JPH0116242Y2

JPH0116242Y2 -

Info

Publication number: JPH0116242Y2
Application number: JP2142084U
Authority: JP
Priority date: 1984-02-17
Filing date: 1984-02-17
Publication date: 1989-05-15
Also published as: JPS60134202U

Description

【考案の詳細な説明】この考案は、車輌用灯具のインナーレンズに関
する。[Detailed Description of the Invention] This invention relates to an inner lens for a vehicle lamp.

従来、車輌用灯具のインナーレンズは、裏面に
フレネルカツトが施され、表面には魚眼カツトが
施されており、裏面のフレネルカツトの焦点位置
に光源があるため、光源から放射された光は光軸
に平行な光線となり、表面に施された魚眼カツト
により灯具の機能に合つた適当な拡散光となつて
外部に照射されていた。しかしながら、インナー
レンズに魚眼カツトを施すには、レンズの基本肉
厚がかなり厚くなければならず、魚眼カツトのピ
ツチが大きくなるとレンズの厚さも厚くなり、こ
のためレンズの重量が増大し、灯具の奥行寸法も
大になる。また、魚眼カツトの曲率半径は上下，
左右で異なる場合が多く、専用のカツターを必要
とし、その加工が厄介であり、かつカツトの磨き
加工も手間どる欠点がある。 Conventionally, the inner lens of a vehicle lamp has a Fresnel cut on the back side and a fisheye cut on the front side, and since the light source is at the focal point of the Fresnel cut on the back side, the light emitted from the light source is The light beam was parallel to the optical axis, and the fisheye cut on the surface turned it into an appropriately diffused light that matched the function of the lamp and was irradiated to the outside. However, in order to make a fisheye cut on the inner lens, the basic thickness of the lens must be quite thick, and as the pitch of the fisheye cut increases, the thickness of the lens also increases, which increases the weight of the lens. The depth dimension of the light fixture also increases. In addition, the radius of curvature of the fisheye cut is
The left and right sides are often different, and a special cutter is required, which is cumbersome to process, and polishing the cut is also time-consuming.

本考案は、上記従来の難点を除去するためにな
され、インナーレンズの薄肉化、軽量化を目的と
し、その構成は基本肉厚１mm以下のレンズ本体を
形成し、この表面にピツチが0.3mm以下の極小フ
レネルカツトを施した多角形部を縦横に隙間なく
多数配列し、裏面にはピツチが0.3mm以下の極小
フレネルカツトを全体に形成したことを要旨とす
るものである。 The present invention was made in order to eliminate the above-mentioned conventional difficulties, and aims to make the inner lens thinner and lighter. Its structure is to form a lens body with a basic wall thickness of 1 mm or less, and a pitch on this surface of 0.3 mm or less. The gist is that a large number of polygonal parts with extremely small Fresnel cuts are arranged vertically and horizontally without gaps, and on the back side, extremely small Fresnel cuts with a pitch of 0.3 mm or less are formed all over.

以下、図示の実施例により本考案を具体的に説
明すると、１は合成樹脂で基本肉厚が従来の魚眼
カツトを施したインナーレンズでは不可能であつ
た１mm以下のフイルム状に形成されたレンズ本体
であり、この表面には多角形（図例では長方形）
部１ａが隙間なく多数縦横に配設され、かつレン
ズカツトピツチ0.3mm以下の極小フレネルカツト
１ｂがそれぞれ多角形部１ａのセンターＣを中心
として形成されている。また、レンズ本体１の裏
面側には、レンズカツトピツチ0.3mm以下の極小
フレネルカツト１ｃがレンズ本体１のセンター
c′を中心として面全体に形成されている。 Hereinafter, the present invention will be specifically explained with reference to the illustrated embodiments. 1 is made of synthetic resin and is formed into a film shape with a basic thickness of 1 mm or less, which is impossible with a conventional inner lens with a fisheye cut. This is the lens body, and its surface has a polygonal shape (rectangular in the example).
A large number of portions 1a are arranged vertically and horizontally without gaps, and extremely small Fresnel cuts 1b with a lens cut pitch of 0.3 mm or less are each formed around the center C of the polygonal portion 1a. In addition, on the back side of the lens body 1, there is a very small Fresnel cut 1c with a lens cut pitch of 0.3 mm or less at the center of the lens body 1.
It is formed over the entire surface with c' as the center.

ところで、人間の視覚における解像力は個人差
は勿論あるものの、およそ視角にて40〜60″であ
り、フレネルカツトの輪状に発生する明暗（発光
光部と非発光部）を感じることの出来る距離ｄは
フレネルカツトのピツチをＰとすれば、ｄ＝Ｐ／tan40〜60″＝3438P〜5155P なる関係式が成り立つ。 By the way, the resolving power of human vision varies from person to person, but it is approximately 40 to 60'' in terms of visual angle, and the distance d at which you can feel the brightness and darkness (light-emitting and non-light-emitting areas) that occurs in the ring shape of a Fresnel cut. If the pitch of the Fresnel cut is P, then the following relational expression holds true: d=P/tan40~60''=3438P~5155P.

ランプの外観デザインを評価する距離は通常１
mm前後である。この距離からしてランプのレンズ
面上に生じる明暗の縞を目立たなくするために
は、前記の距離ｄを１mm以下にする必要があり、
前式より逆算するとフレネルカツトのピツチ１は
0.3mm以下にすれば良いことになり、実験におい
ても良好であるとの結論が得られた。 The distance to evaluate the external design of the lamp is usually 1
It is around mm. Considering this distance, in order to make the bright and dark stripes that occur on the lens surface of the lamp less noticeable, the distance d needs to be 1 mm or less,
Calculating backwards from the previous formula, the pitch of the Fresnel cut is 1.
It was concluded that it would be sufficient if the thickness was set to 0.3 mm or less, and the results were also concluded to be satisfactory in experiments.

本考案に係るインナーレンズは上記のように構
成され、第４図に示すように裏面を光源２側に向
け、カバー又はアウターレンズ３の内側にセツト
して使用される。そして、インナーレンズのフレ
ネルカツト１ｃの焦点距離に光源２があるため、
この光源から放射された光は前記インナーレンズ
のフレネルカツト１ｃにより光軸に平行な光線と
なり、かつ表面側のフレネルカツト１ｂにより集
光され、その後拡散されるように外部に照射され
る。即ち、前記平行光線は多角形部１ａ毎に集光
された後拡散されるので、全体として見れば適当
に拡散された状態になる。なお、この場合アウタ
ーレンズ３はレンズカツトが施されていない。 The inner lens according to the present invention is constructed as described above and is used by being set inside the cover or outer lens 3 with the back surface facing the light source 2 side as shown in FIG. Since the light source 2 is located at the focal length of the Fresnel cut 1c of the inner lens,
The light emitted from this light source becomes a beam parallel to the optical axis by the Fresnel cut 1c of the inner lens, is condensed by the Fresnel cut 1b on the front side, and is then irradiated to the outside so as to be diffused. That is, since the parallel light beams are focused on each polygonal portion 1a and then diffused, the light beams as a whole are appropriately diffused. Note that in this case, the outer lens 3 is not provided with a lens cut.

本考案によれば、インナーレンズをフイルム状
に形成すると共に、極小のフレネルカツトを設け
たので、インナーレンズの薄肉化、軽量化が可能
となり、かつ面倒な魚眼カツトの加工が不用とな
る。この結果、灯具の奥行寸法を小さく（薄型
化）することができ、インナーレンズが薄くフレ
キシブルであるからアウターレンズの曲面に沿わ
せて密着させることができ、さらにアウターレン
ズの魚眼カツトも不用となつて加工の手間が省け
る等のすぐれた効果を奏する。 According to the present invention, since the inner lens is formed into a film shape and a very small Fresnel cut is provided, the inner lens can be made thinner and lighter, and the troublesome processing of fisheye cuts is not required. As a result, the depth of the lamp can be reduced (thinner), and since the inner lens is thin and flexible, it can fit closely along the curved surface of the outer lens, and there is no need for a fisheye cut on the outer lens. It has excellent effects such as saving time and effort in processing.

[Brief explanation of drawings]

第１図は本考案に係るインナーレンズの一部を
示す正面図、第２図はその平面図、第３図は背面
図、第４図は使用状態を示す説明図である。１……レンズ本体、１ａ……多角形部、１ｂ…
…極小フレネルカツト、１ｃ……極小フレネルカ
ツト、２……光源、３……アウターレンズ。 FIG. 1 is a front view showing a part of the inner lens according to the present invention, FIG. 2 is a plan view thereof, FIG. 3 is a rear view, and FIG. 4 is an explanatory view showing the state of use. 1... Lens body, 1a... Polygonal part, 1b...
...Minimum Fresnel cut, 1c...Minimum Fresnel cut, 2...Light source, 3...Outer lens.

Claims

[Scope of utility model registration request]

A lens body with a basic wall thickness of 1 mm or less is formed, and a large number of polygonal parts with extremely small Fresnel cuts with a lens cut pitch of 0.3 mm or less are arranged vertically and horizontally without gaps on the front surface of this lens body, and the lens cut pitch is 0.3 mm or less on the back surface.
An inner lens for a vehicle lamp characterized by forming an extremely small Fresnel cut of mm or less over the entire surface.