JP2012230878A - Surface light emitting unit for led type lightning - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface light emitting unit for an LED type lighting capable of achieving energy saving.SOLUTION: In the surface light emitting unit for the LED type lighting, the surface light emitting unit is an assembled structure made by combining a light guide plate 1 with an inclined surface, a diffuser wherein crimping and frosting treatment is applied to one side or both sides with an inclined surface same as that of the light guide plate 1, or the light guide plate 1, the diffuser, and a white reflecting plate so as not to have gaps among them. LEDs 2 are arranged on an incident surface of the light guide plate 1, and accordingly, the whole surface of the light guide plate can effectively emit light by using the minimum LED light in order to achieve energy saving and power saving.

Description

  The present invention uses an LED, a light guide plate such as plastic or glass, or a diffuser plate or a reflector that is paired with a light guide plate, to apply a light refraction or reflection principle to make any surface uniform. The present invention relates to a light guide plate, a diffusion plate, and a reflection plate that are used to emit light to form an illumination unit.

Currently, in addition to conventional incandescent bulbs and fluorescent lamps, LEDs are used as light sources for lighting fixtures in general houses, factory establishments, automobiles, aircraft, and ships. Incandescent bulbs and fluorescent lamps have a long history and are widely used worldwide, and their manufacturing costs are currently kept low, but they consume relatively large amounts of power and have a short operating life.
The LED, which is a new light source, has a long life with reduced power consumption.

  An LED as a light source for illumination has low power consumption, and demand is increasing from the viewpoint of power saving, energy saving, and long life. However, the disadvantage of LEDs is that the light directivity angle is narrow, and when a wide area such as a space is illuminated uniformly, the interior lights of automobiles, turn signals, and emergency guide lights in aircraft need to be visible from a wide area. , They have unsuitable characteristics.

  Conventional incandescent bulbs and fluorescent lamp substitutes using LED light sources diffuse light in a wide variety of ways, but because light obstacles are arranged on the transmission path, the illumination efficiency is poor, It is not the brightness that LED originally has. This problem is compensated by an increase in the amount of electric power, and as a result, an increase in the amount of heat generated results in a cost for heat dissipation.

  When an LED is used as a light source for illumination, it is necessary to avoid the danger due to the limited field of view immediately after the direct vision with the naked eye because of its narrow directivity angle.

  In the present invention, the disadvantage of the LED as the light source of illumination is that the directivity of light is narrow and is unsuitable for a wide range of uniform light emitting illumination such as a space by the material and shape of the light guide plate and the arrangement of the LEDs. The challenge is to enable illumination with uniform light emission.

  In the present invention, by utilizing the characteristics of the light emission directivity angle of the LED, the material and shape of the light guide plate and the diffuser plate and the arrangement of the LED that enable efficient surface-emitting illumination with reduced unnecessary light emission are provided. Is an issue.

  Currently, in addition to conventional incandescent bulbs and fluorescent lamps, LEDs are employed as lighting fixture light sources. Incandescent bulbs and fluorescent lamps consume relatively large amounts of power and have a short operating life. However, when an LED, a new light source, is used as a light source for lighting, it consumes less power, saves energy, has a long life, The lighting unit has the feature of preventing global warming.

  When LED is used as a light source of illumination, the light directivity angle is narrow and it has the characteristics unsuitable for wide range illumination, but by adopting the light guide plate of the present invention, even LED light source has a wide range. The lighting unit can illuminate the space uniformly.

  The LED is characterized as a light source for illumination, and the directivity angle of light is narrow. In the present invention, LED light is uniformly emitted, and a diffusion plate made of ABS resin or styrene resin is used on the light emitting surface. Thus, it is possible to provide a safe lighting unit that can be visually recognized from a wide range of nearly 180 degrees without any glare as when the LED light source is directly viewed by diffusing light.

  In order to realize efficient reflection and total reflection of the LED light source, to suppress unnecessary light emission, and to make the surface light emission with fewer LEDs, the material of the light guide plate is a material excellent in light transmission, glass, methacrylic resin This can be solved by using polycarbonate resin.

この事から、空気の屈折率を１．０とし、メタクリル樹脂の屈折率を１．４９とした場合に、全反射する臨界角度が約４２度となり、ポリカーボネートやガラスでも、ほぼ同様の角度で全反射となる。そのことから、ＬＥＤの発光指向角度が３０度の場合では、導光板の反射面は光の入射面に対して２４．５度を基準とし前後５度以内に設定し、全反射の効果によりロスのない反射とする。In order to achieve illumination that is uniform over a wide area and has little light leakage loss with an LED light source, it is desired to emit light by providing an angle to the shape of the light guide plate at an angle that totally reflects incident light within the reflection critical angle. Focus the light on any surface. Total reflection is the smallest incident angle at which light enters from where the refractive index is large to small, and the critical angle θ _c is expressed as follows.

Therefore, when the refractive index of air is 1.0 and the refractive index of methacrylic resin is 1.49, the critical angle for total reflection is about 42 degrees, and polycarbonate and glass are all at the same angle. It becomes reflection. Therefore, when the light emission directivity angle of the LED is 30 degrees, the reflection surface of the light guide plate is set within 5 degrees before and after 24.5 degrees as a reference with respect to the light incident surface, and is lost due to the effect of total reflection. It is assumed that there is no reflection.

  The number of LEDs used for uniform illumination with fewer LED light sources can be adjusted according to the area of the light emitting surface and the required luminance, but the optimum reflection angle is 24.5 degrees or less. Even when the angle is 3 to 24.4 degrees, surface emission can be efficiently performed by installing a white reflector outside the surface facing the light emitting surface of the light guide plate.

  The number of LEDs used for uniform illumination with fewer LED light sources requires a quantity that substantially fills the surface to emit light at the emission angle and directivity angle, but the LED directivity angle is 30. If the surface to emit light is a circle of 360 degrees with respect to the light source, LEDs that emit light outward at a uniform angle with respect to 360 degrees are arranged.

  In order to achieve a wide range of uniform illumination with an LED light source, it is necessary to efficiently guide the LED light into the light guide plate. However, the shape of the light guide plate on the LED light incident surface is a flat surface without fogging. The right angle of the light emission directing center of the LED light with respect to the surface is ideally 90 degrees, and 85 to 95 degrees is maintained.

  In order to achieve uniform illumination over a wide area such as the entire space with an LED light source, the LED arrangement for efficiently guiding the LED light into the light guide plate is in contact with the incident surface of the light guide plate LED light, or as much as possible. The position is within 1 mm of the proximity.

The LED light source can be used as an energy-saving lighting unit without excessive power by suppressing unnecessary light emission by using efficient reflection and total reflection, and surface emitting with fewer LEDs. It becomes possible.
The present invention is a surface light-emitting unit for LED illumination having the above-described configuration.

  When the diffusion plate, which is paired with the light guide plate, is combined with the same angle and shape as the light guide plate, the surface emitting illumination can be made thinner than the plate type.

  By coloring the diffuser plate paired with the light guide plate, a light emission color different from the LED light can be obtained.

1 is an overall view of the present invention. It is the figure and LED light which were seen from the light emission surface side of this invention. It is the figure and LED light which were seen from the side surface (cross section) of this invention. It is a figure of the fundamental light emission principle of this invention. The figure seen from the side in the case of using the diffuser plate and reflector of the present invention The figure seen from the side in the case of utilizing the diffuser plate and reflector of the same shape as the light guide plate of the present invention It represents plate-like diffusion. The diffusion plate of the same shape as the light guide plate of the present invention is shown.

  As the shape of the light emitting unit of the present invention, the light guide plate 1 and the diffusion plates 6 and 8 for the square plate type and the circular round type are made of a transparent resin.

  The light guide plate 1 having a shape matching the shape of the light emitting unit of the present invention, or the light guide plate 1 and the diffusion plates 6 and 8, or the light guide plate 1, the diffusion plates 6 and 8, and the reflection plate 10 are used in combination.

  The form of the LED 2 used for the light source of the light emitting unit of the present invention uses one or a plurality of the same forms for the bullet type, chip type top emission, and chip type side emission.

  Regardless of the colors such as red, blue, yellow, green, amber, white, etc., the LED 2 used for the light source of the light emitting unit of the present invention can be used in the same color or in combination depending on the application.

  The output luminance of the LED used for the light source of the light emitting unit of the present invention is selected according to the size of the lighting unit and the required brightness, and is used with heat dissipation and waterproofing as necessary.

  The diffuser plate 6 used for the light source of the light emitting unit of the present invention and the diffuser plate 8 having the inclined surface of the same angle as the light guide plate 1 can be used according to the application.

FIG. 1 is an example of use of a light guide plate for LED type surface emitting illumination of the present invention. FIG. 2 shows the arrangement of the plastic or glass light guide plate 1 and the LED 2 and the direction in which light is applied from the light emitting surface side of the light guide plate 1, and FIG. 3 shows them from the side cross-sectional side of the light guide plate 1. The light of the LED 2 is applied toward the light plate 1 from the thicker side to the thinner side. FIG. 4 shows the surface that emits light as a result of reflection of light inside the light guide plate 1 and the reflection surface angle 5 of the light guide plate 1. FIG. 5 shows an arrangement of the plate-like diffusion plate 6 and the light guide plate 1. In addition, the light 7 that spreads the light from the light emitting surface 3 with the diffusion plate and the light emitting surface of the reflecting plate 10 that is used when the reflecting surface angle 5 of the light guide plate 1 is not an optimum angle are subjected to a grain finish. It represents. FIG. 6 shows a case where the shape of the light guide plate and the diffusion plate are both round and round.
FIG. 7 shows a plate-like or sheet-like diffuser plate 6 and a diffuser plate light-emitting surface 9 having a texture or matte finish. FIG. 8 is an overall view of the diffusion plate 8 having the same reflecting surface angle 5 as that of the light guide plate 1 and having an inclined surface of the same angle as that of the light guide plate, which is used for reducing the thickness.

1 Light guide plate 2 LED
DESCRIPTION OF SYMBOLS 3 Light emission surface 4 LED light emission direction, the light propagation direction from a light source 5 Reflection surface angle of a light-guide plate 6 Plate-shaped diffuser plate 7 Light which spreads with a diffuser plate 8 Diffuser plate with the inclined surface of the same angle as a light-guide plate 9 Diffuser-plate light emission Surface 10 reflector

Claims (4)

  In an illumination unit using an LED light source, an LED is installed so that light is emitted from a thicker one to a thinner one in a plate-shaped light guide plate made of transparent plastic or glass, and from there to the inside of the light guide plate. A surface-emitting unit for energy-saving LED-type lighting, characterized by efficiently reflecting incident light on the inclined surface of the light guide plate.   In a lighting unit using an LED light source, a donut-shaped light guide plate made of transparent plastic or glass with a thick inner circumference, a thin outer circumference, and a slanted thickness. A surface-emitting unit for energy-saving LED lighting, characterized in that an LED is installed so as to emit light, and light entering the light guide plate is efficiently reflected by an inclined surface.   In an illumination unit using an LED light source, it has a light guide plate with a slope made of transparent plastic or glass, and a diffuser plate with the same slope and finished with one or both surfaces with a matte finish. Combined, LED light is efficiently reflected inside the light guide plate, and the surface emission of energy-saving LED lighting, characterized by uniform light emission obtained by passing light derived from one surface of the light guide plate through the diffuser plate unit.   In a lighting unit using an LED light source, a light guide plate with a slope made of transparent plastic or glass, and a diffuser plate with the same slope and with one or both surfaces finished with a matt finish. A white reflector is provided on the surface opposite to the inclined surface of the light plate, and they are combined to efficiently reflect the LED light inside the light guide plate and allow the light derived from one surface of the light guide plate to pass through the diffuser plate. A surface-emitting unit for energy-saving LED lighting, characterized by uniform light emission obtained by

Images