JP2010107828A

JP2010107828A - Projection type display apparatus

Info

Publication number: JP2010107828A
Application number: JP2008281186A
Authority: JP
Inventors: Kuniko Kojima; 邦子小島; Jun Kondo; 潤近藤; Tomohiro Sasagawa; 智広笹川
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2008-10-31
Filing date: 2008-10-31
Publication date: 2010-05-13

Abstract

PROBLEM TO BE SOLVED: To obtain a projection type display apparatus that improves the uniformity of illumination distribution despite a small configuration even in an optical system using a multi-primary color light source. SOLUTION: The projection type display apparatus includes: a light source 4; and a light intensity uniformizing element that uniformizes the intensity distribution of a luminous flux emitted from the light source 4. The apparatus projects and displays an image by using the luminous flux emitted from the light intensity uniformizing element. In the projection type display apparatus, the light intensity uniformizing element 6 is configured such that light intensity uniformizing sections 61 and 62 used for uniformizing the intensity distribution of the luminous flux are joined in the direction of an optical axis. The light intensity uniformizing sections 61 and 62 are used which are different in type so that the uniformizing characteristics of the intensity distribution of the luminous flux may change on the joint face of the light intensity uniformizing sections 61 and 62. COPYRIGHT: (C)2010,JPO&INPIT

Description

本発明は、スクリーン上に画像を投写表示する投写型表示装置に関するものである。 The present invention relates to a projection display device that projects and displays an image on a screen.

投写型表示装置では、スクリーン上に均一な光強度の明るい画像を表示することが望まれている。このため、光源から発生した光束を、光強度（照度分布）の均一性を保ちつつ、効率良くスクリーンまで導く必要がある。このため、従来の投写型表示装置は、ライトパイプ（筒状光学素子）を用いて光源からの光束をライトバルブまで導いていた。 In a projection display device, it is desired to display a bright image with uniform light intensity on a screen. For this reason, it is necessary to efficiently guide the light beam generated from the light source to the screen while maintaining the uniformity of the light intensity (illuminance distribution). For this reason, the conventional projection display apparatus has used the light pipe (cylindrical optical element) to guide the light flux from the light source to the light valve.

例えば、特許文献１に記載の投写型表示装置は、入射口側に断面積が連続的に減少するように形成されたテーパー部と、出射口側に断面形状が一定になるように形成された平行部と、を有したライトトンネル（ライトパイプ）を備えている。このようなライトパイプは、その長さによって光強度の均一性が決まる。このため、投写型表示装置を作製する場合には、投写型表示装置に必要な光強度均一性に基づいて、ライトパイプの長さが決定される。 For example, the projection display device described in Patent Document 1 is formed with a tapered portion formed so that a cross-sectional area continuously decreases on the incident port side and a cross-sectional shape constant on the output port side. And a light tunnel having a parallel portion. In such a light pipe, the light intensity uniformity is determined by its length. For this reason, when producing a projection display device, the length of the light pipe is determined based on the light intensity uniformity required for the projection display device.

ところで、投写型表示装置では、寿命が長くメンテナンス作業が不要となり、かつ色再現範囲を広くすることができるという利点を有するという理由から、レーザ光源やＬＥＤ光源のような多原色の光源を採用する光学系が提案されている。このような多原色の光源を採用した場合、光束を十分に混色させるためには、ライトパイプでの光強度の均一化が要求される。 By the way, the projection display device employs a multi-primary color light source such as a laser light source or an LED light source because it has an advantage that it has a long life and does not require maintenance work and can widen a color reproduction range. Optical systems have been proposed. When such a multi-primary light source is employed, it is required to make the light intensity uniform in the light pipe in order to sufficiently mix the luminous flux.

特開２００４−２５２１１２号公報（段落００３４、図２）Japanese Patent Laying-Open No. 2004-252112 (paragraph 0034, FIG. 2)

しかしながら、上記従来の技術では、テーパー部を設けても、光強度均一化の効果についてはほとんど変わらないので、ライトパイプを長くしなければ光強度を均一化できない。そして、ライトパイプを長くすると、投写型表示装置の構成が大きくなるとともにレイアウトに大きな影響を与え、さらにコスト高になるという問題点があった。 However, in the conventional technique, even if the tapered portion is provided, the effect of uniforming the light intensity is hardly changed. Therefore, the light intensity cannot be uniformed unless the light pipe is lengthened. When the light pipe is lengthened, the configuration of the projection display device is increased, and the layout is greatly affected, which further increases the cost.

本発明は、上記に鑑みてなされたものであって、多原色の光源を採用した光学系においても、小さな構成で照度分布の均一性を向上させることができる投写型表示装置を提供することを目的とする。 The present invention has been made in view of the above, and provides a projection display device that can improve the uniformity of illuminance distribution with a small configuration even in an optical system employing a multi-primary light source. Objective.

上述した課題を解決し、目的を達成するために、本発明は、光源と、前記光源から出射された光束の強度分布を均一化する光強度均一化素子と、を有するとともに、前記光強度均一化素子から出射された光束を用いて画像の投写表示を行う投写型表示装置において、前記光強度均一化素子は、複数の前記強度分布を均一化する光強度均一化部から構成されていることを特徴とする。 In order to solve the above-described problems and achieve the object, the present invention includes a light source and a light intensity uniformizing element that uniformizes an intensity distribution of a light beam emitted from the light source, and the light intensity is uniform. In a projection display apparatus that performs projection display of an image using a light beam emitted from the conversion element, the light intensity uniformizing element includes a plurality of light intensity uniformizing sections that uniformize the intensity distribution. It is characterized by.

この発明によれば、光強度均一化素子を複数の光強度均一化部で構成しているので、多原色の光源を採用した光学系においても、小さな構成で照度分布の均一性を向上させることが可能になるという効果を奏する。 According to the present invention, since the light intensity uniformizing element is composed of a plurality of light intensity uniformizing sections, the uniformity of the illuminance distribution can be improved with a small structure even in an optical system employing a multi-primary color light source. There is an effect that becomes possible.

以下に、本発明に係る投写型表示装置の実施の形態を図面に基づいて詳細に説明する。なお、この実施の形態によりこの発明が限定されるものではない。 Embodiments of a projection display device according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

実施の形態
図１は、本発明の実施の形態に係る投写型表示装置の光学系の概略構成を示す図である。投写型表示装置１は、ライトバルブを用いてスクリーン上に画像を投写する投写型の画像表示装置である。 Embodiment FIG. 1 is a diagram showing a schematic configuration of an optical system of a projection display apparatus according to an embodiment of the present invention. The projection display device 1 is a projection image display device that projects an image on a screen using a light valve.

投写型表示装置１は、光源４と、光強度均一化素子６と、照明光学系７と、反射型ライトバルブ（反射型光変調素子）２と、照明光学系７により照明された反射型ライトバルブ２の被照明面（画像形成領域）２ｂの画像をスクリーン（図示せず）に投写する投写光学系３とを有している。 The projection display device 1 includes a light source 4, a light intensity uniformizing element 6, an illumination optical system 7, a reflective light valve (reflective light modulation element) 2, and a reflective light illuminated by the illumination optical system 7. And a projection optical system 3 that projects an image of an illuminated surface (image forming region) 2b of the bulb 2 onto a screen (not shown).

光源４は、複数色（図１においては３色）のレーザ光源４１と、レーザ光源４１から出射された光束を１〜複数枚のレンズまたはミラーで集光する複数（図１においては３枚）の集光光学系４２と、集光光学系４２から出射された光束を光強度均一化素子６に導く複数本（図１においては３本）の光ファイバ４３とから構成されている。 The light source 4 includes a laser light source 41 of a plurality of colors (three colors in FIG. 1) and a plurality (three in FIG. 1) that collects light beams emitted from the laser light source 41 with one to a plurality of lenses or mirrors. The condensing optical system 42 and a plurality (three in FIG. 1) of optical fibers 43 that guide the light beam emitted from the condensing optical system 42 to the light intensity uniformizing element 6.

光源４では、１つのレーザ光源４１に、１つの集光光学系４２と１本の光ファイバ４３を対応させている。したがって、各レーザ光源４１から出射された光束は、それぞれのレーザ光源４１に対応する集光光学系４２と光ファイバ４３を介して光強度均一化素子６に導かれる。 In the light source 4, one condensing optical system 42 and one optical fiber 43 correspond to one laser light source 41. Therefore, the light beam emitted from each laser light source 41 is guided to the light intensity uniformizing element 6 through the condensing optical system 42 and the optical fiber 43 corresponding to each laser light source 41.

照明光学系７は、レンズ７１，７２と、第１ミラー７３と、第２ミラー７４とを含んで構成されている。なお、図１では照明光学系７を２枚のレンズおよび２枚のミラーで構成した場合を示したが、レンズやミラーの枚数は２枚に限定されるものではなく何枚であってもよい。照明光学系７は、レンズ７１，７２、第１ミラー７３、第２ミラー７４によって、光強度均一化素子６から出射した光束を反射型ライトバルブ２に導いている。 The illumination optical system 7 includes lenses 71 and 72, a first mirror 73, and a second mirror 74. Although FIG. 1 shows the case where the illumination optical system 7 is composed of two lenses and two mirrors, the number of lenses and mirrors is not limited to two and may be any number. . The illumination optical system 7 guides the light beam emitted from the light intensity uniformizing element 6 to the reflective light valve 2 by lenses 71 and 72, a first mirror 73, and a second mirror 74.

光強度均一化素子６は、光源４が出射した光束の光強度および色ムラを均一化する（照度ムラおよび色ムラを低減する）機能を有している。光強度均一化素子６は、種類の異なる光強度均一化部６１と光強度均一化部６２から構成されており、光強度均一化部６１，６２が一体化されて形成されている。光強度均一化部６１は、光の入射口である入射面（入射端面）６１ａが光ファイバ４３側を向き、光の出射口である出射面（出射端面）６１ｂが光強度均一化部６２を向くよう光強度均一化素子６内に配設されている。また、光強度均一化部６２は、光の入射口である入射面６２ａが光強度均一化部６１側を向き、光の出射口である出射面６２ｂが照明光学系７を向くよう光強度均一化素子６内に配設されている。入射面６１ａ、出射面６１ｂ、入射面６２ａ、出射面６２ｂは、それぞれ光軸１ａと垂直な面である。 The light intensity uniformizing element 6 has a function of making the light intensity and color unevenness of the light beam emitted from the light source 4 uniform (reducing illumination unevenness and color unevenness). The light intensity uniformizing element 6 includes a light intensity uniformizing section 61 and a light intensity uniformizing section 62 of different types, and the light intensity uniformizing sections 61 and 62 are integrally formed. In the light intensity uniformizing unit 61, an incident surface (incident end surface) 61a that is an incident port of light faces the optical fiber 43 side, and an outgoing surface (exit end surface) 61b that is an outgoing port of light is an optical intensity uniformizing unit 62. The light intensity uniformizing element 6 is disposed so as to face. Further, the light intensity uniformizing unit 62 has a uniform light intensity such that the incident surface 62a that is the light incident port faces the light intensity uniformizing unit 61 side, and the emission surface 62b that is the light emission port faces the illumination optical system 7. Arranged in the activating element 6. The entrance surface 61a, the exit surface 61b, the entrance surface 62a, and the exit surface 62b are surfaces perpendicular to the optical axis 1a.

光強度均一化部６１，６２は、例えばガラス又は樹脂等の透明材料で作られた素子である。光強度均一化部６１は、側壁内側が全反射面となるように構成された多角形柱状のロッド（断面形状が多角形の柱状部材）、または光反射面を内側にして筒状に組み合わされた断面形状が多角形のライトパイプ（管状部材）などを含んで構成されている。光強度均一化部６１，６２は、光強度均一化部６１、６２が多角柱状のロッドである場合には、透明材料と空気界面との全反射作用を利用して光を複数回反射させた後に出射端（出射面６１ｂ，６２ｂ）から光を出射させる。また、光強度均一化部６１，６２は、光強度均一化部６１、６２が多角形のライトパイプである場合には、内側を向く表面鏡の反射作用を利用して光を複数回反射させた後に出射面６１ｂ，６２ｂから光を出射させる。 The light intensity uniformizing portions 61 and 62 are elements made of a transparent material such as glass or resin. The light intensity uniformizing unit 61 is a polygonal columnar rod (a columnar member having a polygonal cross-section) configured such that the inner side of the side wall becomes a total reflection surface, or is combined in a cylindrical shape with the light reflection surface inside. The cross-sectional shape includes a polygonal light pipe (tubular member) and the like. When the light intensity uniformizing sections 61 and 62 are polygonal rods, the light intensity uniformizing sections 61 and 62 reflect light multiple times using the total reflection action between the transparent material and the air interface. Later, light is emitted from the emission ends (emission surfaces 61b and 62b). Further, when the light intensity equalizing units 61 and 62 are polygonal light pipes, the light intensity equalizing units 61 and 62 reflect light a plurality of times by using the reflecting action of the surface mirror facing inward. After that, light is emitted from the emission surfaces 61b and 62b.

光強度均一化素子６は、光束の進行方向に適当な長さを確保すれば、内部で複数回反射した光が光強度均一化素子６の出射面６２ｂの近傍に重畳照射され、これにより光強度均一化素子６の出射面６２ｂの近傍で略均一な強度分布が得られる。この略均一な強度分布を有する出射面６２ｂからの出射光は、照明光学系７によって反射型ライトバルブ２へと導かれ、反射型ライトバルブ２の被照明面２ｂを照明する。 If the light intensity uniformizing element 6 secures an appropriate length in the traveling direction of the light beam, the light reflected therein a plurality of times is superimposed and irradiated in the vicinity of the exit surface 62b of the light intensity uniformizing element 6 so that the light A substantially uniform intensity distribution is obtained in the vicinity of the emission surface 62b of the intensity uniformizing element 6. The outgoing light from the outgoing surface 62b having a substantially uniform intensity distribution is guided to the reflective light valve 2 by the illumination optical system 7, and illuminates the illuminated surface 2b of the reflective light valve 2.

反射型ライトバルブ２は、照明光学系７からの入射光束を投写光学系３に向けて反射（光軸２ａ方向に反射）する素子であり、投写光学系３は、反射型ライトバルブ２が反射した光束（画像）をスクリーン上に画像投写する。 The reflective light valve 2 is an element that reflects an incident light beam from the illumination optical system 7 toward the projection optical system 3 (reflects in the direction of the optical axis 2a). The projection optical system 3 is reflected by the reflective light valve 2. The projected light beam (image) is projected onto the screen.

つぎに、照明光学系７内の光路における光伝播について説明する。図２は、照明光学系内の光伝播を説明するための図である。図２では、照明光学系７の作用、光強度均一化素子６と反射型ライトバルブ２の関係を概念的に示している。 Next, light propagation in the optical path within the illumination optical system 7 will be described. FIG. 2 is a diagram for explaining light propagation in the illumination optical system. FIG. 2 conceptually shows the operation of the illumination optical system 7 and the relationship between the light intensity uniformizing element 6 and the reflective light valve 2.

本実施の形態においては、照明光学系７は光強度均一化部６２の出射面６２ｂと反射型ライトバルブ２の被照明面２ｂとが光学的に共役な関係となるよう構成されている。換言すると、複数の光強度均一化部のうち最も照明光学系７側に配置された光強度均一化部６２の出射面６２ｂの断面形状を、反射型ライトバルブ２の被照明面２ｂの形状と略相似形に形成しておく。反射型ライトバルブ２は、例えばＤＭＤ（ディジタル・マイクロミラー・デバイス）（登録商標）素子などの反射型の光変調素子、反射型液晶表示素子あるいは透過型液晶表示素子等である。本実施の形態では、反射型ライトバルブ２が、ＤＭＤ（登録商標）素子である場合について説明する。 In the present embodiment, the illumination optical system 7 is configured such that the exit surface 62b of the light intensity uniformizing unit 62 and the illuminated surface 2b of the reflective light valve 2 are in an optically conjugate relationship. In other words, the cross-sectional shape of the exit surface 62b of the light intensity uniformizing unit 62 arranged closest to the illumination optical system 7 among the plurality of light intensity uniformizing units is defined as the shape of the illuminated surface 2b of the reflective light valve 2. It is formed in a substantially similar shape. The reflection type light valve 2 is, for example, a reflection type light modulation element such as a DMD (digital micromirror device) (registered trademark) element, a reflection type liquid crystal display element or a transmission type liquid crystal display element. In the present embodiment, a case where the reflective light valve 2 is a DMD (registered trademark) element will be described.

例えば、光強度均一化素子６の出射面６２ｂの面積はＳ１であり、反射型ライトバルブ２の被照明面２ｂの面積はＳ２である。図２に示すように、光強度均一化素子６から出射される光束の立体角がΩ１であり、反射型ライトバルブ２の被照明面２ｂにおける入射光束の立体角がΩ２であるとすると、出射面６２ｂと被照明面２ｂのそれぞれの面積と立体角との積は一定に保たれる。すなわち、Ｓ１×Ω１＝Ｓ２×Ω２が成立する。 For example, the area of the exit surface 62b of the light intensity uniformizing element 6 is S1, and the area of the illuminated surface 2b of the reflective light valve 2 is S2. As shown in FIG. 2, when the solid angle of the light beam emitted from the light intensity uniformizing element 6 is Ω1, and the solid angle of the incident light beam on the illuminated surface 2b of the reflective light valve 2 is Ω2, the light beam is emitted. The product of the area and solid angle of each of the surface 62b and the illuminated surface 2b is kept constant. That is, S1 × Ω1 = S2 × Ω2 is established.

反射型ライトバルブ２は、各画素に対応する可動式のマイクロミラーを多数（例えば、数十万個）平面的に配列したものであり、画素情報に応じて各マイクロミラーの傾角（チルト）を変化させるように構成されている。反射型ライトバルブ２は、マイクロミラーの配列された面（マイクロミラーが形成された基板の表面）を基準面とした場合に、この基準面に対してマイクロミラーを一定の方向に所定の角度α（例えば、１２度）だけ傾けることによって、入射光束を投写光学系３に向けて反射する。投写光学系３に入射した光束はスクリーン（図示せず）上の画像投写に利用される。また、反射型ライトバルブ２は、マイクロミラーを基準面として設けられた光吸収板（図示せず）に向けて入射光束を反射する。換言すると、反射型ライトバルブ２は、基準面に対してマイクロミラーを一定の方向に所定の角度β（例えば、マイナス１２度）だけ傾けることによって、入射光束を光吸収板に向けて反射する。光吸収板に入射した光束は、スクリーン上の画像投写に利用されない。 The reflection type light valve 2 is a planar arrangement of a large number (for example, several hundred thousand) of movable micromirrors corresponding to each pixel, and the inclination angle (tilt) of each micromirror is set according to pixel information. It is configured to change. The reflection type light valve 2 has a predetermined angle α in a certain direction with respect to the reference surface when the surface on which the micromirrors are arranged (the surface of the substrate on which the micromirrors are formed) is used as the reference surface. By tilting by (for example, 12 degrees), the incident light beam is reflected toward the projection optical system 3. The light beam incident on the projection optical system 3 is used for image projection on a screen (not shown). The reflective light valve 2 reflects an incident light beam toward a light absorbing plate (not shown) provided with a micromirror as a reference surface. In other words, the reflective light valve 2 reflects the incident light beam toward the light absorbing plate by tilting the micromirror with respect to the reference plane in a certain direction by a predetermined angle β (for example, minus 12 degrees). The light beam incident on the light absorbing plate is not used for image projection on the screen.

つぎに、本実施の形態に係る光強度均一化素子６の詳細な作用について説明する。図３は、光強度均一化素子の断面図である。図３では、光強度均一化素子６を、光軸１ａ（直線）を含む平面で切断した場合の断面構成を示している。光強度均一化素子６は、光束の強度分布を均一化する光強度均一化部６１，６２が光軸１ａ方向に接合されて構成されている。また、光強度均一化部６１，６２には、光強度均一化部６１，６２の接合面で光束の強度分布の均一化特性が変化するよう種類の異なる光強度均一化部６１，６２を用いている。 Next, a detailed operation of the light intensity uniformizing element 6 according to the present embodiment will be described. FIG. 3 is a cross-sectional view of the light intensity uniformizing element. FIG. 3 shows a cross-sectional configuration when the light intensity equalizing element 6 is cut along a plane including the optical axis 1a (straight line). The light intensity uniformizing element 6 is configured by joining light intensity uniformizing sections 61 and 62 for uniforming the intensity distribution of light beams in the direction of the optical axis 1a. The light intensity uniformizing units 61 and 62 use different types of light intensity uniformizing units 61 and 62 so that the uniformization characteristics of the intensity distribution of the light flux change at the joint surface of the light intensity uniformizing units 61 and 62. ing.

光強度均一化部６１を光軸１ａと垂直な面で切断した場合の光強度均一化部６１の断面形状（入射面６１ａおよび出射面６１ｂの面形状）は、２．５ｍｍ×１．５ｍｍの矩形であり、光強度均一化部６２の断面形状（入射面６２ａおよび出射面６２ｂの面形状）は光強度均一化部６１の断面形状よりも大きな６ｍｍ×４ｍｍの矩形である。また、光強度均一化部６１および光強度均一化部６２は、ともに光軸１ａ方向の長さが３０ｍｍである。また、光強度均一化部６１，６２は、ともに屈折率１．５２のガラスロッドで形成されている。図３では、光強度均一化素子６内を通過する光線６４Ａおよび光線６４Ｂを、Ｆ値１．０（片側３０度の拡がり角）を持つ光束の最外周の光線として示している。 The cross-sectional shape (surface shape of the incident surface 61a and the exit surface 61b) of the light intensity uniformizing unit 61 when the light intensity uniformizing unit 61 is cut along a plane perpendicular to the optical axis 1a is 2.5 mm × 1.5 mm. The cross-sectional shape of the light intensity uniformizing portion 62 (surface shape of the incident surface 62a and the exit surface 62b) is a 6 mm × 4 mm rectangle larger than the cross-sectional shape of the light intensity uniformizing portion 61. The light intensity uniformizing unit 61 and the light intensity uniformizing unit 62 both have a length of 30 mm in the direction of the optical axis 1a. The light intensity uniformizing portions 61 and 62 are both formed of glass rods having a refractive index of 1.52. In FIG. 3, the light beam 64 A and the light beam 64 B that pass through the light intensity uniformizing element 6 are shown as the outermost light beams of a light beam having an F value of 1.0 (a divergence angle of 30 degrees on one side).

図３において、光線６４Ａおよび光線６４Ｂの光強度均一化素子６内における反射回数は、光強度均一化部６１において７回であり、光強度均一化部６２において３回であり、光強度均一化素子６の全体では合計１０回となる。 In FIG. 3, the number of reflections of the light beam 64A and the light beam 64B in the light intensity uniformizing element 6 is 7 times in the light intensity uniformizing unit 61 and 3 times in the light intensity uniformizing unit 62. The total of the element 6 is 10 times.

ここで、光強度均一化素子６を従来の単一な形状で形成した場合について説明する。図４は、従来の光強度均一化素子の断面図である。従来の光強度均一化素子１０６は、光強度均一化部６２と同じ形状の断面積（入射面１０６ａや出射面１０６ｂの面積が６ｍｍ×４ｍｍ）であり、光軸１ａ方向の長さは光強度均一化部６１と光強度均一化部６２を合わせた６０ｍｍであるとする。この場合、光強度均一化素子１０６内を通過する光線１６４Ａと光線１６４Ｂの光強度均一化素子１０６内での反射回数は５回となる。このように、従来の光強度均一化素子１０６は、本実施の形態の光強度均一化素子６（図３の光強度均一化素子６）と比べて反射回数が半減しているので、十分な光強度均一化効果を得ることができない。従来の光強度均一化素子１０６に十分な光強度均一化効果を与えるためには、光強度均一化素子１０６の長さを、光強度均一化素子６の２倍（１２０ｍｍ）にする必要があり、光強度均一化素子１０６のレイアウトに多大な影響を与えてしまうことになる。 Here, a case where the light intensity uniformizing element 6 is formed in a conventional single shape will be described. FIG. 4 is a cross-sectional view of a conventional light intensity uniformizing element. The conventional light intensity uniformizing element 106 has a cross-sectional area having the same shape as the light intensity uniformizing section 62 (the area of the entrance surface 106a and the exit surface 106b is 6 mm × 4 mm), and the length in the optical axis 1a direction is the light intensity. It is assumed that the thickness is 60 mm including the uniformizing portion 61 and the light intensity uniformizing portion 62. In this case, the number of reflections of the light beam 164A and the light beam 164B passing through the light intensity uniformizing element 106 within the light intensity uniformizing element 106 is five. As described above, the conventional light intensity uniformizing element 106 has a sufficient number of reflections by half compared to the light intensity uniformizing element 6 of the present embodiment (the light intensity uniformizing element 6 in FIG. 3). The effect of uniforming light intensity cannot be obtained. In order to give a sufficient light intensity uniforming effect to the conventional light intensity uniformizing element 106, the length of the light intensity uniformizing element 106 needs to be twice that of the light intensity uniformizing element 6 (120 mm). As a result, the layout of the light intensity uniformizing element 106 is greatly affected.

なお、図３に示した光強度均一化部６２の出射面６２ｂおよび、図４に示した光強度均一化素子１０６の出射面１０６ｂの断面形状は例えば６ｍｍ×４ｍｍとする。この断面形状のサイズは、反射型ライトバルブ２と光強度均一化素子６，１０６の光学的な関係において決定される大きさであり、光強度均一化素子６，１０６に同じ照明光学系７を使用する限りこの大きさに決定される。 Note that the cross-sectional shapes of the exit surface 62b of the light intensity uniformizing unit 62 shown in FIG. 3 and the exit surface 106b of the light intensity uniformizing element 106 shown in FIG. 4 are, for example, 6 mm × 4 mm. The size of the cross-sectional shape is determined by the optical relationship between the reflective light valve 2 and the light intensity uniformizing elements 6 and 106. The same illumination optical system 7 is provided to the light intensity uniformizing elements 6 and 106. This size is determined as long as it is used.

光線６４Ａ，６４Ｂは、光強度均一化素子６内での反射回数が少ないと、光強度均一化素子６からの出射する光束の光強度を十分に均一化することができなくなる。さらに、本実施の形態では、投写型表示装置１に３原色のレーザ光源４１を採用するとともに、光ファイバ４３を用いて光強度均一化素子６に導く構成を採用している。この場合の、光強度均一化素子６の入射面６１ａにおける光ファイバ４３の配置例について説明する。図５は、光ファイバの配置例を説明するための図である。図５では、光ファイバ４３を光路と垂直な平面で切断した場合の断面図（入射面６１ａ）を示している。 If the number of reflections of the light beams 64A and 64B in the light intensity uniformizing element 6 is small, the light intensity of the light beam emitted from the light intensity uniformizing element 6 cannot be sufficiently uniformed. Further, in the present embodiment, a laser light source 41 of three primary colors is employed in the projection display device 1 and a configuration in which the light intensity equalizing element 6 is guided using an optical fiber 43 is employed. An arrangement example of the optical fiber 43 on the incident surface 61a of the light intensity equalizing element 6 in this case will be described. FIG. 5 is a diagram for explaining an arrangement example of optical fibers. FIG. 5 shows a cross-sectional view (incident surface 61a) when the optical fiber 43 is cut along a plane perpendicular to the optical path.

例えば、赤色、緑色、青色の各レーザ光源４１から出射される光束を導く光ファイバ４３として、赤色用の光ファイバ４３Ｒ、緑色用の光ファイバ４３Ｇ、青色用の光ファイバ４３Ｂの計３本を用いる。この場合、光強度均一化素子６の入射面６１ａには、例えば図５に示すように、３色の光束が分離した状態となるよう、赤色用の光ファイバ４３Ｒ、緑色用の光ファイバ４３Ｇ、青色用の光ファイバ４３Ｂが配置される。光強度均一化素子６は、３色の光束を混色するとともに、光束の光強度を均一化するという作用も必要となるので、従来のランプ光源を用いた光学系よりもさらに光強度均一化の効果が必要になる場合が多い。 For example, a total of three optical fibers 43R, a green optical fiber 43G, and a blue optical fiber 43B are used as the optical fibers 43 that guide the light beams emitted from the red, green, and blue laser light sources 41. . In this case, on the incident surface 61a of the light intensity uniformizing element 6, for example, as shown in FIG. 5, the red optical fiber 43R, the green optical fiber 43G, A blue optical fiber 43B is disposed. The light intensity uniformizing element 6 is required to mix three color light fluxes and to uniformize the light intensity of the light flux. Therefore, the light intensity uniformizing element 6 can make the light intensity even more uniform than an optical system using a conventional lamp light source. In many cases, an effect is required.

本実施の形態の投写型表示装置１では、光源に３原色のレーザ光源４１を採用した場合であっても、２つの光強度均一化部６１，６２で光強度均一化素子６を構成しているので光強度均一化の効果を容易に高めることが可能になる。換言すると、光源に従来のランプ光源を採用した場合よりも光強度均一化素子６における光強度均一化の効果を高める必要がある場合であっても、光強度均一化の効果を容易に高めることが可能となる。 In the projection display device 1 of the present embodiment, even when the three primary color laser light sources 41 are employed as the light source, the light intensity uniformizing element 6 is configured by the two light intensity uniformizing sections 61 and 62. Therefore, the effect of uniforming the light intensity can be easily increased. In other words, even when it is necessary to enhance the light intensity uniforming effect in the light intensity uniformizing element 6 as compared with the case where a conventional lamp light source is adopted as the light source, the light intensity uniforming effect can be easily enhanced. Is possible.

なお、図３では光強度均一化素子６における光強度均一化部６１と光強度均一化部６２を、屈折率１．５２のガラスロッドで構成した場合について説明したが、光強度均一化部６１，６２は他の構成であってもよい。 In FIG. 3, the case where the light intensity uniformizing unit 61 and the light intensity uniformizing unit 62 in the light intensity uniformizing element 6 are configured by glass rods having a refractive index of 1.52 is described. , 62 may have other configurations.

図６および図７は、光強度均一化素子の他の構成例を示す図である。図６では、種類が同じ部材の光強度均一化部で光強度均一化素子６を構成した場合を示し、図７では、種類が異なる部材の光強度均一化部で光強度均一化素子６を構成した場合を示している。図６の光強度均一化素子６では、光強度均一化素子６における光強度均一化部６１と光強度均一化部６２を、光反射面を内側にして筒状に組み合わせたライトパイプで構成している。 6 and 7 are diagrams showing another configuration example of the light intensity uniformizing element. FIG. 6 shows a case where the light intensity equalizing element 6 is configured by the light intensity equalizing part of the same type of member, and FIG. 7 shows the case where the light intensity equalizing element 6 is configured by the light intensity equalizing part of the different type of member. The case where it comprises is shown. In the light intensity uniformizing element 6 of FIG. 6, the light intensity uniformizing section 61 and the light intensity uniformizing section 62 in the light intensity uniformizing element 6 are configured by light pipes that are combined in a cylindrical shape with the light reflecting surface inside. ing.

光強度均一化部６１および光強度均一化部６２をライトパイプで構成した場合、光強度均一化素子６の入射面６１ａへの入射角度を保存しながら、内側を向く表面鏡の反射作用を利用して光強度均一化部６１，６２内を光伝播させることになる。これにより、図３に示したようなガラスロッドの光強度均一化部６１，６２と比較して、光強度均一化素子６を短く構成することが可能となる。 When the light intensity uniformizing section 61 and the light intensity uniformizing section 62 are configured by light pipes, the reflection effect of the surface mirror facing inward is used while preserving the incident angle to the incident surface 61a of the light intensity uniformizing element 6. As a result, the light intensity uniformizing portions 61 and 62 are propagated. Accordingly, the light intensity uniformizing element 6 can be configured to be shorter than the light intensity uniformizing sections 61 and 62 of the glass rod as shown in FIG.

図６では、光強度均一化部６１の開口形状を２．５ｍｍ×１．５ｍｍで構成し、光強度均一化部６２の開口形状を６ｍｍ×４ｍｍで構成した場合を示している。また、ここでの光強度均一化部６１および光強度均一化部６２は、ともに光軸１ａ方向の長さが２０ｍｍである。また、図６でも図３と同様に、光強度均一化素子６内を通過する光線６４Ａおよび光線６４Ｂを、Ｆ値１．０（片側３０度の拡がり角）を持つ光束の最外周の光線として示している。 FIG. 6 shows a case where the opening shape of the light intensity uniformizing section 61 is configured by 2.5 mm × 1.5 mm, and the opening shape of the light intensity uniformizing section 62 is configured by 6 mm × 4 mm. The light intensity uniformizing unit 61 and the light intensity uniformizing unit 62 here both have a length in the direction of the optical axis 1a of 20 mm. Also in FIG. 6, as in FIG. 3, the light beam 64 A and the light beam 64 B that pass through the light intensity uniformizing element 6 are used as the outermost light beams of the light beam having F value 1.0 (30-degree divergence angle on one side) Show.

図６に示した光強度均一化部６１は、その長さが２０ｍｍであり、図３に示した光強度均一化部６１の長さ（３０ｍｍ）よりも短いが、光線６４Ａ，６４Ｂは光強度均一化部６１内で８回反射している。これは、図３に示した光強度均一化部６１での光線６４Ａ，６４Ｂの反射回数（７回）よりも多い。 The light intensity uniformizing unit 61 shown in FIG. 6 has a length of 20 mm, which is shorter than the length (30 mm) of the light intensity uniformizing unit 61 shown in FIG. Reflected eight times in the uniformizing part 61. This is more than the number of reflections (seven times) of the light beams 64A and 64B at the light intensity uniformizing unit 61 shown in FIG.

また、図６に示した光強度均一化部６２は、その長さが２０ｍｍであり、図３に示した光強度均一化部６２の長さ（３０ｍｍ）よりも短いが、光線６４Ａ，６４Ｂは光強度均一化部６２内で３回反射している。これは、図３に示した光強度均一化部６１での光線６４Ａ，６４Ｂの反射回数（３回）と同じ回数である。これにより、図６に示した光強度均一化部６１，６２内では、光線６４Ａ，６４Ｂが合計１１回反射することになる。 Further, the light intensity uniformizing unit 62 shown in FIG. 6 has a length of 20 mm, which is shorter than the length (30 mm) of the light intensity uniformizing unit 62 shown in FIG. Reflected three times in the light intensity uniformizing section 62. This is the same number of times of reflection (three times) of the light beams 64A and 64B at the light intensity uniformizing unit 61 shown in FIG. As a result, the light beams 64A and 64B are reflected a total of 11 times in the light intensity uniformizing sections 61 and 62 shown in FIG.

このように、光強度均一化素子６をガラスロッドで構成した場合、光路長の６０ｍｍ間で光線６４Ａ，６４Ｂが１０回反射するのに対し、光強度均一化素子６をライトパイプで構成した場合、光路長の４０ｍｍ間で光線６４Ａ，６４Ｂが１１回反射することになる。したがって、光強度均一化素子６をライトパイプで構成した場合、光強度均一化素子６をガラスロッドで構成した場合よりも、光強度の均一化に関して同等以上の効果がある。 As described above, when the light intensity uniformizing element 6 is formed of a glass rod, the light beams 64A and 64B are reflected 10 times within an optical path length of 60 mm, whereas the light intensity uniformizing element 6 is formed of a light pipe. The light rays 64A and 64B are reflected 11 times within the optical path length of 40 mm. Therefore, when the light intensity uniformizing element 6 is formed of a light pipe, the same or better effect can be obtained with respect to uniform light intensity than when the light intensity uniformizing element 6 is formed of a glass rod.

また、光強度均一化素子６を、光強度均一化素子６の材料と空気界面との全反射作用を利用して反射させるガラスロッドや樹脂ロッドで構成した場合、空気界面との反射による光量の損失はなく、光利用効率を高めることが可能となる。 Further, when the light intensity uniformizing element 6 is configured by a glass rod or a resin rod that reflects using the total reflection action between the material of the light intensity uniformizing element 6 and the air interface, the amount of light due to reflection from the air interface is reduced. There is no loss, and the light utilization efficiency can be increased.

また、光強度均一化素子６を、内側を向く表面鏡の反射作用を利用するライトパイプで構成した場合、光路長が短くなるととともに、光強度均一化部６１と光強度均一化部６２の結合および冷却保持が容易になる。 Further, when the light intensity uniformizing element 6 is configured by a light pipe that uses the reflection action of the surface mirror facing inward, the optical path length is shortened and the light intensity uniformizing section 61 and the light intensity uniformizing section 62 are coupled. In addition, cooling and holding becomes easy.

さらに、光強度均一化部６１をガラスロッドで構成し、光強度均一化部６２をライトパイプで構成してもよい。図７は、光強度均一化部６１をガラスロッドとライトパイプで構成した場合の光強度均一化素子６を示している。図７に示す光強度均一化素子６は、図３や図６に示した光強度均一化素子６の構成例と同等の光強度均一化機能を実現するために、光強度均一化部６１の開口形状が２．５ｍｍ×１．５ｍｍで構成されるとともに長さが３０ｍｍで構成され、光強度均一化部６２の形状が６ｍｍ×４ｍｍで構成されるとともに長さが２０ｍｍで構成されている。この構成により、光強度均一化素子６内での光線６４Ａ，６４Ｂの総反射回数は１０回となり、図３や図６に示した光強度均一化素子６と同等の光強度均一化の効果を得ることができる。 Furthermore, the light intensity uniformizing unit 61 may be configured with a glass rod, and the light intensity uniformizing unit 62 may be configured with a light pipe. FIG. 7 shows the light intensity uniformizing element 6 in the case where the light intensity uniformizing section 61 is composed of a glass rod and a light pipe. The light intensity uniformizing element 6 shown in FIG. 7 has a light intensity uniformizing unit 61 in order to realize a light intensity uniformizing function equivalent to the configuration example of the light intensity uniformizing element 6 shown in FIGS. The opening shape is 2.5 mm × 1.5 mm and the length is 30 mm. The light intensity uniformizing portion 62 is 6 mm × 4 mm and the length is 20 mm. With this configuration, the total number of reflections of the light beams 64A and 64B within the light intensity uniformizing element 6 is 10, and the light intensity uniformizing effect equivalent to that of the light intensity uniformizing element 6 shown in FIGS. Obtainable.

図７に示すように、光強度均一化部６１をガラスロッドで構成し、光強度均一化部６２をライトパイプで構成することによって、ガラスロッドとライトパイプの双方の利点を活かすことが可能となる。具体的には、光強度均一化部６１をガラスロッドで構成することによって、光利用効率を良好に保つことが可能になる。また、光強度均一化部６２をライトパイプで構成することによって、光強度均一化部６１と光強度均一化部６２の結合が容易になるとともに、光強度均一化素子６の光路長を短く構成することが可能となる。 As shown in FIG. 7, it is possible to make use of the advantages of both the glass rod and the light pipe by configuring the light intensity uniformizing section 61 with a glass rod and configuring the light intensity uniformizing section 62 with a light pipe. Become. Specifically, by configuring the light intensity uniformizing unit 61 with a glass rod, it is possible to keep the light utilization efficiency favorable. Further, by configuring the light intensity uniformizing section 62 with a light pipe, the light intensity uniformizing section 61 and the light intensity uniformizing section 62 can be easily combined and the optical path length of the light intensity uniformizing element 6 can be shortened. It becomes possible to do.

なお、図７の光強度均一化素子６は、光強度均一化部６１をガラスロッドで構成し、光強度均一化部６２をライトパイプで構成したが、光強度均一化部６１をライトパイプで構成し、光強度均一化部６２をガラスロッドで構成してもよい。また、各光強度均一化部６１，６２の長さは、上述した構成例に限らず、投写型表示装置１に要求される光強度均一化の効果（光強度均一化度合）、レイアウトからの制約またはコスト等に応じて決定されるものである。 In the light intensity uniformizing element 6 of FIG. 7, the light intensity uniformizing section 61 is configured by a glass rod, and the light intensity uniformizing section 62 is configured by a light pipe. However, the light intensity uniformizing section 61 is configured by a light pipe. The light intensity uniformizing unit 62 may be formed of a glass rod. The lengths of the light intensity uniformizing units 61 and 62 are not limited to the above-described configuration example, but the light intensity uniforming effect (light intensity uniformization degree) required for the projection display apparatus 1 and the layout It is determined according to constraints or costs.

また、本実施の形態では、光強度均一化素子６を光強度均一化部６１と光強度均一化部６２の２つで構成をした場合について説明したが、光強度均一化素子６を３つ以上の光強度均一化部で構成してもよい。図８は、３つの光強度均一化部で構成された光強度均一化素子の構成を示す図である。図８に示す光強度均一化素子６は、３つの光強度均一化部６１，６２，６３で構成されている。光強度均一化部６３は、光強度均一化部６１，６２と同様の構成を有しており、重複する説明は省略する。 Further, in the present embodiment, the case where the light intensity uniformizing element 6 is configured by the light intensity uniformizing section 61 and the light intensity uniformizing section 62 has been described, but three light intensity uniformizing elements 6 are provided. You may comprise by the above light intensity equalization part. FIG. 8 is a diagram illustrating a configuration of a light intensity uniformizing element including three light intensity uniformizing units. The light intensity equalizing element 6 shown in FIG. 8 includes three light intensity equalizing sections 61, 62, and 63. The light intensity uniformizing unit 63 has the same configuration as the light intensity uniformizing units 61 and 62, and a duplicate description is omitted.

光強度均一化部６１は、入射面６１ａが光ファイバ４３側を向き、出射面６１ｂが光強度均一化部６２を向くよう光強度均一化素子６内に配設されている。また、光強度均一化部６２は、入射面６２ａが光強度均一化部６１側を向き、出射面６２ｂが光強度均一化部６２を向くよう光強度均一化素子６内に配設されている。また、光強度均一化部６３は、入射面６３ａが光強度均一化部６２側を向き、出射面６３ｂが照明光学系７を向くよう光強度均一化素子６内に配設されている。また、光強度均一化部６３を光軸１ａ方向で切断した場合の光強度均一化部６３の断面形状（入射面６３ａ）は、光強度均一化部６２の断面形状（出射面６２ｂ）よりも大きな矩形である。 The light intensity uniformizing section 61 is disposed in the light intensity uniformizing element 6 so that the incident surface 61a faces the optical fiber 43 side and the emission surface 61b faces the light intensity uniformizing section 62. The light intensity uniformizing unit 62 is disposed in the light intensity uniformizing element 6 so that the incident surface 62a faces the light intensity uniformizing unit 61 side and the output surface 62b faces the light intensity uniformizing unit 62. . Further, the light intensity uniformizing section 63 is disposed in the light intensity uniformizing element 6 so that the incident surface 63a faces the light intensity uniformizing section 62 side and the emission surface 63b faces the illumination optical system 7. Further, the cross-sectional shape (incident surface 63a) of the light intensity uniformizing unit 63 when the light intensity uniformizing unit 63 is cut in the direction of the optical axis 1a is larger than the cross-sectional shape (exiting surface 62b) of the light intensity uniformizing unit 62. A large rectangle.

また、光強度均一化素子６の照明光学系７側の光強度均一化部（図３、図６、図７における光強度均一化部６２や図８における光強度均一化部６３）の断面形状は反射型ライトバルブ２と照明光学系７の性能から決定されるが、その他の断面形状（例えば、図３、図６、図７における光強度均一化部６１、および図８における光強度均一化部６１，６２）は、投写型表示装置１に求める光強度均一化性能や光ファイバ４３の配置等を鑑みて決定すればよい。 Further, the cross-sectional shape of the light intensity uniformizing section (the light intensity uniformizing section 62 in FIGS. 3, 6, and 7 and the light intensity uniformizing section 63 in FIG. 8) on the illumination optical system 7 side of the light intensity uniformizing element 6. Is determined from the performance of the reflective light valve 2 and the illumination optical system 7, but other cross-sectional shapes (for example, the light intensity uniformizing portion 61 in FIGS. 3, 6, and 7 and the light intensity uniformizing in FIG. 8). The units 61 and 62) may be determined in view of the light intensity uniformization performance required for the projection display device 1, the arrangement of the optical fiber 43, and the like.

なお、本実施の形態では、投写型表示装置１の光源４としてレーザ光源４１を用いる場合について説明したが、光源４として発光ダイオードを用いてもよい。この場合であっても、光源４としてレーザ光源４１を用いた場合と同様の効果を得ることができる。 In the present embodiment, the case where the laser light source 41 is used as the light source 4 of the projection display device 1 has been described. However, a light emitting diode may be used as the light source 4. Even in this case, the same effect as when the laser light source 41 is used as the light source 4 can be obtained.

また、図７では光強度均一化部６１、光強度均一化部６２として、部材の種類および断面形状の両方が異なる部材を用いる場合について説明したが、光強度均一化部６１、光強度均一化部６２として、断面形状が同じ部材であって部材の種類が異なる部材を用いてもよい。図９は、種類が異なる部材の光強度均一化部で光強度均一化素子を構成した場合の光強度均一化素子の他の構成例を示す図である。図９では、光強度均一化素子６を、断面形状が同じ光強度均一化部６１、光強度均一化部６２で構成した場合を示している。ここでの光強度均一化素子６は、光強度均一化部６１がガラスロッドで構成され、光強度均一化部６２がライトパイプで構成されている。このように、光強度均一化部６１をガラスロッドで構成しているので、光利用効率を良好に保つことが可能になる。また、光強度均一化部６２をライトパイプで構成しているので、光強度均一化部６１と光強度均一化部６２の結合が容易になるとともに、光強度均一化素子６の光路長を短く構成することが可能となる。 Further, FIG. 7 illustrates the case where members having different types of members and cross-sectional shapes are used as the light intensity uniformizing unit 61 and the light intensity uniformizing unit 62. However, the light intensity uniformizing unit 61 and the light intensity uniformizing unit are described. As the part 62, members having the same cross-sectional shape and different types of members may be used. FIG. 9 is a diagram illustrating another configuration example of the light intensity uniformizing element in the case where the light intensity uniformizing element is configured by the light intensity uniformizing portions of different types of members. FIG. 9 shows a case where the light intensity uniformizing element 6 includes a light intensity uniformizing section 61 and a light intensity uniformizing section 62 having the same cross-sectional shape. In the light intensity uniformizing element 6 here, the light intensity uniformizing section 61 is configured by a glass rod, and the light intensity uniformizing section 62 is configured by a light pipe. Thus, since the light intensity equalizing part 61 is comprised with the glass rod, it becomes possible to keep light utilization efficiency favorable. In addition, since the light intensity uniformizing unit 62 is configured by a light pipe, the light intensity uniformizing unit 61 and the light intensity uniformizing unit 62 can be easily combined and the optical path length of the light intensity uniformizing element 6 can be shortened. It can be configured.

なお、図９では、光強度均一化部６１をガラスロッドで構成し、光強度均一化部６２をライトパイプで構成する場合について説明したが、光強度均一化部６１をライトパイプで構成し、光強度均一化部６２をガラスロッドで構成してもよい。 In addition, in FIG. 9, although the light intensity equalization part 61 was comprised with the glass rod and the case where the light intensity equalization part 62 was comprised with a light pipe was demonstrated, the light intensity equalization part 61 was comprised with a light pipe, The light intensity uniformizing unit 62 may be formed of a glass rod.

このように、投写型表示装置１は、光強度均一化部６１，６２が複数種類の光強度均一化部（光強度均一化部６１，６２や光強度均一化部６１〜６３）で構成されているので、コンパクトな構成（短い光路長）で光強度および色ムラの均一化効果を高めることが可能となる。 As described above, in the projection display apparatus 1, the light intensity uniformizing units 61 and 62 are configured by a plurality of types of light intensity uniformizing units (the light intensity uniformizing units 61 and 62 and the light intensity uniformizing units 61 to 63). Therefore, it is possible to enhance the effect of uniforming light intensity and color unevenness with a compact configuration (short optical path length).

また、光強度均一化素子６内の複数の光強度均一化部を異なる形状で構成しているので、同一形状の光強度均一化部で光強度均一化素子６を構成する場合よりもコンパクトな構成で光強度および色ムラの均一化効果を高めることが可能となる。 In addition, since the plurality of light intensity equalizing portions in the light intensity equalizing element 6 are configured in different shapes, the light intensity equalizing element 6 is more compact than the case where the light intensity equalizing elements 6 having the same shape are configured. With the configuration, it is possible to enhance the effect of uniforming light intensity and color unevenness.

また、光強度均一化素子６の少なくとも１つの光強度均一化部を管状部材にしてその内面で光束を反射させるように光強度均一化素子６を構成した場合には、光強度均一化部の結合、冷却および保持が容易になるとともに、光強度均一化素子６の光路長を短く構成できるので光学系をコンパクトに構成することが可能となる。 Further, when the light intensity uniformizing element 6 is configured such that at least one light intensity uniformizing part of the light intensity uniformizing element 6 is a tubular member and the light beam is reflected by the inner surface thereof, The coupling, cooling, and holding are facilitated, and the optical path length of the light intensity uniformizing element 6 can be shortened, so that the optical system can be configured compactly.

また、光強度均一化素子６の少なくとも１つの光強度均一化部を透明材料の多角柱状部材で構成したので、光強度均一化素子６の設計が容易になるとともに光利用効率を高めることが可能となる。また、光強度均一化素子６は、複数の光強度均一化部を一体化して形成されているので、安価に光強度均一化素子６を得ることが可能となる。 Further, since at least one light intensity uniformizing portion of the light intensity uniformizing element 6 is formed of a polygonal columnar member made of a transparent material, the light intensity uniformizing element 6 can be easily designed and the light use efficiency can be increased. It becomes. In addition, since the light intensity uniformizing element 6 is formed by integrating a plurality of light intensity uniformizing parts, the light intensity uniformizing element 6 can be obtained at low cost.

また、複数の光強度均一化部のうち最も照明光学系７側に配置された光強度均一化部の断面形状を、反射型ライトバルブ２の被照明面２ｂの形状と略相似形としているので、光利用効率が高くなり、照度分布が良好な光学系を構成することが可能となる。 In addition, since the cross-sectional shape of the light intensity uniformizing portion disposed closest to the illumination optical system 7 among the plurality of light intensity uniformizing portions is substantially similar to the shape of the illuminated surface 2b of the reflective light valve 2. It becomes possible to construct an optical system with high light utilization efficiency and good illuminance distribution.

また、光源をレーザ光源４１で構成したので、寿命が長く色再現性がよい明るい光学系を構成することができる。また、光源から出射された光束を光ファイバ４３を用いて光強度均一化素子６に導く構成としたので、光学系の配置に柔軟性を待たせることが可能になるとともに、光学系での光束の取り込み効率を高めることが可能となる。 Further, since the light source is composed of the laser light source 41, a bright optical system having a long life and good color reproducibility can be constructed. In addition, since the light beam emitted from the light source is guided to the light intensity uniformizing element 6 using the optical fiber 43, it is possible to wait for flexibility in the arrangement of the optical system and the light beam in the optical system. Can be improved.

このように実施の形態によれば、光強度均一化素子６を複数種類の光強度均一化部で構成しているので、多原色の光源を採用した光学系においても、小さな構成で照度分布（光強度および色ムラの）の均一性を向上させることが可能となる。 As described above, according to the embodiment, the light intensity uniformizing element 6 is configured by a plurality of types of light intensity uniformizing sections. Therefore, even in an optical system employing a multi-primary light source, the illuminance distribution ( It is possible to improve the uniformity of light intensity and color unevenness.

以上のように、本発明に係る投写型表示装置は、スクリーン上への画像の投写表示に適している。 As described above, the projection display device according to the present invention is suitable for projecting and displaying an image on a screen.

実施の形態に係る投写型表示装置の光学系の概略構成を示す図である。It is a figure which shows schematic structure of the optical system of the projection type display apparatus which concerns on embodiment. 照明光学系内の光伝播を説明するための図である。It is a figure for demonstrating the light propagation in an illumination optical system. 光強度均一化素子の断面図である。It is sectional drawing of a light intensity equalization element. 従来の光強度均一化素子の断面図である。It is sectional drawing of the conventional light intensity equalization element. 光ファイバの配置例を説明するための図である。It is a figure for demonstrating the example of arrangement | positioning of an optical fiber. 同種部材の光強度均一化部からなる光強度均一化素子の構成を示す図である。It is a figure which shows the structure of the light intensity equalization element which consists of a light intensity equalization part of the same kind member. 異種部材の光強度均一化部からなる光強度均一化素子の構成を示す図である。It is a figure which shows the structure of the light intensity equalization element which consists of a light intensity equalization part of a dissimilar member. ３つの光強度均一化部からなる光強度均一化素子の構成を示す図である。It is a figure which shows the structure of the light intensity equalization element which consists of three light intensity equalization parts. 異種部材の光強度均一化部からなる光強度均一化素子の他の構成例を示す図である。It is a figure which shows the other structural example of the light intensity equalization element which consists of a light intensity equalization part of a dissimilar member.

Explanation of symbols

１投写型表示装置
１ａ，２ａ光軸
２反射型ライトバルブ
２ｂ被照明面
３投写光学系
４光源
６光強度均一化素子
７照明光学系
４１レーザ光源
４２集光光学系
４３光ファイバ
６１〜６３光強度均一化部
６１ａ，６２ａ，６３ａ入射面
６１ｂ，６２ｂ，６３ｂ出射面
６４Ａ，６４Ｂ光線 DESCRIPTION OF SYMBOLS 1 Projection type display apparatus 1a, 2a Optical axis 2 Reflection type light valve 2b Illuminated surface 3 Projection optical system 4 Light source 6 Light intensity equalization element 7 Illumination optical system 41 Laser light source 42 Condensing optical system 43 Optical fiber 61-63 Light Intensity equalization part 61a, 62a, 63a Incident surface 61b, 62b, 63b Outgoing surface 64A, 64B Ray

Claims

A projection type having a light source and a light intensity uniformizing element for uniformizing the intensity distribution of the light beam emitted from the light source, and performing projection display of an image using the light beam emitted from the light intensity uniformizing element In the display device,
The projection display device, wherein the light intensity uniformizing element includes a plurality of light intensity uniformizing sections that uniformize the intensity distribution.

The projection display device according to claim 1, wherein cross-sectional shapes of the plurality of light intensity uniformizing portions are different.

The projection display device according to claim 1, wherein the plurality of light intensity uniformizing units have different types of members.

The at least one light intensity uniformizing unit among the light intensity uniformizing units is configured to include a tubular member that reflects a light beam on an inner surface thereof. Projection display device.

The at least one light intensity uniformizing unit among the light intensity uniformizing units is configured to include a transparent polygonal columnar member that reflects a light beam therein. The projection display device according to item.

The projection display device according to claim 1, wherein the light intensity uniformizing unit is formed by integrating different types of light intensity uniformizing units.

The projection display device according to claim 1, wherein the light source emits multi-primary light.