JP2007272209A - Light diffusion sheet for transmission type screen, and a method for manufacturing light diffusion sheet - Google Patents

Light diffusion sheet for transmission type screen, and a method for manufacturing light diffusion sheet Download PDF

Info

Publication number
JP2007272209A
JP2007272209A JP2007053803A JP2007053803A JP2007272209A JP 2007272209 A JP2007272209 A JP 2007272209A JP 2007053803 A JP2007053803 A JP 2007053803A JP 2007053803 A JP2007053803 A JP 2007053803A JP 2007272209 A JP2007272209 A JP 2007272209A
Authority
JP
Japan
Prior art keywords
light
refractive index
resin layer
lens
shielding body
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP2007053803A
Other languages
Japanese (ja)
Inventor
Koji Sone
浩二 曽根
Kenichi Honda
健一 本多
Masatomo Matsui
昌朋 松井
Yoshinobu Okada
好信 岡田
Tadashi Nakai
正 中井
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Holdings Corp
Original Assignee
Matsushita Electric Industrial Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Priority to JP2007053803A priority Critical patent/JP2007272209A/en
Publication of JP2007272209A publication Critical patent/JP2007272209A/en
Pending legal-status Critical Current

Links

Images

Landscapes

  • Overhead Projectors And Projection Screens (AREA)
  • Optical Elements Other Than Lenses (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light diffusion sheet which is for a transmission type screen, and which has excellent diffusion performance in such a way that an observer does not feel abnormal even when an image is observed while varying a viewing angle. <P>SOLUTION: The light diffusion sheet is equipped with: a light emitting side substrate 2 being a transparent substrate; light shielding bodies 3 with triangular shapes in cross sections arranged on one face of the light emitting side substrate 2 with an opening portion to be a light transmitting portion interposed in between; reflection lenses 7 disposed on slopes of the light shielding bodies 3 with triangular shapes in cross sections and formed with transparent resin layers with a first refractive index; a spherical refracting lens 8 formed on the opening portion 6 between adjacent light shielding bodies 3, formed with the transparent resin layer having the first refractive index; and a light incident side resin layer 5 covering the reflection lenses 7 and the spherical refracting lens 8, and formed with a transparent resin layer having a second refractive index which is higher than the first refractive index. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

本発明は、透過型スクリーン用の光拡散シートに係り、特に背面投射型ディスプレイに好適に利用できるものである。   The present invention relates to a light diffusing sheet for a transmissive screen, and can be suitably used particularly for a rear projection display.

近年大画面ディスプレイへの需要が高まっており、この中でも手軽に大画面表示が可能な背面投射型ディスプレイが期待されている。   In recent years, the demand for large-screen displays has increased, and among them, a rear projection display capable of easily displaying a large screen is expected.

図9は背面投射型ディスプレイ10を模式的に示す構造図である。図9において光学エンジン11の内部には光源となるランプ、照明光学系、色分解光学系、液晶パネル、色合成光学系などが適切に配置されている。ランプからの光は照明光学系を経て液晶パネルを照明する。照明光は液晶パネルによって空間変調され画像を形成する。その画像は投射レンズ12によって拡大投射される。   FIG. 9 is a structural diagram schematically showing the rear projection display 10. In FIG. 9, a lamp serving as a light source, an illumination optical system, a color separation optical system, a liquid crystal panel, a color synthesis optical system, and the like are appropriately arranged inside the optical engine 11. Light from the lamp illuminates the liquid crystal panel through the illumination optical system. The illumination light is spatially modulated by the liquid crystal panel to form an image. The image is enlarged and projected by the projection lens 12.

ミラー13によって折り曲げられ投射される画像光14は透過型スクリーン15上で結像する。画像光14は透過型スクリーン15を通過する際に拡散されるので、様々な角度からカラー画像を観察できる。これらの要素はキャビネット16の内部に配置され、装置内への外光の侵入を防止している。   The image light 14 bent and projected by the mirror 13 forms an image on the transmission screen 15. Since the image light 14 is diffused when passing through the transmissive screen 15, a color image can be observed from various angles. These elements are disposed inside the cabinet 16 and prevent the entry of external light into the apparatus.

図10は透過型スクリーン15の基本構成を示す模式図である。透過型スクリーン15は、フレネルレンズシート17と、光拡散シート1により構成されている。フレネルレンズシート17を投射側に、光拡散シート1を観察者側に向けて配置される。フレネルレンズシート17は、画像光出射面側に同心円状に形成された断面鋸歯状のフレネルレンズを備えている。   FIG. 10 is a schematic diagram showing the basic configuration of the transmission screen 15. The transmission screen 15 includes a Fresnel lens sheet 17 and a light diffusion sheet 1. The Fresnel lens sheet 17 is arranged on the projection side and the light diffusion sheet 1 is arranged on the observer side. The Fresnel lens sheet 17 includes a fresnel lens having a sawtooth cross section formed concentrically on the image light exit surface side.

光拡散シート1は、画像光入射面側から順に光拡散レンズと、光拡散レンズの集光部に光を透過する開口部を有する遮光体とで構成されている。一般に、光拡散レンズと遮光体は、透過型スクリーン15の水平方向にストライプ状に配列されている。   The light diffusing sheet 1 is composed of a light diffusing lens and a light shielding body having an opening that transmits light to the light condensing portion of the light diffusing lens in order from the image light incident surface side. In general, the light diffusing lens and the light blocking body are arranged in a stripe shape in the horizontal direction of the transmissive screen 15.

透過型スクリーン15に投射された画像光14は、フレネルレンズシート17で屈折され、光拡散シート1に対して垂直方向に投射する平行光9に調整される。
平行光9は、光拡散レンズによって集光され遮光体の開口部を通過した後に透過型スクリーン15の左右方向に拡散されて、背面投射型ディスプレイ10の左右方向に広い視野角で画像を観察することができる。
The image light 14 projected on the transmission screen 15 is refracted by the Fresnel lens sheet 17 and adjusted to parallel light 9 projected in the vertical direction with respect to the light diffusion sheet 1.
The parallel light 9 is collected by the light diffusion lens, passes through the opening of the light blocking body, and then is diffused in the left-right direction of the transmissive screen 15 to observe an image with a wide viewing angle in the left-right direction of the rear projection display 10. be able to.

一方、光拡散シート1の画像光出射面より入射する外光は、遮光体により吸収されるため、明るい部屋においても高コントラストで画像を観察することができる。このような光拡散シート1として、高屈折率透明樹脂と遮光体との境界面の全反射を利用した光拡散シート1が提案されている。この基本構造の立体図を図11に、断面図を図12に示す。この光拡散シート1は、高屈折率透明樹脂層18と、高屈折率透明樹脂層の一方の面に互いに平行に複数配置された三角形状の低屈折率材料で形成された遮光体3とを備えた構成としてある(例えば、特許文献1参照)。   On the other hand, since the external light incident from the image light exit surface of the light diffusion sheet 1 is absorbed by the light shielding body, an image can be observed with high contrast even in a bright room. As such a light diffusing sheet 1, a light diffusing sheet 1 utilizing total reflection at a boundary surface between a high refractive index transparent resin and a light shielding body has been proposed. A three-dimensional view of this basic structure is shown in FIG. 11, and a cross-sectional view is shown in FIG. The light diffusing sheet 1 includes a high refractive index transparent resin layer 18 and a light shielding body 3 formed of a triangular low refractive index material arranged in parallel with one another on one surface of the high refractive index transparent resin layer. It is the structure provided (for example, refer patent document 1).

この光拡散シート1は、高屈折率透明樹脂材料に入光する平行光9の一部を遮光体3の傾斜面上に露出した低屈折率材料の界面が反射レンズとなって、この反射レンズの長手方向に対して、直角となる方向へ拡散光として出光し、左右方向に広い視野角で画像を観察することができる。   In this light diffusion sheet 1, the interface of the low refractive index material in which a part of the parallel light 9 entering the high refractive index transparent resin material is exposed on the inclined surface of the light shielding body 3 serves as a reflection lens. The light can be emitted as diffused light in a direction perpendicular to the longitudinal direction, and an image can be observed with a wide viewing angle in the left-right direction.

しかしながら、この方式では、高屈折率透明樹脂の平坦面に垂直に入射する平行光9の一部が遮光体3の開口部6に入射され、拡散することなく通過する。一方、平行光9の残り部は、遮光体3の傾斜面の反射レンズ面で反射し、遮光体3の開口部6から反射レンズの傾斜角度に対応して方向を変えた平行反射光が透過し出射される。   However, in this method, a part of the parallel light 9 incident perpendicularly to the flat surface of the high refractive index transparent resin is incident on the opening 6 of the light shield 3 and passes without being diffused. On the other hand, the remaining part of the parallel light 9 is reflected by the reflecting lens surface of the inclined surface of the light shielding body 3, and parallel reflected light whose direction is changed from the opening 6 of the light shielding body 3 according to the inclination angle of the reflecting lens is transmitted. Then emitted.

このため、透過型スクリーン15の視野角は、図13に示すように、遮光体3の開口部6に平行光が直接入射して通過した視野角0°の出射光gcと、遮光体3の傾斜面で全反射した特定視野角の出射光gs,gs‘との3つの強いピークを有する視野角特性が現れる。   For this reason, the viewing angle of the transmissive screen 15 is such that the output light gc having a viewing angle of 0 ° through which parallel light directly enters and passes through the opening 6 of the light shielding body 3 and the light shielding body 3 as shown in FIG. A viewing angle characteristic having three strong peaks with the output lights gs and gs ′ having a specific viewing angle totally reflected by the inclined surface appears.

このような視野角特性を有する透過型スクリーン15に投影された画像をあらゆる角度から見た場合、観察角度によって明暗部分が出来てしまうという問題点があった。   When an image projected on the transmission screen 15 having such viewing angle characteristics is viewed from all angles, there is a problem that a bright and dark portion is formed depending on the observation angle.

このような、3つの輝度ピークを有する視野角特性を持つ光拡散シート1を備えた背面透過型ディスプレイ10の観察者は、ディスプレイの映像の明暗として認識し、明るさの均一性の極端に悪い映像を観察することになる。   An observer of the rear transmission display 10 including the light diffusion sheet 1 having the viewing angle characteristic having three luminance peaks as described above recognizes the brightness of the image on the display, and the uniformity of brightness is extremely poor. You will observe the video.

このような課題に対して、補助拡散層を付加した光拡散シート1が考案されている。図14にその基本構造の模式図を示す。   For such a problem, a light diffusion sheet 1 to which an auxiliary diffusion layer is added has been devised. FIG. 14 shows a schematic diagram of the basic structure.

高屈折率の光入射側樹脂層5と、光入射側樹脂層5の一方の面に互いに平行に複数配置された断面三角形状の低屈折率材料で形成された遮光体3と、光出射側基板2とが設けられた全反射方式の透過型スクリーンの基本構造において、複数の構成が提案されている(例えば、特許文献2参照)。   A light incident side resin layer 5 having a high refractive index, a light shielding body 3 made of a low refractive index material having a triangular cross section and arranged in parallel on one surface of the light incident side resin layer 5; A plurality of configurations have been proposed in the basic structure of a total reflection type transmissive screen provided with a substrate 2 (see, for example, Patent Document 2).

第1の従来例として、図14の基本構造に示す高屈折率透明樹脂材料の開口部6の直下の領域のみに拡散微粒子などで形成された拡散体の層を設けた構成がある。この構成は、一方の面に断面三角形の溝が平行に複数形成された高屈折率の光入射樹脂層5を形成し、その開口部6の真下のみに拡散体の層を印刷工法等で形成し、断面三角形状の溝に低屈折率材料の遮光材料を充填し、光出射側基板2を接合して製造される。この構成によれば、遮光体3の開口部6に直接入射する平行光及び遮光体3の傾斜面を反射した反射平行光が 開口部6を通過する際、開口部6の真下に配置された拡散体の層により、非平行光として出射されるようにして、視野角による明るさの均一性を向上するようにしている。   As a first conventional example, there is a configuration in which a diffuser layer formed of diffusion fine particles or the like is provided only in a region immediately below the opening 6 of the high refractive index transparent resin material shown in the basic structure of FIG. In this configuration, a light incident resin layer 5 having a high refractive index in which a plurality of grooves having a triangular cross section are formed in parallel on one surface is formed, and a diffuser layer is formed just below the opening 6 by a printing method or the like. Then, the groove having a triangular cross section is filled with a light-shielding material of a low refractive index material, and the light emission side substrate 2 is joined. According to this configuration, the parallel light directly incident on the opening 6 of the light shield 3 and the reflected parallel light reflected by the inclined surface of the light shield 3 are arranged directly below the opening 6 when passing through the opening 6. The diffuser layer emits the light as non-parallel light so as to improve the brightness uniformity according to the viewing angle.

第2の従来例としては、図14の基本構造に示す高屈折率透明樹脂の開口部6の真下に位置する光出射側基板2の上部に屈折構造体を埋め込むもので、屈折構造体は2つ以上の分散面に光を発散するレンズレットを設けた構成である。この構成は、一方の面に三角形の溝が平行に複数形成された高屈折率の光入射樹脂層5を形成し、三角形状の溝に低屈折率材料の遮光体材料を充填し、光出射側基板2に埋め込まれた屈折構造体を、高屈折率の光入射樹脂層5の開口部6の真下に配置し、光出射側基板2を接合して製造される。この構成によれば、遮光体3の開口部6に直接入射する平行光及び遮光体3の傾斜面を反射した反射平行光が 開口部6の出口に配置された拡散構造体により、非平行光として出射され、視野角による明るさの均一性を向上するようにしている。
実開昭50−121753号公報(図5) 特表2003−504691号公報(図20、図22)
As a second conventional example, a refractive structure is embedded in the upper part of the light emitting side substrate 2 located immediately below the opening 6 of the high refractive index transparent resin shown in the basic structure of FIG. In this configuration, a lenslet that diverges light is provided on at least two dispersion surfaces. In this configuration, a light incident resin layer 5 having a high refractive index in which a plurality of triangular grooves are formed in parallel on one surface is formed, a light shielding material of a low refractive index material is filled in the triangular grooves, and light is emitted. The refractive structure embedded in the side substrate 2 is disposed immediately below the opening 6 of the light incident resin layer 5 having a high refractive index, and the light emission side substrate 2 is joined. According to this configuration, the parallel light directly incident on the opening 6 of the light shield 3 and the reflected parallel light reflected from the inclined surface of the light shield 3 are non-parallel light by the diffusion structure disposed at the exit of the opening 6. And the brightness uniformity according to the viewing angle is improved.
Japanese Utility Model Publication No. 50-121753 (FIG. 5) Japanese translation of PCT publication No. 2003-504691 (FIGS. 20 and 22)

第1の従来例の構成では、開口部6の真下のみに拡散層が形成されているため、遮光体3の開口部6に直接入射する平行光及び遮光体3の傾斜面を反射した反射平行光とが開口部6の出口に配置された拡散体の層により、非平行光となって出射されるため、3つのピークゲインが各々緩和される。しかしながら、開口部6の直下への拡散粒子等で形成された印刷等による拡散体層では光拡散効果が非常に低く、3つの輝度ピークを解消し、ディスプレイ画面の明暗を解消するに至らないという問題があった。   In the configuration of the first conventional example, since the diffusion layer is formed only directly below the opening 6, the parallel light directly incident on the opening 6 of the light shield 3 and the reflection parallel reflected by the inclined surface of the light shield 3 are reflected. Since the light is emitted as non-parallel light by the diffuser layer disposed at the exit of the opening 6, the three peak gains are alleviated. However, the diffuser layer by printing or the like formed with diffusing particles or the like directly under the opening 6 has a very low light diffusion effect, which eliminates the three luminance peaks and does not eliminate the brightness of the display screen. There was a problem.

また、第2の従来例の構成では、開口部6の真下の光出射側基板2の位置に屈折構造体を埋め込む構成であり、具体的な拡散構造体の構造や拡散効果の説明の記載がなされていないものの、開口部6から出射する3つのピークゲインを比較的大きく緩衝できる可能性はある。しかしながら、製造工法において、光出射側基板2の屈折構造体の位置と、高屈折率の光入射樹脂層5の開口部6とを正確に位置あわせを行って両者の張り合わせを行うには、非常に難易度の高い技術が必要であり、張り合わせの位置ズレが発生しやすい。このような位置ズレが発生した場合、開口部6を通過した光が拡散構造体を透過する光と透過しない光が発生するなどして、安定した視野角特性が得られないという問題があった。   Further, in the configuration of the second conventional example, the refractive structure is embedded in the position of the light emitting side substrate 2 directly below the opening 6, and a description of a specific structure of the diffusion structure and a description of the diffusion effect is provided. Although not made, there is a possibility that the three peak gains emitted from the opening 6 can be relatively buffered. However, in the manufacturing method, in order to accurately align the position of the refractive structure of the light emitting side substrate 2 and the opening 6 of the light incident resin layer 5 having a high refractive index, Therefore, a technique with a high degree of difficulty is required, and misalignment is likely to occur. When such misalignment occurs, there is a problem in that stable viewing angle characteristics cannot be obtained because light that has passed through the opening 6 is transmitted through the diffusion structure and light that is not transmitted. .

本発明は、前記従来の課題を解決するもので、全反射型の光拡散シートにおいて、遮光体の開口部直上に球面屈折レンズを形成し、3つの輝度ピークの凹凸を解消し、視野角を変えながら映像を観察した場合でも観察者が違和感を覚えることの無い品質の高い光拡散シート及びそれを用いた透過型スクリーンを単純な製造工程で提供することを目的とする。   The present invention solves the above-mentioned conventional problems. In the total reflection type light diffusion sheet, a spherical refractive lens is formed immediately above the opening of the light shielding body, the unevenness of the three luminance peaks is eliminated, and the viewing angle is increased. An object of the present invention is to provide a high-quality light diffusing sheet and a transmission screen using the same, in which a viewer does not feel uncomfortable even when observing an image while changing, with a simple manufacturing process.

前記従来の課題を解決するために、本発明の透過型スクリーン用の光拡散シートは、透明基板の光出射側基板と、前記光出射側基板の一方の面に光透過部となる開口部を介在して配列される断面三角形状の遮光体と、断面三角形状の前記遮光体の傾斜面に設けられる第1の屈折率の透明樹脂層で形成される反射レンズと、隣接する前記遮光体の開口部に形成される当該第1の屈折率の透明樹脂層の球面屈折レンズと、前記反射レンズと前記球面屈折レンズを覆って前記第1の屈折率よりも高い第2の屈折率の透明樹脂層で形成される光入射側樹脂層とを備えたものである。   In order to solve the above-described conventional problems, a light diffusing sheet for a transmissive screen according to the present invention has a light emitting side substrate of a transparent substrate and an opening serving as a light transmitting portion on one surface of the light emitting side substrate. A light-shielding body having a triangular cross-section arranged in an intervening manner, a reflection lens formed of a transparent resin layer having a first refractive index provided on the inclined surface of the light-shielding body having a triangular cross-section, and an adjacent light-shielding body A spherical refractive lens of the transparent resin layer having the first refractive index formed in the opening, and a transparent resin having a second refractive index higher than the first refractive index covering the reflective lens and the spherical refractive lens. And a light incident side resin layer formed of layers.

また、本発明の透過型スクリーン用光拡散シートの製造方法は、透明基板の光出射側基板の一方の面に光透過部となる開口部を介在して配列される断面三角形状の遮光体を形成する第1の工程と、断面三角形状の前記遮光体の傾斜面に設けられる第1の屈折率の透明樹脂層で反射レンズを形成するとともに、隣接する前記遮光体の開口部に当該第1の屈折率の透明樹脂層の球面屈折レンズを形成する第2の工程と、前記第2の工程後、前記反射レンズと前記球面屈折レンズを覆って前記第1の屈折率よりも高い第2の屈折率の透明樹脂層で光入射側樹脂層を形成する第3の工程とを備えたものである。   The method for manufacturing a light diffusing sheet for a transmissive screen according to the present invention includes a light shielding body having a triangular cross section arranged on one surface of a light emitting side substrate of a transparent substrate with an opening serving as a light transmitting portion interposed therebetween. A reflection lens is formed by a first step of forming and a transparent resin layer having a first refractive index provided on an inclined surface of the light shielding body having a triangular cross section, and the first lens is formed in the opening of the adjacent light shielding body. A second step of forming a spherical refractive lens of a transparent resin layer having a refractive index of 2nd and a second refractive index higher than the first refractive index covering the reflective lens and the spherical refractive lens after the second step. And a third step of forming a light incident side resin layer with a transparent resin layer having a refractive index.

また、本発明の透過型スクリーン用の光拡散シートは、透明基板の光出射側基板と、前記光出射側基板の一方の面に光透過部となる開口部を介在して配列される断面三角形状の遮光体と、 隣接する前記遮光体の開口部に形成される第1の屈折率の透明樹脂層の球面屈折レンズと、前記遮光体と前記球面屈折レンズを覆って前記第1の屈折率よりも高い第2の屈折率の透明樹脂層で形成される光入射側樹脂層とを備え、前記遮光体が前記第2の屈折率の透明樹脂層より低い第3の屈折率の樹脂材料で形成され、前記遮光体の傾斜面が反射レンズとなるものである。   The light diffusing sheet for a transmissive screen according to the present invention includes a light emitting side substrate of a transparent substrate and a triangular cross section arranged on one surface of the light emitting side substrate with an opening serving as a light transmitting portion. A light shielding body having a shape; a spherical refractive lens of a transparent resin layer having a first refractive index formed in an opening of the adjacent light shielding body; and the first refractive index covering the light shielding body and the spherical refractive lens. A light incident side resin layer formed of a transparent resin layer having a higher second refractive index than the transparent resin layer having a third refractive index lower than the transparent resin layer having the second refractive index. The inclined surface of the light shielding body is formed as a reflection lens.

本発明の光拡散シート及びそれを用いた透過型スクリーンによれば、全反射型光拡散シートに強く現れる3つの輝度ピークによる凹凸を解消して、視野角を変えながら映像を観察した場合でも観察者が違和感を覚えることの無い画像を観察することができる。また、本発明は、左右方向に加え上下方向にも反射レンズを配置する上下視野角拡大構造においても有効に作用し、上下方向にも広い視野角が得られ、観察者が座ったり立ったりしたときの画面の明るさの変化が滑らかな画像が得られる。   According to the light diffusing sheet of the present invention and the transmissive screen using the same, the unevenness caused by the three luminance peaks that strongly appear in the total reflection type light diffusing sheet is eliminated, and observation is performed even when the image is observed while changing the viewing angle. It is possible to observe an image that the person does not feel uncomfortable. In addition, the present invention also works effectively in a vertical viewing angle expansion structure in which reflecting lenses are arranged in the vertical direction in addition to the horizontal direction, and a wide viewing angle is obtained in the vertical direction so that an observer can sit or stand. An image with a smooth change in screen brightness can be obtained.

以下に、本発明の透過型スクリーンの拡散シートの実施の形態を図面とともに詳細に説明する。   Embodiments of a transmissive screen diffusion sheet according to the present invention will be described below in detail with reference to the drawings.

(実施の形態1)
図1は、本発明の第1の実施の形態における透過型スクリーンの光拡散シート1について、断面構造図を示したものである。図1に示すように、光拡散シート1は、大きくは光出射側基板2と、遮光体3と、レンズ樹脂層4と光入射側樹脂層5とで構成される。
(Embodiment 1)
FIG. 1 shows a cross-sectional structure diagram of a light diffusing sheet 1 of a transmissive screen according to a first embodiment of the present invention. As shown in FIG. 1, the light diffusion sheet 1 is mainly composed of a light emission side substrate 2, a light shielding body 3, a lens resin layer 4, and a light incident side resin layer 5.

光出射側基板2は、基材として通常、屈折率1.49のPMMAあるいは屈折率1.52程度のMS樹脂(スチレンとMMAとの重合体)が用いられ、基材中には直径約10μm以下の拡散微粒子が10%前後の体積率で分散されている。この拡散微粒子としては、一般的に、屈折率が基材より高いMS樹脂からなるビーズが用いられる。上記基板及び拡散微粒子に用いるMS樹脂材料の屈折率は、屈折率約1.49のMMA樹脂と、屈折率約1.59のスチレン樹脂の配合比率を変えることで、1.49から1.59の範囲で調整可能である。   The light emission side substrate 2 is usually made of PMMA having a refractive index of 1.49 or MS resin (polymer of styrene and MMA) having a refractive index of about 1.52 as a base material, and has a diameter of about 10 μm in the base material. The following diffusion fine particles are dispersed at a volume ratio of about 10%. As the diffusion fine particles, beads made of MS resin having a refractive index higher than that of the base material are generally used. The refractive index of the MS resin material used for the substrate and the diffusing fine particles is changed from 1.49 to 1.59 by changing the blending ratio of MMA resin having a refractive index of about 1.49 and styrene resin having a refractive index of about 1.59. It can be adjusted within the range.

このような拡散微粒子は、光出射側基板2への入射光を全方位に均等に拡散し出射する作用を有し、視野角曲線の均一化及びシンチレーションの低減などの改善効果がある一方で透過率低下を導くので、最適な粒子の材料、直径、含有率が選択される。この拡散微粒子は、基板厚み方向に分布率を変えて混合したり、拡散微粒子含有率の極めて高いシートを形成し、ピュアーな透明樹脂基板と貼り付けるなど各種の構成が考えられている。   Such diffusing fine particles have a function of uniformly diffusing and emitting incident light to the light emission side substrate 2 in all directions, and have an improvement effect such as uniform viewing angle curve and reduction of scintillation, while being transmitted. As this leads to a reduction in the rate, the optimal particle material, diameter and content are selected. Various configurations such as mixing the diffusion fine particles by changing the distribution rate in the thickness direction of the substrate, forming a sheet having a very high diffusion fine particle content, and pasting the pure transparent resin substrate are considered.

遮光体3は、基材として熱硬化性又は2液硬化性、EB硬化性のポリウレタン系樹脂などが用いられ、基材中には光吸収性のある黒色の顔料微粒子が分散されている。遮光体2の断面形状は、光出射側基板2に密着した底部を有し光入射面側に頂角を有する二等辺三角形の形状としてある。また、遮光体3は、開口部6を間に設けて均等間隔で複数平行配列され、断面奥行き方向に連続してある。   The light-shielding body 3 uses a thermosetting, two-component curable, or EB-curable polyurethane resin as a base material, and light-absorbing black pigment fine particles are dispersed in the base material. The cross-sectional shape of the light shielding body 2 is an isosceles triangle shape having a bottom portion in close contact with the light emitting side substrate 2 and having an apex angle on the light incident surface side. Further, the light shields 3 are arranged in parallel at equal intervals with the openings 6 therebetween, and are continuous in the cross-sectional depth direction.

光入射側樹脂層5で使用される樹脂の屈折率より低い低屈折率透明樹脂を材料とし、遮光体3の表面及び開口部6の表面に塗布してレンズ樹脂層4を形成する。例えば、シリコンやフッ素系が導入された低屈折率のアクリレート系樹脂などが用いられる。ここで、レンズ樹脂層4とは、反射層を形成する遮光体3の傾斜面の表面と、球面屈折層を形成する開口部6の表面との両方に隙間なく形成されてある連続した低屈折率透明樹脂層を示している。反射層を形成する遮光体3の三角形状の傾斜面には低屈折率透明層が約1μmの薄膜状に形成されてあり、反射レンズ7として機能する。また、球面屈折層を形成する遮光体3の断面三角形の脚部に挟まれた開口部6には光出射方向に凸の球面レンズ状に形成されてあり、球面屈折レンズ8として機能する。   A lens resin layer 4 is formed by applying a low refractive index transparent resin lower than the refractive index of the resin used in the light incident side resin layer 5 to the surface of the light shielding body 3 and the surface of the opening 6. For example, a low refractive index acrylate resin into which silicon or fluorine is introduced is used. Here, the lens resin layer 4 is a continuous low refractive index formed without a gap on both the surface of the inclined surface of the light-shielding body 3 forming the reflective layer and the surface of the opening 6 forming the spherical refractive layer. A transparent resin layer is shown. A low-refractive-index transparent layer is formed in a thin film of about 1 μm on the triangular inclined surface of the light-shielding body 3 forming the reflection layer, and functions as the reflection lens 7. Further, the opening 6 sandwiched between the legs of the cross-sectional triangle of the light blocking body 3 forming the spherical refractive layer is formed in a spherical lens shape convex in the light emitting direction, and functions as the spherical refractive lens 8.

即ち、遮光体3の傾斜部のレンズ樹脂層4は反射レンズ7としての機能を有し、開口部6の上部のレンズ樹脂層4は球面屈折レンズ8の機能を有し、反射レンズ7と球面屈折レンズ8は、連続したレンズ樹脂層4から形成されている。   That is, the lens resin layer 4 at the inclined portion of the light shield 3 has a function as the reflection lens 7, and the lens resin layer 4 at the upper portion of the opening 6 has the function of the spherical refraction lens 8. The refractive lens 8 is formed from a continuous lens resin layer 4.

光入射側樹脂層5は、レンズ樹脂層4の低屈折率透明樹脂より高い屈折率を示す高屈折率透明樹脂を材料とし、例えば、紫外線硬化性アクリレート系樹脂などが用いられる。そして、レンズ樹脂層4の表面全体を覆い、光入射側が光出射側基板2の表面と平行な平坦面としてある。   The light incident side resin layer 5 is made of a high refractive index transparent resin having a higher refractive index than the low refractive index transparent resin of the lens resin layer 4, and for example, an ultraviolet curable acrylate resin or the like is used. The entire surface of the lens resin layer 4 is covered, and the light incident side is a flat surface parallel to the surface of the light emitting side substrate 2.

図1において、間隔Pは、遮光体3の断面三角形状の頂点(頂上が平坦になっている時は、その中心点)と隣接の遮光体3の断面三角形状の頂点との間隔であり、光拡散シート1の構成上の単セルに相当する。遮光体3と隣接の遮光体3との間の中心線は、屈折レンズ8の球面の中心線と一致し、この中心線は単セル内での対称線にも相当する。この単セルにおいて、中心線から左側を領域I、右側を領域IIとする。そして、領域Iにおける遮光体3の傾斜面に形成された低屈折率透明樹脂の薄膜領域を領域biとし、入射光を全反射する機能を有する反射レンズ7に相当する領域である。領域IIにおける遮光体3の傾斜面に形成された低屈折率透明樹脂の薄膜領域を領域biiとし同様に反射レンズ7にと同様の機能領域である。さらに、領域aは開口部6に設けられた球面状の低屈折率透明樹脂であり入射光を屈折透過する機能を有する球面屈折レンズ8に相当する領域である。   In FIG. 1, the interval P is the interval between the apexes of the cross-sectional triangle shape of the light shield 3 (the center point when the top is flat) and the apex of the cross-sectional triangle shape of the adjacent light shield 3. This corresponds to a single cell on the configuration of the light diffusion sheet 1. The center line between the light shield 3 and the adjacent light shield 3 coincides with the center line of the spherical surface of the refractive lens 8, and this center line also corresponds to a symmetric line in the single cell. In this single cell, the left side from the center line is a region I, and the right side is a region II. The thin film region of the low refractive index transparent resin formed on the inclined surface of the light shield 3 in the region I is a region bi, and corresponds to the reflection lens 7 having a function of totally reflecting incident light. The thin film region of the low refractive index transparent resin formed on the inclined surface of the light shielding body 3 in the region II is a region bii, which is the same functional region as the reflective lens 7. Further, the region a is a spherical low refractive index transparent resin provided in the opening 6 and corresponds to the spherical refractive lens 8 having a function of refracting and transmitting incident light.

これら、反射レンズ7の全反射機能と球面屈折レンズ8の光屈折機能とを得るために遮光体3とレンズ樹脂層4とは各々において次の条件で形成してある。   In order to obtain the total reflection function of the reflection lens 7 and the light refraction function of the spherical refraction lens 8, the light shielding body 3 and the lens resin layer 4 are formed under the following conditions, respectively.

低屈折率透明樹脂層と高屈折率透明樹脂層とが密着形成された基板に対し、高屈折率透明樹脂層側から、低屈折率透明樹脂表面の垂線とのなす角度(入射角)で平行光を入射すると、臨界角度以上の入射角度で平行光を入射すると全反射を起こし、臨界角度以下で平行光を入射すると屈折透過を起こす。そして、この臨界角度は、低屈折率透明樹脂層と高屈折率透明樹脂層との屈折率の比率で決定される値である。   Parallel to the substrate on which the low-refractive-index transparent resin layer and the high-refractive-index transparent resin layer are formed in close contact with each other from the high-refractive-index transparent resin layer side to the perpendicular to the low-refractive-index transparent resin surface (incident angle) When light is incident, total reflection occurs when parallel light is incident at an incident angle greater than the critical angle, and refractive transmission occurs when parallel light is incident at a critical angle or less. The critical angle is a value determined by the ratio of the refractive indexes of the low refractive index transparent resin layer and the high refractive index transparent resin layer.

したがって、反射レンズ7は、断面三角形状の遮光体3の傾斜面の法線と光入射側樹脂層5の平坦面に垂直に入射される平行光とでなす角(即ち遮光体3の傾斜面への光入射角度)が、遮光体3の傾斜面に対し臨界角度以上の角度になる条件で形成してある。例えば、低屈折率透明樹脂の屈折率1.45、高屈折率透明樹脂1.55の場合、臨界角度は約70°となるため、入射角度が70°以上になるように遮光体3の傾斜面角度が設けられる。この入射角度は、遮光体3の底辺と傾斜面のなす角度θに相当する。このような条件で構成されたレンズ樹脂層4の領域biとbiiが反射レンズ7となっている。   Therefore, the reflection lens 7 has an angle formed by the normal of the inclined surface of the light shielding body 3 having a triangular cross section and parallel light incident perpendicularly to the flat surface of the light incident side resin layer 5 (that is, the inclined surface of the light shielding body 3). The light incident angle on the light shielding body 3 is formed on the condition that the angle is greater than the critical angle with respect to the inclined surface of the light shield 3. For example, in the case of the refractive index 1.45 of the low refractive index transparent resin and the high refractive index transparent resin 1.55, since the critical angle is about 70 °, the light shielding body 3 is inclined so that the incident angle is 70 ° or more. A surface angle is provided. This incident angle corresponds to the angle θ formed by the bottom surface of the light shield 3 and the inclined surface. The regions bi and bii of the lens resin layer 4 configured under such conditions serve as the reflection lens 7.

一方、開口部6に相当する領域aにある球面状のレンズ樹脂層では、光入射側基板の高屈折率透明樹脂から入射された平行光の入射角度が、全反射角度以下になるように形成してあり、球面屈折レンズ8の表面で入射光を集光する方向に屈折し、開口部6から出射され、光出射基板2内部で焦点を結んだ後、光が拡散される。   On the other hand, the spherical lens resin layer in the region a corresponding to the opening 6 is formed so that the incident angle of the parallel light incident from the high refractive index transparent resin on the light incident side substrate is less than the total reflection angle. Then, the light is refracted in the direction of condensing incident light on the surface of the spherical refractive lens 8, emitted from the opening 6, focused in the light emitting substrate 2, and then diffused.

つぎに、光拡散シート1の製造方法を大きく3つの工程に分けて説明する。第1の工程では、光出射側基板2に遮光体3を形成する。基材より屈折率の高い透明樹脂にガラス又は樹脂の球状微粒子を混合分散して押し出し成形などで形成された厚さ1〜3mmの光出射側基板2表面に、数パーセントのカーボン微粒子を含む低屈折率透明樹脂を、開口部6の間隔を置いて断面三角形状の遮光体3を複数平行配列して形成する。この遮光体3は、表面に離型処理された断面三角形の溝が設けられた金型に樹脂を充填すると同時に、過熱或いは化学反応、エレクトロンビームなどで重合硬化して成形される。   Next, the method for manufacturing the light diffusing sheet 1 will be described in three steps. In the first step, the light shielding body 3 is formed on the light emitting side substrate 2. A glass containing resin or spherical fine particles mixed with a transparent resin having a higher refractive index than that of the base material and formed by extrusion or the like, and the surface of the light emitting side substrate 2 having a thickness of 1 to 3 mm contains a few percent of carbon fine particles. A refractive index transparent resin is formed by arranging a plurality of light blocking bodies 3 having a triangular cross section at intervals of the openings 6 in parallel. The light-shielding body 3 is molded by being filled with resin in a mold provided with a groove having a triangular cross-section on the surface, and at the same time being polymerized and cured by overheating, chemical reaction, electron beam, or the like.

第2の工程では、レンズ樹脂層4を形成する。まず、開口部6と遮光体3の表面へ、低屈折率の紫外線硬化透明樹脂の液体を定量塗布する。塗布量が微量である場合、液体塗布を多くして制御性を向上したい場合は、溶剤で紫外線硬化透明樹脂を希釈して塗布した後に溶剤を除去してもよい。塗布した紫外線硬化透明液体は、遮光体3の表面に薄膜を形成すると共に、遮光体3の脚部間の開口部6には、樹脂液体の表面張力によりメニスカス球面が形成される。次に、これら液面によって形成された樹脂膜を紫外線照射により硬化し、レンズ樹脂層4を形成する。   In the second step, the lens resin layer 4 is formed. First, a liquid of a low refractive index ultraviolet curable transparent resin is quantitatively applied to the surfaces of the opening 6 and the light shielding body 3. When the coating amount is very small, when it is desired to increase the liquid coating and improve the controllability, the solvent may be removed after the UV curable transparent resin is diluted with the solvent and applied. The applied ultraviolet curable transparent liquid forms a thin film on the surface of the light shielding body 3, and a meniscus spherical surface is formed in the opening 6 between the leg portions of the light shielding body 3 due to the surface tension of the resin liquid. Next, the resin film formed by these liquid surfaces is cured by ultraviolet irradiation to form the lens resin layer 4.

第3の工程では、光入射側樹脂層5を形成する。レンズ樹脂層4の上から、高屈折率の紫外線硬化透明樹脂を塗布して、三角形状の遮光体3の凹凸を完全に埋め、平坦面を形成し、その後、紫外線を照射して固化する。   In the third step, the light incident side resin layer 5 is formed. An ultraviolet curable transparent resin having a high refractive index is applied from above the lens resin layer 4 to completely fill the irregularities of the triangular light shield 3 to form a flat surface, and then solidify by irradiation with ultraviolet rays.

上記第2の工程におけるレンズ樹脂層4の形成において、低屈折率樹脂液体を塗布して、遮光体3の傾斜面への薄膜形成(反射レンズ7)と開口部6への凹型球面の形成(球面屈折レンズ8)を同時におこなうためには、遮光体3の傾斜面と開口部6の表面との両方の領域全面が、低屈折率樹脂液体によって濡れた状態になることが必要である。一般に、固体と液体の濡れの指標として、接触角の値が用いられ、大きく分けて、90°より高いと固体表面を液体が弾き、90°より低いと濡れると表現される。底を閉じ垂直に立てた円柱管に液体を入れたとき、管内の対向する壁面が平行であれば接触角90°で水平液面となり、90°より低いと管表面と液体の接点に形成される接触角に沿って凹型のメニスカス液面が形成される。同様な原理により、対向する遮光体3の傾斜面の内側の液面が水平になる条件は、遮光体3の傾斜角度と接触角とが同じ値になる場合であり、開口部6に凹面レンズを形成するためには、この傾斜角度より低い接触角であれば良い。   In the formation of the lens resin layer 4 in the second step, a low refractive index resin liquid is applied to form a thin film on the inclined surface of the light shielding body 3 (reflection lens 7) and a concave spherical surface on the opening 6 ( In order to perform the spherical refraction lens 8) at the same time, it is necessary that the entire area of both the inclined surface of the light shield 3 and the surface of the opening 6 be wetted by the low refractive index resin liquid. In general, the value of the contact angle is used as an indicator of the wettability between the solid and the liquid. Roughly speaking, it is expressed that the liquid repels the surface of the solid when it is higher than 90 ° and wet when it is lower than 90 °. When the liquid is put into a cylindrical tube with the bottom closed and standing vertically, if the opposing wall surfaces in the tube are parallel, a horizontal liquid surface is obtained at a contact angle of 90 °, and if it is lower than 90 °, it is formed at the contact point between the tube surface and the liquid. A concave meniscus liquid level is formed along the contact angle. Based on the same principle, the condition that the liquid surface inside the inclined surface of the opposing light shielding body 3 becomes horizontal is that the inclination angle and the contact angle of the light shielding body 3 have the same value. In order to form the contact angle, the contact angle may be lower than the inclination angle.

図2は、対向する遮光体3の傾斜面の間に液体を入れたときに形成されるメニスカス液面の模式図である。遮光体3の傾斜面と低屈折率樹脂液体との接点に形成される接触角ωの液面に沿って球面が形成される。   FIG. 2 is a schematic view of a meniscus liquid surface formed when a liquid is put between the inclined surfaces of the opposing light shielding body 3. A spherical surface is formed along the liquid surface of the contact angle ω formed at the contact point between the inclined surface of the light shielding body 3 and the low refractive index resin liquid.

一方、遮光体3の傾斜面に低屈折率樹脂液体の薄膜を形成するためには、傾斜面上でこの液体が弾かずに液体の層が安定して形成されることが必要である。一般に、固体(特に有機化合物)の臨界表面張力より表面張力の小さい液体は、すべてこの固体表面の上をひろがることが知られている。例えば、PMMA(ポリメチルメタクリレート)の表面を液体で濡らせたいときは、PMMAの臨界表面張力39dyn/cmより低い液体を調整して用いれば良い。紫外線硬化性樹脂の液体は、アクリル系及びエポキシ系など各種製品から適した材料を選択するか、調整して得られる。また、フッ素系樹脂など、臨界表面張力の非常に低い材料の場合は、固体表面へオゾンアッシング処理を行うことで表面が活性化して液体の濡れやすくすることも可能である。これは、大気圧上でオゾンへ紫外線を照射するなどして、酸素ラジカルを生成して固体表面をアッシングする処理をいい、有機材料の有機結合が切断され酸素を含んだ官能基が形成され極めて活性に富んだ表面状態が得られる。   On the other hand, in order to form a thin film of low refractive index resin liquid on the inclined surface of the light shielding body 3, it is necessary that the liquid layer be stably formed without repelling this liquid on the inclined surface. In general, it is known that any liquid having a surface tension smaller than the critical surface tension of a solid (particularly an organic compound) spreads on the surface of the solid. For example, when it is desired to wet the surface of PMMA (polymethylmethacrylate) with a liquid, a liquid having a lower surface tension than the PMMA critical surface tension of 39 dyn / cm may be used. The liquid of the ultraviolet curable resin can be obtained by selecting or adjusting a suitable material from various products such as acrylic and epoxy. In addition, in the case of a material having a very low critical surface tension such as a fluorine-based resin, it is possible to activate the surface by performing ozone ashing treatment on the solid surface, thereby making it easy to wet the liquid. This is a process of ashing the solid surface by generating oxygen radicals by irradiating ultraviolet rays to ozone at atmospheric pressure, etc., and the organic group of the organic material is cleaved to form a functional group containing oxygen. A surface state rich in activity is obtained.

このようにして固体表面の臨界表面張力を上げれば、ほとんどの液体を固体表面で濡れ広がせることができ、液体の表面層を形成することができる。このように臨界表面張力を基準に遮光体3の傾斜面と低屈折率材料液体を選定及び調整した。本実施の形態では、現実的な方法として、臨界表面張力以下の液体の定義を、遮光体3の材料表面で濡れ状態が保持されることで判断した。一方、遮光体3の傾斜面及び開口部6が低屈折率樹脂材料液体で濡れ状態にあるとき、遮光体3の傾斜面は低屈折率樹脂材料液体との接触角が0に等しくなり、開口部6に形成されるメニスカス液面形状は、曲率半径の最も小さな凹型の球面となる。このように、遮光体3の傾斜面の臨界表面張力より小さい低屈折率樹脂材料液体を用いることで、図1に示すような遮光体3の傾斜面の薄膜と、開口部6の球面屈折レンズ8を形成した。本実施の形態では、また、遮光体3の傾斜面の低屈折率材料の膜厚は、樹脂液体の粘度に相関があり、樹脂液体の粘度を選択調整して所望の膜厚を得ることが可能である。   If the critical surface tension of the solid surface is increased in this way, most liquid can be wetted and spread on the solid surface, and a liquid surface layer can be formed. Thus, the inclined surface of the light shielding body 3 and the low refractive index material liquid were selected and adjusted based on the critical surface tension. In the present embodiment, as a practical method, the definition of a liquid having a critical surface tension or less is determined by maintaining a wet state on the material surface of the light blocking body 3. On the other hand, when the inclined surface of the light shielding body 3 and the opening 6 are in a wet state with the low refractive index resin material liquid, the inclined surface of the light shielding body 3 has a contact angle with the low refractive index resin material liquid equal to 0, The meniscus liquid surface shape formed in the portion 6 is a concave spherical surface having the smallest curvature radius. In this way, by using a low refractive index resin material liquid that is smaller than the critical surface tension of the inclined surface of the light shielding body 3, the thin film of the inclined surface of the light shielding body 3 as shown in FIG. 8 was formed. In the present embodiment, the film thickness of the low refractive index material on the inclined surface of the light shielding body 3 has a correlation with the viscosity of the resin liquid, and a desired film thickness can be obtained by selectively adjusting the viscosity of the resin liquid. Is possible.

以上のようなレンズ形成の工法を用いることで、高価で成形困難な金型成形を用いることなく、遮光体3の表面の反射レンズ7と開口部6の超微細な球面屈折レンズ8とを同時に形成し、特別な位置調整機構を用いることなく遮光体3と球面屈折レンズ8の確実な位置合わせがセルフアライメントで達成できるため、高精度で安価な製造工法を提供するものである。   By using the lens forming method as described above, the reflection lens 7 on the surface of the light shield 3 and the ultrafine spherical refraction lens 8 in the opening 6 can be simultaneously formed without using expensive and difficult mold forming. Thus, a reliable alignment between the light shield 3 and the spherical refractive lens 8 can be achieved by self-alignment without using a special position adjusting mechanism, and therefore, a highly accurate and inexpensive manufacturing method is provided.

また、上記のようなオゾンアッシング処理をレンズ樹脂層4の表面層に施せば、レンズ樹脂層4と光入射側樹脂層5の接着力の強化、及びレンズ樹脂層4の凹凸面への高屈折率樹脂材料液体の充填性向上に非常に有効である。   Further, if the above-described ozone ashing treatment is applied to the surface layer of the lens resin layer 4, the adhesion between the lens resin layer 4 and the light incident side resin layer 5 is enhanced, and the lens resin layer 4 is highly refracted onto the uneven surface. This is very effective in improving the filling property of the resin material liquid.

次に、本発明の第1の実施例における透過型スクリーン用拡散シート1の動作について、図3を用いて説明する。図3は、光入射側樹脂層5の平坦面に垂直に入射する平行光9が、遮光体3の開口部6の上にある球面屈折レンズ8に直接入射する時の動作を示している。光入射樹脂基板5の高屈折率樹脂へ入射した平行光9は、そのまま直進し、低屈折率樹脂で形成された球面屈折レンズ8の表面に達すると光が集光方向に屈折し、開口部6を通過して、光出射側基板2内で集光拡散し非平行光となって光出射側基板2の表面から出射される。このときの拡散角度は、高屈折率樹脂と低屈折率樹脂の屈折率差及び球面屈折レンズ8の曲率半径に依存し、屈折率差が高く、曲率半径が大きいほど出斜光の拡散効果が大きくなる。   Next, the operation of the transmissive screen diffusion sheet 1 according to the first embodiment of the present invention will be described with reference to FIG. FIG. 3 shows the operation when the parallel light 9 incident perpendicularly to the flat surface of the light incident side resin layer 5 directly enters the spherical refractive lens 8 above the opening 6 of the light shield 3. The parallel light 9 incident on the high refractive index resin of the light incident resin substrate 5 travels straight and reaches the surface of the spherical refractive lens 8 formed of the low refractive index resin, and the light is refracted in the light condensing direction. 6, the light is condensed and diffused in the light emission side substrate 2 to become non-parallel light and is emitted from the surface of the light emission side substrate 2. The diffusion angle at this time depends on the refractive index difference between the high refractive index resin and the low refractive index resin and the radius of curvature of the spherical refractive lens 8, and the higher the refractive index difference, the larger the curvature radius. Become.

従来、開口部6へ直接入射した光は、拡散することなく通過するか、光出射側基板2の内部の拡散剤により僅かに拡散するのみであったが、開口部6に球面屈折レンズ8を配置した本発明によれば、開口部6に直接入射される平行光を高効率で拡散することができる。   Conventionally, light directly incident on the opening 6 passes through without being diffused or is only slightly diffused by a diffusing agent inside the light emitting side substrate 2. According to the arranged present invention, parallel light directly incident on the opening 6 can be diffused with high efficiency.

次に、図4は、光入射側樹脂層5の平坦面に垂直に入射する平行光9が、遮光体3の傾斜部上に設けられた反射レンズ7に照射された場合の動作を説明する。反射レンズ7は、遮光体3の開口部6の中心軸に対称且つ対向して設けられているので、ここでは片側の領域IIに相当する反射レンズ7の動作のみ説明する。図4に示すように、領域IIの反射レンズ7の領域biiに入射平行光9が照射された時に、光出射側基板2の内部に出射されるまでの光線の軌跡を光線h、光線fに示す。   Next, FIG. 4 illustrates an operation in the case where the parallel light 9 incident perpendicularly to the flat surface of the light incident side resin layer 5 is applied to the reflection lens 7 provided on the inclined portion of the light shield 3. . Since the reflection lens 7 is provided symmetrically and opposed to the central axis of the opening 6 of the light shield 3, only the operation of the reflection lens 7 corresponding to the region II on one side will be described here. As shown in FIG. 4, when the region bii of the reflecting lens 7 in the region II is irradiated with the incident parallel light 9, the trajectory of the light until it is emitted to the inside of the light emitting side substrate 2 is a light ray h and a light ray f. Show.

遮光体3の三角形頂点近傍の反射レンズ7に高屈折率透明樹脂材料から入射した光線fは、反射レンズ7の面で反射した後、領域I側の球面屈折レンズ8の表面に入射し、中心軸側に集光方向に屈折し、開口部6を透過して光出射側基板2へ出射する。一方、遮光体3の脚部近傍の反射レンズ7に照射された光線hは、反射レンズ7の表面で反射し、領域IIの球面屈折レンズ8で大きく中心軸から遠ざかる方向へ大きく屈折し、開口部6を透過して光出射側基板2へ出射する。   The light beam f incident from the high refractive index transparent resin material on the reflection lens 7 in the vicinity of the vertex of the triangle of the light shield 3 is reflected by the surface of the reflection lens 7 and then enters the surface of the spherical refraction lens 8 on the region I side. The light is refracted in the condensing direction toward the axis, passes through the opening 6, and exits to the light exit side substrate 2. On the other hand, the light beam h applied to the reflection lens 7 in the vicinity of the leg portion of the light shield 3 is reflected by the surface of the reflection lens 7 and refracted greatly in the direction away from the central axis by the spherical refraction lens 8 in the region II. The light passes through the portion 6 and is emitted to the light emission side substrate 2.

このように反射レンズ7に入射平行光が照射される場合においても、球面レンズ8が設けてあることで、遮光体3の三角形頂点近傍に照射された光(光線f)は、より低視野角側へ移動し、遮光体3の三角形脚部近傍に照射された光(光線h)は、より高視野角側へ移動するため、反射レンズ7の反射光が低視野角側と高視野角側の両方により大きな広がりを持って出射側基板2へ出射される。また、遮光体3の三角形状の傾斜面を曲面とし非平行光を作成した場合においても、このような球面屈折レンズ8があることで、拡散効果が高まり、視野角曲線のピークの緩和効果が高まると共に、高視野角側の裾野をより広げる効果がある。   As described above, even when the incident parallel light is irradiated onto the reflection lens 7, the light (light ray f) irradiated in the vicinity of the vertex of the triangle of the light shield 3 has a lower viewing angle because the spherical lens 8 is provided. Since the light (ray h) irradiated to the vicinity of the triangular leg portion of the light shield 3 moves to the higher viewing angle side, the reflected light of the reflection lens 7 is reflected on the lower viewing angle side and the higher viewing angle side. In both cases, the light is emitted to the emission side substrate 2 with a large spread. Further, even when non-parallel light is created by using the triangular inclined surface of the light shield 3 as a curved surface, the presence of such a spherical refractive lens 8 enhances the diffusion effect and reduces the peak of the viewing angle curve. As it increases, it has the effect of further widening the base on the high viewing angle side.

図5に拡散粒子を含有する光出射側基板2を通過する前の視野角曲線Cbと通過した後の視野角曲線Cfを示す。光出射側基板2を通過する前の曲線Cbにおいて、ピークgcは遮光体開口部6の領域aに直接入射した光のゲインであり、ピークgs及びピークgs’は反射レンズ7の領域bi、biiで反射された光のゲイン特性を示す。従来の球面屈折レンズ8の無いゲイン特性に比べ、3つのゲインピークが大きく拡散することで、曲線Cfに示すように、一般的な拡散粒子を含有した光出射側基板2を透過させると、3つのピークが解消される。このように、本発明を適用した場合、視野角曲線の凹凸が無く、広い視野角性能を有する特性を得ることができる。   FIG. 5 shows a viewing angle curve Cb before passing through the light emitting side substrate 2 containing diffusing particles and a viewing angle curve Cf after passing through. In the curve Cb before passing through the light emitting side substrate 2, the peak gc is the gain of the light directly incident on the region a of the light shield opening 6, and the peaks gs and gs ′ are the regions bi and bii of the reflection lens 7. The gain characteristic of the light reflected by is shown. Compared with the gain characteristic without the conventional spherical refraction lens 8, when the three gain peaks are diffused greatly, as shown by the curve Cf, when passing through the light emitting side substrate 2 containing general diffusion particles, 3 One peak is eliminated. Thus, when the present invention is applied, there is no unevenness of the viewing angle curve, and a characteristic having a wide viewing angle performance can be obtained.

以上のように、開口部6に球面屈折レンズ8を配置することで、開口部6及び遮光体3の領域に入射した平行光9は、両方の領域から発生する輝度ピークを緩和し、ゲインの裾野を広げられるため、一般的な拡散機能つきの光出射側基板2を通過した後は、3つの輝度ピークの分離が解消され、高視野角側に裾野の広い特性が得られ、高品質な光透過型スクリーンの光拡散シート1を提供できるものである。   As described above, by arranging the spherical refractive lens 8 in the opening 6, the parallel light 9 incident on the area of the opening 6 and the light shielding body 3 relaxes the luminance peak generated from both areas, and the gain is reduced. Since the base can be expanded, after passing through the light emitting side substrate 2 with a general diffusion function, the separation of the three luminance peaks is eliminated, and a wide base is obtained on the high viewing angle side, so that high quality light is obtained. The light diffusing sheet 1 of a transmissive screen can be provided.

上記の第1の実施例では、反射レンズ7の形成に、遮光体3の上面に塗布した第1の屈折率の透明樹脂層と第2の屈折率の透明樹脂層の全反射境界を用いたが、遮光体3を前記第2の屈折率の透明樹脂層より低い第3の屈折率の樹脂材料で形成し、遮光体3及び開口部の球面屈折レンズの上部に第2の屈折率の透明樹脂層を形成し、遮光体3の傾斜面と第2の屈折率の透明樹脂層との境界で反射レンズを形成することもできる。ここで、開口部に形成する球面屈折レンズは、100cps前後の比較的粘度の低い第1の屈折率の透明樹脂材料液体を遮光層及び開口部上に適量塗布して形成する。粘度の低い透明樹脂液体は、遮光層3の傾斜面をすべり落ちて開口部に溜り凹型液面(凹型メニスカス)を形成する。また、第1の屈折率の透明樹脂材料液体の塗布には、インクジェットによって開口部に適量塗布することもできる。さらに、第1と第3の屈折率の透明樹脂は、同じ屈折率となる材料であっても良い。   In the first embodiment, the reflection lens 7 is formed using the total reflection boundary between the transparent resin layer having the first refractive index and the transparent resin layer having the second refractive index applied to the upper surface of the light shield 3. However, the light shielding body 3 is formed of a resin material having a third refractive index lower than that of the transparent resin layer having the second refractive index, and the second refractive index is transparent on the light shielding body 3 and the spherical refractive lens in the opening. A resin layer may be formed, and a reflection lens may be formed at the boundary between the inclined surface of the light shield 3 and the transparent resin layer having the second refractive index. Here, the spherical refractive lens formed in the opening is formed by applying an appropriate amount of a transparent resin material liquid having a relatively low first refractive index of about 100 cps on the light shielding layer and the opening. The transparent resin liquid having a low viscosity slides down the inclined surface of the light shielding layer 3 and accumulates in the opening to form a concave liquid surface (concave meniscus). In addition, for the application of the transparent resin material liquid having the first refractive index, an appropriate amount can be applied to the opening by inkjet. Furthermore, the transparent resin having the first and third refractive indexes may be a material having the same refractive index.

(実施の形態2)
次に、本発明の第2の実施の形態における透過型スクリーンの光拡散シート1について説明する。この第2の実施例は、左右と上下の両方の方向に視野角の拡大を行うものである。図6は、本発明の第2の実施例における透過型スクリーンの光拡散シート1の上面図を示したものである。図7は、図6のA−A’切断面の構造図である。図8は、図6のB−B’切断面の構造図である。
(Embodiment 2)
Next, a light diffusing sheet 1 for a transmissive screen according to a second embodiment of the present invention will be described. In the second embodiment, the viewing angle is expanded in both the left and right and top and bottom directions. FIG. 6 shows a top view of the light diffusing sheet 1 of the transmission screen in the second embodiment of the present invention. FIG. 7 is a structural diagram of the AA ′ cut surface of FIG. FIG. 8 is a structural diagram of the BB ′ cut surface of FIG.

本発明の第1の実施の形態では、断面三角形状の遮光体3が、奥行き方向に連続しストライプ状に形成されていたのに対し、第2の実施の形態では、図6の光拡散シート1の上面図に示すように、遮光体3が従来の左右方向への配列に加えて、上下方向にも奥行き方向に連続形成されており、左右と上下に配列された遮光体3の交点部で接続された構成になっている。従って、開口部6は上面からみると島状に個々に分離されており、遮光体3の傾斜面が島状の開口部6を四方で囲むような擂り鉢状の構成である。この1つの擂り鉢状が単セルとなる。   In the first embodiment of the present invention, the light shielding body 3 having a triangular cross section is formed in a stripe shape that is continuous in the depth direction, whereas in the second embodiment, the light diffusion sheet of FIG. 1, in addition to the conventional arrangement in the left-right direction, the light-shielding bodies 3 are continuously formed in the vertical direction in the depth direction, and the intersections of the light-shielding bodies 3 arranged in the left-right and up-down directions It is configured to be connected with. Accordingly, the openings 6 are separated into islands when viewed from above, and the inclined surface of the light shield 3 has a bowl-like configuration in which the island-like openings 6 are surrounded on four sides. This one bowl shape becomes a single cell.

ここで、A−A’断面の構成は左右方向視野角に、B−B’断面の構成は上下方向視野角に関連する。上下方向視野角より左右方向視野角を重視する場合は、上下方向断面の遮光体3のピッチを大きくとり反射レンズ7への入射光照射面積比率を低くすることで調整できる。図8の遮光体3のピッチPvを図7のピッチPhより大きくしているのは、左右方向視野角を重視した例に相当する。   Here, the configuration of the A-A ′ section relates to the horizontal viewing angle, and the configuration of the B-B ′ section relates to the vertical viewing angle. In the case where the horizontal viewing angle is more important than the vertical viewing angle, it can be adjusted by increasing the pitch of the light shields 3 in the vertical cross section and reducing the incident light irradiation area ratio to the reflection lens 7. The fact that the pitch Pv of the light shield 3 in FIG. 8 is larger than the pitch Ph in FIG. 7 corresponds to an example in which the horizontal viewing angle is emphasized.

球面屈折レンズ8においても、第1の実施例と同様な液面によるレンズ形成プロセスを用いることで、図7の水平方向と図8の垂直方向との両方に同時に遮光体3との高い位置精度を維持して簡単に形成することができる。   Also in the spherical refraction lens 8, by using the same lens forming process with the liquid surface as in the first embodiment, high positional accuracy of the light shielding body 3 in both the horizontal direction in FIG. 7 and the vertical direction in FIG. And can be formed easily.

さらに、上下視野角拡大における遮光体3の構成は、一松模様などでもよく格子型に制限されるものではない。   Furthermore, the configuration of the light shielding body 3 in the vertical viewing angle expansion may be a monochromatic pattern, and is not limited to the lattice type.

以上のような球面屈折レンズ8の構造及びその製造プロセスにより、左右方向と上下方向との両方に遮光体3を配列した上下視野角拡大構成においても、左右方向と上下方向の両方に球面屈折レンズ8を高精度で容易に形成することができ、水平方向と上下方向の両方で3つの輝度ピークの解消と視野角の裾野の広い連続的で滑らかな輝度特性が得られる。   Due to the structure of the spherical refraction lens 8 and the manufacturing process thereof as described above, the spherical refraction lens can be provided in both the horizontal direction and the vertical direction even in the vertical viewing angle expansion configuration in which the light shields 3 are arranged in both the horizontal direction and the vertical direction. 8 can be easily formed with high accuracy, and a continuous and smooth luminance characteristic with a wide viewing angle can be obtained by eliminating three luminance peaks in both the horizontal and vertical directions.

また、本発明による光拡散シート1は、光入射側基板の表面が平坦となっているため、光拡散シート1の面が平坦な反射型フレネルレンズシートに、粘着剤などで密着して張り合わせることが可能である。このような構成にすることで、フレネルレンズシートと光拡散シート1との隙間の発生がなく、安定した品質の映像を提供することができることから、本発明は、反射型フレネルレンズシートとの組み合わせに極めて有効に作用する。従来、光入射側の表面に屈折レンズの凹凸が形成された光拡散レンズでは、フレネルレンズシートの間に空気層が必要なため接合できず、温度変化による互いの反り量の違いから隙間が発生するなどの問題を有していた。   In addition, since the light diffusing sheet 1 according to the present invention has a flat surface on the light incident side substrate, the light diffusing sheet 1 has a flat surface and is adhered to a reflective Fresnel lens sheet with an adhesive or the like. It is possible. By adopting such a configuration, since there is no gap between the Fresnel lens sheet and the light diffusion sheet 1 and a stable quality image can be provided, the present invention is combined with a reflective Fresnel lens sheet. It works extremely effectively. Conventionally, a light diffusion lens with concave and convex surfaces formed on the surface on the light incident side cannot be joined because an air layer is required between the Fresnel lens sheets, and a gap occurs due to the difference in the amount of warpage due to temperature changes. Had problems such as.

本実施例では、格子状に遮光体3が配列された上下視野角タイプの透過型スクリーンの光拡散シートを示す。遮光体3の断面が、略三角形状をしており、遮光体3のピッチが90μm、底部幅60μm、高さが90μm、遮光体3の開口部6の幅が30μmとなる形状を遮光体3の設計値とし、実施を行った。   In the present embodiment, a light diffusion sheet of a transmission screen of a vertical viewing angle type in which light shielding bodies 3 are arranged in a lattice shape is shown. The cross section of the light shield 3 has a substantially triangular shape, and the light shield 3 has a shape in which the pitch of the light shield 3 is 90 μm, the bottom width is 60 μm, the height is 90 μm, and the width of the opening 6 of the light shield 3 is 30 μm. The design value was set as follows.

まず、粒子径10μm以下で体積比率約5%の樹脂ビーズを混合させたアクリル系樹脂を基材とする光出射側基板2に、体積比率9%のカーボン微粒子を含有した2液混合ウレタン系樹脂を基材とする黒色液状樹脂を塗布する。   First, a two-component mixed urethane resin containing carbon fine particles with a volume ratio of 9% on a light emission side substrate 2 based on an acrylic resin mixed with resin beads having a particle diameter of 10 μm or less and a volume ratio of about 5%. A black liquid resin having a base material is applied.

次に、遮光体3の断面三角形状溝が水平方向と垂直方向とに加工された遮光体3の転写金型を用いて、硬化前の黒色液状樹脂上に押し当て、上部より加圧した状態で黒色液状樹脂を光射出側基板2の上で硬化させて、格子状の遮光体3を形成した。   Next, using the transfer mold of the light shielding body 3 in which the cross-sectional triangular grooves of the light shielding body 3 are processed in the horizontal direction and the vertical direction, the pressure is applied from above to the black liquid resin before curing. Then, the black liquid resin was cured on the light emitting side substrate 2 to form a lattice-shaped light blocking body 3.

ここで、光出射側基板2の厚みは2mm、遮光体3の水平と垂直のピッチは各55μmと80μmとし、遮光体3の断面三角形状の傾斜面θの平均角度は80°(ここで、反射レンズ7の反射光が全て開口部6を通過するよう遮光体3の斜面は、曲面形状とした)とした。   Here, the thickness of the light emitting side substrate 2 is 2 mm, the horizontal and vertical pitches of the light shielding body 3 are 55 μm and 80 μm, respectively, and the average angle of the inclined surface θ having a triangular cross section of the light shielding body 3 is 80 ° (here, The slant surface of the light shield 3 is curved so that all the reflected light from the reflection lens 7 passes through the opening 6).

次に、作製された遮光体3の上面から、レンズ樹脂層4となる低屈折率透明硬化性樹脂を塗布する。今回は、低屈折率の透明紫外線硬化樹脂にエポテック社のOG134を用いた。   Next, a low refractive index transparent curable resin to be the lens resin layer 4 is applied from the upper surface of the manufactured light shield 3. This time, OG134 of Epotec Co. was used as a transparent UV curable resin having a low refractive index.

この低屈折率の透明紫外線硬化樹脂を遮光体3の凹凸面に、スプレー法にて定量塗布を行った後、紫外線硬化を行った。   This low refractive index transparent ultraviolet curable resin was quantitatively applied to the uneven surface of the light shielding body 3 by a spray method, followed by ultraviolet curing.

スプレー塗布前に、塗布液体との濡れ性を上げるために遮光体3の表面をオゾン処理した。スプレー塗布した直後に、遮光体3の傾斜面へ塗布液体の薄膜が形成されると共に、開口部6には凹状のメニスカスにより球面屈折レンズ8が形成される。   Prior to spray application, the surface of the light-shielding body 3 was subjected to ozone treatment in order to improve wettability with the application liquid. Immediately after spray coating, a thin film of coating liquid is formed on the inclined surface of the light shield 3, and a spherical refractive lens 8 is formed in the opening 6 by a concave meniscus.

次に、光入射側樹脂層5となる高屈折率の透明紫外線硬化性樹脂を、遮光体3の頂点からの膜厚が100μmになるように、スプレー法にて塗布した。   Next, a transparent UV curable resin with a high refractive index to be the light incident side resin layer 5 was applied by a spray method so that the film thickness from the top of the light shield 3 was 100 μm.

高屈折率の透明紫外線硬化樹脂にはノーランド社のNOA―60を用いた。塗布の後、紫外線硬化を行い光拡散スクリーン1を完成した。   Noland NOA-60 was used as the transparent UV curable resin having a high refractive index. After coating, UV curing was performed to complete the light diffusion screen 1.

両スクリーンを、濁度計(日本電色工業社製 NDH2000)を用いて全光線透過率の測定を行い評価した。   Both screens were evaluated by measuring the total light transmittance using a turbidimeter (NDH2000 manufactured by Nippon Denshoku Industries Co., Ltd.).

その結果、視野角0°をピークとする滑らかな視野角特性が得られた。また、水平方向のβ角(1/3ピーク輝度の視野角)が37°、垂直方向のβ角が18°と水平及び上下とも広い視野角が得られた。   As a result, a smooth viewing angle characteristic having a peak viewing angle of 0 ° was obtained. Further, a wide β and a vertical viewing angle were obtained with a horizontal β angle (viewing angle of 1/3 peak luminance) of 37 ° and a vertical β angle of 18 °.

以上により作製された光拡散スクリーンを取り付けた透過型スクリーンを作製し、背面投射型ディスプレイを作製したところ、輝度ムラの無い高視野角で良好な背面投射型ディスプレイが得られた。   A transmissive screen with the light diffusing screen produced as described above was produced, and a rear projection display was produced. As a result, a good rear projection display with a high viewing angle without uneven brightness was obtained.

本発明にかかる透過型スクリーン用の拡散シートは、簡単の製造工程で反射レンズと球面屈折レンズを高いアライメント精度で形成することで、全反射型光拡散シートに強く現れる3つの輝度ピークによる凹凸を解消して、広い視野角有し、背面投射型ディスプレイ等として有用である   The diffusing sheet for a transmissive screen according to the present invention forms the reflection lens and the spherical refraction lens with high alignment accuracy by a simple manufacturing process, so that unevenness due to three luminance peaks that strongly appear in the total reflection type light diffusing sheet is formed. Eliminates and has a wide viewing angle and is useful as a rear projection display

本発明の第1の実施例における光拡散シートの断面を模式的に示す図The figure which shows typically the cross section of the light-diffusion sheet | seat in 1st Example of this invention. 本発明の第1の実施例における光拡散シートの球面屈折レンズを説明するための図The figure for demonstrating the spherical refraction lens of the light-diffusion sheet | seat in 1st Example of this invention. 本発明の第1の実施例における光拡散シートの動作説明図Operation explanatory diagram of the light diffusion sheet in the first embodiment of the present invention 本発明の第1の実施例における光拡散シートの反射レンズの動作説明図Operation explanatory diagram of the reflection lens of the light diffusion sheet in the first embodiment of the present invention 本発明の第1の実施例における光拡散シートの視野角特性を示す図The figure which shows the viewing angle characteristic of the light-diffusion sheet | seat in 1st Example of this invention 本発明の第2の実施例における光拡散シートの上面図The top view of the light-diffusion sheet in 2nd Example of this invention 図6に示す本発明の光拡散シートのA−A’断面図A-A 'sectional view of the light diffusion sheet of the present invention shown in FIG. 図6に示す本は光拡散シートのB−B’断面図The book shown in FIG. 6 is a B-B ′ sectional view of the light diffusion sheet. 背面投射型ディスプレイの構造を模式的に示す図The figure which shows the structure of the rear projection type display typically 透過型スクリーンの構造を模式的に示す図Diagram showing the structure of a transmission screen 従来の反射型光拡散シートの立体構造を概略的に示す図The figure which shows the three-dimensional structure of the conventional reflection type light-diffusion sheet roughly 従来の反射型光拡散シートの動作説明図Operation explanatory diagram of conventional reflection type light diffusion sheet 従来の反射型光拡散シートの視野角特性を示す図The figure which shows the viewing angle characteristic of the conventional reflection type light diffusion sheet 第1の従来例の光拡散シートの断面を模式的に示す図The figure which shows typically the cross section of the light diffusion sheet of a 1st prior art example

符号の説明Explanation of symbols

1 光拡散シート
2 光出射側基板
3 遮光体
4 レンズ樹脂層
5 光入射側樹脂層
6 開口部
7 反射レンズ
8 球面屈折レンズ
9 平行光
10 背面投射型ディスプレイ
11 光学エンジン
12 投射レンズ
13 ミラー
14 画像光
15 透過型スクリーン
16 キャビネット
17 フレネルレンズシート
18 高屈折率透明樹脂層
DESCRIPTION OF SYMBOLS 1 Light diffusing sheet 2 Light emission side board | substrate 3 Light-shielding body 4 Lens resin layer 5 Light incident side resin layer 6 Aperture 7 Reflective lens 8 Spherical refractive lens 9 Parallel light 10 Rear projection display 11 Optical engine 12 Projection lens 13 Mirror 14 Image Light 15 Transmission type screen 16 Cabinet 17 Fresnel lens sheet 18 High refractive index transparent resin layer

Claims (11)

透明基板の光出射側基板と、
前記光出射側基板の一方の面に光透過部となる開口部を介在して配列される断面三角形状の遮光体と、
断面三角形状の前記遮光体の傾斜面に設けられる第1の屈折率の透明樹脂層で形成される反射レンズと、
隣接する前記遮光体の開口部に形成される当該第1の屈折率の透明樹脂層の球面屈折レンズと、
前記反射レンズと前記球面屈折レンズを覆って前記第1の屈折率よりも高い第2の屈折率の透明樹脂層で形成される光入射側樹脂層と
を備えた透過型スクリーン用光拡散シート。
A light emission side substrate of a transparent substrate;
A light shielding body having a triangular cross section arranged on one surface of the light emitting side substrate with an opening serving as a light transmitting portion interposed therebetween;
A reflective lens formed of a transparent resin layer having a first refractive index provided on an inclined surface of the light shielding body having a triangular cross section;
A spherical refractive lens of the transparent resin layer of the first refractive index formed in the opening of the adjacent light shield;
A light diffusing sheet for a transmission type screen, comprising: a light incident side resin layer formed of a transparent resin layer having a second refractive index higher than the first refractive index, covering the reflective lens and the spherical refractive lens.
前記球面屈折レンズが、隣接する断面三角形状の前記遮光体の開口部に前記第1の屈折率の透明樹脂材料を光入射側に凹面を有して形成されることを特徴とする請求項1に記載の光透過型スクリーン用光拡散シート。 2. The spherical refractive lens is formed by forming a transparent resin material having the first refractive index in an opening portion of the light shielding body having a triangular cross section adjacent thereto and having a concave surface on the light incident side. A light diffusing sheet for light transmissive screens as described in 1. 第2の屈折率の前記光入射樹脂層の平坦表面に垂直に入射する平行光と前記遮光体の傾斜面の法線との成す角度が、第1の屈折率のレンズ樹脂層の材料と第2の屈折率の前記光入射樹脂層との材料の屈折率で決定される全反射角度である臨界角より大きいことを特徴とする請求項2に記載の透過型スクリーン用光拡散シート。 The angle formed between the parallel light perpendicularly incident on the flat surface of the light incident resin layer having the second refractive index and the normal line of the inclined surface of the light shielding body is determined by the material of the lens resin layer having the first refractive index and the first refractive index. 3. The light diffusing sheet for a transmissive screen according to claim 2, wherein the light diffusing sheet has a refractive index greater than a critical angle which is a total reflection angle determined by a refractive index of the material with the light incident resin layer having a refractive index of 2. 第1の屈折率の透明樹脂層で形成されるレンズ樹脂層を形成する際に、前記遮光体の表面の臨界表面張力より小さい表面張力を示す低屈折率樹脂材料液体を用いることを特徴とする請求項1に記載の透過型スクリーン用光拡散シート。 When forming a lens resin layer formed of a transparent resin layer having a first refractive index, a low refractive index resin material liquid exhibiting a surface tension smaller than the critical surface tension of the surface of the light shielding body is used. The light diffusing sheet for transmissive screen according to claim 1. 第1の屈折率の透明樹脂層で形成されるレンズ樹脂層の形成の際に、前記遮光体の表面及び開口部の表面に低屈折率樹脂材料液体を塗布する前、前記遮光体の表面及び開口部の表面をオゾンアッシング処理することを特徴とする請求項1に記載の透過型スクリーン用光拡散シート。 During the formation of the lens resin layer formed of the transparent resin layer having the first refractive index, before applying the low refractive index resin material liquid to the surface of the light shielding body and the surface of the opening, the surface of the light shielding body and The light diffusing sheet for a transmissive screen according to claim 1, wherein the surface of the opening is subjected to ozone ashing. 前記光出射側基板に、拡散粒子が含有して形成されていることを特徴とする請求項1に記載の透過型スクリーン用光拡散シート。 The light diffusing sheet for a transmissive screen according to claim 1, wherein the light emitting side substrate is formed to contain diffusing particles. 透明基板の光出射側基板の一方の面に光透過部となる開口部を介在して配列される断面三角形状の遮光体を形成する第1の工程と、
断面三角形状の前記遮光体の傾斜面に設けられる第1の屈折率の透明樹脂層で反射レンズを形成するとともに、隣接する前記遮光体の開口部に当該第1の屈折率の透明樹脂層の球面屈折レンズを形成する第2の工程と、
前記第2の工程後、前記反射レンズと前記球面屈折レンズを覆って前記第1の屈折率よりも高い第2の屈折率の透明樹脂層で光入射側樹脂層を形成する第3の工程と
を備える透過型スクリーン用光拡散シートの製造方法。
A first step of forming a light-shielding body having a triangular cross section arranged on one surface of the light emitting side substrate of the transparent substrate with an opening serving as a light transmitting portion interposed therebetween;
A reflective lens is formed of a transparent resin layer having a first refractive index provided on the inclined surface of the light shielding body having a triangular cross section, and the transparent resin layer having the first refractive index is formed in an opening of the adjacent light shielding body. A second step of forming a spherical refractive lens;
A third step of forming a light incident side resin layer with a transparent resin layer having a second refractive index higher than the first refractive index, covering the reflective lens and the spherical refractive lens after the second step; A method for producing a light diffusing sheet for a transmissive screen comprising:
前記第2の工程において、前記遮光体の表面の臨界表面張力より小さい表面張力を示す低屈折率樹脂材料液体を用いることを特徴とする請求項7に記載の透過型スクリーン用光拡散シートの製造方法。 8. The light diffusing sheet for a transmissive screen according to claim 7, wherein in the second step, a low refractive index resin material liquid having a surface tension smaller than a critical surface tension of the surface of the light shielding body is used. Method. 前記第2の工程において、前記遮光体の表面及び開口部の表面に低屈折率樹脂材料液体を塗布する前、前記遮光体の表面及び開口部の表面をオゾンアッシング処理することを特徴とする請求項7に記載の透過型スクリーン用光拡散シートの製造方法。 In the second step, the surface of the light shielding body and the surface of the opening are subjected to ozone ashing before applying the low refractive index resin material liquid to the surface of the light shielding body and the surface of the opening. Item 8. A method for producing a light diffusing sheet for a transmissive screen according to Item 7. 第2の屈折率の前記光入射樹脂層表面に垂直に入射する平行光と前記遮光体の傾斜面の法線との成す角度が、第1の屈折率のレンズ樹脂層の材料と第2の屈折率の前記光入射樹脂層との材料の屈折率で決定される全反射角度である臨界角より大きいことを特徴とする請求項7に記載の透過型スクリーン用光拡散シートの製造方法。 The angle formed between the parallel light perpendicularly incident on the surface of the light incident resin layer having the second refractive index and the normal line of the inclined surface of the light shielding body is determined by the material of the lens resin layer having the first refractive index and the second refractive index. The method for producing a light diffusing sheet for a transmission type screen according to claim 7, wherein the light diffusion sheet has a refractive index larger than a critical angle which is a total reflection angle determined by a refractive index of a material with the light incident resin layer. 透明基板の光出射側基板と、
前記光出射側基板の一方の面に光透過部となる開口部を介在して配列される断面三角形状の遮光体と、
隣接する前記遮光体の開口部に形成される第1の屈折率の透明樹脂層の球面屈折レンズと、
前記遮光体と前記球面屈折レンズを覆って前記第1の屈折率よりも高い第2の屈折率の透明樹脂層で形成される光入射側樹脂層と
を備え、
前記遮光体が前記第2の屈折率の透明樹脂層より低い第3の屈折率の樹脂材料で形成され、前記遮光体の傾斜面が反射レンズとなる、
ことを特徴とする透過型スクリーン用光拡散シート。
A light emission side substrate of a transparent substrate;
A light shielding body having a triangular cross section arranged on one surface of the light emitting side substrate with an opening serving as a light transmitting portion interposed therebetween;
A spherical refractive lens of a transparent resin layer having a first refractive index formed in an opening of the adjacent light shield;
A light incident side resin layer formed of a transparent resin layer having a second refractive index higher than the first refractive index covering the light shielding body and the spherical refractive lens;
The light shielding body is formed of a resin material having a third refractive index lower than that of the transparent resin layer having the second refractive index, and the inclined surface of the light shielding body serves as a reflection lens;
A light diffusing sheet for a transmissive screen characterized by the above.
JP2007053803A 2006-03-09 2007-03-05 Light diffusion sheet for transmission type screen, and a method for manufacturing light diffusion sheet Pending JP2007272209A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2007053803A JP2007272209A (en) 2006-03-09 2007-03-05 Light diffusion sheet for transmission type screen, and a method for manufacturing light diffusion sheet

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2006063881 2006-03-09
JP2007053803A JP2007272209A (en) 2006-03-09 2007-03-05 Light diffusion sheet for transmission type screen, and a method for manufacturing light diffusion sheet

Publications (1)

Publication Number Publication Date
JP2007272209A true JP2007272209A (en) 2007-10-18

Family

ID=38675009

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2007053803A Pending JP2007272209A (en) 2006-03-09 2007-03-05 Light diffusion sheet for transmission type screen, and a method for manufacturing light diffusion sheet

Country Status (1)

Country Link
JP (1) JP2007272209A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2018124315A (en) * 2017-01-30 2018-08-09 大日本印刷株式会社 Screen and video display device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2018124315A (en) * 2017-01-30 2018-08-09 大日本印刷株式会社 Screen and video display device

Similar Documents

Publication Publication Date Title
KR100918713B1 (en) Double-sided lens sheet and projection screen
KR100993232B1 (en) Method for manufacturing optical element, optical element, illuminating optical apparatus, display apparatus, and electronic apparatus
US6970288B2 (en) Micro-lens sheet and projection screen
KR20040014358A (en) Fresnel lens sheet and rear projection screen including the same
JP2007058030A (en) Fresnel lens sheet, transmission screen and rear projection type display device
JP5003298B2 (en) Optical sheet, backlight unit using the same, and display device
JP6806911B2 (en) Backlight unit and liquid crystal display
JP2008310251A (en) Optical sheet, back light unit, and display apparatus
JP2004110002A (en) Diffusing sheet for transparent screen and transparent screen
JP4235483B2 (en) Diffusion sheet, diffusion sheet mold, transmission screen, and diffusion sheet manufacturing method
JPH11102024A (en) Transmission screen
JP2009063849A (en) Optical diffusion screen and method of manufacturing the same, and rear projection display apparatus
JP2007272209A (en) Light diffusion sheet for transmission type screen, and a method for manufacturing light diffusion sheet
JP2010135220A (en) Surafce light source element and image display device using the same
JP2007293166A (en) Light diffusion sheet for transmission type screen, and transmission type screen
TW200304579A (en) Micro-lens sheet and projection screen
JP2006065185A (en) Transmission type screen and manufacturing method thereof, and back projection type display device
JP2005215417A (en) Microlens array
TWI323818B (en) Liquid crystal display lighting apparatus
JP2005004059A (en) Transmission type screen and back projection type display device
JP2009063848A (en) Optical diffusion screen and method of manufacturing the same, and rear projection display apparatus
JP2008287269A (en) Microlens sheet and display using the same
JP2000171905A (en) Transmission type screen
JP2008282026A (en) Microlens sheet and display using the same
JP2000098497A (en) Transmission type screen and back projection type display device using the same