JP5295070B2 - Lighting device and lighting device for signboard using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an illuminator covering a LED on a substrate with a lens and emits surface-light, which obtains a surface light source for radiating brightly and uniformly light from a plurality of light sources to a wide area. <P>SOLUTION: The illuminator 1 includes a substrate 2, a plurality of light-emitting elements 3 arranged on the substrate 2, and an optical lens 4 covering each light-emitting element 3. The optical lens 4 has a rotating body shape the rotary axis of which is a normal L of the substrate 2 passing through the gravity of polygon formed by connecting each gravity of each light-emitting element 3, wherein the optical lens 4 has: an incident plane 42 which light from each light-emitting element 3 is made incident on; a first emitting plane 43 emitting part of this incident light in the direction along the optical axis of each light-emitting element 3; a reflection plane 44 where the part of the incident light is reflected; and a second emitting plane 45 where this reflected light is emitted to an outer periphery of a rotating body to illuminate a diffuse reflection plane 21 on the substrate 2. Thus, since the light from the plurality of light-emitting elements become direct light from the first emitting plane 43 and indirect light from the diffuse reflection plane 21 to cause surface light emission, the surface light source for emitting light brightly and uniformly in a wide area is obtained. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an illuminating device that covers a light source such as a light emitting diode (LED) with an optical member and emits light, and an illumination device for a signboard using the illuminating device.

  2. Description of the Related Art Conventionally, lighting devices capable of surface light emission have been used for signboard lighting and the like. As such an illuminating device, there is an illuminating device in which a surface light source that irradiates light in a wide range is formed by reflecting and refracting light from a light source such as an LED by an optical member such as a lens and diffusing radiation (for example, patent Reference 1).

  Such an illumination device is shown in FIG. In the illumination device 100, one LED 102 and a rotating body-shaped lens 103 covering the LED 102 are mounted on a substrate 101 so that their optical axes coincide with each other. An inverted conical reflecting surface 131 having an optical axis as a central axis is formed. In this illuminating device 100, the light from the LED 102 is transmitted directly through the vicinity of the apex of the inverted cone of the lens 103 and the direct reflection light reflected by the reflecting surface 131, passes through the side surface of the lens 103, and the diffuse reflecting surface 111 of the substrate 101. It is irradiated as indirect light that is diffusely reflected. Thereby, the illumination device 100 forms a wide range of surface light sources.

  By the way, in such an illuminating device, when a plurality of LEDs are used for increasing the brightness and adjusting the light color, for example, as shown in FIG. 10A, each LED 102 is on the optical axis of the lens 103. Instead, they are arranged at substantially equal intervals around the optical axis. Therefore, the light from each LED 102 is almost totally reflected by the reflection surface 131, passes through the lens side surface, and is diffusely reflected by the diffusion reflection surface 111, so that it is hardly emitted from the front surface of the lens 103. For this reason, as shown in FIG. 10B, the difference in luminance between the diffuse reflection surface 111 around the lens 103 and the front surface of the lens 103 is large, the front surface portion of the lens looks like black dots, and the lens 103 and the diffuse reflection surface 111 are It is impossible to emit a uniform surface light over a wide area.

  As another example, a light source and a rotating body-shaped lens are arranged on a substrate so that their optical axes coincide with each other, and the light incident on the lens is totally reflected by a morning glory-shaped reflecting surface and is reflected from the lens side wall surface. An illuminating device that emits light is known (for example, see Patent Document 2). However, this illumination device, like the above-mentioned Patent Document 1, has little irradiation to the front of the lens when a plurality of light sources are arranged in the lens.

  Thus, in the illumination devices as shown in Patent Documents 1 and 2, since the optical lens is designed on the assumption that one light source is covered, when irradiating light from a plurality of LEDs, The transmitted light to the front of the lens is extremely reduced. Therefore, the light from the front surface of the lens is dark, the visibility from a distance is lowered, and it is difficult to obtain a uniformly bright surface light source with little luminance unevenness over a wide range, and it is particularly unsuitable for signboard illumination.

JP 2008-53660 A JP 2007-48883 A

  The present invention solves the above-described problem, and in a lighting device that covers a light source on a substrate with a lens and performs surface emission, a plurality of light sources are provided, and a uniformly bright surface light source with a small luminance unevenness is obtained over a wide range. It is an object of the present invention to provide a lighting device and a lighting device for a signboard using the same.

In order to achieve the above object, an invention according to claim 1 is a mounting substrate having a light reflecting surface, a plurality of light source portions distributed on the mounting substrate, and an optical device arranged to cover these light source portions. And the optical lens is rotated about the normal line of the mounting substrate that passes through the center of the virtual polygon that connects the centers of gravity of the plurality of light source units. A cylindrical cavity that covers the plurality of light source portions is formed on the bottom surface of the optical lens, and a concave portion having an inverted conical inclined surface is formed on the top surface of the optical lens, The central axes of these cavities and recesses are on the normal line, and the optical lens is formed of a top surface of the cavity and is parallel to the mounting substrate, and an incident surface on which light from each light source unit is incident. , formed on the inclined surface of the recess, the plurality of light source sections Consists bottom of the cylindrical recess whose central axis coincides with the optical axis of respectively, a first emission surface for emitting a portion of light incident from the incident surface in a direction along the optical axis of each light source, consists inclined surface of the concave portion, a reflecting surface for reflecting part of light incident from the incident surface, made from the outer peripheral surface of the rotating body, emits light that is reflected by the reflecting surface to the rotating body periphery And a second exit surface for illuminating the mounting substrate.

  According to a second aspect of the present invention, in the illumination device according to the first aspect, the first emission surface is a flat surface.

  According to a third aspect of the present invention, in the illumination device according to the first or second aspect, the first emission surface is roughened.

  A fourth aspect of the present invention is a signage lighting device in which a plurality of the lighting devices according to the first aspect are dispersed and arranged on a common mounting board, and the mounting board is a signboard.

  According to the first aspect of the present invention, the light from the plurality of light source units becomes direct light emitted from the first emission surface in the direction along the optical axis of each light source unit, and is reflected by the reflection surface to be second. Since it is emitted as indirect light that is emitted from the emission surface and reflected by the light reflecting surface of the mounting substrate, the entire optical lens and the light reflecting surface of the mounting substrate appear to emit light to the viewer. It is possible to obtain a uniform light source that is bright over a wide area.

  According to the invention of claim 2, since the first emission surface can be formed by plane processing, for example, when the first emission surface is additionally processed in the optical lens, or the first emission surface is not formed in the optical lens. When the first emission surface is processed according to the number of light emitting elements using the standard lens, the manufacture becomes easy.

  According to the invention of claim 3, since the emitted light from the first emission surface is diffused and the luminance distribution is made uniform, the luminance unevenness is reduced, which is more suitable for applications such as signboard illumination.

  According to the invention of claim 4, for a signboard, there is little unevenness in brightness, and it is bright and easy to see.

Sectional drawing of the illuminating device which concerns on the 1st Embodiment of this invention. The top view of the illumination device. (A) is the top view of the board | substrate in the modification of the said embodiment, (b) is sectional drawing of the board | substrate, (c) is sectional drawing of the light emitting module in the modification, (d) is a board | substrate in the modification. Sectional drawing of the state incorporating the light emitting module. The fragmentary perspective view of the illuminating device for signboards concerning the 2nd Embodiment of this invention. The partial side view of the lighting device for signboards. (A) is the figure which shows the illumination range of one illuminating device of the illuminating device for signboards, the front view of the illuminating device for signboards when the character "O" is illuminated and displayed by a plurality of illuminating devices, (b) is a conventional one The figure which shows the illumination range of one of these illuminating devices, and the front view of the illuminating device for signboards when the character "O" is illuminated and displayed by the illuminating device. Sectional drawing of the illuminating device which concerns on the 3rd Embodiment of this invention. The top view of the illumination device. Sectional drawing of the conventional illuminating device. (A) is sectional drawing of the other conventional illuminating device, (b) is a top view which shows how the irradiation light from the illuminating device looks.

(First embodiment)
Hereinafter, a lighting device according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 5. As shown in FIG.1 and FIG.2, the illuminating device 1 of this embodiment is the board | substrate (mounting board | substrate) 2 and the plurality (here 4 pieces) arrange | positioned disperse | distributed to the board | substrate 2 at appropriate intervals. The light emitting element (light source part) 3 and an optical lens 4 arranged so as to cover these light emitting elements 3 are provided. The optical lens 4 has a rotating body shape with the normal L of the substrate 2 passing through the virtual polygonal centroid connecting the centroids of the light emitting elements 3 as the rotation axis. This optical lens 4 has a cylindrical cavity 40 covering each light emitting element 3 formed on the bottom surface thereof, and a concave portion 41 having an inverted conical inclined surface formed on the top surface side. The central axes of the cavity 40 and the recess 41 are on the normal line L.

  The optical lens 4 is composed of an incident surface 42 made of the top surface of the cavity 40 and parallel to the substrate 2, and bottom surfaces of a plurality of cylindrical recesses 46 (described later) formed on the inclined surfaces of the recesses 41. A first emission surface 43 that emits a part of the light beam, a reflection surface 44 that is composed of an inclined surface of the recess 41 and reflects a part of light from the incidence surface 42, and an outer peripheral surface of the optical lens 4 that is formed from the reflection surface 44. A second emission surface 45 that emits the reflected light to the substrate 2. The cylindrical recess 46 is formed on the inclined surface of the recess 41 with the optical axis of the light emitting element 3 as the central axis.

  The substrate 2 is a general-purpose printed circuit board, which is excellent in dimensional stability and has little variation such as warpage and twist. The substrate 2 has a diffuse reflection surface (light reflection surface) 21 on the periphery of the optical lens 4 irradiated with the light emitted from the second emission surface 45. On the back of the substrate 2, an appropriate heat sink or the like (not shown) using a material with high heat dissipation such as copper is mounted in order to efficiently dissipate heat generated from the light emitting element 3. As the material of the substrate 2, for example, a glass epoxy substrate in which a glass cloth (cloth) is superimposed and impregnated with an epoxy resin is used. The material of the substrate 2 may be a metal base material. Further, the substrate on which the optical lens 4 and the light emitting element 3 are mounted and the substrate on which the diffuse reflection surface 21 is formed may be separated as long as they are parallel to each other.

  The diffuse reflection surface 21 is preferably one in which an acrylic or urethane white paint is sprayed on the substrate 2, but the total reflection factor is preferably about 80% or more and has a diffusion characteristic, but is not particularly limited thereto. Moreover, when the board | substrate 2 is made into a metal base material like stainless steel, you may paint on this and may affix a color sheet. The entire surface of the substrate 2 may be the diffuse reflection surface 21, or only the portion of the surface irradiated with the light reflected by the optical lens 4 may be the diffuse reflection surface 21. Moreover, the diffuse reflection surface 21 may be formed not on the board | substrate 2, but on another board | substrates, such as a main body board | substrate of a signboard, and a wall surface etc. to which the illuminating device 1 is attached, for example. Further, the shape of the diffuse reflection surface 21 is not particularly limited.

  The light emitting element 3 includes, for example, a blue LED, a YAG (Yttrium Aluminum Garnet) phosphor that converts light in a wavelength band of 380 nm to 480 nm into light of 480 nm to 780 nm, a BOS (Barium ortho-Silicate) phosphor, and the like. A white LED is used in combination with a sheet containing the same. Here, a plurality of light emitting elements 3 are arranged on the substrate 2 on a circumference around the rotation axis (corresponding to the normal L) of the optical lens 4 at substantially equal intervals. The light emitting element 3 may use LEDs of R, G, and B colors, and is not limited to the LEDs described above, and may be, for example, a small incandescent lamp or a small halogen bulb as long as it generates visible light. Etc. can also be used. The shape of the light emitting surface of the light emitting element 3 is not particularly limited, and may be embedded in the optical lens 4.

  In the optical lens 4, the cavity 40 has an opening diameter for accommodating a plurality of light emitting elements, and is fixed to the mounting surface of the substrate 2 in a state where each light emitting element 3 is covered with the cavity 40. The inclined surface of the recess 41 has a conical shape in which the distance from the substrate 2 increases linearly from the rotation axis (normal line L) of the optical lens 4 toward the outer periphery. It may be a convex curve. As the material of the optical lens 4, plastic such as polycarbonate, acrylic, silicon, epoxy, or glass is used. The optical lens 4 may be fixed to the substrate 2 with an adhesive or the like. However, a lens holder (not shown) for obtaining a desired light distribution by keeping the positional relationship between the light emitting element 3 and the optical lens 4 constant. And the lens holder may be fixed to the substrate.

  The cylindrical recess 46 has a cylindrical shape with a partly open side surface in which the optical lens 4 is dug from above the reflection surface 44 and a portion of the reflection surface 44 facing the bottom surface is opened. Each first emission surface 43 has a circular shape with a radius r with the optical axis of each light emitting element 3 as the central axis, and the outer periphery thereof is positioned substantially in contact with the reflection surface 44 (maximum depth d of the cylindrical recess 46). The light-emitting surfaces of the light-emitting elements 3 are opposed to each other. Here, the first emission surfaces 43 are positioned rotationally symmetrically with respect to the normal L at the same height from the inverted conical apex of the recess 41. In addition, each output surface 43 may be arrange | positioned so that the outer periphery may mutually cross the reflective surface 44. FIG.

  Each first emission surface 43 can change the amount of light in front of the lens depending on the size of the area, and can adjust the amount of light emitted from the front and rear of the lens. For example, when the front of the lens is brightened, the area of the first emission surface 43 is increased so as to cover the light emission surface of the light emitting element 3. That is, the first emission surface 43 is appropriately set so that the luminance balance between the light emitted from the light emitting element 3 from the first emission surface 43 and the light diffusely reflected by the diffusion reflection surface 21 is suitable. Can be designed to the required size.

  The reflection surface 44 corresponds to a portion of the inverted conical inclined surface of the concave portion 41 excluding the open surface by the plurality of cylindrical concave portions 46, and the direction of the reflected light is determined by the inclination angle with the optical axis of the optical lens 4. In other words, the diffuse reflection surface 21 can be widely irradiated, and the total reflection of the reflected light at the second emission surface 45 can be suppressed. Further, the reflecting surface 44 is an inclined surface that totally reflects the incident light from the light emitting element 3, but when the total reflection is insufficient, the surface is vapor-deposited or silver or aluminum as necessary. By processing by sputtering or the like, a reflectance of approximately 80 to 100% can be secured.

  The second emission surface 45 has a cylindrical shape perpendicular to the substrate 2, but is not limited to this, and depends on how much the optical lens 4 irradiates light on the diffuse reflection surface 21 of the substrate 2. In addition to the cylindrical shape, it can be configured as necessary.

  In the illumination device 1 of the present embodiment configured as described above, the light from the plurality of light emitting elements 3 is the light along the optical axis of each light emitting element 3 among the incident light from the incident surface 42. The direct light is transmitted through each first emission surface 43 parallel to the substrate 2 and irradiated as it is. Further, most of the light that does not follow the optical axis of each light emitting element 3 is reflected by the reflecting surface 44 and partly by the emitting surface 43, and is refracted and transmitted from the second emitting surface 45 to be emitted on the substrate 2. The periphery of the optical lens 4 is irradiated, diffusely reflected by the diffuse reflection surface 21, and becomes indirect light irradiated from the substrate 2. At this time, since the direct light from the lens front surface can be increased by the light emitted from the first light exit surface 43, the direct light can be brightened and the balance with the indirect light can be adjusted. It can illuminate without darkening. Accordingly, the viewer can see that the entire optical lens 4 and the diffuse reflection surface 21 are uniformly emitting light, so that a bright and uniform surface light source can be obtained over a wide area, for signboard illumination, etc. Suitable.

  In addition, since the first emission surface 43 can be formed by plane processing, for example, when the first emission surface 43 is additionally processed in the optical lens 4 or in the existing standard in which the first emission surface 43 is not formed in the optical lens 4. Manufacture is facilitated when the first emission surface 43 is processed according to the number of light emitting elements using a lens. Further, even if the position of the optical axis of the light emitting element 3 is shifted within the plane of the first emission surface 43, the light along the optical axis from the light emitting element 3 is emitted as it is, so that there is a margin in the placement accuracy of the light emitting element 3. Can hold.

  Moreover, since the light emitted from the first exit surface 43 can be diffused by making the flat surface of the first exit surface 43 into a rough surface, the luminance of the lens front surface can be made uniform. When the illumination device 1 is viewed, the luminance distribution of surface light emission can be made uniform, which is more suitable for applications such as signboards. Note that the optical lens 4 can be subjected to injection molding (injection molding) to allow the surface of the first emission surface 43 and a texture transfer for roughening the surface, and only the shape of the mold is changed. Since there is no change in the molding method of the lens, the material cost and the molding cost are not increased.

  In addition, since a plurality of light emitting elements 3 are housed and irradiated by one lens, a compact and bright surface light source can be obtained. Moreover, it can use for various illuminating devices, such as ceiling illumination and wall surface illumination, as planar illumination using the some illuminating device 1 besides the signboard illumination.

  With reference to Fig.3 (a)-(d), the modification of the illuminating device 1 of this embodiment is demonstrated. In this modification, the optical lens 4 and the light emitting element 3 are formed as a light emitting module 5 molded by a mold resin 51 and fixed to the substrate 2. As shown in FIGS. 3A and 3B, the substrate 2 has a lens insertion hole 22 through which the optical lens 4 is inserted, and a spring fixing hole 23 for fixing the light emitting module 5 to the substrate 2 with a spring member 52. And have.

  As shown in FIG. 3C, the light emitting module 5 includes an element substrate (for example, an LED substrate) 31 on which the light emitting element 3 is mounted, a flange portion 47 provided around the lower end of the optical lens 4, A mold resin 51 that surrounds the flange 47 and a spring member 52 attached to the bottom surface of the mold resin 51 are included. The spring member 52 has a hooking portion 53 for locking with the spring fixing hole 23 of the substrate 2.

  As shown in FIG. 3 (d), the light emitting module 5 inserts the upper portion of the optical lens 4 into the lens insertion hole 22 of the substrate 2 and inserts the hook portion 53 of the spring member 52 into the spring fixing hole 23 of the substrate 2. It is locked by. According to such a configuration, the positional accuracy of the arrangement of the optical lens 4 and the light emitting element 3 is improved, and attachment to and removal from the substrate 2 are facilitated.

(Second Embodiment)
Next, a signboard illumination device according to a second embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 4, a signboard illumination device 10 according to the present embodiment is configured such that a plurality of the illumination devices 1 according to the above-described embodiments are distributed on a common substrate 2. It is a signboard 20. As shown in FIG. 5, on the signboard 20, the illumination device 1 is a surface light source that is irradiated with direct light from the front surface of the optical lens 4 and indirect light from the diffuse reflection surface 21. Thereby, the whole signboard surface to which each illuminating device 1 is attached is illuminated brightly with uniform brightness over a wide range.

  FIG. 6A shows a case where the character “O” is illuminated and displayed using the plurality of lighting devices 1 by the sign lighting device 10 of the present embodiment, and FIG. Similarly, the case where the character “O” is illuminated and displayed using the illumination device 100 of FIG. In addition, the irradiation range of one illuminating device in this embodiment and the conventional one is shown on each upper side of these drawings. As shown in FIG. 6A, in the signboard illumination device 10 according to the present embodiment, a character (herein, the letter “O” in English) 11 or a logo as an aggregate of direct light from each first emission surface 43. The mark or the like is illuminated and the front surface of the lens is not darkened, and the indirect light from the substrate 2 illuminates the signboard 20 and enhances the visibility of the back portions of these characters and logo marks. That is, since each lighting device 1 is a surface light source with uniform brightness, characters, logo marks, and the like have little luminance unevenness when viewed from a distance and look bright and easy to understand. On the other hand, when the conventional lighting device 100 shown in FIG. 6B is used, the lens front portion of each lighting device 100 appears on the signboard 20 as a black dot, and the English letter “O” 12 has uneven luminance. As a result, the visibility is deteriorated and the appearance of the signboard 20 is impaired.

(Third embodiment)
Next, a lighting apparatus according to a third embodiment of the present invention will be described with reference to FIGS. In the illumination device 1 of the present embodiment, the plurality of first emission surfaces 43 (FIG. 1) in the optical lens 4 of the above embodiment are formed as an annular emission surface 48 formed of one continuous ring-shaped plane.

  The annular emission surface 48 is formed of a surface parallel to the substrate 2 in the step portion 49 of the step d formed stepwise along the circumference of the reflection surface 44 of the recess 41. The annular emission surface 48 is located at a predetermined height from the vertex of the inverted conical shape of the concave portion 41, and the outer periphery of the ring is on a circular plane having a radius R with the normal L of the substrate 2 as the central axis, The inner circumference is located on the circumference of the reflecting surface 44 of the recess 41. The optical axis of each light emitting element 3 is located on the circumference passing through substantially the middle of the ring width (difference between the outer periphery and the inner periphery) of the annular emission surface 48.

  According to the present embodiment, since the annular emission surface 48 is a common emission surface for the plurality of light emitting elements 3, the optical axis of each light emitting element 3 is simply disposed so as to pass through the ring range of the annular emission surface 48. Thus, the light can be emitted from the front surface of the lens, the degree of freedom of arrangement of the light emitting elements 3 is increased, and the influence of the light output due to the deviation of the optical axis of the light emitting elements 3 is small. Further, since the emission area can be increased over the ring, the number of the light emitting elements 3 can be increased accordingly, and therefore the first emission surface 43 does not need to be additionally changed. Further, since the annular emission surface 48 is not a plurality of local surfaces but a single surface, the surface machining operation is easy.

  In addition, this invention is not limited to the structure of the said various embodiment, A various deformation | transformation is possible suitably in the range which does not change the meaning of invention. For example, in the first and second embodiments, the first emission surface 43 and the annular emission surface 48 of the optical lens 4 are formed in a shape that is dug into the inclined surface, but a planar shape that protrudes from the inclined surface may also be used. Moreover, it is good not only as a plane but as a concave surface or a convex surface. Further, the second emission surface 45 of the optical lens 4 may be formed in a concave shape in which the distance from the substrate increases as the distance from the lens optical axis increases. In addition, the annular emission surface 48 in the second embodiment may be a plurality of rings.

1 Lighting device 2 Substrate (mounting substrate)
3 Light emitting element (light source part)
4 Optical lens 42 Incident surface 43 First exit surface 44 Reflective surface 45 Second exit surface 48 Annular exit surface (first exit surface)
10. Lighting equipment for signboards 20 Signboards (mounting substrates)
21 Diffuse reflective surface (light reflective surface)
L Normal

Claims (4)

An illumination device comprising: a mounting substrate having a light reflecting surface; a plurality of light source units arranged dispersedly on the mounting substrate; and an optical lens arranged to cover these light source units,
The optical lens, said a rotating body shape of normal line of the mounting substrate and a rotating shaft that passes through the virtual center of gravity of a polygon formed by connecting the center of gravity of each of the plurality of light source sections, the bottom surface of the optical lens A cylindrical cavity that covers the plurality of light source sections is formed, and a concave portion having an inverted conical inclined surface is formed on the top surface of the optical lens. On the line and
The optical lens is
An incident surface on which light from each light source unit is incident, which is composed of the top surface of the cavity and is parallel to the mounting substrate ;
Formed on the inclined surface of the concave portion, the bottom surface of a cylindrical concave portion having the optical axis of each of the plurality of light source portions as a central axis, and a part of the light incident from the incident surface is converted to the optical axis of each light source A first emission surface that emits in a direction along
A reflecting surface composed of an inclined surface of the recess, and reflecting a part of the light incident from the incident surface;
The made from the outer peripheral surface of the rotating member, the light reflected by the reflecting surface exits to the rotating body periphery, the lighting apparatus characterized in that it and a second emission surface for illuminating the mounting substrate . The lighting device according to claim 1, wherein the first emission surface is a flat surface orthogonal to the optical axis .   The lighting device according to claim 1, wherein the first emission surface is roughened. 請 plurality of illumination apparatus according to Motomeko 1 is arranged on a common mounting substrate dispersed with each other, billboard lighting device to which the mounting board is characterized in that it is a sign.