JP4853252B2 - Lighting device - Google Patents

Description

  The present invention relates to a lighting device that can be used for a display device, a lighting fixture, and the like, and particularly relates to a lighting device using a light emitting device having a semiconductor light emitting element.

  For example, in a display lamp disclosed in Japanese Patent Application Laid-Open No. 2005-268166, in order to efficiently irradiate light from a light emitting element forward with no unevenness, a total reflection lens is disposed on the upper surface of the light emitting element and light from the light emitting element is disposed. In a display lamp that totally reflects on the peripheral wall of the total reflection lens and emits the light to the front of the total reflection lens, a transparent synthetic resin is placed between the light emitting element and the reflection lens in a frame that surrounds the periphery of the light emitting element. A convex lens part formed by raising and injecting in a convex shape from the upper part of the frame is provided. In this way, the light from the light emitting element is condensed by the convex lens that is raised in a convex shape, and is suitably irradiated toward the total reflection lens, thereby efficiently irradiating the light from the light emitting element in front of the total reflection lens without unevenness. It is described that it can be done.

Japanese Patent Laying-Open No. 2005-268166.

  However, there is a limit in the above lens system for further increasing the output. Usually, when using a lens system, the light source needs to be a point light source that is smaller than the lens diameter. Therefore, a light-emitting device on which one semiconductor light-emitting element is mounted is used. In order to increase the output, it is necessary to increase the size of the semiconductor light emitting device itself, but this is technically difficult and also increases in cost. Although it is easier to mount a plurality of semiconductor light emitting elements, the above-described lens system does not easily eliminate uneven light emission.

  Further, in the lens as described above, the shape of the convex lens is easily influenced by the injection amount of the transparent resin, the curing conditions, and the like, and it is difficult to form a convex lens having the same shape.

  Therefore, the present invention has been made in view of the above problems, and in a lighting device using a high-power light-emitting device equipped with a plurality of semiconductor light-emitting elements, light emission unevenness is reduced with a relatively easy structure. An object is to provide a lighting device.

  In order to achieve the above object, an illuminating device of the present invention is an illuminating device including a light emitting device having a semiconductor light emitting element and an optical lens having an exit surface that emits light incident from the light emitting device, and emits light. The apparatus has at least two or more semiconductor light emitting elements, and the optical lens is characterized in that the exit surface has a rough surface or a light diffusion member in the vicinity of the exit surface. Thus, even when a light-emitting device having a plurality of semiconductor light-emitting elements is used, a lighting device with little luminance unevenness and color unevenness can be obtained.

  In the illumination device according to claim 2 of the present invention, the optical lens is a collimator lens.

  According to the present invention, in a lighting device using a high-power light-emitting device equipped with a plurality of semiconductor light-emitting elements, unevenness in light emission can be reduced and a lighting device capable of more uniform light emission can be obtained.

  The best mode for carrying out the present invention will be described below with reference to the drawings. However, the form shown below illustrates the illuminating device for embodying the technical idea of the present invention, and the present invention does not limit the illuminating device to the following.

  Further, the present specification by no means specifies the member shown in the claims as the member of the embodiment. In particular, the dimensions, materials, shapes, relative arrangements, and the like of the components described in the embodiments are not intended to limit the scope of the present invention only to the extent that there is no specific description. It is just an example. It should be noted that the size and positional relationship of the members shown in each drawing may be exaggerated for clarity of explanation. Furthermore, in the following description, the same name and symbol indicate the same or the same members, and detailed description thereof will be omitted as appropriate. Furthermore, each element constituting the present invention may be configured such that a plurality of elements are constituted by the same member and the plurality of elements are shared by one member, and conversely, the function of one member is constituted by a plurality of members. It can also be realized by sharing.

  FIG. 1 shows an illumination device 100 in the present embodiment. 1A is a perspective view showing a lighting device, FIG. 1B is a partially cutaway perspective view of the lighting device of FIG. 1A, FIG. 1C is an exploded view for explaining the structure of FIG. 1A, and FIG. 1D is a cross-sectional view of FIG. is there.

  In this embodiment, the lighting device 100 includes a power feeding plate 105 on which the light emitting device 200 is placed, a base 107 on which the power feeding plate 105 is fixed by screws 104, and an optical lens provided on the light emitting surface side of the light emitting device 200. 102 and a cylindrical body 101 having an opening through which the optical lens 102 is exposed. The cylindrical body 101 and the base 107 are configured such that a screw provided on the lower inner wall of the cylindrical body 101 and a screw provided on the outer periphery of the base body 107 are combined.

  Specifically, the power feeding plate 105 is fixed on the base 107 with screws 104, and a wiring pattern is provided on the power feeding plate 105, and the light emitting device 200 is fixed so as to be conductive with the wiring pattern. Has been. A conducting wire 106 for electrical connection with the outside is joined to the power feeding plate 105, and the conducting wire 106 is provided so as to be drawn out from the opening of the base 107. The opening of the base into which the conducting wire 106 is inserted is provided by cutting out a part of the outer periphery of the base 107 and is cut out to a size that allows the conducting wire 106 to be accommodated. A part of the conductive wire 106 is covered by a single conductive wire cover 109 so that the pair of positive and negative conductive wires 106 are covered together. A protective member 108 is disposed between the conducting wire 106 penetrating the base 107 and the cylindrical body 101, thereby protecting the conducting wire 106 from being damaged when the cylindrical body 101 and the base 107 are screwed. Yes. Further, by cutting out a part of the outer periphery of the base 107, the conducting wire 106 can be pulled out from the side surface of the lighting device. Therefore, it can be attached to a flat place.

  An optical lens 102 is provided on the upper side (light emitting surface side) of the light emitting device 200 fixed to the power supply plate 105, and the optical lens 102 is provided via a spacer 103 so that the distance from the light emitting device 200 is constant. It is supposed to be. The spacer 103 is formed in a cylindrical shape along the inner wall of the cylindrical body 101, and the upper portion of the cylindrical body 101 and the upper portion of the spacer 103 hold a protruding portion provided on the upper portion of the optical lens 102. The optical lens is thus fixed, and the distance from the light emitting device 200 is constant. An opening is formed in the upper part of the cylindrical body 101, and the upper surface (outgoing surface) 102d of the optical lens 102 is exposed from this opening.

  The optical lens 102 is formed as a substantially paraboloid symmetric with respect to the rotation axis, and further has a recess 102a on the lower side. And this recessed part 102a and the light-emitting device 200 are arrange | positioned so as to oppose. A bottom surface 102b of the recess 102a is formed as an arc-shaped convex lens surface protruding toward the light emitting device, and an inner surface 102c between the bottom surface 102b and the outer peripheral surface of the optical lens is formed in a substantially cylindrical shape. With such a shape, light from the light emitting device is emitted as parallel light from the emission surface 102 d of the optical lens 102. In the present invention, the exit surface of the optical lens has a rough surface, or has a light diffusing member in the vicinity of the exit surface.

  When a collimator lens as shown in FIG. 1 is used as an optical lens, light from a light-emitting device that spreads in the propagation direction can be converted into parallel light having a uniform direction. Therefore, light can reach relatively far away. Such a lens is emitted as light in which the light state of the light emitting device as a light source is projected as it is. For example, when a light-emitting device having six semiconductor light-emitting elements as shown in FIG. 2 is used, uneven light on which six light spots are projected is emitted. As shown in FIG. 1, by making the emission surface of the optical lens (collimator lens) rough, it is possible to reduce the projection of the emitted light of the plurality of semiconductor light emitting elements as they are. The rough surface refers to a fine uneven surface, and can be obtained by a method such as forming a rough mold by molding or forming a rough surface by blasting after molding. Such a rough surface is preferably provided on the exit surface of the optical lens, whereby light can be diffused efficiently. If the side surface of the optical lens or the surface on which light from the light emitting device is incident (the bottom surface 102b or the inner surface 102c of the recess 102a in FIG. 1) is a rough surface, the light is diffused there and hardly reaches the exit surface 102d. This is not preferable because the efficiency of taking out to the outside decreases. It is preferable that almost the entire emission surface 102d be a rough surface, and it is preferable that the surface roughness be such that the haze (cloudiness value) is about 70 to 90%.

In addition, a diffusing member can be provided in the vicinity of the exit surface of the optical lens instead of the rough surface as described above. For example, light can be diffused by adding a diffusing agent such as SiO ₂ , TiO ₂ , or Al ₂ O _{3 in the} vicinity of the exit surface of the light diffusion film or optical lens.

  Moreover, light can be efficiently diffused by increasing the density of the rough surface having a higher density or the density of the diffusing member near the center of the light emitting surface. For example, as shown in FIG. 3, light emission is achieved by making a region facing the concave portion 302 a provided on the bottom surface of the exit surface of the optical lens 302, that is, the vicinity of the center of the exit surface a high-density rough surface. Light from the device can be diffused efficiently. Moreover, the surrounding area | region can also be made into the rough surface where a density is gradually low toward the outer peripheral part of an output surface.

  In the present invention, a rough surface is provided on the exit surface of the optical lens, or a light diffusing member is provided in the vicinity of the exit surface. The exit surface is substantially flat as shown in FIG. 1D. As shown in FIG. 4A, the exit surface side recess 402e can be provided on the exit surface facing the recess 402a provided on the bottom surface of the optical lens 402. The exit surface side recess 402e is provided in a region irradiated with light incident on the optical lens through the recess 402b, and is provided at an angle so as to be a reflection surface 402f capable of total reflection. . As shown in FIG. 4B, the light reflected here is totally reflected by the outer reflecting surface 402g provided on the side surface of the optical lens, and is emitted to the outside from the emitting surface 402d. By adopting such a shape, the shape pattern of the semiconductor light emitting element is not projected as it is, and uneven light emission can be reduced. Even in the optical lens having such a shape, light emission unevenness can be reduced by providing a rough surface on the exit surface 402d or providing a light diffusion member in the vicinity of the exit surface. The reflecting surface 402f and the outer reflecting surface 402g provided inside the exit surface side recess are preferably uniform so as to be totally reflective.

  FIG. 2 shows the light-emitting device in this embodiment. In the present embodiment, the package 201 of the light emitting device is made of resin, and has a recess 203 having a side surface and a bottom surface and having an upper surface as an opening. A lead terminal 202 is provided on the bottom surface of the recess 203 so as to be exposed as a conductive member. Further, some of the lead terminals are included in the package and extend so as to protrude from the side surface of the package 201. Thereby, it functions as a conductor wiring of a plurality of semiconductor light emitting elements 204 arranged in the package 201. The semiconductor light emitting element 204 and the protection element 205 are fixed on the lead terminal 202 by a die bond member such as resin or metal paste. The p electrode and n electrode of the semiconductor light emitting element 204 and the protection element 205 and the lead terminal 202 are electrically connected by a conductive wire. In addition, the recess 203 is filled with a sealing member such as a resin so as to cover them.

  The package 201 only needs to have a placement area on which a plurality of semiconductor light emitting elements, protection elements, and the like can be placed. For example, the package 201 may be a plate-like package provided with conductor wiring or a recess as shown in FIG. A package or the like can be used. The size of the light emitting portion of the package is preferably equal to or smaller than the light incident portion of the optical lens, and more preferably a circular light emitting portion.

In the present invention, a plurality of semiconductor light emitting elements are used, but the composition, wavelength, number, arrangement, etc. of each semiconductor light emitting element can be arbitrarily selected. For example, as blue and green light emitting elements, those using ZnSe or a nitride semiconductor (In _X Al _Y Ga _1- XYN, 0 ≦ X, 0 ≦ Y, X + Y ≦ 1) are used. it can. As the red light emitting element, GaAs, InP, or the like can be used. Furthermore, a semiconductor light emitting element made of a material other than this can also be used. The composition, emission color, size, number, and the like of the light emitting element to be used can be appropriately selected according to the purpose.

In the case of a light-emitting device having a fluorescent material, a nitride semiconductor (In _X Al _Y Ga _1- XYN, 0 ≦ X, 0 ≦ Y, X + Y ≦ 1) is preferable. Various emission wavelengths can be selected depending on the material of the semiconductor layer and the degree of mixed crystal. Further, a light-emitting element that outputs not only light in the visible light region but also ultraviolet rays and infrared rays can be obtained.

  The sealing member may contain a fluorescent member that emits light having a different wavelength by absorbing at least a part of the light from the semiconductor light emitting element as the wavelength converting member.

  As the fluorescent member, it is more efficient to convert the light from the semiconductor light emitting element into a longer wavelength. The fluorescent member may be formed of a single type of fluorescent material or the like, or may be formed of a single layer in which two or more types of fluorescent material are mixed, or contains one type of fluorescent material, etc. Two or more single layers may be stacked, or two or more single layers each of which is mixed with two or more kinds of fluorescent substances may be stacked.

  Any fluorescent member may be used as long as it absorbs light from a semiconductor light emitting device having a nitride semiconductor as a light emitting layer and converts the light to light of a different wavelength. For example, nitride phosphors / oxynitride phosphors mainly activated by lanthanoid elements such as Eu and Ce, lanthanoid phosphors such as Eu, and alkalis mainly activated by transition metal elements such as Mn Earth halogen apatite phosphor, alkaline earth metal borate halogen phosphor, alkaline earth metal aluminate phosphor, alkaline earth silicate, alkaline earth sulfide, alkaline earth thiogallate, alkaline earth silicon nitride At least selected from organic and organic complexes mainly activated by lanthanoid elements such as germanate or lanthanoid elements such as Ce, rare earth aluminate, rare earth silicate or Eu Any one or more are preferable. Moreover, it is fluorescent substance other than the said fluorescent substance, Comprising: The fluorescent substance which has the same performance, an effect | action, and an effect can also be used.

  Since the lighting device according to the present invention can be a lighting device with a simple structure and reduced light emission unevenness even when a high-power light-emitting device equipped with a plurality of semiconductor light-emitting elements is used, a flashlight, a spotlight It can also be used for various lighting devices such as downlights.

FIG. 1A is a perspective view showing an example of a lighting device according to the present invention. FIG. 1B is a partially cutaway perspective view of the lighting device of FIG. 1A. FIG. 1C is an exploded view for explaining the structure of FIG. 1A. FIG. 1D is a cross-sectional view of FIG. 1A. FIG. 2 is a perspective view showing an example of a light emitting device according to the present invention. FIG. 3 is a diagram illustrating a modification of the optical lens. FIG. 4A is a cross-sectional view showing a modification of the optical lens used in the illumination device according to the present invention. FIG. 4B is an explanatory diagram of light distribution characteristics of the optical lens of FIG. 4A.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100, 300 ... Illuminating device 101 ... Cylindrical body 102, 302, 402 ... Optical lens 103 ... Spacer 104 ... Screw 105 ... Feeding plate 106 ... Conducting wire 107 ... Base Base 108 ... Protective member 109 ... Cover 200, 400 ... Light emitting device 201 ... Package 202 ... Lead terminal 203 ... Concavity 204 ... Semiconductor light emitting element 205 ... Protective element

Claims (2)

A lighting device comprising: a light emitting device having a light emitting element; and an optical lens having an emission surface for emitting light incident from the light emitting device on the upper side of the light emitting device,
The exit surface has a reflection recess capable of light from the light emitting device,
The side surface of the optical lens includes a reflecting surface capable of reflecting light from the light emitting device to the emitting surface side, and light reflected by the concave portion provided above and outside the reflecting surface to the emitting surface side . An illuminating device comprising an outer reflective surface capable of reflecting.   The illumination device according to claim 1, wherein the optical lens has a rough surface on an exit surface.

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