JPH04289822A - Lighting equipment - Google Patents

Abstract

PURPOSE:To obtain a thin lighting equipment excellent in flatness of brightness distribution with high light emitting efficiency by a thin light guide plate by forming a thin wire-shaped scattered pattern, formed on the light guide plate, of two kinds of a continued single thin wire and a discontinued broken line-shaped thin wire. CONSTITUTION:A light guide plate 2 is a lighting system, in which an acrylic plate is used to adjacently arrange a cold cathode tube as a bar-shaped light source 1 in a light introducing end surface 5 of the plate, to form a broken line-shaped diffused pattern 3 in an A part adjacent to the bar-shaped light source 1 and a thin wire-shaped diffused pattern 4 in a B part distant from the bar-shaped light source 1, on the light guide plate 2. When flat brightness is intended obtained as the lighting system by generally forming only the thin wire-shaped diffused pattern 4 in the light guide plate 2, the nearer is the bar-shaped light source 1 the smaller a thickness of a thin wire is decreased, and the more distant from the bar-shaped light source 1 the larger the thickness is increased, but when the thin wire-shaped diffused pattern is provided, by forming the broken line-shaped diffused pattern 3 in the A part near the bar-shaped light source 1 with a thin wire width 0.06mm or less to hold the thin wire width to 0.06mm or more, a lighting equipment of small unevenness of brightness is obtained by eliminating generation of collapse and blur of printed ink.

Description

Translated fromJapanese

【発明の詳細な説明】[Detailed description of the invention]

【０００１】0001

【産業上の利用分野】本発明は、主として液晶表示体等
のバックライト等に使用される薄型の面照明装置に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin surface illumination device used primarily as a backlight for liquid crystal displays and the like.

【０００２】0002

【従来の技術】従来、印刷により拡散パターンを形成す
るものとして特開昭６３−６２１０５号公報に記載され
ているように網点で拡散パターンを形成した方式のもの
、あるいは細線で形成した方式のものが知られていた。BACKGROUND OF THE INVENTION Conventionally, as a method of forming a diffusion pattern by printing, a method of forming a diffusion pattern with halftone dots or a method of forming a diffusion pattern with thin lines as described in Japanese Patent Laid-Open No. 63-62105 has been used. Things were known.

【０００３】しかしかかる従来の照明装置は、網点で拡
散パターンを形成したものでは発光効率が低く、印刷誤
差が細線方式に比べ大きいという問題点を有しており、
一方細線で拡散パターンを形成するものは細線の太さが
０．０６ｍｍ以下の部分で印刷誤差が極端に大きくなる
ため、微細な細線を必要とする薄型化した導光板の場合
に印刷誤差による輝度ムラあるいは輝度平坦度が悪化し
やすいという問題点を有していた。However, such conventional illumination devices in which a diffused pattern is formed using halftone dots have low luminous efficiency and printing errors are larger than those in the thin line method.
On the other hand, with thin lines that form a diffused pattern, printing errors become extremely large in areas where the thin lines are 0.06 mm or less in thickness. This has the problem that unevenness or brightness flatness tends to deteriorate.

【０００４】0004

【発明が解決しようとする課題】そこで、本発明は薄型
導光板で発光効率の高い、輝度分布の平坦性に優れた薄
型照明装置を提供することを目的とする。SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a thin lighting device that uses a thin light guide plate, has high luminous efficiency, and has an excellent flatness of luminance distribution.

【０００５】[0005]

【課題を解決するための手段】本発明の照明装置は、導
光板とその端面に隣接配置された棒状光源より構成され
る平面照明装置において、前記導光板の対向する光出光
面の少なくとも一面に印刷により細線状の散乱パターン
を形成し、棒状光源からの距離に応じて前記細線の太さ
を増減させる。このとき前記細線状散乱パターンを、連
続した１本の細線及び連続しない破線状の細線の２種類
で形成することにより、細線の最小太さが０．０６ｍｍ
以上とすることを特徴とする。Means for Solving the Problems The illumination device of the present invention is a flat illumination device comprising a light guide plate and a rod-shaped light source disposed adjacent to an end face of the light guide plate. A thin line-shaped scattering pattern is formed by printing, and the thickness of the thin line is increased or decreased depending on the distance from the rod-shaped light source. At this time, by forming the thin line scattering pattern with two types of continuous thin lines and discontinuous broken thin lines, the minimum thickness of the thin lines is 0.06 mm.
It is characterized by the above.

【０００６】[0006]

【実施例】本発明の１実施例を図１に示す。導光板２は
アクリル板を使用し、その光導入端面５に棒状光源１と
して冷陰極管を隣接配置した。導光板２には破線状拡散
パターン３及び細線状拡散パターン４を形成する。棒状
光源１に近いＡ部に破線状拡散パターン３を形成し棒状
光源３から離れたＢ部に細線状拡散パターン４を形成し
た。[Embodiment] An embodiment of the present invention is shown in FIG. An acrylic plate was used as the light guide plate 2, and a cold cathode tube as a rod-shaped light source 1 was arranged adjacent to the light introduction end face 5 of the light guide plate 2. A broken line diffusion pattern 3 and a thin line diffusion pattern 4 are formed on the light guide plate 2 . A broken line diffusion pattern 3 was formed in a section A near the rod-shaped light source 1, and a thin line-shaped diffusion pattern 4 was formed in a section B away from the rod-shaped light source 3.

【０００７】図５は図３に示すような細線状拡散パター
ン４のみによる導光板の細線の太さを現す。導光板２の
厚さ２ｍｍ、導光板の光入射面５から対向する面までの
長さ２００ｍｍ、細線状拡散パターンのピッチ１ｍｍで
のものである。一般に導光板２に細線状拡散パターン４
のみを形成し照明装置として平坦な輝度をえようとする
と棒状光源１に近づくほど細線の太さは減少し棒状光源
１から遠ざかるほど増加することがわかる。細線状拡散
パターンの太さは光導入端面５から約５０ｍｍまで０．
０６ｍｍ以下であり、実際にスクリーン印刷により製造
したところ、この部分で印刷されたインキのツブレ及び
カスレが発生し結果として輝度ムラが大きく満足な照明
装置が得られなかった。FIG. 5 shows the thickness of the thin line of the light guide plate formed only by the thin line-shaped diffusion pattern 4 as shown in FIG. The thickness of the light guide plate 2 is 2 mm, the length from the light incident surface 5 of the light guide plate to the opposing surface is 200 mm, and the pitch of the thin line diffusion pattern is 1 mm. Generally, a thin linear diffusion pattern 4 is formed on the light guide plate 2.
It can be seen that when attempting to obtain flat brightness as a lighting device by forming only a thin line, the thickness of the thin line decreases as it approaches the rod-shaped light source 1, and increases as it moves away from the rod-shaped light source 1. The thickness of the thin line diffusion pattern is 0.0 mm from the light introduction end face 5 to approximately 50 mm.
0.6 mm or less, and when it was actually manufactured by screen printing, the printed ink blurred and faded in this area, resulting in large brightness unevenness and a satisfactory lighting device could not be obtained.

【０００８】図４は図１に示すような、破線状拡散パタ
ーン３及びと細線状拡散パターン４を混在させたもので
各線の太さを示す。さらに、このときのＡ部の破線状拡
散パターン３の詳細図を図２に示す。Ａ部の破線状拡散
パターンを形成する各破線の長さは２．５ｍｍ、各破線
の間隔は１．５ｍｍである、このとき破線状拡散パター
ン及び細線状拡散パターン各部の最小線幅は０．０６ｍ
ｍ以上である。FIG. 4 shows a combination of a broken line diffusion pattern 3 and a thin line diffusion pattern 4 as shown in FIG. 1, and shows the thickness of each line. Furthermore, a detailed view of the broken line diffusion pattern 3 in the A section at this time is shown in FIG. The length of each broken line forming the broken line diffusion pattern in part A is 2.5 mm, and the interval between each broken line is 1.5 mm. At this time, the minimum line width of each part of the broken line diffusion pattern and the thin line diffusion pattern is 0.5 mm. 06m
m or more.

【０００９】このときの線幅は、Ｗ１＝Ｗ２×（Ｌ１＋Ｌ２）／Ｌ１Ｗ１：破線の太さＷ２：細線の設計状の太さＬ１：破線を形成する１つの線の長さＬ２：破線を形成する各線の間隔であらわされる。このときＬ２は１．５ｍｍに固定する
必要はなく、細線のピッチＰの１．５倍以下であれば良
好な結果が得られた、さらにＬ２・Ｌ１を連続的に可変
しても良い。また波線状拡散パターンは図２に示したよ
うにとなり合うパターンの間で波線の間隔Ｌ２がずれる
ように設計すると良好な結果が得られている。The line width at this time is W1=W2×(L1+L2)/L1 W1: Thickness of the broken line W2: Thickness of the thin line design L1: Length of one line forming the broken line L2: Thickness of the broken line It is expressed by the interval between each line formed. At this time, L2 does not need to be fixed at 1.5 mm, and good results have been obtained as long as it is 1.5 times or less the pitch P of the fine lines.Furthermore, L2 and L1 may be varied continuously. Further, good results have been obtained when the wavy line diffusion patterns are designed so that the spacing L2 between the wavy lines is shifted between adjacent patterns as shown in FIG.

【００１０】図６は、一般的なスクリーン印刷で細線を
形成したときの誤差を示す図で縦軸は細線幅に対する誤
差の割合を示している、細線幅が０．１ｍｍ以下で誤差
が増加し、特に０．０６ｍｍ以下では急激に増加する事
がわかる。FIG. 6 is a diagram showing the error when forming a thin line by general screen printing. The vertical axis shows the ratio of error to the width of the thin line. The error increases when the width of the thin line is 0.1 mm or less. , it can be seen that it increases rapidly especially when the thickness is 0.06 mm or less.

【００１１】従って、細線の線幅が０．０６ｍｍ、より
好ましくは０．１ｍｍ以下の部分を、破線状拡散パター
ンとし、その線幅が０．０６ｍｍ、より好ましくは０．
１ｍｍ以上とすればスクリーン印刷が高精度で製造でき
る、すなわち高輝度・輝度均一性に優れる照明装置の製
造が可能となる。[0011] Therefore, the portion where the line width of the thin line is 0.06 mm, more preferably 0.1 mm or less is made into a broken line diffusion pattern, and the line width is 0.06 mm, more preferably 0.1 mm or less.
If the thickness is 1 mm or more, screen printing can be performed with high precision, that is, a lighting device with high brightness and excellent brightness uniformity can be manufactured.

【００１２】0012

【発明の効果】本発明は、以上説明したように平面照明
装置の導光板上にスクリーン印刷により形成される拡散
パターンを基本的には細線で形成し、この細線の幅を棒
状光源からの距離に応じ増減させる、さらに細線幅が０
．０６ｍｍ以下となる部分では、破線状細線で置き換え
る事により最小線幅を０．０６ｍｍ以上とする事により
、スクリーン印刷の精度を向上させる事を可能とし、こ
のことによって照明装置の高輝度・輝度均一性をより向
上できるという効果を有する。さらに印刷精度の向上に
より製造に際しての不良発生を減少させることが可能で
あり、ひいては照明装置の価格の低減にも寄与するもの
である。Effects of the Invention As explained above, the present invention basically forms a diffusion pattern formed by screen printing on the light guide plate of a flat illumination device with thin lines, and the width of the thin lines is determined by the distance from the rod-shaped light source. The thin line width is increased or decreased according to
．． In areas where the width is less than 0.06 mm, the minimum line width is reduced to 0.06 mm or more by replacing it with a broken thin line, making it possible to improve the precision of screen printing.This allows for high brightness and uniform brightness of lighting equipment It has the effect of further improving sexual performance. Furthermore, the improvement in printing accuracy makes it possible to reduce the occurrence of defects during manufacturing, which in turn contributes to a reduction in the price of the lighting device.

【図面の簡単な説明】[Brief explanation of the drawing]

【図１】本発明の一実施例を示す正面図。FIG. 1 is a front view showing an embodiment of the present invention.

【図２】本発明の第１図破線状パターンの詳細を示す詳
細図FIG. 2 is a detailed view showing the details of the broken line pattern shown in FIG. 1 of the present invention.

【図３】従来の細線状拡散パターンによる導光板を示す
正面図。FIG. 3 is a front view showing a light guide plate with a conventional thin line diffusion pattern.

【図４】本発明による波線状拡散パターン及び細線状拡
散パターンの線の太さを現すグラフFIG. 4 is a graph showing the line thickness of the wavy line diffusion pattern and the thin line diffusion pattern according to the present invention.

【図５】従来の細線状拡散パターンによる線の太さを現
すグラフ[Figure 5] Graph showing the thickness of the line due to the conventional thin line diffusion pattern

【図６】スクリーン印刷による細線の誤差を現すグラフ
[Figure 6] Graph showing errors in thin lines due to screen printing

【符号の説明】[Explanation of symbols]

１　　　　　　棒状光源２　　　　　　導光板３　　　　　　破線状拡散パターン４　　　　　　細線状拡散パターン５　　　　　　光導入端面６　　　　　　透明シート７　　　　　　光導入端面８　　　　　　乱反射部1 Rod-shaped light source2 Light guide plate3. Broken line diffusion pattern4 Thin line diffusion pattern5 Light introduction end face6 Transparent sheet7 Light introduction end face8 Diffuse reflection part

Claims (1)

Translated fromJapanese

【特許請求の範囲】[Claims]【請求項１】導光板とその端面に隣接配置された棒状光
源より構成される平面照明装置において、前記導光板の
対向する光出光面の少なくとも一面に印刷により細線状
の散乱パターンを形成し、棒状光源からの距離に応じて
前記細線の太さを増減させる。このとき前記細線状散乱
パターンを、連続した１本の細線及び連続しない破線状
の細線の２種類で形成することにより細線の最小太さが
０．０６ｍｍ以上とすることを特徴とする照明装置。1. A flat illumination device comprising a light guide plate and a rod-shaped light source disposed adjacent to an end face thereof, wherein a thin line-shaped scattering pattern is formed by printing on at least one of the opposing light output surfaces of the light guide plate, The thickness of the thin line is increased or decreased depending on the distance from the rod-shaped light source. In this case, the lighting device is characterized in that the thin line scattering pattern is formed of two types: a continuous thin line and a discontinuous broken line, so that the minimum thickness of the thin line is 0.06 mm or more.