JP2009087794A - Line lighting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize a line lighting device which uniformly emits light diffusely with a relatively simple structure. <P>SOLUTION: The lighting device (1) uses light-emitting diodes (2), and a plurality of light-emitting diodes (2) are arranged linearly and a translucent glass tube (7) with a frosting treatment is arranged at the upper part of the light-emitting diodes (2). Emitted light from the light-emitting diodes (2) enters from the lower part of the translucent glass tube of frosting treatment and passes inside the hollow tube and is emitted to the outside from the upper part. By the frosting treatment, transmittancy of light changes, and the luminance distribution of light emitted to the outside of the translucent glass tube is affected. In one desirable configuration, the frosting treatment should be processed so that the linear transmittancy at the cross-sectional center part of the translucent glass tube may be 5%-40%. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a lighting device using a light emitting diode, and more particularly to a novel line lighting device using a light emitting diode.

  The light quantity and luminous efficiency of light emitting diodes have been improved year by year, and they have come to be used as backlights for liquid crystal display devices and decorative lighting in stores. However, light emitting diodes have a strong light directivity, strong front light but weak side light, and still have a small range of use as an illumination light source, such as a small amount of light per element. On the other hand, Patent Document 1 discloses that a plurality of light emitting diodes are arranged in a line shape and covered with a kamaboko-shaped resin portion from above to form a line light source. Further, in Patent Document 2, a light-emitting diode is covered with a frosted glass envelope, and the strong front light of the light-emitting diode is diffused to increase light from the side surface to obtain a light distribution close to that of a general light bulb. Is disclosed.

JP 2002-299697 A JP 2007-220432 A

  In the case of Patent Document 1, the light from the light-emitting diodes arranged in a line can be seen through the kamaboko-shaped transparent resin portion, and even if the surface of the kamaboko-shaped resin portion is pear-treated. , There is a drawback in that the light transmittance is reduced and the total amount of light is reduced. In the case of Patent Document 2, a compact light bulb with good diffusion on the front and side surfaces can be obtained, but this does not suggest a configuration of a line-shaped light source.

  The present invention aims to solve the above-described problems, and achieves high luminance and good light diffusivity with a relatively simple structure in a structure in which light emitting diodes are used and arranged in a plurality of lines. There is.

  Another object of the present invention is not only a linear shape but also various shapes such as L-shape, U-shape, circle and square, white light, all colors of color, as well as ultraviolet and infrared radiation, intermittent lighting, light movement The present invention is to provide a line lighting device that can be easily applied to a wide range of uses such as general lighting, light sources for information equipment, and decorative light sources.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  The following is a brief description of an outline of typical inventions disclosed in the present application.

  That is, the illuminating device (1) according to the present invention uses a light emitting diode (2), a plurality of the light emitting diodes (2) are arranged in a line shape, and the light transmitting light is frosted on the light emitting diode (2). The structure which has arranged the property glass tube (7) is provided. The emitted light from the light emitting diode is incident from the lower part of the frosted translucent glass tube, passes through the hollow tube, and is emitted from the upper part to the outside of the tube. By the frost processing of the translucent glass tube, the light transmittance is changed, which affects the luminance distribution of the light emitted outside the translucent glass tube. In one desirable form of the present invention, the translucent glass tube is processed so that the linear transmittance at the center of the cross section is in the range of 5% to 40%. By this range of frost processing, almost uniform diffused light emission can be obtained outside the translucent glass tube.

  In the present invention, the plurality of light emitting diodes are fixed to the substrate, and a cover (6, 8, 9) is provided behind them to fix the substrate and the translucent glass tube. The cover has a reflection member on the inner surface thereof, and has a function of reflecting the light of the light emitting diode 2 together with the fixing function to effectively use the light.

  As a more specific form, if attention is paid to the free processability of the glass tube, the translucent glass tube can take various shapes such as a circular shape, an elliptical shape, and a flat shape. Further, the translucent glass tube may have various shapes such as a straight shape, an L shape, a U shape, a U shape, a circle shape, an ellipse shape, and a corrugated shape.

  The plurality of light emitting diodes can be made to emit light with a known control mode such as full lighting, blinking, or light movement based on an external signal.

  The effects obtained by the representative ones of the inventions disclosed in the present application will be briefly described as follows.

  That is, it is possible to realize a line illumination device that emits light evenly with a relatively simple configuration in which a frosted translucent glass tube is disposed on top of light emitting diodes arranged in a plurality of lines.

  FIG. 1 is a front sectional view along the axial direction of a line lighting device according to the present invention, FIG. 2 is a transverse sectional view perpendicular to the axial direction of the line lighting device according to the present invention, and FIG. 3 is a line lighting device according to the present invention. It is plane sectional drawing in alignment with the axial direction. That is, FIG. 1 shows a cross section taken along the line AA in FIG. 2, and FIG. 3 shows a cross section taken along the line BB in FIG.

  The line lighting device 1 includes a substrate 4 in which a plurality of light emitting diodes 2 are arranged on the front surface, for example, linearly, and a large number of protective resistors 3 are provided on the back surface, for example. In FIG. 1, only a part of a large number of protective resistors 3 is shown for convenience. Plated wiring is formed on the substrate 4, and driving signals and lighting control signals are supplied from the external lead wires 5 to the respective light emitting diodes via the plated wiring. The substrate 4 is accommodated inside a longitudinal cover 6 having a U-shaped cross section. A translucent glass tube 7 is disposed above the light emitting diode 2, and an outer circumferential arc surface of the translucent glass tube 7 is exposed from the longitudinal cover 6 along the axial direction thereof. End caps 8 and 9 made of, for example, heat-resistant rubber are fitted and fixed to both ends of the longitudinal cover 6, whereby the substrate 4, the longitudinal cover 6 and the translucent glass tube 7 are integrally supported. The longitudinal cover 6 and the end caps 8 and 9 constitute a cover and cover the light emitting diode, and the radiated light from the light emitting diode 2 is diffused and transmitted to the outside of the cover through the translucent glass 7 tube.

  The translucent glass tube 7 is frosted. In the frost processing, a glass surface is chemically corroded by using chemicals such as hydrofluoric acid and hydrochloric acid to create fine irregularities on the surface to form a ground glass. Further, as another method, it can be prepared by so-called sand blasting, in which sand or abrasive is sprayed on the glass surface to form ground glass.

  The inventors have conducted various frost processing tests on glass tubes with ammonium hydrogen fluoride aqueous solution, and the linear transmittance in the cross section of the glass tube changes depending on the degree of frost processing, thereby the light-emitting diode 2 placed under the glass tube. It has been found that it greatly affects the transmittance of light and the spread of light. That is, by controlling the linear transmittance in the cross section of the glass tube to a range of 5% to 40% by frosting, the loss of the light amount of the light emitting diode 2 is kept small, and the light in the glass tube axis and the radial direction is reduced. Since the diffusion is large, it is possible to realize an illumination device that looks as if it is a single line light source, even though the light emitting diodes 2 are arranged in a line.

  The frost processing is performed on the inner and outer surfaces of the translucent glass tube 7. The light emitted from the light emitting diode 2 is diffused and transmitted through the frosted surface (the frosted surface) of the translucent glass tube 2, and further diffused from the inner frosted surface and transmitted through the hollow portion of the glass tube. Then, the transmitted light is further diffused by the opposed inner frost surface, and finally, is diffused by the outer frost surface exposed from the cover and radiated to the outside. Since the inner and outer circumferences of the translucent glass tube 7 are frosted, the radiated light from the light emitting diode 2 diffuses and passes through the frost surface four times at the maximum. Moreover, since both the inner and outer circumferences of the translucent glass tube 7 are frosted, the light scattering in the axial direction, that is, the longitudinal direction of the glass tube 7 is compared in the thick portion of the translucent glass tube 7. Become bigger. Accordingly, the light-transmitting glass tube 7 is formed in a state where the light from the light-emitting diode 2 placed under the frosted light-transmitting glass tube 7 is reduced in loss and has a large diffusion in the tube axis and radial direction. Can be passed. That is, light incident on the translucent glass tube 7 from the lower surface spreads in the glass tube 7 with little loss and diffuses again on the inner and outer surfaces of the frosted surface of the upper surface of the glass 7. Can produce radiant light with extremely good diffusibility and low loss.

  As described above, frost processing is more effective when applied to both the inner and outer surfaces of the glass tube. Since the light spread on the outer frost surface on the lower surface of the glass tube further spreads on the frost surface on the inner surface thereof and is diffused again on the frost surface on the upper surface of the glass tube, a light source with extremely excellent light diffusion can be obtained. Although the frost processing may be performed only on the outer peripheral surface of the glass tube, in that case, in order to obtain the same transmittance as that in which the inner and outer peripheral surfaces are subjected to the frost processing, at least the frost processing time must be extended. Even in such a case, it is considered that the light diffusing performance is better when a translucent glass tube subjected to frost processing on both the inner and outer peripheral surfaces is used.

  The longitudinal cover 6 has light reflectivity on its inner surface. For example, white paint is applied to the inner surface, or the longitudinal cover 6 is formed of an aluminum material, and chrome plating is applied to the inner surface. Thereby, the effect | action which returns the light reflected from the translucent glass tube 7 or the leaked light in a pipe | tube again is realizable.

  A specific configuration example of the present invention will be described. The light-emitting diode 2 is a chip-type light-emitting diode capable of emitting three colors and having a directivity angle of 120 degrees, and this was fixed to a substrate 4 having a width of 8 mm and a length of 300 mm at a pitch of 5 mm. The longitudinal cover 6 is formed by machining an aluminum metal plate and mirror-finishing the inner surface. A translucent glass tube 7 is provided above the light emitting diode 2. The translucent glass tube 7 has an outer diameter of 8 mm, a length of 300 mm, frosted inner surface and outer surface, and its transmittance is 18%. The distance H from the top of the light emitting diode 2 to the top of the translucent glass tube 3 was set to 10.5 mm. A rated current of 20 mA was passed through the total number of light emitting diodes 2 arranged, and the luminance distribution at the top of the translucent glass tube 7 was measured. As a result, 85% uniformity was obtained over the entire length of the translucent glass tube 7. It can be seen as a single light source.

  Next, when a single color light emitting diode 2, for example, a green light emitting diode, is arranged in the same manner, a driving signal is sequentially input from the outside, and the light emitting diodes 2 are sequentially turned on, it can be seen that the green light emitting body moves. .

  Furthermore, if three-color light emitting diodes emitting red, green, and blue light are arranged, a light source whose emission color is changed by an external signal can be created.

  In the present invention, the translucent glass tube 7 is subjected to frost processing, and the transmittance is set in the range of 5% to 40%. If it is 5% or less, the luminance uniformity is improved, but the brightness is greatly attenuated. On the other hand, if the transmittance exceeds 40%, each light emission of the light emitting diode 2 is noticeable, and it becomes difficult to see the light source as a single light emission.

  In addition, the present invention makes maximum use of the free processability of glass. That is, in the present invention, the cross-sectional shape of the translucent glass tube 7 takes various shapes such as a circle, an ellipse, and a flat shape. By taking various cross-sectional shapes, it is possible to obtain a light source with good design and light emission efficiency. Furthermore, in the line illumination device according to the present invention, the translucent glass tube 7 is molded into various shapes such as a straight shape, an L shape, a U shape, a U shape, a circle shape, an ellipse shape, and a wave shape, and a light emitting diode is formed below the light emitting diode. Arranged to provide a single line illumination device having functions of all lights, movement, variable colors, etc. by the frost effect of the light-transmissive glass tube 7. In order to realize not only all lamps but also lighting or blinking functions such as moving or variable colors, the control signals may be input from the outside. In any case, a known technique can be applied to the drive control method.

  Although the invention made by the present inventor has been specifically described based on the embodiments, it is needless to say that the present invention is not limited thereto and can be variously modified without departing from the gist thereof.

  In the description of the present invention, the light emitting diode 2 is white, or a color light emitting diode such as red, green, and blue is used. However, the present invention is useful even when the light emitting diode 2 emits ultraviolet light or infrared light. That is, an ultraviolet light emitting diode or an infrared light emitting diode is arranged, and a translucent glass tube 3 having a frosted process is arranged on the upper part thereof, thereby making it possible to create a line light source with extremely good uniformity. It can be used as a light source. In the above embodiment, the light emitting diodes 2 are arranged on the substrate 4 at an interval of 5 mm, but it goes without saying that they may be arranged at other intervals. In addition, the rubber cap is used to integrally support the substrate, the translucent glass tube, and the cover, but the support structure is not limited thereto and can be changed as appropriate. It is also possible to adopt a small chip resistor as the protective resistor 3 and mount it on the surface of the substrate 4 together with the light emitting diode 2. It is also possible to adopt a structure in which the light emitting diode and the protective resistor are directly mounted on the bottom surface of the cover.

FIG. 1 is a front cross-sectional view along the axial direction of a line illumination device according to the present invention. FIG. 2 is a cross-sectional view orthogonal to the axial direction of the line illumination device according to the present invention. FIG. 3 is a plan sectional view along the axial direction of the line illumination device according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Line lighting device 2 Light emitting diode 3 Protection resistance 4 Board | substrate 5 External lead wire 6 Longitudinal cover 7 Translucent glass tube 8,9 End cap

Claims (7)

  A plurality of light emitting diodes arranged on one surface of a substrate having a predetermined length; a translucent glass tube disposed above the light emitting diodes along the arrangement of the light emitting diodes; and the translucent glass tube A line illumination device that includes a cover that covers the light emitting diode so that an outer peripheral arc surface of the glass tube is exposed along an axial direction thereof, and diffuses and transmits the light emitted from the light emitting diode through the glass tube.   2. The line illumination device according to claim 1, wherein a linear transmittance of light traversing the frosted translucent glass tube in the diameter direction is 5% to 40%.   The line illumination device according to claim 1, wherein the cover supports the substrate and the translucent glass tube and has a reflection member on an inner surface thereof.   The line illuminating device according to any one of claims 1 to 3, wherein the translucent glass tube is frosted on the entire outer peripheral surface and inner peripheral surface thereof.   The line illumination device according to any one of claims 1 to 4, wherein a cross section of the glass tube is circular, elliptical, or flat.   The line illuminating device according to claim 1, wherein the translucent glass tube has a linear shape, an L shape, a U shape, a U shape, a circular shape, an oval shape, or a corrugated shape. A translucent glass tube that has been subjected to frosting, a casing that covers the outer peripheral arc surface of the translucent glass tube so as to be exposed along the axial direction, and the translucent glass tube inside the casing. A plurality of light emitting diodes arranged along the axial direction below,
The translucent glass tube is subjected to frost processing on the entire outer peripheral surface and inner peripheral surface, and the linear transmittance of light traversing in the diameter direction is 5% to 40%,
The casing has a reflecting member on an inner surface thereof, the line lighting device.

Images