JP5320599B2 - Light source device and surface illumination device using the light source device - Google Patents

Description

  The present invention relates to a light source device and a surface illumination device using the light source device. More specifically, the present invention relates to a light source device capable of emitting substantially uniform illumination light using a highly directional point light source as a light source, and a surface using the light source device. The present invention relates to a lighting device.

  In recent years, lighting devices that use highly directional point light sources such as light-emitting diodes (hereinafter referred to as LEDs) and laser diodes (hereinafter referred to as LDs) have been developed in place of incandescent and fluorescent lamps. It is starting to be used for devices. LED has excellent features such as power saving, long life, and small size compared with incandescent bulbs and fluorescent lamps, etc., but the lighting area is extremely narrow due to its strong directivity, and its light Directly looking at the light causes a problem such as damaging the eyes. Therefore, a technique for efficiently diffusing this light is required for use as illumination light. Therefore, in order to use such a point light source as illumination light, an illuminating device with various contrivances has been proposed. (For example, refer to Patent Documents 1 and 2 below).

  For example, Patent Document 1 described below describes a surface light emitting device in which a light control unit that controls light from an LED is attached to the LED so that planar light can be obtained.

  The surface light emitting device includes an LED, a rectangular parallelepiped case in which the LED is accommodated, a light control unit that is attached to the outer surface of the lens of the LED, and a diffusion panel that covers the opening of the case, and the case includes a reflector therein. A plurality of LEDs are arranged at a predetermined interval on the bottom of the reflector, light control means are mounted on each of the LEDs, and the opening of the case is covered with a diffusion panel. It has become. The light control means reflects and transmits the light of the LED, and is provided at a position corresponding to the central portion of the LED so that the reflection amount is larger than the light transmission amount, and is provided around and reflects the reflection main portion. The reflection / transmission part has a light transmission amount larger than that of the main part, and a holder part provided in the reflection main part.

  Patent Document 2 below describes a surface illumination light source device and a surface illumination device using this surface illumination light source device.

  This surface illumination light source device includes an LED, a bottom casing provided with the LED in the center, a side surface erected from the periphery of the bottom and a box-shaped casing provided with an opening on the side facing the bottom, An optical reflector that covers the opening and makes the light from the LED substantially uniform. In addition, the surface illumination device uses a plurality of the surface illumination light source devices, and connects the plurality of surface illumination light source devices.

  In addition, when a plurality of surface illumination light source devices are connected in this manner, the connection portion becomes dark. Therefore, a surface illumination device in which a side wall hole is provided in the side wall portion of the connection portion is also disclosed in, for example, Patent Document 3 below. . The side wall hole communicates with the opening. The following Patent Documents 2 and 3 relate to the application of the applicant of the present application.

JP 2004-6317 A (paragraphs [0020] to [0026], FIG. 1) JP 2008-27886 (paragraphs [0045] to [0048], FIG. 1) JP 2009-110696 A (paragraphs [0045] to [0048], FIG. 8)

  Each of the surface light-emitting devices and surface illumination devices disclosed in Patent Documents 1 to 3 has a configuration in which a plurality of light source devices are brought into close contact with each other without a gap. These surface illuminators will increase the area of the light-emitting surface, that is, if the illumination area is expanded, the number of light source devices will be increased. As a result, the area of the light emitting surface cannot be expanded for the increased cost of the added part. That is, the area of the light emitting surface is the sum of the areas of the light emitting surfaces of the additional light source devices and does not exceed that. In addition, it is conceivable that a predetermined gap is provided between adjacent light source devices without close contact, but if this is done, the gap portion becomes dark and this dark portion is reflected on the diffusion plate and dark stripes appear on the light emitting surface. In order to eliminate this, the diffusion plate disposed above the light source device must be made high, that is, the distance from the light emitting surface must be increased. As a result, problems such as the height of the surface illumination device appear, and even the surface illumination device of Patent Document 3 cannot solve this problem. In addition, in the surface light-emitting device of the said patent document 1, since it becomes expansion of the rectangular parallelepiped case which accommodated the reflector, the expansion which adjusted the number of LED cannot be performed.

  Further, in recent years, light source devices using LEDs have features such as power saving, long life, and small size, reflecting the characteristics of LEDs as they are, and their uses are only used as described in Patent Documents 1 to 3 above. Instead, it may be used by directly incorporating it into a vending machine or a large game machine. However, when directly incorporated in such a device, the light source device has only one light-emitting surface, that is, the upper surface. Therefore, if the illumination area is limited and illumination to the surrounding area is necessary, Such a light source device cannot be used.

  The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to provide a light source device that can be used for many purposes by allowing illumination light to be emitted from multiple surfaces. It is in.

  Another object of the present invention is to provide an inexpensive surface illumination device that can obtain uniform illumination light in a large area without increasing the thickness of the surface illumination device, that is, the height from the light source, using the light source device. To do.

  In order to achieve the above object, the invention according to claim 1 is a point light source having strong directivity, a housing bottom plate provided with the point light source, and a housing side plate erected at a predetermined height from the periphery of the housing bottom plate. And a housing in which an opening is provided on the side facing the housing bottom plate and an inner wall surface is formed as a reflecting surface, and an optical reflecting plate that covers the opening and emits light from the point light source as substantially uniform illumination light. In the light source device, the side plate of the housing is at least a part of the side plate of the housing, and a side central reflection portion having a high light reflectance and a low light transmittance in the side plate region closest to the point light source and the side central reflection. In the outer side plate region of the portion, a side outward reflecting portion is formed in which the light reflectance decreases and the light transmittance increases as the distance from the side central reflecting portion increases.

  The invention according to claim 2 is the light source device according to claim 1, wherein the housing has at least one of the housing side plates standing from the periphery of the rectangular shape, wherein the housing bottom plate has a rectangular shape. The side central reflection part and the side outward reflection part are formed on a housing side plate.

  The invention according to claim 3 is the light source device according to claim 1 or 2, wherein the side central reflecting portion is formed by a groove or fine hole formed by half-cutting the housing side plate, and The side reflection portion is formed by a through-hole penetrating the housing side plate and having a predetermined opening area.

  According to a fourth aspect of the present invention, in the light source device according to the first aspect, the point light source is a light emitting diode or a laser diode.

  In order to achieve the above object, a surface illumination device according to a fifth aspect of the present invention includes the light source device according to any one of the first to fourth aspects, an opening, and one or more light source devices. A storage case having a size and a diffusion plate covering the opening, the storage case standing from the periphery of the case bottom plate having a larger area than the total bottom area of the number of the light source devices to be stored. A case side plate that is higher than the housing side plate of the light source device, and a box body that has the opening on the side facing the case bottom plate and has an inner wall surface formed of a reflective surface, and the light source device is disposed inside A gap (D1) for emitting illumination light is provided between the inner wall surface and the inner wall surface.

  The invention according to claim 6 is the surface illumination device according to claim 5, wherein the case side plate is inclined outwardly from a flat surface of the case bottom plate in a range of 90 ° to 150 °. It is characterized by.

  The invention according to claim 7 is the surface illumination device according to claim 5 or 6, wherein the housing case houses a plurality of the light source devices, and the adjacent light source devices are predetermined to each other. The diffusion plate is arranged with a predetermined gap (D3) from each of the optical reflection plates of the plurality of light source devices.

  The invention according to claim 8 is the surface illumination device according to claim 7, wherein the gap (D2) is equal to or more than one half of the maximum distance (W) between the opposed plates of the light source device. (D1) is not less than 1/2 of the gap (D2), and the interval (D3) is not more than 1/2 of the distance (D2).

  According to the first and second aspects of the present invention, the light from the point light source can be emitted substantially uniformly not only from the optical reflection plate surface but also from the side plate surface of the housing. As a result, the light emitting surface is multifaceted and the light emitting area is expanded, so the lighting area can be expanded by using it in a surface lighting device, and it can be directly incorporated into equipment such as vending machines and large game machines, Can also be expanded.

  According to the invention of claim 3, the side central reflecting portion is formed by a groove or a fine hole obtained by half-cutting the side plate, and the side outer reflecting portion is a through hole having a predetermined opening area that penetrates the side plate. Since it is formed, the side central reflecting portion and the side outward reflecting portion can be easily created.

  Further, according to the invention of claim 4, even when a highly directional point light source such as an LED or LD is used, a bright spot is not left in the central portion, and conversely, the portion directly above is darkened. Therefore, uniform illumination light can be obtained.

  Moreover, according to the invention which concerns on Claim 5, the effect of the light source device which concerns on the said each Claim 1-4 can be show | played, and it has a wider area by arrange | positioning a several light source device further. In addition, it is possible to obtain a surface illumination device that can obtain illumination light having a uniform illuminance distribution.

  According to the invention of claim 6, the case side plate is inclined outward, so that the area of the case opening becomes larger than that of the case bottom plate, and the light emitted from the side of the light source device is efficiently accommodated in the case. It can be reflected toward the opening.

  Further, according to the inventions according to claims 7 and 8, since the surface illumination light source device is not disposed adjacent to the housing case, a smaller number of point light sources are used while minimizing the decrease in luminance. Thus, uniform illumination light can be obtained on a large screen.

FIG. 1 is an exploded perspective view of a light source device according to Embodiment 1 of the present invention. 2 shows an optical reflecting plate constituting the light source device of FIG. 1, FIG. 2A is a top view, and FIG. 2B is a top view of a modification of the optical reflecting plate. 3 shows an optical reflecting portion of the side plate constituting the light source device of FIG. 1, FIG. 3A is a side view of FIG. 1, and FIGS. 3B to 3D are side views of modifications of the optical reflecting portion of the side plate. FIG. 4 is a schematic top view of a surface illumination device according to Embodiment 2 of the present invention. FIG. 5 is a cross-sectional view of the surface illumination device of FIG. 4 taken along line VV. 6 is a cross-sectional view showing a modification of the surface illumination device of FIG. FIG. 7 shows a modification of the surface illumination device of FIG. 4, and FIGS. 7A and 7B are schematic top views of the modification of the surface illumination device. 8A is a cross-sectional view taken along line VIIIA-VIIIA in FIG. 7B, and FIGS. 8B and 8C are side views of the optical reflecting portion provided on the side plate. 9 shows a light source device and a surface illumination device using the light source device according to Embodiment 3 of the present invention, FIG. 9A is a schematic top view, FIG. 9B is a side view of the surface illumination device of FIG. 9A, and FIG. It is sectional drawing in the IXC-IXC line | wire of FIG. 9A. 10 shows a modification of the surface illumination device of FIG. 9A, FIG. 10A is a top view, and FIG. 10B is a cross-sectional view taken along line XB-XB of FIG. 10A.

  Embodiments of the present invention will be described below. However, the embodiment shown below exemplifies a light source device for embodying the technical idea of the present invention and a surface illumination device using the light source device, and the present invention is specified to these. And is equally applicable to other embodiments within the scope of the claims.

  With reference to FIG. 1, the outline | summary of the light source device which concerns on Embodiment 1 of this invention is demonstrated. FIG. 1 is an exploded perspective view of the light source device according to Embodiment 1 of the present invention.

  The light source device 1 includes a point light source 2, a box-shaped housing 3 in which the point light source is provided on the bottom plate and opened upward, and an optical reflector that covers and opens the housing and reflects and transmits light from the point light source 2. 4.

  As the point light source 2, one LED, an LED in which a plurality of LED elements are assembled (hereinafter collectively referred to as an LED), or an LD is used. The LED may be not only the three primary colors of R, G, and B, but also other colors of LEDs, or an LED or LD with a lens attached. In this embodiment, an example using LEDs will be described.

  The housing 3 includes a housing bottom plate 3a to which the LED 2 is fixed at a substantially central portion, housing side plates 3b to 3e erected at a predetermined height from the periphery of the housing bottom plate, and an opening 3f provided on the side facing the housing bottom plate. The inner wall surface is formed of a reflective surface. The outer wall surfaces of the housing side plates 3b to 3e are also preferably reflective surfaces. When the outer wall surface is used as a reflection surface, when the surface lighting device is manufactured using the light source device 1, the LED light is reflected between the inner wall surface of the housing case of the surface lighting device and is efficiently directed to the diffusion plate side. The light can be emitted. This surface illumination device will be described later. The housing 3 is formed of a reflecting plate material having a high light reflectance, a low light transmittance, and a low light absorption rate, for example, an ultrafine foamed light reflecting plate. These ultrafine foamed light reflecting plate materials include those having a light reflectance of 98%, a light transmittance of 1%, and a light absorption of 1%, and these are preferably used. Of course, the housing is not limited to this material, and a transparent substrate may be used and a reflective material may be applied or printed on the substrate. For example, titanium white fine particles emulsified or polytetrafluoroethylene fine particles emulsified are formed by coating or screen printing.

  The housing bottom plate 3a has a substantially square shape with a side length of L1 (for example, 200 mm), and an exposure hole for exposing the light emitting portion of the LED 2 is formed at a substantially central portion thereof. The LED 2 is fixed to an unillustrated mounting board, and the mounting board is disposed on the back side of the bottom plate to expose the light emitting portion of the LED from the exposure hole. The housing side plates 3b to 3e are formed of vertical plates standing up to a predetermined height h1 (for example, 15 mm) from the periphery of the substantially square bottom plate 3a. That is, the side plates 3b to 3e are formed by four vertical plates. Although the housing side plate is vertical, it may be inclined at a predetermined angle from the periphery of the housing bottom plate 3a. The inclination angle is preferably more than 90 ° and within 150 ° with respect to the plane of the housing bottom plate 3a. When inclined, the opening can be enlarged, and LED light can be efficiently emitted to the opening side using the inclined surface. The four housing side plates 3b to 3e are all or one or several housing side plates formed with optical reflecting portions for emitting LED light substantially uniformly toward the outer surface of the housing side plate. The configuration of this optical reflection unit will be described later.

  With reference to FIG. 1 and FIG. 2, the optical reflector attached to the opening of the housing will be described. 2 shows an optical reflector constituting the light source device of FIG. 1, FIG. 2A is a top view, and FIG. 2B is a top view of a modification of the optical reflector.

  As shown in FIGS. 1 and 2A, the optical reflection plate 4 is formed of a square plate having a size that covers the opening 3f of the housing 3. The optical reflecting plate 4 is formed of a square plate having a predetermined thickness and the same side length L1. That is, the opposing sides 4a, 4b and 4c, 4d have the same length. The optical reflector 4 is provided with a central reflecting portion 5A at the center and an outer reflecting portion 5B around the central reflecting portion, and has high light reflectance, low light transmittance and low light absorption. It is formed of a reflector, for example, an ultrafine foamed light reflector. Among these ultrafine foamed light reflecting plate materials, those having a light reflectance of 98%, a light transmittance of 1% and a light absorption of 1% are preferable.

  The central reflecting portion 5A is located in a portion directly above the LED 2 when the optical reflector 4 is attached to the opening 3f of the housing 3, and has a small area central reflecting area 5a facing a portion directly above the LED light emitting portion. The center reflection area 5a is centered on the center reflection area 5a, and the area around the center reflection area 5b is slightly enlarged at a predetermined distance from the center. The LED 2 irradiates the center reflection area 5a with the strongest light due to its light distribution characteristics, and then irradiates the center periphery reflection area 5b with the next strongest light. Therefore, the central reflection area 5a has the highest light reflectance and the lowest light transmittance, and the central peripheral reflection area 5b is adjusted so that the light reflectance is slightly lowered while the light transmittance is slightly increased. Yes. Since the reflectance of the central reflection area 5a is the highest and the light transmittance is the lowest, the area can be kept dark and the generation of a bright illumination spot can be eliminated.

  The light reflectance and light transmittance are adjusted by processing the reflecting plate. In the central reflection area 5a, the light reflectance and light transmittance are adjusted by adjusting the thickness of the narrow groove group consisting of a plurality of fine grooves (vertical grooves, horizontal grooves, and ring shapes) or the plate thickness in the reflection plate material. The Further, in the central and peripheral reflection area 5b, the light reflectance and light transmittance are adjusted by providing a group of micro holes composed of a plurality of micro holes (through holes having a diameter of, for example, 1.0 mm or less).

  The outward reflecting portion 5B is formed of a plurality of through holes 51 to 53 having different opening areas arranged with a predetermined regularity from the central peripheral reflecting area 5b toward the sides 4a to 4d. The openings of the through holes 51 to 53 have a small opening area of the through hole 51 closest to the center peripheral reflection area, and the opening areas increase in order of the through holes 52 and 53 as the distance from the center peripheral reflection area increases. The through hole having these openings is formed at a location where a parallel line parallel to the side 4a and a vertical line parallel to the side 4b perpendicular to the side 4a intersect. That is, the openings of these through holes are arranged with regularity in an orthogonal lattice pattern at equal intervals.

  The optical reflecting plate 4 has through holes having predetermined openings at the four corners. When openings are provided at the corners, the surface lighting device is placed at the corners when the optical reflecting plate 4 is assembled in a surface lighting device to be described later. It turned out to be a little dark at the corresponding part. Therefore, in the optical reflecting plate 4A, as shown in FIG. 2B, openings are not provided in predetermined areas of these corners 6. By not providing the opening at the corner, more reflected light is emitted from the optical reflecting portion of the side plate corresponding to the corner, and the above inconvenience is solved.

  The material of the optical reflector is an ultra-fine foamed light reflector, but is not limited to this material, and a transparent substrate may be used, and a reflector may be applied or printed in addition to the opening portion of the substrate. Good. For example, titanium white fine particles emulsified or polytetrafluoroethylene fine particles emulsified are formed by coating or screen printing.

  Next, with reference to FIG. 3, the optical reflection part formed in a side plate is demonstrated. 3 shows an optical reflecting portion of a side plate constituting the light source device of FIG. 1, FIG. 3A is a side view of FIG. 1, and FIGS. 3B to 3D are side views of modified examples of the optical reflecting portion.

  Each of the four housing side plates 3b to 3e is formed with an optical reflecting portion 7A. The optical reflecting portion 7A is opposed to the LED 2 and is formed in a side central reflecting portion 7a formed in an area closest to the LED, and a side formed in an area extending in the longitudinal direction from the side central reflecting portion. It consists of the outward reflection part 7b. The side center reflecting portion 7a is formed of a plurality of fine holes so as to reflect the light emitted from the LED with a high light reflectance, and to have a low light transmittance. The side outward reflecting portion 7b is formed as a through hole having an opening that gradually reduces the light reflectance and increases the light transmittance as it moves away from the side central reflecting portion 7a. These fine holes and through holes are formed by substantially the same method as the central reflecting portion 5A and the outer reflecting portion 5B of the optical reflecting plate 4. The optical reflecting portion 7A may be rough (coarse) without being elaborate compared to the optical reflecting plate 4. The reason is that, from the light distribution characteristics of the LED 2, the irradiation light to the housing side plate is weaker than that just above the LED.

  The optical reflecting portion is not limited to the optical reflecting portion 7A, and various changes may be made. The optical reflecting portion 7B is formed by forming the side central reflecting portion 7a1 and the side outward reflecting portion 7b2 with slits, and the areas of these slits are changed so as to have a predetermined aperture ratio (FIG. 3B). reference). The optical reflecting portion 7C is configured such that a slit is not provided in the side central reflecting portion 7a2, and a relatively long slit having an opening area enlarged in the longitudinal direction is provided in the side outer reflecting portion 7b2 (FIG. 3C). reference). The optical reflecting portion 7D is configured such that the side central reflecting portion 7a3 is not provided with a notch, and the side outward reflecting portion 7b2 is provided with a wide notch as it goes in the longitudinal direction (see FIG. 3D). .

  In the present embodiment, the optical reflecting portion is provided on each of the four housing side plates 3b to 3e. However, according to the necessity of illumination light from the side surface without providing the optical reflecting portion for all of them, One or a plurality of sheets may be provided. In addition, the optical reflection part is formed by a through hole having a predetermined opening, a slit, and a notch. However, since these penetrate the side plate, dust or the like may enter from this part depending on the use environment. . In such a use environment, it is preferable to use a transparent substrate for the housing side plate and apply or print the reflective material on the substrate.

  Since the light source device 1 can emit light from the LED 2 in a substantially uniform manner not only from the surface of the optical reflector 4 but also from the side plate surface of the housing 3, not only the surface illumination device described later but also vending It can be used by being incorporated into a game machine or a large game machine.

  Next, with reference to FIG. 4, a surface illumination device according to Embodiment 2 of the present invention will be described. 4 is a schematic top view of the surface illumination device according to Embodiment 2 of the present invention, and FIG. 5 is a cross-sectional view of the surface illumination device of FIG. 4 taken along line VV. In FIG. 4, the diffuser plate of the surface illumination device is removed so that the inside can be seen.

  As shown in FIGS. 4 and 5, the surface illumination device 8 includes four light source devices 1, a housing case 9 that houses these light source devices, and an opening of the housing case to block the light emitted from each light source device. The light source device 1 is disposed in the housing case 9 with a predetermined gap (distance), and the opening of the housing case 9 is covered with the diffuser plate 10. It has a configuration.

  The housing case 9 has a case bottom plate 9a having a larger area than the total sum of the bottom areas of the individual light source devices 1, case side plates 9b to 9e erected from the periphery of the case bottom plate, and the side facing the case bottom plate. The inner wall surface is formed of a reflective surface. The case bottom plate 9 a is larger than the total area of the bottom plate areas of the four housings 3 constituting the light source device 1. Further, the length of one side of the case bottom plate 9a is longer than the total length L1 of the housing side plates in the longitudinal direction. Further, the height h3 of the case side plate is higher than the height h1 of the housing side plate, as shown in FIG. The height (distance) of the gap between the optical reflection plate 4 and the diffusion plate 10 of the light source device 1 is h2, and h3 = h1 + h2. The height h2 is described as a gap D3 between the diffusion plate and the optical reflection plate of the light source device in the claims.

  As shown in FIG. 4, the surface lighting device 8 has a predetermined gap (distance) G <b> 1 between the adjacent light source devices 1 in the housing case 9 and a gap (distance) G <b> 2 between the case side plates. The opening 9f is covered and fixed with the diffusion plate 10 and assembled. In the claims, G1 is described as a gap D2 between the light source devices, and G2 is described as a gap D1 through which the light source device emits illumination light between the inner wall surface of the housing case. By this assembly, a gap (distance) h <b> 2 is formed between the light emitting surface of each light source device 1 and the diffusion plate 10. The relationship between these distances G1, G2 and h2 is important for obtaining uniform illumination light from the outer surface of the diffusion plate 10. That is, when the distances G1 and G2 are increased, the distance between adjacent light source devices 1 and the case side plate of the housing case 9 are darkened, and when the height h2 is increased, a desired illuminance cannot be obtained.

These relationships are set as follows depending on the presence or absence of the optical reflecting portion 7 of the housing side plate. This was confirmed by experiments.
(A) When an optical reflection part is not provided on the housing side plate of the light source device The distance G1 between the adjacent light source devices is equal to or less than half of the maximum distance W between the opposing side plates of the light source device 1 (see FIG. 4), and G2 is G1. And h2 is set to be 1/2 or more of G1. If it is in these relations, between gaps will not become dark and desired illuminance can be obtained. If these relationships are not met, it is difficult to obtain uniform illumination light.

(B) When the optical reflecting portion is provided on the housing side plate of the light source device If the optical reflecting portion is provided on the housing side plate, the area of the light emitting surface can be increased and the device can be made shorter than the above (a). That is, each light source device 1 emits substantially uniform LED light from the respective housing side plates 4b to 4e via the optical reflecting portion 7, and the emitted light is between the gaps between adjacent devices and within the housing case 9. The light is reflected from the wall surface and emitted from the diffusion plate 10. For this reason, compared with the above (a), the gaps G1 and G2 can be enlarged. G1 is one half or more of the maximum inter-plate distance W (see FIG. 4) of the light source device 1, and G2 is one half or more of G1. And h2 can be reduced to half or less of G1. As a result, the area of the light emitting surface of the surface illumination device can be increased and the device height can be reduced.

  In the surface lighting device 8, the side plates 9b to 9e of the housing case 9 are erected vertically from the case bottom plate 9a. However, like the surface lighting device 8A (see FIG. 6), the surface lighting device 8 is predetermined from the periphery of the case bottom plate 9a to the outside. The angle may be inclined. The inclination angle is preferably more than 90 ° and within 150 ° with respect to the plane of the case bottom plate 9a. By this inclination, the opening and the diffusion plate 10A are enlarged, the light emitting area is enlarged, and the height h2 ′ (h2 ′ <h2) can be further reduced. Here, since h3 ′ = h1 + h2 ′, h3 ′ <h3 and the height of the case side plate is small, that is, a thinner surface illumination device can be obtained.

  In addition, although the side plate of the storage case has a flat plate shape in this embodiment, it may be curved to the inside of the case. At this time, if the inner wall of the housing case is a reflecting surface such as a mirror surface, light can be emitted more efficiently from the housing case opening. Further, the side plate can be formed into a corrugated shape or other shapes instead of a flat plate. In this way, by changing the shape of the side plate of the housing case, the irradiation range and the brightness uniformity in the irradiation range can be adjusted in accordance with the application of the surface illumination device.

  Moreover, although the surface illuminating devices 8 and 8A of the said embodiment are comprised with the four light source devices 1, the number can be changed according to a use. For example, a single light source device 1 may be housed in a single housing case 9B as in a surface illumination device 8B (FIG. 7A).

  In the surface illumination devices 8, 8A, 8B of the above embodiment, the light source device 1 has a substantially square shape, and the housing cases 9, 9A, 9B for housing these light source devices have a substantially square shape. Any shape, for example, as shown in FIG. 7B, these may be rectangular.

  A rectangular surface illumination device will be described with reference to FIGS. 7B and 8. 7B is a schematic top view of the surface illumination device, FIG. 8A is a cross-sectional view taken along line VIIIA-VIIIA in FIG. 7B, and FIGS. 8B and 8B are side views of the optical reflecting portion provided on the side plate. In FIG. 7B, the diffuser plate of the surface illumination device is removed so that the inside can be seen.

  The surface illumination device 8 </ b> C includes a rectangular light source device 1 </ b> A, a housing case 9 </ b> C that houses the light source device, and a diffusion plate 10 </ b> B (see FIG. 8A) that covers the opening of the housing case. The light source device 1A, the housing case 9C, and the diffuser plate 10B are different in shape, but the configuration is the same as that of the light source device 1, the housing case 9 and the diffuser plate 10 of the surface illumination device 8, and the description thereof Omitted.

  The light source device 1A has a pair of short opposing housing side plates 3b 'and 3d' and a pair of long opposing housing side plates 3c 'and 3e', and these housing side plates are provided with optical reflecting portions. . Since these housing side plates 3b ', 3c' and 3c ', 3e' have different approach distances from the LED 2, the long side housing side plates 3c ', 3e' have side central reflecting portions 7a 'and side portions. An optical reflecting portion 7A ′ composed of the outer reflecting portion 7b ′ is provided. Since the short housing side plates 3b 'and 3d' are separated from the LED 2, there is no need for processing such as the side central reflecting portion 7a 'and the side outer reflecting portion 7b', and the through holes having the same opening area are formed. The optical reflecting portion 7E is provided.

  With reference to FIG. 9, FIG. 10, the surface lighting apparatus which concerns on Embodiment 3 of this invention is demonstrated. 9 shows a light source device and a surface illumination device using the light source device according to Embodiment 3 of the present invention, FIG. 9A is a schematic top view, and FIG. 9B is a side view of the surface illumination device of FIG. 9A. 9C is a cross-sectional view taken along line IXC-IXC in FIG. 9A, FIG. 10 shows a modification of the surface illumination device in FIG. 9A, FIG. 10A is a top view, and FIG. 10B is a cross-sectional view taken along line XB-XB in FIG. is there. In FIGS. 9A and 10A, the diffuser plate of the surface illumination device is removed so that the inside can be seen.

  A part of the configuration of the light source devices 1 and 1A and the surface illumination devices 8, 8B, and 8C using these light source devices is changed depending on applications.

  As shown in FIG. 9A, a surface illumination device 8D according to Embodiment 3 of the present invention includes a light source device 1B, a storage case 9D that stores the light source device 1B, and a diffusion plate (not shown) that covers the opening of the storage case. It consists of and. In addition, this surface illuminating device cut | disconnects the surface illuminating device 8C of FIG. 7B with the IXA-IXA line | wire, and changed a one part structure.

  The light source device 1B has four housing side plates 3b1 to 3e1. Among these housing side plates 3b1 to 3e1, the housing side plates 3e1, 3b1, and 3d1 are formed with optical reflecting portions. Further, the side plate 3c1 is not provided with an optical reflecting portion, and is formed only of a plate body. The housing case 9D includes a case bottom plate 9a, case side plates 9b1 to 9e1 erected from the periphery of the case bottom plate, and an opening 9f provided on the side facing the case bottom plate, and an inner wall surface is formed of a reflective surface. Has been. One case side plate 9c1 is provided with a slit 9c1 ′ that allows light from the light source device 1B to pass therethrough. The slit 9c1 ′ has an opening area that is the same as or slightly longer than the long side plate of the light source device and has a predetermined width. Illumination light is also emitted from the slit 9c1 ′. The surface illumination device 8D is used by being incorporated in a game machine or the like.

  In the surface lighting device 8, the case side plates 9b1 to 9e1 of the housing case 9 are erected vertically from the case bottom plate 9a1, but the case side plate of the housing case 9E is similar to the surface lighting device 8E (see FIGS. 10A and 10B). 9b1 ′, 9d1 ′, and 9e1 ′ may be inclined by a predetermined angle from the periphery of the case bottom plate 9a1. It is preferable that the inclination angle exceeds 90 ° and within 150 ° with respect to the plane of the case bottom plate 9a1. By this inclination, the opening and the diffusion plate 10B are enlarged, the light emitting area is enlarged, and the case height h2 ′ (h2 ′ <h2) can be further shortened. Since the side plate 9c1 is not provided with a reflecting portion and is provided with a slit 9c1 ′, the side plate 9c1 is erected vertically from the bottom plate 9a1.

1, 1A, 1B Light source device 2 Point light source 3 Housing 3a Housing bottom plate 3b-3e Housing side plate 4 Optical reflecting plates 7, 7A ', 7A-7E Optical reflecting portions 7a, 7a1, 7a2, 7a3 Side central reflecting portions 7b, 7b1 7b2, 7b3 Side outward reflection part 8, 8A-8E Surface illumination device 9, 9A-9E Housing case 9a Case bottom plate 9b-3e Case side plate 10, 10A-10C Diffusion plate

Claims (8)

A highly directional point light source,
A housing bottom plate in which the point light source is disposed, a housing side plate erected at a predetermined height from the periphery of the housing bottom plate, and a housing in which an opening is provided on a side facing the housing bottom plate and an inner wall surface is formed of a reflective surface;
In a light source device comprising an optical reflector that covers the opening and emits light from the point light source as substantially uniform illumination light,
The housing side plate is at least a part of the housing side plate, and a side central reflecting portion having high reflectivity and low light transmittance in a side plate region closest to the point light source, and an outer side plate of the side central reflecting portion. A light source device according to claim 1, wherein a side outward reflecting portion is formed in the region where the reflectance decreases and the light transmittance increases as the distance from the side central reflecting portion increases.   In the housing, the housing bottom plate has a rectangular shape, and the side central reflecting portion and the side outward reflecting portion are formed on at least one housing side plate of the housing side plate erected from the periphery of the rectangular shape. The light source device according to claim 1, wherein:   The side central reflection part is formed by a groove or a fine hole obtained by half-cutting the housing side plate, and the side outer reflection part is formed by a through-hole penetrating the housing side plate and having a predetermined opening area. The light source device according to claim 1, wherein the light source device is a light source device.   The light source device according to claim 1, wherein the point light source is a light emitting diode or a laser diode. A light source device according to any one of claims 1 to 4, an accommodation case having an opening and a size capable of accommodating one or a plurality of the light source devices, and a diffusion plate covering the opening,
The housing case includes a case bottom plate having an area larger than the total number of bottom areas of the light source devices accommodated, a case side plate standing from the periphery of the case bottom plate and higher than a housing side plate of the light source device, and the case bottom plate A gap (D1) for allowing the light source device to emit illumination light between the inner wall surface and the inner wall surface is formed with a box having an opening on the side facing the inner wall and an inner wall surface formed of a reflective surface. A surface illumination device characterized by being arranged.   The surface lighting device according to claim 5, wherein the case side plate is inclined in a range of 90 ° to 150 ° outward from a flat surface of the case bottom plate.   A plurality of the light source devices are accommodated in the housing case, the adjacent light source devices are arranged with a predetermined gap (D2) between each other, and the diffuser plate is provided for each of the plurality of light source devices. The surface illumination device according to claim 5, wherein the surface illumination device is disposed with a predetermined gap (D3) from the optical reflection plate.   The gap (D2) is one half or more of the maximum distance (W) between the opposing plates of the light source device, the gap (D1) is one half or more of the gap (D2), and the gap (D3) is The surface illumination device according to claim 7, wherein the surface illumination device is equal to or less than half of the gap (D2).

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