JPS5819580Y2 - Menkougen Sochi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a light diffusing device that effectively utilizes the amount of light from a light source to obtain a uniform illuminance surface.

For example, in order to illuminate an elongated display board of a radio, stereo, etc. with uniform illuminance, conventional methods have been used to illuminate the display board from behind the display board, to irradiate it from the sides, and to combine these methods.

When illuminating from behind, 4 to 5 or more irradiation lamps are arranged along the length of the display board at a distance of at least a certain distance from the display board, and uneven illuminance is prevented. When printing scales, etc. on the display board, should the printing density be varied to prevent the uneven illuminance, or should a diffuser plate be installed between the light source and the display board, corresponding to the location where the irradiation lamp is installed? Alternatively, the display board itself was coated with diffusion coating, which had drawbacks such as poor light utilization efficiency, the need for a large number of light source lamps, increased power consumption, increased depth, and increased assembly man-hours.

Also, when illuminating from the sides of a display board, it is customary to install multiple light source lamps along the longitudinal direction above or below the display board at both ends. In addition to requiring a large number of similar lamps, there was an undeniable drawback that only the area near the light source lamp was brightly illuminated, resulting in uneven illuminance.

In order to solve the above-mentioned drawbacks and obtain a light diffusing device that can provide a bright uniform illuminance surface with one or two light source lamps and can be formed into an ultra-thin type, the applicant of the present invention first developed a suitable light scattering device on the back surface. Light diffusion that makes it possible to obtain a uniform illuminance distribution on the front side of the substrate by bringing a reflective plate into contact with or close to the back side of the processed transparent substrate and illuminating the side edge of the transparent substrate with a light source lamp. Application for equipment (Japanese Patent Application 1986-127)
99 Japanese Unexamined Patent Publication No. 51-88042), and also filed an application for an application of the invention to a display board with illumination device for televisions, radios, etc.
19919)).

However, there are limits to the shape and effective dimensions of the uniform illuminance surface obtained by the above-mentioned light diffusion device.1 For example, in the case of a long and narrow uniform illuminance surface, one lamp can be used to When projecting light (Fig. 1), if a 6.3 V, 0.3 A, 25 mm long fuse tube type tungsten bulb is used as the light source, the effective uniform illuminance is up to 25 mm wide x 150 mm long. In the case of a two-lamp type projecting light from both end faces in the longitudinal direction (Fig. 2), if two light source lamps similar to the above are used, the length is 25rnTrLX 250mm.
However, in this light diffusion device, the light source is placed close to the end surface of the measuring part of the board, so there is a loss of light quantity, and the uniform illuminance is The shape was suitable for square shapes, but not circular or other regular shapes.

In view of the above, the present invention has the advantages of the above-mentioned patent application and actual application, and furthermore, it is difficult to efficiently obtain uniform illuminance when irradiating from the side end face of the substrate other than the elongated and uniform illuminance surface. The present invention aims to provide a light diffusing device that can provide a uniform illuminance surface even in terms of shape.

The present invention will be explained below with reference to drawings showing embodiments thereof.

Figures 3 and 4 show elongated devices such as stereos or radios.
・This is an example of a light diffusion device for a display board.

Reference numeral 1 denotes a transparent substrate made of a material such as acrylic with good light transmittance, and a transparent substrate is inserted through both the front and back surfaces in order to set a light source lamp on a line 71 that divides the length l in the longitudinal direction of the transparent substrate into thirds. It has a hole 1h with a mirror-finished inner wall.

The hole 1h does not need to penetrate both the front and back surfaces, but may be provided on either the back surface or the front surface.

The substrate 1 has a shape in which both ears of an elongated rectangular parallelepiped near the hole 1h are cut in a straight line or a parabola.

This substrate 1 has a front surface 1a and end surfaces 1c, ld, l.
e, 1f are (・The irradiated material (display board) 4 is finished with a mirror finish, and when actually used for stereos, radios, etc., has a light transmission pattern of 1 letter, 5 figures, etc.) The front surface 1a is arranged to face the back side of the.

In this case, whether to attach it to the front surface Ia and the back surface of the irradiated material 4, to just make contact with it, or to place it a little apart is a manufacturing issue for the radio, etc., and each can be selected as necessary. good.

Further, on the back surface 1b of the substrate 1, a rough surface is formed by hairline grooves in a portion corresponding to the same shape area as the portion of the front surface 1a facing the irradiated material 4 (display board, etc.). The remaining portion including the setting position of the hole 1h is formed into a mirror surface.

Of course, this surface roughening may be applied to the entire back surface 1b without any problem.

Unless a particular display effect is desired, the material 4 to be irradiated should not be set in a position where it will not directly receive the light from the light source lamp 2 (this will cause uneven illuminance).

In addition, by applying aluminum vapor deposition treatment or pasting a reflective plate 3 such as aluminum foil, which has excellent light reflectivity, on the end faces 1c to 1f of the substrate 1, the light source becomes more light than when the reflective plate 3 is not provided. The amount of light from the lamp can be used efficiently for lighting.

Further, on the back surface of the substrate 1, a diffuser reflecting plate 5 that transmits and absorbs less light is arranged so as to face the roughened surface.

The integration of the diffused light reflector 5 and the substrate 1 is similar to the elimination of minute grooves if the substrate 1 and the diffused reflector 5 are bonded with adhesive, etc., and the effect of the present invention is reduced. This is done by bonding the diffuser reflector 5 and the reflector 3 together.

Thereby, the light scattering reflector 5 is able to scatter the light that has passed through the substrate and reflect the light back to the front surface of the substrate 1.

Note that the thickness and shape of the diffuser reflector 50 are similar to the roughened surface provided on the substrate 1 in this embodiment, and the thickness and shape of the diffuser reflector 50 are
has the same shape area as the part facing the irradiated material 4, but as long as the hole 1h is not covered, there is no hindrance to making it larger, and in that case,
It is also possible to attach the substrate 1 directly to the diffuser reflector plate 5 by any suitable well-known means.

Now, the combined effect of the substrate 1 roughened with hairline grooves and the light beam from the light source lamp in the present invention will be explained with reference to FIG. 5A.

Hairline processing is usually performed on molded products or aluminum materials, etc., for example, to give a high-class feel to the operation panel of high-end audio equipment, or surface polishing. It has fine scratches and scratches.

In actual processing, the surface is roughened using fine sandpaper or a special hairline polishing machine.

The hairline-processed rough surface has many mirror-finished areas, and the light from the light source lamp 2 can be sufficiently captured to pass forward as well as to pass through specular reflection. Appropriate diffused reflection occurs.

Also, among the light transmitted to the outside, there is a diffuser reflector plate 5 on the back side.
There are those that return to the substrate and proceed to the uniform illuminance side, those that are repeatedly refracted and reflected, or those that return to the end surface of the substrate.
The light is not transmitted to the outside by the reflecting plates 3 attached to c to 1f, but is repeatedly scattered and reflected within the substrate, and is directed toward the illuminance side.

When the surface is roughened by creating irregularities randomly (for example, using Sand Plus or 7JD) as shown in Figure 5B,
Although there is a lot of scattered reflection, the amount of light that travels forward relies on transmitted light, so the illuminance decreases as you move away from the light source lamp, resulting in uneven illumination and difficult to achieve uniform illumination.

Due to the combined effect of each luminous flux as described above, the light source lamp 2
It becomes possible to irradiate the light effectively and evenly on a surface with uniform illuminance, and the material 4 to be irradiated set on the surface is brightly and uniformly illuminated.

According to experiments, it was confirmed that when a single light source similar to the above was used, the illuminance was about the same as the previous example, and the uniform illuminance surface was more than twice that of the previous example with a width of 25 degrees, that is, more than 300 mm. .

In the above embodiment, one light source lamp is used, but if the material to be irradiated is longer, it is of course possible to use a plurality of lamps.

Also, if the width of the irradiated material is also long. It is also conceivable that the back surface side of the substrate 1 is cut in a straight line or a parabola along the cross-sectional direction using the boundary line between the end surface 1e and the front surface 1a as a base line.

The embodiment shown in Fig. 6 shows a case where a circular uniform illuminance surface is obtained for use, for example, on the dial of an Anacog watch. The front surface 1'a and measurement surface of a transparent substrate 1' having front and back surfaces are formed into a mirror surface, and a reflective plate such as aluminum foil is placed on the side surface, and the back surface is treated (roughened) in the same manner as in the above example. A diffuser reflector 5 is disposed at the mirror surface, and a light source lamp 2 is set in a mirror-finished hole 1'h, so that the circular portion of the front surface 1'a corresponding to the dial becomes a uniform illuminance surface.

The present invention is not limited to the embodiments described above;
It can be applied to surface light source devices that provide uniform illuminance surfaces of various shapes.

As mentioned above, the present invention has a simple structure and is suitable for mass production, and since most of the light intensity of one or more power lamps is efficiently used, the uniform illuminance obtained per power lamp is reduced. The area becomes larger.

By using a transparent substrate that matches the shape of the illumination surface, uniform illumination surfaces of various shapes can be obtained.

Furthermore, since the device can be made extremely thin, it is extremely useful as a compact, high-performance, energy-saving light diffusing device that does not take up much storage space.

[Brief explanation of the drawing]

Figures 1 and 2 are perspective views showing a conventional light diffusing device, Figure 3 is a perspective cross-sectional view of an embodiment of the present invention, Figure 4 is an exploded perspective view of the embodiment of the present invention, and Figure 5. A. B is a partial oblique sectional view showing a conventional roughened surface and a roughened surface used in the present invention, respectively. FIG. 6 is a perspective sectional view showing another embodiment of the present invention. 1.1'...Transparent substrate, 2...Light source lamp, 3...Reflector, 4...Irradiated material, 6...・Diffusion reflector.

Claims (1)

[Scope of utility model registration request] A transparent substrate with good light transmittance is provided with a uniform illuminance surface for irradiating the material to be irradiated and other surfaces on the front side, and a surface with at least the same illumination intensity as the illuminance surface is provided on the back surface of the area corresponding to the illuminance surface. A surface roughening treatment is performed using hairline-shaped grooves with directionality in a certain shape and area to provide light reflection and light transmission properties, and the humming 0 of the substrate corresponds to at least the illuminance surface. A diffuser reflection plate is provided opposite to the roughened surface portion, and further penetrates either the front surface of the substrate other than the uniform illuminance surface portion, the corresponding back surface, or both of them. hand,
A light diffusion device characterized by having a hole for installing a light source.