JPH0317321B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The circular diffuser lens of the present invention will be explained according to the following items.

A. Industrial field of application B. Summary of the invention C. Prior art [Figures 7 and 8] D. Problems to be solved by the invention [Figures 7 and 8] E. Means for solving the problems F Embodiments [FIGS. 1 to 6] G. Effects of the invention (A. Field of industrial application) The present invention relates to a novel circular diffuser lens. Specifically, it is a circular diffuser lens that is provided with a substantially semi-cylindrical diffuser lens element extending radially, and is a novel circular diffuser lens that makes dark areas between adjacent diffuser lens elements in the circumferential direction inconspicuous. This is what we are trying to provide.

(B. Summary of the Invention) The circular diffusing lens of the present invention has a lens element forming surface divided into a plurality of annular regions arranged concentrically, and a substantially semi-cylindrical diffusing lens element extending in the radial direction in these annular regions. A large number of diffuser lens elements are formed, and the axes of the respective diffuser lens elements are shifted between adjacent annular regions.As a result, the dark area that occurs between adjacent diffuser lens elements in the circumferential direction is A straight line extending from the inner end to the outer end of the screen is arranged so that the dark part does not appear as a straight line, thereby making the dark part inconspicuous.

(C Prior Art) [Figures 7 and 8] In a lighting device such as an automobile signal light, when the lens surface is made to appear circular and uniformly illuminated from a relatively wide range, a diffuser lens element is formed on the lens. things will be done.

One such circular diffuser lens is one in which semi-cylindrical diffuser lens elements are formed radially.

FIGS. 7 and 8 show an example a of such a circular diffusing lens.

b is a hole formed in the center of lens a,
Therefore, the lens a has a substantially donut shape.

C, c, . . . are diffusion lens elements having a substantially semi-cylindrical shape, and are formed to extend radially from the inner end to the outer edge of the lens a.

Therefore, in such a circular diffuser lens a, the transmitted light is diffused in the circumferential direction by each of the diffuser lens elements c, c, .

(D Problem to be solved by the invention) [Figure 7,
[FIG. 8] However, the above-mentioned conventional circular diffuser lens a has a drawback in that the dark portions that occur between the circumferentially adjacent diffuser lens elements c, c, . . . are noticeable.

That is, in the case of this circular diffuser lens a, when the lights d, d, ... pass through the diffuser lens elements c, c, ..., they are once condensed and then diffused, so that Adjacent diffusing lens elements c, c,
The part that does not emit light between..., i.e., the non-light emitting part e,
e,... (with satin finish) is formed.
Moreover, in the case of the circular diffuser lens a in the above-mentioned state, the non-luminescent parts e, e,... appear as a single line extending radially from the inner end to the outer edge of the lens a, and the non-luminescent parts e, e,... There is a problem in that the parts are extremely conspicuous. Further, as shown in FIG. 7, the non-light-emitting portions e, e, . . . become wider toward the outer edge of the lens a and become more conspicuous. Furthermore, the non-light emitting part e,
If the curvature of the curved surface of the diffusing lens elements c, c, . . . is increased in order to improve visibility from a wider range, e, . . . will become even more conspicuous.

(E. Means for Solving Problems) In order to solve the above-mentioned problems, the circular diffuser lens of the present invention divides the lens element forming surface into a plurality of annular regions arranged concentrically, and these annular regions A large number of substantially semi-cylindrical diffusion lens elements extending radially are formed, and the axes of the lens elements formed in adjacent annular regions are shifted from each other.

Therefore, in the circular diffusing lens of the present invention, the boundaries between adjacent diffusing lens elements in the circumferential direction do not exist as lines extending in a straight line from the inner end to the outer edge of the lens, but are scattered over the entire lens surface. Therefore, the non-light-emitting portion formed at the boundary becomes less noticeable.

(Embodiment F) [Figs. 1 to 6] Details of the circular diffuser lens of the present invention will be described below with reference to illustrated embodiments.

1 in the figure is an automobile signal light using a circular diffuser lens according to the present invention.

Reference numeral 2 denotes a lamp body made of synthetic resin, which is approximately box-shaped with an open front. The front opening of the lamp body 2 is covered with a cover lens 3. The cover lens 3 is made of a material such as white or smoke color that cannot be seen inside when the light is not lit.

Reference numeral 4 denotes a reflecting mirror, which has a reflecting surface in the shape of a substantially paraboloid of revolution.

A light bulb 5 is attached to the reflecting mirror 4, and its filament 6 is placed approximately at the focal point of the reflecting mirror 4.

Reference numeral 7 denotes an inner lens disposed to cover the front surface of the reflecting mirror 4, and is made of transparent synthetic resin. The inner lens 7 has a substantially circular shape when viewed from the front, and has a central hole 8 formed in its center.

A large number of concentric protrusions 9, 9, . . . each having a triangular cross-sectional shape are formed on the front surface of the inner lens 7. Of the two surfaces 9a, 9a, ... and 9b, 9b, ... of these protrusions 9, 9, ..., the surfaces 9a, 9a, ... facing the center side are made to be reflective surfaces provided with a reflective film, The outward facing surfaces 9b, 9b, . . . are transparent surfaces.

On the rear surface of the inner lens 7, protruding condensing lens elements 10, 10 each having a semicircular cross-sectional shape are provided at locations corresponding to the protrusions 9, 9, . . . formed on the front surface.
...is being formed.

Reference numeral 11 denotes a retroreflective reflector attached to the center hole 8 of the inner lens 7.

Reference numeral 12 denotes a diffusion lens disposed close to the back side of the inner lens 7, which has a circular shape approximately the same size as the inner lens 7, and has a central hole formed in the inner lens 7 in its center. A center hole 13 of approximately the same size is formed.

The front surface of the diffusing lens 12 is divided into a plurality of annular regions 14, 14, . . . arranged concentrically,
These annular regions 14, 14, . . . have substantially semi-cylindrical diffusion lens elements 15, 15, .
is formed. The formation positions of the diffusion lens elements 15, 15, . . . formed therebetween are shifted by about half a pitch between adjacent annular regions 14. That is, the diffusion lens elements 15,1 formed in one annular region 14 adjacent to each other
Diffusion lens elements 15, 15, . . . whose axes 16, 16, . . . are formed in the other annular region 14
It is formed so as to correspond to the boundary parts 17, 17, .

In the automobile signal light 1 as described above, the light bulb 5
The light beams 18, 18, . Then, after passing through the diffusing lens 12, the light enters the inner lens 7 and heads toward the reflective surfaces 9a, 9a, . . . formed on the protrusions 9, 9, . . . on the front surface.

The light 18, 18, ... is reflected by the reflecting surface 9a,
It is reflected by the inner surface of 9a,... and the protrusions 9, 9,...
The protrusion 9, which passes through the transparent surfaces 9b, 9b, ...
The reflective surface 9 of the protrusion 9, 9,... one outside of 9,...
a, 9a, . . . are reflected by the outer surfaces of the reflecting surfaces 9a, 9a, .
During this period, the light beams 18, 18, . . . are directed in the circumferential direction by the diffusion lens elements 15, 15, . This gives it a tendency to spread in the radial direction.

In addition, for example, even if most of the strong external light 19 from a low position, such as sunlight at sunrise or sunset, is reflected by the reflective surface of the reflector 4 due to a slight deviation in the angle of incidence, the optical axis The light will not be parallel to x-x, and therefore false lighting will be prevented.

(G Effect of the Invention) As is clear from the above description, the circular diffuser lens of the present invention divides the lens element forming surface into a plurality of annular regions arranged concentrically, and extends radially into the annular regions. The present invention is characterized in that a large number of substantially semi-cylindrical diffuser lens elements are formed, and the axes of the diffuser lens elements formed in adjacent annular regions are shifted from each other.

Therefore, in the circular diffusing lens of the present invention, the boundaries between adjacent diffusing lens elements in the circumferential direction do not exist in a straight line from the inner end to the outer edge of the lens, but are scattered over the entire lens surface. Therefore, the non-light-emitting portion formed at the boundary becomes less noticeable.

In the above embodiment, the deviation of the center axes of the diffusing lens elements between adjacent annular regions was approximately half a pitch, but this deviation is not limited to approximately half a pitch; It is sufficient if the boundaries between adjacent diffusing lens elements are scattered over the entire lens surface so as not to be noticeable.

[Brief explanation of the drawing]

1 to 6 show an example of the implementation of the circular diffuser lens of the present invention, FIG. 1 is a partially cutaway front view of an automobile signal light using the circular diffuser lens of the present invention, and FIG. Fig. 3 is an enlarged sectional view taken along line - in Fig. 1, Fig. 4 is an enlarged sectional view taken along line - in Fig. 2, and Fig. 5 is a sectional view taken along line - in Fig. 2. 6 is an enlarged cross-sectional view of the main part of a circular diffuser lens, and FIGS. 7 and 8 show an example of a conventional circular diffuser lens. FIG. 7 is a front view, and FIG. FIG. 7 is an enlarged sectional view taken along the - line in FIG. 7; Explanation of symbols, 12...Circular diffuser lens, 14...
Annular region, 15... Diffusion lens element, 16...
Axial center.

Claims (1)

[Claims] 1. A lens element forming surface is divided into a plurality of annular regions arranged concentrically, a large number of substantially semi-cylindrical diffuser lens elements extending radially in the annular regions are formed, and adjacent annular regions are formed. A circular diffuser lens characterized in that the axes of the diffuser lens elements formed therein are shifted from each other between the regions.