JPH11202132A - Polarizing prism and reflection type optical modulating projector - Google Patents
Polarizing prism and reflection type optical modulating projectorInfo
- Publication number
- JPH11202132A JPH11202132A JP10008352A JP835298A JPH11202132A JP H11202132 A JPH11202132 A JP H11202132A JP 10008352 A JP10008352 A JP 10008352A JP 835298 A JP835298 A JP 835298A JP H11202132 A JPH11202132 A JP H11202132A
- Authority
- JP
- Japan
- Prior art keywords
- light
- polarized light
- transmits
- transparent medium
- polarized
- 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
Links
Landscapes
- Transforming Electric Information Into Light Information (AREA)
- Video Image Reproduction Devices For Color Tv Systems (AREA)
- Optical Elements Other Than Lenses (AREA)
- Polarising Elements (AREA)
Abstract
Description
【0001】[0001]
【発明の属する技術分野】本発明は、反射型光変調プロ
ジェクタの光学系の光路長を短縮して小型化するための
偏光プリズム及びこれを用いた反射型光変調プロジェク
タに関する。[0001] 1. Field of the Invention [0002] The present invention relates to a polarizing prism for shortening the optical path length of an optical system of a reflection type light modulation projector for downsizing, and a reflection type light modulation projector using the same.
【0002】[0002]
【従来の技術】図10は、従来の反射型光変調プロジェ
クタの1例の光学系の概念図である。ランプ81a、反
射鏡81b等からなる光源81からの光線を、赤色反
射、緑・青色透過のダイクロイックミラー101で赤色
光線を反射する。その赤色光線を、S偏光を反射し、P
偏光を透過する赤用のPBS(偏光ビームスプリッタ)
103rに入射し、透過するP偏光で反射型LCD等か
らなる赤用の偏光変調素子85rで偏光変調し、PBS
103rに戻す。PBS103rで反射して光変調され
たS偏光を、赤色光線透過、緑・青光線反射のダイクロ
イックミラー105を透過して投写レンズ108でスク
リーンに投写する。同様に、ダイクロイックミラー10
1を透過する緑・青色光線を、緑色光線反射、青色光線
透過のダイクロイックミラー102に入射する。ダイク
ロイックミラー102で反射する緑色光線を緑用のPB
S103gと偏光変調素子85gで光変調して、緑色光
線反射、青色光線透過のダイクロイックミラー104と
ダイクロイックミラー105で反射して、投写レンズ1
08に入射する。また、青用PBS103bと偏光変調
素子85bでダイクロイックミラー102を透過する青
色光線を光変調して、投写レンズ108に入射し、赤、
緑、青の各光線をスクリーンに投写してカラーの映像表
示を行う。しかし、このような反射型光変調プロジェク
タの光学系の構成では、PBSとは別に、少なくとも4
枚の各種のダイクロイックミラーが必要となる。そのた
め、反射型光変調素子と投写レンズ間の光路長が長くな
り、バックフォーカスの長いレンズが必要となことか
ら、開口比の小さいレンズの製作が困難となり、解像度
・明るさの点で不利となる。さらには、光学系が大型と
なるため、プロジェクタの小型軽量化が図れない等の問
題があった。2. Description of the Related Art FIG. 10 is a conceptual diagram of an example of an optical system of a conventional reflection type light modulation projector. A light beam from a light source 81 including a lamp 81a and a reflecting mirror 81b is reflected by a dichroic mirror 101 that reflects red light and transmits green and blue light. The red ray reflects S-polarized light and
Red PBS (polarizing beam splitter) that transmits polarized light
The polarization-modulating element 85r for red composed of a reflective LCD or the like modulates the polarization with the P-polarized light that enters and passes through 103r, and the PBS.
Return to 103r. The S-polarized light reflected and modulated by the PBS 103r passes through a dichroic mirror 105 that transmits red light and reflects green and blue light, and is projected on a screen by a projection lens. Similarly, the dichroic mirror 10
The green and blue light beams that pass through 1 enter a dichroic mirror 102 that reflects green light and transmits blue light. The green light reflected by the dichroic mirror 102 is converted to a green PB
The light is modulated by S103g and the polarization modulation element 85g, and reflected by the dichroic mirror 104 and the dichroic mirror 105 that reflect green light and transmit blue light, and the projection lens 1
08. Further, the blue PBS 103b and the polarization modulation element 85b modulate the light of the blue light passing through the dichroic mirror 102, enter the projection lens 108,
The green and blue light beams are projected on the screen to display a color image. However, in the configuration of the optical system of such a reflection type light modulation projector, apart from the PBS, at least 4
Various types of dichroic mirrors are required. As a result, the optical path length between the reflection type light modulation element and the projection lens becomes longer, and a lens with a longer back focus is required.Therefore, it becomes difficult to manufacture a lens having a small aperture ratio, which is disadvantageous in terms of resolution and brightness. Become. Further, there is a problem that the size of the optical system becomes large, so that the size and weight of the projector cannot be reduced.
【0003】[0003]
【発明が解決しようとする課題】本発明は上記問題点に
鑑みなされたもので、反射型光変調プロジェクタの光学
系の光路長を短縮して小型化するための偏光プリズムと
これを用いた反射型光変調プロジェクタを提供すること
を目的とする。SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and a polarizing prism for shortening the optical path length of an optical system of a reflection-type light modulation projector and miniaturizing the same, and a reflection prism using the same. It is an object of the present invention to provide a light modulation type projector.
【0004】[0004]
【課題を解決するための手段】2つ三角柱透明媒体の張
り合わせ面に光学薄膜を形成して分光特性をもつ偏光ビ
ームスプリッタ機能を備えた偏光プリズムにおいて、張
り合わせ面に両面相互間の光学的干渉を回避するに足る
厚さの平行平面を有する板状透明媒体を介在させ、同板
状透明媒体の一方の面と前記一方の三角柱透明媒体との
間に一方の偏光光を透過しこれと直交する他方の偏光光
に対して分光特性を備えて反射する光学薄膜を形成し、
同板状透明媒体の他方の面と前記他方の三角柱透明媒体
との間に前記他方の偏光光を透過し前記一方の偏光光に
対して分光特性を備えて反射する光学薄膜を形成し、前
記一方の偏光光及びこれと前記直交する他方の偏光光に
対して相互に独立した分光特性もつ偏光ビームスプリッ
タ機能を備えた偏光プリズムを得る。SUMMARY OF THE INVENTION In a polarizing prism having a polarizing beam splitter function having a spectral characteristic by forming an optical thin film on a bonding surface of two triangular prism transparent media, optical interference between both surfaces is reduced by the bonding surface. A plate-shaped transparent medium having a parallel plane of sufficient thickness to be avoided is interposed, and one polarized light beam is transmitted between one surface of the plate-shaped transparent medium and the one triangular prism transparent medium and is orthogonal to this. Form an optical thin film that reflects the other polarized light with spectral characteristics,
Forming an optical thin film that transmits the other polarized light and reflects the one polarized light with spectral characteristics between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium, A polarizing prism having a polarizing beam splitter function having spectral characteristics independent of one polarized light and the other polarized light orthogonal to the polarized light is obtained.
【0005】前記三角柱透明媒体及び板状媒体は、略同
質の光学ガラスから構成する。[0005] The triangular prism transparent medium and the plate-like medium are made of optical glass of substantially the same quality.
【0006】前記三角柱媒体は前記板状媒体部分をくり
抜いた光学ガラスからなり、同くり抜き部分の光学ガラ
スの両面に前記光学薄膜を形成し、前記板状媒体は、同
くり抜き部分に充填した同光学ガラスと略同一屈折率の
液体とする。The triangular prism medium is made of optical glass obtained by hollowing out the plate-shaped medium portion, and the optical thin film is formed on both sides of the optical glass at the hollowed-out portion. A liquid having a refractive index substantially equal to that of glass.
【0007】前記2つの三角柱媒体は、中空の透明媒体
からなる四角柱と、両面に前記光学薄膜を形成した前記
板状媒体で同四角柱の中空部内の対角を結んで分割して
2つの中空三角柱とし、同2つの中空三角柱の各中空部
に板状媒体と略同一屈折率の液体を充填して構成する。The two triangular prism media are divided into two parts by connecting a diagonal in the hollow part of the quadrangular prism with the quadrangular prism formed of a hollow transparent medium and the plate-shaped medium having the optical thin film formed on both surfaces thereof. A hollow triangular prism is formed by filling each hollow portion of the two hollow triangular prisms with a liquid having substantially the same refractive index as the plate-shaped medium.
【0008】前記板状透明媒体の一方の面と一方の三角
柱透明媒体との間の光学薄膜は、P偏光光を透過し所定
波長以上のS偏光光を透過し所定波長以下のS偏光光を
反射する特性を備え、板状透明媒体の他方の面と他方の
三角柱透明媒体との間の光学薄膜は、S偏光光を透過し
所定波長以下のP偏光光を透過し所定波長以上のP偏光
光を反射する特性を備える。The optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits P-polarized light, transmits S-polarized light having a predetermined wavelength or more, and transmits S-polarized light having a predetermined wavelength or less. The optical thin film between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium has the property of reflecting light, transmits S-polarized light, transmits P-polarized light of a predetermined wavelength or less, and P-polarized light of a predetermined wavelength or more. It has the property of reflecting light.
【0009】前記板状透明媒体の一方の面と一方の三角
柱透明媒体との間の光学薄膜は、S偏光光を透過し所定
波長以上のP偏光光を透過し所定波長以下のP偏光光を
反射する特性を備え、板状透明媒体の他方の面と他方の
三角柱透明媒体との間の光学薄膜は、P偏光光を透過し
所定波長以下のS偏光光を透過し所定の波長以上のS偏
光光を反射する特性を備える。An optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits S-polarized light, transmits P-polarized light having a predetermined wavelength or more, and converts P-polarized light having a predetermined wavelength or less. The optical thin film between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium has a property of reflecting light, transmits P-polarized light, transmits S-polarized light having a predetermined wavelength or less, and transmits S-polarized light having a predetermined wavelength or less. It has the property of reflecting polarized light.
【0010】前記板状透明媒体の一方の面と一方の三角
柱透明媒体との間の光学薄膜は、P偏光光の白色光
(W)を透過しS偏光光の緑及び赤色光(Y)を透過し
青色光(B)を反射する特性を備え、板状透明媒体の他
方の面と他方の三角柱透明媒体との間の光学薄膜は、S
偏光光の白色光(W)を透過しP偏光光の青色光(B)
を透過し緑及び青色光(Y)を反射する特性を備える。An optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits white light (W) of P-polarized light and transmits green and red light (Y) of S-polarized light. The optical thin film having the property of transmitting and reflecting the blue light (B) between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium has S
Transmits white light (W) of polarized light and blue light (B) of P-polarized light
And reflects green and blue light (Y).
【0011】前記板状透明媒体の一方の面と一方の三角
柱透明媒体との間の光学薄膜は、S偏光光の白色光
(W)を透過しP偏光光の緑及び赤色光(Y)を透過し
青色光(B)を反射する特性を備え、板状透明媒体の他
方の面と他方の三角柱透明媒体との間の光学薄膜は、P
偏光光の白色光(W)を透過しS偏光光の青色光(B)
を透過し緑及び青色光(Y)を反射する特性を備える。An optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits S-polarized light white light (W) and transmits P-polarized light green and red light (Y). It has the property of transmitting and reflecting blue light (B), and the optical thin film between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium is P
S-polarized blue light (B) that transmits polarized white light (W)
And reflects green and blue light (Y).
【0012】前記板状透明媒体の一方の面と一方の三角
柱透明媒体との間の光学薄膜は、P偏光光の白色光
(W)を透過しS偏光光の赤色光(R)を透過し青及び
緑色光(C)を反射する特性を備え、板状透明媒体の他
方の面と他方の三角柱透明媒体との間の光学薄膜は、S
偏光光の白色光(W)を透過しP偏光光の青及び緑色光
(C)を透過し赤色光(R)を反射する特性を備える。The optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits P-polarized light white light (W) and S-polarized light red light (R). The optical thin film having the property of reflecting blue and green light (C) and between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium has S
It has the characteristic of transmitting white light (W) of polarized light, transmitting blue and green light (C) of P-polarized light, and reflecting red light (R).
【0013】前記板状透明媒体の一方の面と一方の三角
柱透明媒体との間の光学薄膜は、S偏光光の白色光
(W)を透過しP偏光光の赤色光(R)を透過し青及び
緑色光(C)を反射する特性を備え、板状透明媒体の他
方の面と他方の三角柱透明媒体との間の光学薄膜は、P
偏光光の白色光(W)を透過しS偏光光の青及び緑色光
(C)を透過し赤色光(R)を反射する特性を備える。An optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits S-polarized light white light (W) and P-polarized light red light (R). The optical thin film having the property of reflecting blue and green light (C) and between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium has P
It has the property of transmitting white light (W) of polarized light, transmitting blue and green light (C) of S-polarized light, and reflecting red light (R).
【0014】前記板状透明媒体の一方の面と一方の三角
柱透明媒体との間の光学薄膜は、P偏光光の白色光
(W)を透過しS偏光光の赤色光(R)を透過し青色光
(B)を反射する特性を備え、板状透明媒体の他方の面
と他方の三角柱透明媒体との間の光学薄膜は、S偏光光
の白色光(W)を透過しP偏光光の青色光(B)を透過
し赤色光(R)を反射する特性を備える。The optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits P-polarized light white light (W) and S-polarized light red light (R). The optical thin film between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium has the property of reflecting blue light (B) and transmits white light (W) of S-polarized light and transmits P-polarized light. It has the property of transmitting blue light (B) and reflecting red light (R).
【0015】前記板状透明媒体の一方の面と一方の三角
柱透明媒体との間の光学薄膜は、S偏光光の白色光
(W)を透過しP偏光光の赤色光(R)を透過し青色光
(B)を反射する特性を備え、板状透明媒体の他方の面
と他方の三角柱透明媒体との間の光学薄膜は、P偏光光
の白色光(W)を透過しS偏光光の青色光(B)を透過
し赤色光(R)を反射する特性を備える。An optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits S-polarized light white light (W) and P-polarized light red light (R). The optical thin film between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium has the property of reflecting blue light (B) and transmits white light (W) of P-polarized light and transmits S-polarized light. It has the property of transmitting blue light (B) and reflecting red light (R).
【0016】前記板状透明媒体の一方の面と一方の三角
柱透明媒体との間の光学薄膜は、P偏光光の白色光
(W)を透過しS偏光光の青色光及び赤色光(M)を透
過し緑色光(G)を反射する特性を備え、板状透明媒体
の他方の面と他方の三角柱透明媒体との間の光学薄膜
は、S偏光光の白色光(W)を透過しP偏光光の緑色光
(G)を透過し青色光及び赤色光(M)を反射する特性
を備える。An optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits P-polarized light white light (W) and S-polarized light blue light and red light (M). , And has a characteristic of reflecting green light (G), and the optical thin film between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium transmits S-polarized light white light (W) and transmits P light. It has the property of transmitting polarized green light (G) and reflecting blue light and red light (M).
【0017】前記板状透明媒体の一方の面と一方の三角
柱透明媒体との間の光学薄膜は、S偏光光の白色光
(W)を透過しP偏光光の青色光及び赤色光(M)を透
過し緑色光(G)を反射する特性を備え、板状透明媒体
の他方の面と他方の三角柱透明媒体との間の光学薄膜
は、P偏光光の白色光(W)を透過しS偏光光の緑色光
(G)を透過し青色光及び赤色光(M)を反射する特性
を備える。An optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits S-polarized light white light (W) and P-polarized light blue light and red light (M). And the property of reflecting green light (G) is transmitted through the optical thin film between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium. It has the property of transmitting polarized green light (G) and reflecting blue light and red light (M).
【0018】複数の反射型の偏光変調素子と偏光プリズ
ムの組合せにより光源からの光線を変調して投写レンズ
でスクリーン上に投写してカラーの映像を表示する反射
型光変調プロジェクタにおいて、前記光源からの光線を
P偏光とするポラライザと、同P偏光の内の緑色光線を
反射し青及び赤色光線を透過するダイクロイックミラー
と、同反射した緑色光線のP偏光光を反射しS偏光光を
透過する偏光ビームスプリッタ(以下PBSという)
と、同PBSで反射したP偏光の緑色光線を受け偏光変
調して反射し同PBSに再入射する緑用の偏光変調素子
と、前記ダイクロイックミラーを透過する青色光線及び
赤色光線の内青色光線のP偏光光を反射しS偏光光を透
過し赤色光線のP偏光光を透過しS偏光光を反射する偏
光プリズムと、同偏光プリズムで反射する青色光線のP
偏光光を受け偏光変調して反射して同偏光プリズムに再
入射する青用の偏光変調素子と、同偏光プリズムを透過
する赤色光線のP偏光光を受けて偏光変調して反射して
同偏光プリズムに再入射する赤用の偏光変調素子と、同
偏光プリズムで同プリズムに再入射した青色光線のS偏
光光を透過して検光し赤色光線のS偏光光を反射して検
光し、前記PBSに再入射する緑色光線を同PBSで検
光して出射し、前記プリズムから出射する青及び赤色光
を透過し前記PBSから出射する緑色光を反射するダイ
クロイックミラーと、同ダイクロイックミラーから出射
する青、赤及び緑色光線を入射して投写する投写レンズ
を備えた反射型光変調プロジェクタとする。In a reflection type light modulation projector for displaying a color image by modulating a light beam from a light source by a combination of a plurality of reflection type polarization modulation elements and a polarizing prism, and projecting it on a screen by a projection lens. A polarizer that makes P light polarized light, a dichroic mirror that reflects green light of the P polarized light and transmits blue and red light, and a P light that reflects the reflected green light and transmits S polarized light Polarizing beam splitter (PBS)
And a polarization modulation element for green which receives a P-polarized green light reflected by the PBS, modulates the polarization, reflects the reflected light, and reenters the PBS, and a blue light and a red light transmitted through the dichroic mirror. A polarizing prism that reflects P-polarized light, transmits S-polarized light, transmits red P-polarized light, and reflects S-polarized light;
Polarization-modulating element for blue which receives polarized light, modulates and reflects it, and re-enters the same polarizing prism, and receives P-polarized light of red light transmitted through the same polarizing prism, and modulates and reflects the same to reflect the same polarized light. A polarization modulator for red that re-enters the prism, and the S-polarized light of the blue light that re-enters the prism with the same polarization prism is transmitted and analyzed, and the S-polarized light of the red light is reflected and analyzed. A dichroic mirror that detects and emits the green light beam re-entering the PBS with the same PBS, transmits blue and red light emitted from the prism, and reflects the green light emitted from the PBS, and emits the same from the dichroic mirror To be a reflection type light modulation projector having a projection lens for projecting and projecting blue, red and green light rays.
【0019】複数の反射型の偏光変調素子と偏光プリズ
ムの組合せにより光源からの光線を変調して投写レンズ
でスクリーン上に投写してカラーの映像を表示する反射
型光変調プロジェクタにおいて、前記光源からの光線の
内のP偏光光を透過しS偏光光を反射するPBSと、同
PBSを反射するS偏光の内緑色光線を透過しP偏光光
を反射する第一の偏光プリズムと、同偏光プリズムを透
過する緑色光線を受け偏光変調して反射し同偏光プリズ
ムに再入射する緑用の偏光変調素子と、前記PBSを透
過するP偏光の内青色光線を反射し青色光線のS偏光光
を透過し赤色光線を透過し赤色光線のP偏光光を反射す
る第二の偏光プリズムと、同偏光プリズムで反射する青
色光線のP偏光光を受け偏光変調して反射して同偏光プ
リズムに再入射する青用の偏光変調素子と、同偏光プリ
ズムを透過する赤色光線のP偏光光を受け偏光変調して
反射して同偏光プリズムに再入射する赤用の偏光変調素
子と、同偏光プリズムに再入射した青色光線を検光しS
偏光光を透過し赤色光線を検光してS偏光光を反射して
出射し、前記第一の偏光プリズムに再入射する緑色光線
を反射して検光しP偏光光を出射し、これら出射する青
及び赤色光線を透過し緑色光線を反射するダイクロイッ
クミラーと、同ダイクロイックミラーから出射する青、
赤及び緑色光線を入射して投写する投写レンズを備えた
反射型光変調プロジェクタとする。A reflection type light modulation projector for modulating a light beam from a light source with a combination of a plurality of reflection type polarization modulation elements and a polarizing prism and projecting it on a screen with a projection lens to display a color image. A PBS that transmits P-polarized light and reflects S-polarized light, a first polarizing prism that transmits S-polarized green light reflected by the PBS and reflects P-polarized light, And a green polarization modulator that receives and modulates the polarized green light, reflects the reflected green light, and reenters the same polarizing prism, and reflects the blue light of the P-polarized light transmitted through the PBS and transmits the S-polarized light of the blue light. And a second polarizing prism that transmits the red light beam and reflects the P-polarized light of the red light, and receives the P-polarized light of the blue light reflected by the same polarizing prism, modulates and reflects the light, and reenters the same polarizing prism. A polarization modulator for blue, a P-polarized light of red light transmitted through the same polarization prism, polarization-modulated, reflected and re-entered the same polarization prism, and re-entered the same polarization prism Analyze the blue light
The polarized light is transmitted, the red light is detected, the S-polarized light is reflected and emitted, and the green light re-entering the first polarizing prism is reflected and analyzed, and the P-polarized light is emitted. A dichroic mirror that transmits blue and red rays and reflects a green ray, and blue emitted from the dichroic mirror,
It is assumed that the projector is a reflection type light modulation projector provided with a projection lens for projecting red and green light rays.
【0020】[0020]
【発明の実施の形態】本発明の実施の形態について、図
を用いて説明する。図1は、本発明による偏光プリズム
の1実施例の平面概念図である。2つ三角柱透明媒体と
して光学ガラスからなる2つの三角柱1a、1cの間
に、同じ材質の光学ガラスからなる板状媒体としての薄
板ガラス1bを挟んで張り合わせる。薄板ガラス1bの
厚さは、張り合わせ面の両面相互間の光学的干渉を回避
するに十分な厚さ、すなわち光の波長と比較して十分厚
いものとする。三角柱1a及び1cと薄板ガラス1bの
間1ab及び1bcには、従来の技術により光学薄膜を
形成して、三角柱1aと薄板ガラス1bの間1abに
は、一方の偏光光例えばP偏光光を透過しこれと直交す
る他方の偏光光例えばS偏光光の透過光及び反射光に対
して分光特性を持たせる。また、三角柱1cと薄板ガラ
ス1bとの間1bcには、他方の偏光光例えばS偏光光
を透過しこれと直交する一方の偏光光例えばP偏光光の
透過光及び反射光に対して分光特性を持たせる。このよ
うにして、一方の偏光光例えばP偏光光とこれと直交す
る他方の偏光光例えばS偏光光に対して相互に独立した
透過光及び反射光の分光特性をもつ偏光ビームスプリッ
タ機能を備えた偏光プリズム1を得ることができる。DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a conceptual plan view of an embodiment of the polarizing prism according to the present invention. The two thin triangular prisms 1a and 1c made of optical glass as a transparent medium are laminated with a thin glass plate 1b as a plate-shaped medium made of optical glass of the same material sandwiched therebetween. The thickness of the thin glass plate 1b is set to a thickness sufficient to avoid optical interference between both surfaces of the bonding surface, that is, a thickness sufficiently large as compared with the wavelength of light. An optical thin film is formed between the triangular prisms 1a and 1c and the thin glass plate 1ab and 1bc by a conventional technique, and one polarized light, for example, P-polarized light is transmitted through the 1ab between the triangular prism 1a and the thin glass plate 1b. Spectral characteristics are imparted to the other polarized light orthogonal to this, for example, transmitted light and reflected light of S-polarized light. In addition, a portion 1bc between the triangular prism 1c and the thin glass plate 1b transmits the other polarized light, for example, S-polarized light, and has a spectral characteristic with respect to the transmitted light and reflected light of one polarized light, for example, P-polarized light orthogonal to the other. To have. In this manner, a polarizing beam splitter function having spectral characteristics of transmitted light and reflected light that is independent of one polarized light, for example, P-polarized light and the other polarized light, for example, S-polarized light, is provided. The polarizing prism 1 can be obtained.
【0021】図2は、本発明による偏光プリズムの別の
実施例の平面概念図である。三角柱透明媒体及び板状媒
体は、上記のように三角柱のガラスと板ガラスから構成
することができるが、光学ガラス等からなる四角柱2の
対角部分を薄板状にくり抜いて、くり抜き部分2bの光
学ガラス2の両面2ab、2bcに前記の光学薄膜を形
成し、くり抜き部分2bには、光学ガラス2と略同一屈
折率の液体2bを充填して構成することもできる。この
構成では、高度な技術を要する光学ガラス相互間の光学
的な接着が不要となる。FIG. 2 is a conceptual plan view of another embodiment of the polarizing prism according to the present invention. The triangular prism transparent medium and the plate-like medium can be composed of triangular prism glass and plate glass as described above. The optical thin film may be formed on both surfaces 2ab and 2bc of the glass 2 and the hollow portion 2b may be filled with a liquid 2b having substantially the same refractive index as the optical glass 2. This configuration eliminates the need for optical bonding between optical glasses that requires advanced technology.
【0022】図3は、本発明による偏光プリズムのさら
に別の実施例の平面概念図である。三角柱透明媒体及び
板状媒体は、板ガラス等から構成した中空の透明媒体か
らなる四角柱3と、四角柱3の内部の対角に両面3a
b、3bcに前記の光学薄膜を形成した薄板ガラス3b
を挟在させる。四角柱3の内部の薄板ガラス3bで分割
された2つの中空三角柱部分には、板ガラス等と略同一
屈折率の液体を充填して構成する。FIG. 3 is a conceptual plan view of still another embodiment of the polarizing prism according to the present invention. The triangular prism transparent medium and the plate-shaped medium are made up of a quadrangular prism 3 made of a hollow transparent medium made of sheet glass or the like,
b, 3bc, the thin glass 3b having the optical thin film formed thereon
Interposed. The two hollow triangular prism portions divided by the thin glass plate 3b inside the quadrangular prism 3 are filled with a liquid having substantially the same refractive index as that of the glass plate or the like.
【0023】図4は、本発明による偏光プリズムの1実
施例の(A)板状媒体の一方の面における透過分光特
性、(B)板状媒体の他方の面における透過分光特性、
(C)偏光プリズム総合の透過分光特性である。ここ
で、Tは光線の透過率を表す。例えば図1の板ガラス1
bの一方の面1abでは、P偏光光Lpの白色光線Lp
wを透過し、S偏光光Lsの青色光線Lsbを反射しS
偏光光Lsの緑色光G及び赤色光Rすなわち黄色光
(Y)を透過する特性とする。板ガラス1bの他方の面
1bcでは、S偏光光Lsの白色光Lswを透過し、P
偏光光Lpの青色光Lpbを透過しP偏光光Lpの緑色
光G及び赤色光Rすなわち黄色光(Y)を反射する特性
とする。このようにすることで、総合では、P偏光光L
pは青色光Bを透過し、緑色光G及び赤色光Rすなわち
黄色光(Y)を反射し、S偏光光Lsは青色光Bを反射
し、緑色光G及び赤色光Rすなわち黄色光(Y)を透過
する特性の偏光プリズムが得られる。同様にして、この
偏光プリズムとP偏光光とS偏光光との分光特性を逆に
した偏光プリズムも得られる。FIG. 4 shows (A) transmission spectral characteristics on one surface of a plate-like medium, (B) transmission spectral characteristics on the other surface of a plate-like medium, and FIG.
(C) Transmission spectral characteristics of the polarizing prism as a whole. Here, T represents the light transmittance. For example, the sheet glass 1 of FIG.
b, the white light Lp of the P-polarized light Lp
w, and reflects the blue light Lsb of the S-polarized light Ls
It has a property of transmitting the green light G and the red light R of the polarized light Ls, that is, the yellow light (Y). On the other surface 1bc of the plate glass 1b, the white light Lsw of the S-polarized light Ls is transmitted, and P
It has a characteristic of transmitting the blue light Lpb of the polarized light Lp and reflecting the green light G and the red light R of the P-polarized light Lp, that is, the yellow light (Y). By doing so, the P-polarized light L
p transmits blue light B and reflects green light G and red light R, that is, yellow light (Y). S-polarized light Ls reflects blue light B, and green light G and red light R, that is, yellow light (Y). ) Can be obtained. Similarly, a polarizing prism in which the spectral characteristics of the polarizing prism and the P-polarized light and the S-polarized light are reversed can be obtained.
【0024】図5は、本発明による偏光プリズムの1実
施例の(A)板状媒体の一方の面における透過分光特
性、(B)板状媒体の他方の面における透過分光特性、
(C)偏光プリズム総合の透過分光特性である。ここで
も、Tは光線の透過率を表す。上記と同様に、例えば図
1の板ガラス1bの一方の面1abでは、P偏光光Lp
の白色光線Lpwを透過し、S偏光光Lsの青色光B及
び緑色光Gすなわちシアン色光(C)を反射し赤色光R
を透過する特性とする。板ガラス1bの他方の面1bc
では、S偏光光Lsの白色光Lswを透過し、P偏光光
Lpの青色光B及び緑色光Gすなわちシアン色光(C)
を透過し赤色光Rを反射する特性とする。このようにす
ることで、総合では、P偏光光Lpはシアン色光(C)
を透過し、赤色光Rを反射し、S偏光光Lsはシアン色
光(C)を反射し、赤色光Rを透過する特性の偏光プリ
ズムが得られる。同様にして、この偏光プリズムとP偏
光光とS偏光光との分光特性を逆にした偏光プリズムも
得られる。FIG. 5 shows (A) transmission spectral characteristics on one surface of a plate-like medium, (B) transmission spectral characteristics on the other surface of a plate-like medium, and FIG.
(C) Transmission spectral characteristics of the polarizing prism as a whole. Again, T represents the light transmittance. Similarly to the above, for example, on one surface 1ab of the plate glass 1b of FIG.
Of the S-polarized light Ls, and reflects the blue light B and the green light G, that is, the cyan light (C), and the red light R
To transmit light. The other surface 1bc of the sheet glass 1b
Then, the white light Lsw of the S-polarized light Ls is transmitted, and the blue light B and the green light G of the P-polarized light Lp, that is, the cyan light (C)
And red light R is reflected. By doing so, the P-polarized light Lp is converted into cyan light (C) as a whole.
, The red light R is reflected, the S-polarized light Ls reflects the cyan light (C), and a polarizing prism having characteristics of transmitting the red light R is obtained. Similarly, a polarizing prism in which the spectral characteristics of the polarizing prism and the P-polarized light and the S-polarized light are reversed can be obtained.
【0025】図6は、本発明による偏光プリズムの1実
施例の総合の透過分光特性である。ここでも、Tは光線
の透過率を表す。上記と同様に、例えば図1の板ガラス
1bの一方の面1abでは、P偏光光Lpの白色光線L
pwを透過し、S偏光光Lsの青色光Bを反射し赤色光
Rを透過する特性とする。板ガラス1bの他方の面1b
cでは、S偏光光Lsの白色光Lswを透過し、P偏光
光Lpの青色光Bを透過し赤色光Rを反射する特性とす
る。このようにすることで、総合では、P偏光光Lpは
青色光Bを透過し、赤色光Rを反射し、S偏光光Lsは
青色光Bを反射し、赤色光Rを透過する特性の偏光プリ
ズムが得られる。この場合は、緑色光部分の特性が任意
で良く偏光プリズムの製作が容易となる。同様にして、
この偏光プリズムのP偏光光とS偏光光との分光特性を
逆にした偏光プリズムも得られる。FIG. 6 shows the overall transmission spectral characteristics of one embodiment of the polarizing prism according to the present invention. Again, T represents the light transmittance. Similarly to the above, for example, on one surface 1ab of the plate glass 1b in FIG.
pw, transmit blue light B of S-polarized light Ls, and transmit red light R. The other side 1b of the sheet glass 1b
In c, the white light Lsw of the S-polarized light Ls is transmitted, the blue light B of the P-polarized light Lp is transmitted, and the red light R is reflected. By doing so, the P-polarized light Lp transmits the blue light B, reflects the red light R, and the S-polarized light Ls reflects the blue light B and transmits the red light R. A prism is obtained. In this case, the characteristics of the green light portion are arbitrary and the polarizing prism can be easily manufactured. Similarly,
A polarizing prism in which the spectral characteristics of the P-polarized light and the S-polarized light of the polarizing prism are reversed can also be obtained.
【0026】図7は、本発明による偏光プリズムの1実
施例の総合の透過分光特性である。ここでも、Tは光線
の透過率を表す。上記と同様に、例えば図1の板ガラス
1bの一方の面1abでは、P偏光光Lpの白色光線L
pwを透過し、S偏光光Lsの青色光B及び赤色光Rす
なわちマゼンタ色光(M)を透過し緑色光(G)を反射
する特性とする。また、板ガラス1bの他方の面1bc
では、S偏光光Lsの白色光(W)を透過しP偏光光の
緑色光(G)を透過し青色光B及び赤色光Rすなわちマ
ゼンタ色光(M)を反射する特性とする。このようにす
ることで、総合では、P偏光光Lpは緑色光Gを透過
し、青色光B及び赤色光Rすなわちマゼンタ色光(M)
を反射し、S偏光光Lsは緑色光Gを反射し、青色光B
及び赤色光Rすなわちマゼンタ色光(M)を透過する特
性となる偏光プリズムが得られる。同様にして、この偏
光プリズムのP偏光光とS偏光光との分光特性を逆にし
た偏光プリズムも得られる。FIG. 7 shows the overall transmission spectral characteristics of one embodiment of the polarizing prism according to the present invention. Again, T represents the light transmittance. Similarly to the above, for example, on one surface 1ab of the plate glass 1b in FIG.
pw, transmit blue light B and red light R of S-polarized light Ls, that is, transmit magenta light (M) and reflect green light (G). Also, the other surface 1bc of the sheet glass 1b
In this case, white light (W) of S-polarized light Ls is transmitted, green light (G) of P-polarized light is transmitted, and blue light B and red light R, that is, magenta light (M) are reflected. By doing so, the P-polarized light Lp transmits the green light G and the blue light B and the red light R, that is, the magenta color light (M).
, The S-polarized light Ls reflects the green light G, and the blue light B
And a polarizing prism having a characteristic of transmitting the red light R, that is, the magenta light (M). Similarly, a polarizing prism in which the spectral characteristics of the P-polarized light and the S-polarized light of the polarizing prism are reversed can be obtained.
【0027】図8は、本発明による反射型光変調プロジ
ェクタの1実施例の光学系の概念図である。ランプ81
a及び反射鏡81b等からなる光源81からの略平行な
光線L0を、ポラライザ82でP偏光Lpとする。P偏
光Lpを緑色光線を反射し青及び赤色光線を透過するダ
イクロイックミラー83で、緑色光線Lpgと青及び赤
色光すなわちマゼンタ色光Lpmとする。緑色光線Lp
gをP偏光光の緑色光線のP偏光光を反射しS偏光光を
透過するPBS84で反射して、緑色光線を受け偏光変
調して反射する偏光変調素子85gに入射する。偏光変
調素子85gから偏光変調して反射された緑色光をPB
S84に再入射して検光し、S偏光光だけを透過し、緑
色光反射のダイクロイックミラー87で反射して、投写
レンズ88に入射する。一方、ダイクロイックミラー8
3を透過したマゼンタ色光Lpmは、青色光線のP偏光
光を反射しS偏光光を透過し赤色光線のP偏光光を透過
しS偏光光を反射する偏光プリズム86に入射する。偏
光プリズム86で反射する青色光線のP偏光光を、青用
の偏光変調素子85bに入射して偏光変調して反射し、
偏光プリズム86に再入射する。再入射した青色光線を
S偏光光だけ透過する偏光プリズム86で検光して、青
色光及び赤色光を透過するダイクロイックミラー87で
上記緑色光と合成して投写レンズ88に入射する。同様
に、偏光プリズム86を透過する赤色光のP偏光光を、
赤用の偏光変調素子85rに入射して偏光変調して反射
して偏光プリズム86に再入射する。赤色光のS偏光光
のみを反射する偏光プリズム86で反射して検光し、ダ
イクロイックミラー87で他の色光と合成する。ダイク
ロイックミラー87で合成した青、赤及び緑色光線を入
射する投写レンズでスクリーンに投写してカラー画像を
表示することで、反射型光変調プロジェクタが得られ
る。このような光学系の構成にすることで、上記製作の
容易な偏光プリズムが利用できる。FIG. 8 is a conceptual diagram of an optical system of one embodiment of the reflection type light modulation projector according to the present invention. Lamp 81
The substantially parallel light beam L0 from the light source 81 including the light source a and the reflecting mirror 81b is converted into the P-polarized light Lp by the polarizer 82. The P-polarized light Lp is converted into green light Lpg and blue and red light, that is, magenta light Lpm, by a dichroic mirror 83 that reflects green light and transmits blue and red light. Green ray Lp
g is reflected by the PBS 84, which reflects the P-polarized green light of the P-polarized light and transmits the S-polarized light, and enters the polarization modulation element 85g, which receives the green light, modulates and reflects the green light. The green light reflected by the polarization modulation from the polarization modulation element 85g is subjected to PB
The light is re-entered at S84 and analyzed, only S-polarized light is transmitted, reflected by the dichroic mirror 87 that reflects green light, and is incident on the projection lens 88. On the other hand, dichroic mirror 8
The magenta light Lpm that has passed through 3 enters a polarizing prism 86 that reflects P-polarized light of blue light, transmits S-polarized light, transmits P-polarized light of red light, and reflects S-polarized light. The P-polarized light of the blue light reflected by the polarizing prism 86 is incident on a blue polarization modulation element 85b, and is polarized and modulated to be reflected.
Re-enter the polarizing prism 86. The re-entered blue light is analyzed by a polarizing prism 86 that transmits only S-polarized light, combined with the green light by a dichroic mirror 87 that transmits blue light and red light, and is incident on a projection lens 88. Similarly, the red P-polarized light transmitted through the polarizing prism 86 is
The light is incident on the polarization modulation element 85r for red, is polarization-modulated, is reflected, and is incident again on the polarization prism 86. The light is reflected and analyzed by a polarizing prism 86 that reflects only the S-polarized light of red light, and is combined with another color light by a dichroic mirror 87. By projecting the blue, red, and green light rays synthesized by the dichroic mirror 87 onto a screen with a projection lens that enters the light, and displaying a color image, a reflection-type light modulation projector can be obtained. With such an optical system configuration, a polarizing prism that can be easily manufactured can be used.
【0028】図9は、本発明による反射型光変調プロジ
ェクタの他の実施例の光学系の概念図である。上記と同
様に。ランプ81a及び反射鏡81b等からなる光源8
1からの略平行な光線L0を、S偏光の緑色光Lsgを
反射し、P偏光のマゼンタ色光Lpmを透過する第一の
偏光プリズム93で分離する。分離したS偏光の緑色光
LsgはP偏光光を反射しS偏光光を透過するPBS9
4を透過して、緑色光線を受け偏光変調して反射する偏
光変調素子85gに入射する。偏光変調素子85gから
偏光変調して反射された緑色光はPBS94に再入射し
てP偏光光だけを反射して検光し、緑色光反射のダイク
ロイックミラー87で反射する。一方、偏光プリズム9
3を透過したマゼンタ色光Lpmは、青色光線のP偏光
光を反射しS偏光光を透過し赤色光線のP偏光光を透過
しS偏光光を反射する第二の偏光プリズム86に入射す
る。偏光プリズム86で反射する青色光線のP偏光光
を、青用の偏光変調素子85bに入射して偏光変調して
反射し、偏光プリズム86に再入射する。再入射した青
色光線をS偏光光だけ透過する偏光プリズム86で検光
して、青色光及び赤色光を透過するダイクロイックミラ
ー87で上記緑色光と合成して投写レンズ88に入射す
る。同様に、偏光プリズム86を透過する赤色光のP偏
光光を、赤用の偏光変調素子85rに入射して偏光変調
して反射して偏光プリズム86に再入射する。赤色光の
S偏光光のみを反射する偏光プリズム86で反射して検
光し、ダイクロイックミラー87で他の色光と合成す
る。ダイクロイックミラー87で合成した青、赤及び緑
色光線を入射する投写レンズでスクリーンに投写してカ
ラー画像を表示することで、反射型光変調プロジェクタ
が得られる。このような光学系の構成でも、上記製作の
容易な偏光プリズムが使用できる。FIG. 9 is a conceptual diagram of an optical system of another embodiment of the reflection type light modulation projector according to the present invention. As above. Light source 8 including lamp 81a and reflecting mirror 81b
The substantially parallel light beam L0 from 1 is separated by the first polarizing prism 93 that reflects the S-polarized green light Lsg and transmits the P-polarized magenta light Lpm. The separated S-polarized green light Lsg reflects P-polarized light and transmits S-polarized light.
4 and is incident on a polarization modulation element 85g that receives and modulates and reflects the green light. The green light that has been polarization-modulated and reflected from the polarization modulation element 85g is incident again on the PBS 94, reflects and analyzes only the P-polarized light, and is reflected by the green light reflecting dichroic mirror 87. On the other hand, the polarizing prism 9
The magenta light Lpm that has passed through 3 enters a second polarizing prism 86 that reflects P-polarized light of blue light, transmits S-polarized light, transmits P-polarized light of red light, and reflects S-polarized light. The blue P-polarized light reflected by the polarizing prism 86 is incident on the blue polarization modulation element 85b, is polarization-modulated and reflected, and is incident again on the polarization prism 86. The re-entered blue light is analyzed by a polarizing prism 86 that transmits only S-polarized light, combined with the green light by a dichroic mirror 87 that transmits blue light and red light, and is incident on a projection lens 88. Similarly, the P-polarized light of red light transmitted through the polarizing prism 86 is incident on the polarization modulator 85r for red, is polarization-modulated, is reflected, and is incident on the polarization prism 86 again. The light is reflected and analyzed by a polarizing prism 86 that reflects only the S-polarized light of red light, and is combined with another color light by a dichroic mirror 87. By projecting the blue, red, and green light rays synthesized by the dichroic mirror 87 onto a screen with a projection lens that enters the light, and displaying a color image, a reflection-type light modulation projector can be obtained. Even with such an optical system configuration, a polarizing prism that can be easily manufactured as described above can be used.
【0029】[0029]
【発明の効果】以上説明したように、2つ三角柱透明媒
体の張り合わせ面に光学薄膜を形成して分光特性をもつ
偏光ビームスプリッタ機能を備えた偏光プリズムにおい
て、張り合わせ面に両面相互間の光学的干渉を回避する
に足る厚さの平行平面を有する板状透明媒体を介在さ
せ、同板状透明媒体の一方の面と前記一方の三角柱透明
媒体との間に一方の偏光光を透過しこれと直交する他方
の偏光光に対して分光特性を備えて反射する光学薄膜を
形成し、同板状透明媒体の他方の面と前記他方の三角柱
透明媒体との間に前記他方の偏光光を透過し前記一方の
偏光光に対して分光特性を備えて反射する光学薄膜を形
成し、前記一方の偏光光及びこれと前記直交する他方の
偏光光に対して相互に独立した分光特性もつ偏光ビーム
スプリッタ機能を備えた偏光プリズムを得ることがで
き、これを用いて反射型光変調プロジェクタを構成する
ことで、光学系の光路長を短縮して小型化が可能な反射
型光変調プロジェクタを提供するができる。As described above, in a polarizing prism having a polarizing beam splitter function having a spectral characteristic by forming an optical thin film on a bonding surface of two triangular prism transparent media, the optical surface between both surfaces is formed on the bonding surface. A plate-shaped transparent medium having a parallel plane having a thickness sufficient to avoid interference is interposed, and one polarized light is transmitted between one surface of the plate-shaped transparent medium and the one triangular prism transparent medium, and Forming an optical thin film that reflects the other orthogonal polarized light with spectral characteristics and transmits the other polarized light between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium. A polarizing beam splitter function that forms an optical thin film that reflects the one polarized light with spectral characteristics and has spectral characteristics independent from each other for the one polarized light and the other polarized light orthogonal to the polarized light. Be prepared Polarizing prism can be obtained, by configuring the reflective optical modulation projector using this, it provides a reflective optical modulation projector can be downsized by shortening the optical path length of the optical system.
【図1】本発明による偏光プリズムの1実施例の平面概
念図である。FIG. 1 is a schematic plan view of an embodiment of a polarizing prism according to the present invention.
【図2】本発明による偏光プリズムの別の実施例の平面
概念図である。FIG. 2 is a schematic plan view of another embodiment of the polarizing prism according to the present invention.
【図3】本発明による偏光プリズムのさらに別の実施例
の平面概念図である。FIG. 3 is a conceptual plan view of still another embodiment of the polarizing prism according to the present invention.
【図4】本発明による偏光プリズムの1実施例の(A)
板状媒体の一方の面における透過分光特性、(B)板状
媒体の他方の面における透過分光特性、(C)偏光プリ
ズム総合の透過分光特性である。FIG. 4A shows an embodiment of a polarizing prism according to the present invention.
These are transmission spectral characteristics on one surface of the plate medium, (B) transmission spectral characteristics on the other surface of the plate medium, and (C) transmission spectral characteristics of the polarizing prism as a whole.
【図5】本発明による偏光プリズムの1実施例の(A)
板状媒体の一方の面における透過分光特性、(B)板状
媒体の他方の面における透過分光特性、(C)偏光プリ
ズム総合の透過分光特性である。FIG. 5A shows an embodiment of a polarizing prism according to the present invention.
These are transmission spectral characteristics on one surface of the plate medium, (B) transmission spectral characteristics on the other surface of the plate medium, and (C) transmission spectral characteristics of the polarizing prism as a whole.
【図6】本発明による偏光プリズムの1実施例の総合の
透過分光特性である。FIG. 6 is an overall transmission spectral characteristic of one embodiment of the polarizing prism according to the present invention.
【図7】本発明による偏光プリズムの1実施例の総合の
透過分光特性である。FIG. 7 is an overall transmission spectral characteristic of one embodiment of the polarizing prism according to the present invention.
【図8】本発明による反射型光変調プロジェクタの1実
施例の光学系の概念図である。FIG. 8 is a conceptual diagram of an optical system of one embodiment of a reflection type light modulation projector according to the present invention.
【図9】本発明による反射型光変調プロジェクタの他の
実施例の光学系の概念図である。FIG. 9 is a conceptual diagram of an optical system of another embodiment of the reflection type light modulation projector according to the present invention.
【図10】従来の反射型光変調プロジェクタの1例の光
学系の概念図である。FIG. 10 is a conceptual diagram of an optical system of an example of a conventional reflection type light modulation projector.
1 偏光プリズム 1a、1c 三角柱 1b 薄板ガラス 2 四角柱 2b 液体 3 四角柱 3b 薄板ガラス Lp P偏光光 Ls S偏光光 B 青色光 G 緑色光 R 赤色光 T 透過率 81 光源 82 ポラライザ 83 ダイクロイックミラー 84 PBS(偏光ビームスプリッタ) 85r、85g、85b 偏光変調素子 86 偏光プリズム 87 ダイクロイックミラー 88 投写レンズ 93 偏光プリズム 94 PBS 101、102、104、105 ダイクロイックミラ
ー 103r、103g、103b PBS 108 投写レンズDESCRIPTION OF SYMBOLS 1 Polarizing prism 1a, 1c Triangular prism 1b Thin glass 2 Square prism 2b Liquid 3 Square prism 3b Thin glass Lp P polarized light Ls S polarized light B Blue light G Green light R Red light T Transmittance 81 Light source 82 Polarizer 83 Dichroic mirror 84 PBS (Polarizing beam splitter) 85r, 85g, 85b Polarization modulating element 86 Polarizing prism 87 Dichroic mirror 88 Projection lens 93 Polarizing prism 94 PBS 101, 102, 104, 105 Dichroic mirror 103r, 103g, 103b PBS 108 Projection lens
フロントページの続き (51)Int.Cl.6 識別記号 FI H04N 9/31 H04N 9/31 C Continued on the front page (51) Int.Cl. 6 Identification code FI H04N 9/31 H04N 9/31 C
Claims (16)
学薄膜を形成して分光特性をもたせた偏光ビームスプリ
ッタ機能を備えた偏光プリズムにおいて、張り合わせ面
に両面相互間の光学的干渉を回避するに足る厚さの平行
平面を有する板状透明媒体を介在させ、同板状透明媒体
の一方の面と前記一方の三角柱透明媒体との間に一方の
偏光光を透過しこれと直交する他方の偏光光に対して分
光特性を備えて反射又は透過する光学薄膜を形成し、同
板状透明媒体の他方の面と前記他方の三角柱透明媒体と
の間に前記他方の偏光光を透過し前記一方の偏光光に対
して分光特性を備えて反射又は透過する光学薄膜を形成
し、前記一方の偏光光及びこれと前記直交する他方の偏
光光に対して相互に独立した分光特性もつ偏光ビームス
プリッタ機能を備えたことを特徴とする偏光プリズム。In a polarizing prism having a polarizing beam splitter function in which an optical thin film is formed on a bonding surface of two triangular prism transparent media and having spectral characteristics, it is possible to avoid optical interference between both surfaces on the bonding surface. A plate-shaped transparent medium having a parallel plane with a sufficient thickness is interposed, and one polarized light beam is transmitted between one surface of the plate-shaped transparent medium and the one triangular prism transparent medium, and the other polarized light is orthogonal to this. Forming an optical thin film that reflects or transmits light with spectral characteristics, transmits the other polarized light between the other surface of the same plate-shaped transparent medium and the other triangular prism transparent medium, and transmits the other polarized light. Forming an optical thin film that reflects or transmits polarized light with spectral characteristics, and has a polarizing beam splitter function having spectral characteristics independent of each other for the one polarized light and the other orthogonal polarized light. Preparation A polarizing prism.
同質の光学ガラスから構成することを特徴とした請求項
1記載の偏光プリズム。2. The polarizing prism according to claim 1, wherein the triangular prism transparent medium and the plate-shaped medium are made of optical glass of substantially the same quality.
り抜いた光学ガラスからなり、同くり抜き部分の光学ガ
ラスの両面に前記光学薄膜を形成し、前記板状媒体は、
同くり抜き部分に充填した同光学ガラスと略同一屈折率
の液体とすることを特徴とした請求項1記載の偏光プリ
ズム。3. The triangular prism medium is made of optical glass obtained by hollowing out the plate-shaped medium portion, and the optical thin film is formed on both surfaces of the optical glass in the hollowed-out portion.
2. The polarizing prism according to claim 1, wherein the liquid is a liquid having substantially the same refractive index as the optical glass filled in the hollow portion.
体からなる四角柱と、両面に前記光学薄膜を形成した前
記板状媒体で同四角柱の中空部内の対角を結んで分割し
て2つの中空三角柱とし、同2つの中空三角柱の各中空
部に板状媒体と略同一屈折率の液体を充填して構成する
ことを特徴とした請求項1記載の偏光プリズム。4. The two triangular prism media are divided by connecting a diagonal in a hollow portion of the quadrangular prism with a quadrangular prism formed of a hollow transparent medium and the plate-shaped medium having the optical thin film formed on both surfaces thereof. 2. The polarizing prism according to claim 1, wherein the hollow prisms are two hollow triangular prisms, and each hollow portion of the two hollow triangular prisms is filled with a liquid having substantially the same refractive index as the plate-shaped medium.
角柱透明媒体との間の光学薄膜は、P偏光光を透過し所
定波長以上のS偏光光を透過し所定波長以下のS偏光光
を反射する特性を備え、板状透明媒体の他方の面と他方
の三角柱透明媒体との間の光学薄膜は、S偏光光を透過
し所定波長以下のP偏光光を透過し所定波長以上のP偏
光光を反射する特性を備えることを特徴とした請求項1
記載の偏光プリズム。5. An optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits P-polarized light, transmits S-polarized light of a predetermined wavelength or more, and S-polarized light of a predetermined wavelength or less. With the property of reflecting light, the optical thin film between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium transmits S-polarized light, transmits P-polarized light of a predetermined wavelength or less, and transmits light of a predetermined wavelength or more. 2. The device according to claim 1, wherein the device has a property of reflecting P-polarized light.
The polarizing prism as described.
角柱透明媒体との間の光学薄膜は、S偏光光を透過し所
定波長以上のP偏光光を透過し所定波長以下のP偏光光
を反射する特性を備え、板状透明媒体の他方の面と他方
の三角柱透明媒体との間の光学薄膜は、P偏光光を透過
し所定波長以下のS偏光光を透過し所定の波長以上のS
偏光光を反射する特性を備えることを特徴とした請求項
1記載の偏光プリズム。6. An optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits S-polarized light, transmits P-polarized light of a predetermined wavelength or more, and P-polarized light of a predetermined wavelength or less. With the property of reflecting light, the optical thin film between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium transmits P-polarized light and transmits S-polarized light having a predetermined wavelength or less and transmits a predetermined wavelength or more. S
2. The polarizing prism according to claim 1, wherein the polarizing prism has a characteristic of reflecting polarized light.
角柱透明媒体との間の光学薄膜は、P偏光光の白色光
(W)を透過しS偏光光の緑及び赤色光(Y)を透過し
青色光(B)を反射する特性を備え、板状透明媒体の他
方の面と他方の三角柱透明媒体との間の光学薄膜は、S
偏光光の白色光(W)を透過しP偏光光の青色光(B)
を透過し緑及び青色光(Y)を反射する特性を備えるこ
とを特徴とした請求項5記載の偏光プリズム。7. An optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits P-polarized light white light (W) and S-polarized light green and red light (Y ) And reflects the blue light (B), and the optical thin film between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium is S
Transmits white light (W) of polarized light and blue light (B) of P-polarized light
The polarizing prism according to claim 5, wherein the polarizing prism has a characteristic of transmitting green light and reflecting green and blue light (Y).
角柱透明媒体との間の光学薄膜は、S偏光光の白色光
(W)を透過しP偏光光の緑及び赤色光(Y)を透過し
青色光(B)を反射する特性を備え、板状透明媒体の他
方の面と他方の三角柱透明媒体との間の光学薄膜は、P
偏光光の白色光(W)を透過しS偏光光の青色光(B)
を透過し緑及び青色光(Y)を反射する特性を備えるこ
とを特徴とした請求項6記載の偏光プリズム。8. An optical thin film between one surface of said plate-shaped transparent medium and one triangular prism transparent medium transmits S-polarized light white light (W) and P-polarized light green and red light (Y ) And reflects the blue light (B), and the optical thin film between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium is P
S-polarized blue light (B) that transmits polarized white light (W)
7. The polarizing prism according to claim 6, wherein the polarizing prism has a characteristic of transmitting green light and reflecting green and blue light (Y).
角柱透明媒体との間の光学薄膜は、P偏光光の白色光
(W)を透過しS偏光光の赤色光(R)を透過し青及び
緑色光(C)を反射する特性を備え、板状透明媒体の他
方の面と他方の三角柱透明媒体との間の光学薄膜は、S
偏光光の白色光(W)を透過しP偏光光の青及び緑色光
(C)を透過し赤色光(R)を反射する特性を備えるこ
とを特徴とした請求項5記載の偏光プリズム。9. An optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits P-polarized light white light (W) and S-polarized light red light (R). It has the property of transmitting and reflecting blue and green light (C), and the optical thin film between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium is S
The polarizing prism according to claim 5, wherein the polarizing prism has a characteristic of transmitting white light (W) of polarized light, transmitting blue and green light (C) of P-polarized light, and reflecting red light (R).
三角柱透明媒体との間の光学薄膜は、S偏光光の白色光
(W)を透過しP偏光光の赤色光(R)を透過し青及び
緑色光(C)を反射する特性を備え、板状透明媒体の他
方の面と他方の三角柱透明媒体との間の光学薄膜は、P
偏光光の白色光(W)を透過しS偏光光の青及び緑色光
(C)を透過し赤色光(R)を反射する特性を備えるこ
とを特徴とした請求項6記載の偏光プリズム。10. An optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits white light (W) of S-polarized light and transmits red light (R) of P-polarized light. With the property of transmitting and reflecting blue and green light (C), the optical thin film between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium has P
7. The polarizing prism according to claim 6, wherein the polarizing prism has a characteristic of transmitting white light (W) of polarized light, transmitting blue and green light (C) of S-polarized light, and reflecting red light (R).
三角柱透明媒体との間の光学薄膜は、P偏光光の白色光
(W)を透過しS偏光光の赤色光(R)を透過し青色光
(B)を反射する特性を備え、板状透明媒体の他方の面
と他方の三角柱透明媒体との間の光学薄膜は、S偏光光
の白色光(W)を透過しP偏光光の青色光(B)を透過
し赤色光(R)を反射する特性を備えることを特徴とし
た請求項5記載の偏光プリズム。11. An optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits P-polarized light white light (W) and transmits S-polarized light red light (R). It has the property of transmitting and reflecting blue light (B), and the optical thin film between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium transmits S-polarized light white light (W) and P-polarized light. The polarizing prism according to claim 5, wherein the polarizing prism has a characteristic of transmitting blue light (B) and reflecting red light (R).
三角柱透明媒体との間の光学薄膜は、S偏光光の白色光
(W)を透過しP偏光光の赤色光(R)を透過し青色光
(B)を反射する特性を備え、板状透明媒体の他方の面
と他方の三角柱透明媒体との間の光学薄膜は、P偏光光
の白色光(W)を透過しS偏光光の青色光(B)を透過
し赤色光(R)を反射する特性を備えることを特徴とし
た請求項6記載の偏光プリズム。12. An optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits white light (W) of S-polarized light and transmits red light (R) of P-polarized light. It has the property of transmitting and reflecting blue light (B), and the optical thin film between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium transmits P-polarized light white light (W) and S-polarized light. The polarizing prism according to claim 6, wherein the polarizing prism has a characteristic of transmitting blue light (B) and reflecting red light (R).
三角柱透明媒体との間の光学薄膜は、P偏光光の白色光
(W)を透過しS偏光光の青色光及び赤色光(M)を透
過し緑色光(G)を反射する特性を備え、板状透明媒体
の他方の面と他方の三角柱透明媒体との間の光学薄膜
は、S偏光光の白色光(W)を透過しP偏光光の緑色光
(G)を透過し青色光及び赤色光(M)を反射する特性
を備えることを特徴とした請求項1記載の偏光プリズ
ム。13. An optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits P-polarized light white light (W) and S-polarized light blue light and red light (W). M) and has a characteristic of reflecting green light (G), and the optical thin film between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium transmits white light (W) of S-polarized light. 2. The polarizing prism according to claim 1, wherein the polarizing prism has a characteristic of transmitting green light (G) of P-polarized light and reflecting blue light and red light (M).
三角柱透明媒体との間の光学薄膜は、S偏光光の白色光
(W)を透過しP偏光光の青色光及び赤色光(M)を透
過し緑色光(G)を反射する特性を備え、板状透明媒体
の他方の面と他方の三角柱透明媒体との間の光学薄膜
は、P偏光光の白色光(W)を透過しS偏光光の緑色光
(G)を透過し青色光及び赤色光(M)を反射する特性
を備えることを特徴とした請求項1記載の偏光プリズ
ム。14. An optical thin film between one surface of the plate-shaped transparent medium and one triangular prism transparent medium transmits S-polarized light white light (W) and P-polarized light blue light and red light (W). M) and transmits green light (G), and the optical thin film between the other surface of the plate-shaped transparent medium and the other triangular prism transparent medium transmits white light (W) of P-polarized light. 2. The polarizing prism according to claim 1, wherein the polarizing prism has a characteristic of transmitting green light (G) of S-polarized light and reflecting blue light and red light (M).
リズムの組合せにより光源からの光線を変調して投写レ
ンズでスクリーン上に投写してカラーの映像を表示する
反射型光変調プロジェクタにおいて、前記光源からの光
線をP偏光とするポラライザと、同P偏光の内の緑色光
線を反射し青及び赤色光線を透過するダイクロイックミ
ラーと、同反射した緑色光線のP偏光光を反射しS偏光
光を透過する偏光ビームスプリッタ(以下PBSとい
う)と、同PBSで反射したP偏光の緑色光線を受け偏
光変調して反射し同PBSに再入射する緑用の偏光変調
素子と、前記ダイクロイックミラーを透過する青色光線
及び赤色光線の内青色光線のP偏光光を反射しS偏光光
を透過し赤色光線のP偏光光を透過しS偏光光を反射す
る偏光プリズムと、同偏光プリズムで反射する青色光線
のP偏光光を受け偏光変調して反射して同偏光プリズム
に再入射する青用の偏光変調素子と、同偏光プリズムを
透過する赤色光線のP偏光光を受けて偏光変調して反射
して同偏光プリズムに再入射する赤用の偏光変調素子
と、同偏光プリズムで同プリズムに再入射した青色光線
のS偏光光を透過して検光し赤色光線のS偏光光を反射
して検光し、前記PBSに再入射する緑色光線を同PB
Sで検光して出射し、前記プリズムから出射する青及び
赤色光を透過し前記PBSから出射する緑色光を反射す
るダイクロイックミラーと、同ダイクロイックミラーか
ら出射する青、赤及び緑色光線を入射して投写する投写
レンズを備えたことを特徴とした反射型光変調プロジェ
クタ。15. A reflection type light modulation projector for displaying a color image by modulating a light beam from a light source by a combination of a plurality of reflection type polarization modulation elements and a polarization prism and projecting the light beam on a screen by a projection lens. A polarizer that converts the light from the light source into P-polarized light, a dichroic mirror that reflects green light of the same P-polarized light and transmits blue and red light, and reflects P-polarized light of the reflected green light and converts S-polarized light into A polarizing beam splitter (hereinafter referred to as a PBS) that transmits, a P-polarized green light reflected by the PBS, polarization-modulated and reflected and reflected again by the PBS, and transmitted through the dichroic mirror. A polarizing prism that reflects P-polarized light of blue light, transmits S-polarized light, transmits P-polarized light of red light, and reflects S-polarized light; Receiving P-polarized light of blue light reflected by the polarizing prism, polarization-modulating the reflected light, reflecting it, and re-entering the same polarizing prism, and receiving P-polarized light of red light transmitted through the same polarizing prism. A polarization modulator for red, which is polarized and reflected and re-enters the same polarizing prism, and an S-polarized red light which is analyzed by transmitting S-polarized light of blue light re-entered by the same polarizing prism. The light is reflected and analyzed, and the green light re-entering the PBS is reflected by the PB.
A dichroic mirror that detects and emits light at S, transmits blue and red light emitted from the prism, and reflects green light emitted from the PBS, and receives blue, red, and green light emitted from the dichroic mirror. A reflection-type light modulation projector comprising a projection lens for projecting light.
リズムの組合せにより光源からの光線を変調して投写レ
ンズでスクリーン上に投写してカラーの映像を表示する
反射型光変調プロジェクタにおいて、前記光源からの光
線の内のP偏光光の青色光線及び赤色光線を透過しS偏
光光の緑色光線を反射する第一の偏光プリズムと、同偏
光プリズムで反射する緑色光線の内S偏光を透過しP偏
光光を反射するPBSと、同PBSを透過するS偏光光
を受け偏光変調して反射し同PBSに再入射する緑用の
偏光変調素子と、前記第一の偏光プリズムを透過するP
偏光の内青色光線を反射し青色光線のS偏光光を透過し
赤色光線を透過し赤色光線のP偏光光を反射する第二の
偏光プリズムと、同偏光プリズムで反射する青色光線の
P偏光光を受け偏光変調して反射して同偏光プリズムに
再入射する青用の偏光変調素子と、同偏光プリズムを透
過する赤色光線のP偏光光を受け偏光変調して反射して
同偏光プリズムに再入射する赤用の偏光変調素子と、同
偏光プリズムに再入射した青色光線を検光しS偏光光を
透過し赤色光線を検光してS偏光光を反射して出射し、
前記PBSに再入射する緑色光線を反射して検光しP偏
光光を出射し、これら出射する青及び赤色光線を透過し
緑色光線を反射するダイクロイックミラーと、同ダイク
ロイックミラーから出射する青、赤及び緑色光線を入射
して投写する投写レンズを備えたことを特徴とした反射
型光変調プロジェクタ。16. A reflection-type light modulation projector that modulates a light beam from a light source by a combination of a plurality of reflection-type polarization modulation elements and a polarization prism and projects the color image on a screen by a projection lens to display a color image. A first polarizing prism that transmits blue light and red light of P-polarized light and reflects green light of S-polarized light among the light from the light source, and transmits S-polarized light of green light reflected by the same polarizing prism. PBS that reflects P-polarized light, S-polarized light that passes through the PBS, receives polarization-modulated light, reflects the polarization, and re-enters the PBS. A green polarization modulation element, and P that transmits through the first polarizing prism.
Among the polarized light, a second polarizing prism that reflects blue light, transmits S-polarized light of blue light, transmits red light, and reflects P-polarized light of red light, and P-polarized light of blue light reflected by the same polarizing prism The polarization modulator for blue, which receives and modulates the polarized light, reflects the reflected light, and re-enters the same polarizing prism, and receives the P-polarized light of the red light transmitted through the same polarizing prism, modulates the polarized light, reflects the reflected light, and re-enters the same polarizing prism. The incident polarization modulator for red and the blue light re-entered into the same polarizing prism are analyzed, the S-polarized light is transmitted, the red light is analyzed, and the S-polarized light is reflected and emitted,
The dichroic mirror reflects the green light re-entering the PBS, detects and emits P-polarized light, transmits the emitted blue and red light, and reflects the green light, and blue and red emitted from the dichroic mirror. And a projection lens for projecting and projecting a green light ray.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP10008352A JPH11202132A (en) | 1998-01-20 | 1998-01-20 | Polarizing prism and reflection type optical modulating projector |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP10008352A JPH11202132A (en) | 1998-01-20 | 1998-01-20 | Polarizing prism and reflection type optical modulating projector |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH11202132A true JPH11202132A (en) | 1999-07-30 |
Family
ID=11690842
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP10008352A Pending JPH11202132A (en) | 1998-01-20 | 1998-01-20 | Polarizing prism and reflection type optical modulating projector |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH11202132A (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2001023920A1 (en) * | 1999-09-29 | 2001-04-05 | Fujitsu General Limited | Polarized light spectroscopic device and picture projector comprising the polarized light spectroscopic device |
JP2002107664A (en) * | 2000-09-21 | 2002-04-10 | Samsung Electronics Co Ltd | Image projecting device |
WO2003001277A1 (en) * | 2001-06-22 | 2003-01-03 | Seiko Epson Corporation | Illumination optical system and projector |
JP2005250057A (en) * | 2004-03-03 | 2005-09-15 | Hitachi Ltd | Projection type video display device, optical unit to be used for the same and structure for separating polarized light |
JP2006133802A (en) * | 1999-09-17 | 2006-05-25 | Hitachi Ltd | Video display device |
KR100611211B1 (en) * | 2001-04-09 | 2006-08-09 | 삼성에스디아이 주식회사 | Optical Apparatus of Projection System |
JP2007115300A (en) * | 2005-10-18 | 2007-05-10 | Konica Minolta Opto Inc | Optical element, optical pickup device, and manufacturing method of optical element |
-
1998
- 1998-01-20 JP JP10008352A patent/JPH11202132A/en active Pending
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006133802A (en) * | 1999-09-17 | 2006-05-25 | Hitachi Ltd | Video display device |
WO2001023920A1 (en) * | 1999-09-29 | 2001-04-05 | Fujitsu General Limited | Polarized light spectroscopic device and picture projector comprising the polarized light spectroscopic device |
JP2002107664A (en) * | 2000-09-21 | 2002-04-10 | Samsung Electronics Co Ltd | Image projecting device |
KR100611211B1 (en) * | 2001-04-09 | 2006-08-09 | 삼성에스디아이 주식회사 | Optical Apparatus of Projection System |
WO2003001277A1 (en) * | 2001-06-22 | 2003-01-03 | Seiko Epson Corporation | Illumination optical system and projector |
US6739724B2 (en) | 2001-06-22 | 2004-05-25 | Seiko Epson Corporation | Illumination optical system and projector |
JP2005250057A (en) * | 2004-03-03 | 2005-09-15 | Hitachi Ltd | Projection type video display device, optical unit to be used for the same and structure for separating polarized light |
JP4575682B2 (en) * | 2004-03-03 | 2010-11-04 | 株式会社日立製作所 | Projection-type image display device and polarization separation structure |
JP2007115300A (en) * | 2005-10-18 | 2007-05-10 | Konica Minolta Opto Inc | Optical element, optical pickup device, and manufacturing method of optical element |
JP4561586B2 (en) * | 2005-10-18 | 2010-10-13 | コニカミノルタオプト株式会社 | Optical element manufacturing method |
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