. Each lens 32 includes a groove part 39 along a circumference of a circle going through each center of the lens 32 with the rotational symmetry axis L as the center on a surface of its LED 22 side. When the light distribution control part 3 and the light-emitting part 2 are made to approach each other, the LED 22 passes through the groove part 39, not to be in contact with the lens 32. With this, since the lens 32 can be arranged up to sideways of the LED 22, the light emitted from the LED 22 toward sideways is made incident to the lens 32, wherefore, light utilization efficiency can be enhanced.

Description

  The present invention relates to a lighting device that combines a solid light emitting element such as an LED (Light emitting diode) and an optical member.

  2. Description of the Related Art Conventionally, an illumination device is known that combines an LED and an optical member to change the light distribution angle of light to be irradiated (see, for example, Patent Documents 1 and 2). As shown in FIG. 14, such an illuminating device includes a light emitting unit 20 having a plurality of LEDs 10, a light distribution control unit 40 having a plurality of lenses 30 provided to face each LED 10, and a light emitting unit. 20 and a housing 50 that houses the light distribution control unit 40. The light distribution control unit 40 has a substantially cylindrical shape and has a male screw groove 41 on the outer periphery thereof. The housing 50 has a cylindrical shape with an upper surface opened, and has an internal thread groove 51 that is screwed into the external thread groove 41 on the inner periphery thereof. The housing 50 rotatably holds the light distribution control unit 40 by screwing the female screw groove 51 and the male screw groove 41 of the light distribution control unit 40. When the light distribution control unit 40 is rotated with respect to the housing 50, the distance between the LED 10 and the lens 30 changes. Therefore, the refraction pattern in the lens 30 of the light emitted from the LED 10 changes, and the light distribution angle of the light emitted from the illumination device changes.

JP 2004-221042 A JP 2007-299679 A

  However, in the illumination device as described above, the lens 30 and the LED 10 come into contact with each other when the lens 30 and the LED 10 are brought close to each other by rotating the light distribution control unit 40, so that the lens 30 is arranged to the side of the LED 10. Can not do it. Therefore, the light emitted from the LED 10 to the side thereof (indicated by a broken arrow) does not enter the lens 30 and the utilization efficiency of the light emitted from the LED 10 is low.

  The present invention solves the above-described problem, and in an illuminating device that controls the light distribution of irradiation light by rotating a light distribution control unit, the illuminating device that can increase the utilization efficiency of light emitted from a light source The purpose is to provide.

  The illumination device of the present invention includes a light emitting unit having a plurality of light sources arranged in a rotationally symmetric manner, a light distribution control unit having a plurality of optical members provided to face each of the plurality of light sources, and the light distribution. A housing that holds the control unit rotatably about the rotational symmetry axis of the light emitting unit, and the distance between the light distribution control unit and the light emitting unit is variable by rotating the light distribution control unit. Each of the optical members has a groove portion on a light source side surface of the member along a circumference of a circle passing through each center of the member with the rotational symmetry axis as a center.

  It is preferable that the light emitting unit and the light distribution control unit have a center light source and a center optical member at a position corresponding to the rotational symmetry axis.

  It is preferable that the center optical member does not have the groove.

  It is preferable that the housing has an elastic protrusion that stops the rotation operation of the light distribution control unit in a state where each of the plurality of light sources and each of the plurality of optical members are opposed to each other.

  According to the present invention, when the light distribution control unit is rotated and the optical member and the light source are brought close to each other, the light source passes through the groove of the optical member and does not contact the optical member, so that the optical member does not contact the light source. It can arrange | position to the side of a light source. Therefore, the light emitted from the light source to the side can also enter the optical member, and the utilization efficiency of the light emitted from the light source is improved.

The disassembled perspective view of the illuminating device which concerns on embodiment of this invention. The perspective view of the said illuminating device. The perspective view when the light distribution control part which comprises the said illuminating device is seen from diagonally downward. (A) is a bottom view of the light distribution control unit, (b) is a top view of the light distribution control unit. The side view of the said light distribution control part. Sectional drawing of the lens which comprises the said light distribution control part. The perspective view and the one part enlarged view of the housing | casing which comprise the said illuminating device. The top view of the said housing | casing. The top view of the said illuminating device. The top view of the said illuminating device when rotating the said light distribution control part. (A) is sectional drawing of the said illuminating device in the state which made the light emission part and the light distribution control part adjoin, (b) is a figure which shows the optical path of the light radiate | emitted from the light source in the state of (a). (A) is sectional drawing of the said illuminating device in the state which separated the light emission part and the light distribution control part rather than the said state, (b) is a figure which shows the optical path of the light radiate | emitted from the light source in the (a) state. (A) is sectional drawing of the said illuminating device in the state which separated the light emission part and the light distribution control part further from the said state, (b) is a figure which shows the optical path of the light radiate | emitted from the light source in the (a) state. . Sectional drawing of the conventional illuminating device.

  A configuration of a lighting device according to an embodiment of the present invention will be described with reference to FIGS. 1 to 9. This illumination device uses an LED as a light source.

  As shown in FIGS. 1 and 2, the lighting device 1 rotates the light emitting unit 2, the substantially disk-shaped light distribution control unit 3 provided on the light emitting surface side of the light emitting unit 2, and the light distribution control unit 3. A housing 4 that can be held and a heat dissipating unit 5 that dissipates heat generated in the light emitting unit 2 are provided. The light emitting unit 2 is attached to the inner bottom surface of the housing 4. The light distribution control unit 3 is held by the housing 4 at a position where the light emitted from the light emitting unit 2 enters. The heat dissipating part 5 has a plurality of plate-like fins 51 made of aluminum or copper having high thermal conductivity, and is fixed to the outer bottom surface of the housing 4.

  The light emitting unit 2 includes a disk-shaped wiring substrate 21 and a plurality of LEDs 22 serving as light sources arranged on the wiring substrate 21 in a rotationally symmetrical manner. The LED 22 includes a center LED 23 disposed at a position corresponding to the rotational symmetry axis L, and a plurality of peripheral LEDs 24 disposed at the periphery of the center LED 23. The peripheral LED 24 is arranged at a position corresponding to each vertex of a regular hexagon centering on the rotational symmetry axis L. Each of these LEDs 22 is composed of a white LED that emits white light. The optical axis of each LED 22 is parallel to the rotational symmetry axis L. The number of LEDs 22 mounted on the wiring board 21 and the arrangement of the LEDs 22 on the wiring board 21 are not limited to those of the present embodiment.

  The wiring board 21 is configured using a material having high thermal conductivity, for example, a metal such as aluminum, a resin such as glass epoxy, or an inorganic material such as ceramic as a base material. The wiring board 21 has a light reflecting member (not shown) having a high light reflectance on the LED 22 mounting surface. The light reflecting member is made of, for example, silver or aluminum. In addition, the wiring board 21 has a wiring pattern (not shown) for supplying power to the LEDs 22.

  The light distribution control unit 3 has a substantially disk-shaped lens array 31 (shown by dots) on a surface on which light from the LED 22 is incident. The lens array 31 is made of a translucent material such as acrylic resin, polycarbonate resin, silicone resin, or glass. The lens array 31 includes a plurality of lenses 32 provided to face the respective LEDs 22 and a flat portion located between the lenses 32. The lens 32 includes a central lens 33 that faces the central LED 23 and a peripheral lens 34 that faces the peripheral LED 24 (see also FIGS. 3 and 4 to be described later). The optical axis of each lens 32 coincides with the optical axis of the LED 22 facing each other.

  The lens array 31 is held by a substantially cylindrical lens holder 35. The lens holder 35 is made of, for example, a metal such as aluminum or a resin such as polyethylene terephthalate (PET). The lens holder 35 protrudes from a male screw groove 36 provided on the outer periphery thereof, a light distribution control unit positioning recess 37 provided in a direction substantially orthogonal to the male screw groove 36, and an end on the light emitting surface side. An annular convex portion 38. The depression 37 is provided at a position corresponding to the peripheral lens 34, and the elastic protrusion 42 of the housing 4 is fitted into the depression 37.

  The housing 4 has a cylindrical shape with an open upper surface and is made of a material having high thermal conductivity, for example, aluminum. The housing 4 has a female screw groove 41 on its inner periphery. The female screw groove 41 is screwed with the male screw groove 36 of the light distribution control unit 3. The housing 4 rotatably holds the light distribution control unit 3 by screwing the female screw groove 41 and the male screw groove 36 of the light distribution control unit 3. Moreover, the housing | casing 4 has the elastic protrusion part 42 for light distribution control part positioning on the side wall.

  The structure of the lens 32 constituting the light distribution control unit 3 will be described with reference to FIGS. As shown in FIGS. 3 to 5, each of the peripheral lenses 34 is a circle (indicated by a broken line in FIG. 4A) passing through the centers of the peripheral lenses 34 about the rotational symmetry axis L on the surface on the LED 22 side. A groove 39 along the circumference of (shown). The groove 39 prevents contact (interference) between the peripheral lens 34 and the peripheral LED 24 when the light distribution control unit 3 is rotated. The center lens 33 does not have the groove 39.

  As shown in FIG. 6, the lens 32 has a substantially inverted truncated cone shape with a small diameter on the LED 22 side, and has a recess 32 a on a surface on which light from the LED 22 is incident. The recess 32a is provided so as to surround the LED 22, and includes a first light incident surface 32b facing the LED 22 and a second light incident surface 32c constituting the side surface of the recess 32a. The lens 32 further includes a light reflecting surface 32d that totally reflects light incident from the second light incident surface 32c, and a light emitting surface 32e that emits light. 6 shows a cross-sectional view of the peripheral lens 34 having the groove 39, the center lens 33 has the same structure as the peripheral lens 34 except that the peripheral lens 34 is not provided.

  As shown in FIGS. 7 and 8, the elastic protrusion 42 of the housing 4 includes a vertical hole 43 provided on the side wall of the housing 4 and an elastic body 44 accommodated in the vertical hole 43. The elastic body 44 is made of stainless steel or the like, and is a leaf spring bent into a substantially V shape. This leaf spring is elastically mounted in the vertical hole 43 with its top portion protruding from the inner peripheral surface of the housing 4. In addition, the elastic body 44 may be comprised from materials other than stainless steel, and is not limited to a leaf | plate spring, For example, you may be comprised from the ball | bowl which has elasticity.

  As shown in FIG. 9, the elastic protrusion 42 is fitted into the recess 37 every time the light distribution control unit 3 rotates 60 degrees, and stops the rotation operation of the light distribution control unit 3. At this time, the light emitting unit 2 is attached to the housing 4 so that each lens 32 faces each LED 22. In FIG. 9, the illustration of the annular convex portion 38 is omitted.

  The lighting device 1 leads out a distribution line (not shown) electrically connected to the wiring pattern of the wiring board 21. This distribution line is connected to a light control device (not shown) provided with a switch, a microcomputer, and the like. The light control device is further electrically connected to a commercial power source (not shown), and controls the on / off control and the light control of the LED 22 by adjusting the power supply from the commercial power source to the LED 22.

  The operation of the lighting device 1 of the present embodiment configured as described above will be described with reference to FIGS. 10 to 13. The illuminating device 1 makes the distance between the light distribution control unit 3 and the light emitting unit 2 variable by rotating the light distribution control unit 3 around the rotational symmetry axis L. Specifically, the lighting device 1 causes the light distribution control unit 3 and the light emitting unit 2 to approach each other by rotating the light distribution control unit 3 clockwise with respect to the housing 4. Conversely, the lighting device 1 causes the light distribution control unit 3 and the light emitting unit 2 to be separated by rotating the light distribution control unit 3 counterclockwise with respect to the housing 4. At this time, the peripheral LED 24 passes through the groove 39 of the peripheral lens 34 and does not contact the peripheral lens 34 as shown in FIG. 10. On the other hand, since the center lens 33 is disposed at a position corresponding to the rotational symmetry axis, even if the light distribution control unit 3 is rotated, it is only rotated on the spot, and the relative position in the light distribution control unit 3 is determined. It does not change itself. Therefore, the center lens 33 does not contact the center LED 23 even if it does not have the groove 39.

  FIG. 11A shows a state in which the light distribution control unit 3 and the light emitting unit 2 are brought close to each other. At this time, most of the light emitted from the LED 22 is incident on the lens 32 because the lens 32 is disposed to the side of the LED 22 as shown in FIG. 11B (the optical path is indicated by a broken-line arrow). ). The light incident on the first light incident surface 32 b of the lens 32 is refracted there, and further refracted on the light emitting surface 32 e and then emitted from the lens 32. The light incident on the second light incident surface 32c is refracted there, then totally reflected by the light reflecting surface 32d, and further refracted by the light emitting surface 32e before being emitted from the lens 32. 11B shows the optical path in the peripheral lens 34 having the groove 39, the light is emitted in the same pattern also in the central lens 33. FIG.

  The movement of the light distribution control unit 3 in the direction of the light emitting unit 2 is such that the annular convex portion 38 of the light distribution control unit 3 contacts the upper end of the housing 4 before the light distribution control unit 3 contacts the light emitting unit 2. Since it is regulated by contact, the light distribution control unit 3 does not move in the direction of the light emitting unit 2 and does not damage the light emitting unit 2.

  FIG. 12A shows a state in which the light distribution control unit 3 and the light emitting unit 2 are separated from the state shown in FIG. 11A and the LED 22 is arranged at the focal position of the lens 32. At this time, the light emitted from the LED 22 is refracted (and totally reflected) by the lens 32 and emitted from the lens 32 as light parallel to the optical axis, as shown in FIG.

  FIG. 13A shows a state where the light distribution control unit 3 and the light emitting unit 2 are further separated from the state shown in FIG. At this time, the light emitted from the LED 22 is refracted (and totally reflected) by the lens 32 in a pattern different from the patterns shown in FIGS. 11B and 12B as shown in FIG. 13B. Is emitted from the lens 32.

  As described above, according to the lighting device 1 of the present embodiment, when the light emitting unit 2 and the light distribution control unit 3 are brought close to each other, the lens 32 is arranged to the side of the LED 22 without contacting the LED 22. Can do. Therefore, most of the light emitted from the LED 22 can be incident on the lens 32, and the utilization efficiency of the light emitted from the LED 22 is improved. Moreover, the light distribution angle of the irradiated light can be changed variously.

  Further, in the configuration having the center LED 23 and the center lens 33, the amount of light emitted from the illumination device 1 can be increased while effectively utilizing the space corresponding to the rotational symmetry axis L. Further, since the center lens 33 does not have the groove portion 39, more light emitted from the LEDs 22 can be incident on the lens than the peripheral lens 34.

  Moreover, if the wiring board 21, the housing | casing 4, and the flat fin 51 are comprised from the material with high heat conductivity, the heat | fever produced with light emission of LED22 can be thermally radiated | emitted efficiently to the external field. This makes it possible to prevent an abnormal temperature rise inside the lighting device 1, thereby extending the life of the LED 22 and ensuring a stable operation of the lighting device 1.

  Further, if a light reflecting member is provided on the LED 22 mounting surface of the wiring substrate 21, the light that has been returned to the inner direction of the lighting device 1 by being totally reflected by the light emitting surface 32 e of the lens 32 is reflected. The light can be reflected by the member and directed again toward the outside of the lighting device 1. Thereby, the light extraction efficiency of the illuminating device 1 can be improved.

  Further, when the light emitting unit 2 and the light distribution control unit 3 are separated from each other, a part of the light emitted from the LED 22 is incident on the lens 32 as shown in FIGS. 12 (b) and 13 (b). Instead, the light may directly enter the flat portion of the lens array 31. Since such light is not subjected to light distribution control by the lens 32, there is a possibility of causing uneven irradiation or glare. Therefore, a light diffusing material that diffuses light may be added to the flat portion, or an optical process may be performed to diffuse light to the flat portion. As a result, light incident on the flat portion can be diffused in various directions, so that irradiation unevenness and glare caused by light incident on the flat portion can be reduced. The processing performed on the flat portion is not limited to the above, and for example, a light shielding member that shields light may be provided, or an optical process that shields light may be performed. Thereby, since light is not emitted from the flat portion, it is possible to prevent the occurrence of uneven irradiation and glare.

  Note that the lighting device according to the present invention is not limited to the above-described embodiment, and various modifications can be made. For example, the lighting device of the present embodiment has the center LED and the center lens, but the lighting device does not necessarily have these center members. The center lens may have a groove. Further, the light source is not limited to the white LED, and may be composed of an LED that emits light of other colors, or may be composed of a light source such as an organic EL having a light emitting mechanism different from that of the LED. Also, the plurality of light sources need not all be the same, and may be composed of a plurality of types of light sources. Further, the optical member is not limited to the lens having the concave portion used in the present embodiment, and may be configured from a general convex lens, or may be configured from an optical member other than a lens such as a reflecting plate. In this case, the reflecting plate is, for example, an aluminum reflecting plate that has been subjected to drawing processing, or an aluminum film formed on the molded resin surface. Moreover, the optical member and the lens holder that constitute the light distribution control unit may be integrally formed.

DESCRIPTION OF SYMBOLS 1 Illumination device 2 Light emission part 22 Light source (LED)
23 Center light source (Center LED)
3 Light distribution control unit 32 Optical member (lens)
33 Optical member for center (center lens)
39 Groove 4 Housing 42 Elastic Protrusion L Rotational Symmetry Axis

Claims (4)

A light emitting unit having a plurality of light sources arranged in a rotationally symmetric manner;
A light distribution control unit having a plurality of optical members provided facing each of the plurality of light sources;
A housing that holds the light distribution control unit rotatably about the rotational symmetry axis of the light emitting unit,
The light distribution control unit is configured to vary the distance between the light distribution control unit and the light emitting unit by rotating the light distribution control unit,
Each of the optical members has a groove portion on a light source side surface of the member along a circumference of a circle passing through each center of the member with the rotational symmetry axis as a center.   The lighting device according to claim 1, wherein the light emitting unit and the light distribution control unit include a center light source and a center optical member at a position corresponding to the rotational symmetry axis.   The lighting device according to claim 2, wherein the central optical member does not have the groove.   The said housing | casing has an elastic protrusion part which stops rotation operation | movement of the said light distribution control part in the state in which each of these light sources and each of these optical members were made to oppose. The illuminating device according to claim 3.

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