JPH0411285Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to a lighting device suitable for application to automobile sign lights, etc. This invention relates to an illumination device that exhibits a so-called gradation effect, in which brightness gradually changes as the distance from the center of the lens increases.

[Conventional technology]

The front lens is formed into an approximately semi-cylindrical shape (semi-cylindrical shape), and when viewed from the front, the top surface has the highest transmittance, and the transmittance decreases toward both ends in the circumferential direction, creating a gradation effect. In such a lighting device, the light that passes through the front lens appears to travel in a straight line in the lateral direction.

6 to 8 show an example of such a conventional lighting device, in which 1 is the lighting device, 2 is the lamp body, 3 is the light source, and 4 and 5 are the front surfaces that close the front opening of the lamp body 2. lens and inner lens.
The front lens 4 is formed into a substantially semi-cylindrical shape, and in order to produce a gradation effect, the lens surface is divided into multiple parts in the circumferential direction as shown in FIG. Transmissive paint is applied in layers with varying thicknesses. For example, the A part (top surface) located on the optical axis L of the front lens 4.
The area is unpainted, the area B is painted with 10% damping, the area C is painted with 20% damping, the area D is painted with 35% damping, and the area E is painted with 60% damping. Therefore, when viewing the lighting device 1 from the front, the A section is the brightest, and the B section is the brightest.
The brightness decreases as you go from Ha → Ni → Ho.
The light appears to run linearly in the longitudinal direction (axial direction) of the front lens 4.

A portion of the light emitted from the light source 3 is reflected by the multiple paraboloids 7 of the lamp body 2 to become parallel rays parallel to the optical axis, which are diffused by the diffusing lens 5 and then reflected by the front lens 4. irradiate. Further, the illumination color is changed by covering the light source 3 with a color filter (not shown) or by coloring the front lens 4 or the inner lens 5.

[Problem that the invention attempts to solve]

However, in such a conventional illumination device 1, the transmittance of the front lens 4 cannot be changed steplessly and continuously, and it is necessary to prepare many types of paint 6, which is expensive. It is quite expensive, and on top of that, each of the paints 6, B, D, C,
Since the hole part was cut off flat on a curved surface, the parting line could not be made neatly, resulting in many problems such as a decrease in product value.

[Means for solving problems]

The lighting device according to the present invention has been made to solve the above-mentioned problems all at once. A flexible louver sheet is arranged along the front or back surface of the louver sheet. A louver sheet is attached to the front lens so that the belt-shaped body is parallel to the axis of the front lens, and the extended surface of each belt-shaped body intersects with the axis.

[Effect]

In the present invention, the amount of light transmitted is controlled by a louver sheet made of a plurality of thin strips instead of paint, so the brightness in the circumferential direction of the front lens can be changed continuously.

〔Example〕

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

FIG. 1 is a sectional view showing an embodiment of the lighting device according to the present invention, and FIG. 2 is an exploded perspective view of a louver sheet.

Components that are the same as those in FIGS. 6 to 8 are designated by the same reference numerals, and their explanations will be omitted. The inner surface of the lamp body 2 that houses the light source 3 constitutes a paraboloid of revolution reflection surface 10, and the light that hits this reflection surface 10 and is reflected becomes a parallel ray parallel to the optical axis L and is directed forward, and the front lens 4 irradiate. The front lens 4 is formed into a substantially semi-cylindrical shape that is elongated in the left-right direction and is attached to the front opening of the lamp body 2, and has a louver sheet 12 on its surface that changes the amount of light transmitted in the line-of-sight direction A. is pasted over the entire surface.

As shown in FIG. 2, the louver sheet 12 has a large number of fine and opaque silicone rubber strips 14 arranged in parallel at regular intervals in the vertical direction inside a transparent silicone rubber sheet 13. The front and back sides of these strips 14 are integrated with a polycarbonate film 15 to form a sheet with a blind structure. When such a louver sheet 12 is attached to the surface of the front lens 4, the sheet 12 is curved along the surface of the front lens 4, and each strip is perpendicular to the surface of the front lens 4. When viewed from the front of the device, the apparent distance between adjacent strips 14 changes. That is, as shown in FIG. 3, when viewed from the front (in the direction of arrow A), the two strips 14a and 14b that face each other vertically across the optical axis L of the front lens 4 are approximately parallel to the optical axis L. , the distance d ₁ is the maximum, and as the distance from the optical axis L increases, the strips 14c, 14
The inclination angle of d... gradually increases, so when viewed from the direction of arrow A, the strips 14b, 14c, 14c
The intervals d ₂ , d _{3 . .} . between and 14d . . . also gradually become narrower.

In other words, the amount of light transmitted in the direction of the line of sight (direction A) is maximum at the center of the front lens 4, that is, the top surface, and the amount of light transmitted gradually decreases as it shifts in the vertical direction, creating a gradation effect. It is. Furthermore, when viewed from the front, the light passing through the louver sheet 12 is partitioned by the band-shaped body 14, so that it appears to run in a straight line in the lateral direction.

In this case, the center of curvature of the louver sheet 12 coincides with the center 0 of the front lens 4, and each strip 14a,
Since the extended surfaces of 14b, 14c, . . . pass through the center 0, the transmittance changes steplessly in the circumferential direction of the front lens 4. In addition, in the conventional device shown in Figures 6 to 8, the transmittance of parts A, B, C, D, and E is fixed regardless of the line of sight direction, so when viewed from the front, the central top surface (A part) is the brightest, and it gets darker as you go from B → H → D → H part,
If the viewing direction is moved in the circumferential direction of the front lens, the above-mentioned brightness relationship no longer holds true, but in the present invention, the apparent distance between the strips d ₁ , d ₂ , d simply increases as the distance from the viewing direction increases. _3. Since only the... changes, you can always get the same gradation effect even if you change the line of sight.

FIG. 4 is a sectional view showing another embodiment of the present invention. In this embodiment, the front lens 4 and the louver sheet 12 are integrally formed, and the sheet 12 is installed inside the front lens 4. The strip 14 of the louver sheet 12 is semitransparent and has a certain degree of transmittance. This has the advantage that even if the curvature of the front lens 4 is small, a beautiful gradation effect can be produced. On the other hand, if the strip 14 is opaque and constitutes a complete light-shielding wall as in the embodiment shown in FIG. In this case, it is necessary to increase the curvature of the front lens 4.

It is also possible to change the transmittance of the strip 14 from the central top surface of the front lens 4 toward both ends in the circumferential direction. The other configurations are the same as those of the above embodiment.

FIG. 5 is a sectional view showing another embodiment of the present invention. In this embodiment, the light from the light source 3 is transferred to the light guide plate 20.
The incident light 22 enters the light guide plate 20 through a light entrance part 21 provided on one side, and is reflected by a large number of stipples 2 made up of small V-shaped recesses provided on the lower surface of the light guide plate 20.
4 to the front surface side, and then the light guide plate 20
The light emitted from the surface of the front lens 4 is diffused by a diffusion plate 25 to illuminate the front lens 4. The lamp body 2 is formed into a shallow box shape, and the bottom surface thereof is inclined. The light guide plate 20 is formed into a wedge shape to reduce loss of light. The structure of the front lens 4 and the louver sheet 12 is the same as that of the embodiment shown in FIG.

In such a configuration, the device itself can be made thinner.

In addition, in all of the above examples, the louver sheet 1
Although the second band 14 is made colorless, it is of course possible to color it with an appropriate color, for example, red, and by doing so, a gradation effect of color change can be obtained at the same time.

[Effect of idea]

As described above, in the lighting device according to the present invention, the front lens is formed into a substantially semi-cylindrical shape, and a louver sheet consisting of multiple strips arranged in parallel at regular intervals is attached to the front lens along the curvature of the front lens. With this arrangement, the structure can be simplified and the brightness or illumination color can be continuously changed from the center of the front lens toward both ends in the circumferential direction with respect to the viewing direction. In addition, each strip is arranged parallel to the surface of the louver sheet so as to be perpendicular to it, and the angle changes by bending the louver sheet.
It is easy to manufacture the louver sheet.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing one embodiment of the present invention;
The figure is a perspective view of the louver sheet, Figure 3 is a diagram showing the spacing between the strips, Figure 4 is a sectional view showing another embodiment of the present invention, and Figure 5 is a diagram showing still another embodiment of the present invention. 6 to 8 are a perspective view, a sectional view, and an enlarged sectional view of a front lens of a conventional illumination device. 2... Lamp body, 3... Light source, 4... Front lens, 12... Louver sheet, 14... Band-shaped body,
20...Light guide plate.

Claims (1)

[Scope of utility model registration request] The louver comprises a substantially semi-cylindrical front lens provided in the front opening of the lamp body that houses the light source, and a flexible louver sheet disposed along the front surface or back surface of the front lens. The sheet is composed of a number of thin strips that are arranged parallel to each other at regular intervals so as to be perpendicular to the surface of the louver sheet, and the strips are aligned parallel to the axis of the front lens by attaching the louver sheet to the front lens. A lighting device characterized in that the extension surface of each strip-like body intersects the axis.