JPH05150361A - Projection type display device - Google Patents
Projection type display deviceInfo
- Publication number
- JPH05150361A JPH05150361A JP3314859A JP31485991A JPH05150361A JP H05150361 A JPH05150361 A JP H05150361A JP 3314859 A JP3314859 A JP 3314859A JP 31485991 A JP31485991 A JP 31485991A JP H05150361 A JPH05150361 A JP H05150361A
- Authority
- JP
- Japan
- Prior art keywords
- projection
- light
- beam splitter
- polarization beam
- display device
- 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.)
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、投射型表示装置に関
し、特に、従来装置よりも簡易な構成の自動合焦光学系
を有した投射型表示装置に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection type display device, and more particularly to a projection type display device having an automatic focusing optical system having a simpler structure than conventional devices.
【０００２】[0002]
【従来の技術】従来、スライドプロジェクター等の投射
型表示装置が知られているが、近年投射原画を液晶等の
ライトバルブで構成する投射型表示装置も出現してい
る。2. Description of the Related Art Conventionally, a projection type display device such as a slide projector has been known, but in recent years, a projection type display device in which a projection original image is composed of a light valve such as a liquid crystal has also appeared.
【０００３】これらの投射型表示装置に於て、ピント合
わせの煩わしさから開放するために投射型表示装置の外
部に焦点検出器を設け、自動的に合焦動作を行なうもの
も知られている。Among these projection type display devices, there is also known one in which a focus detector is provided outside the projection type display device to perform focusing operation automatically in order to free the trouble of focusing. ..
【０００４】[0004]
【発明が解決しようとする課題】しかしながら上記従来
例の自動合焦点装置付きの投射型表示装置に於ては、焦
点検出措置と撮影レンズが別光学系であるので、光源の
熱等で投射レンズの屈折率変化が生じてピント移動が起
きたときに焦点検出装置が対応できないという問題点が
あった。However, in the projection type display device with the automatic focusing device of the above-mentioned conventional example, since the focus detection means and the photographing lens are separate optical systems, the projection lens is caused by the heat of the light source or the like. However, there is a problem that the focus detection device cannot cope with the case where the change in the refractive index occurs and the focus movement occurs.
【０００５】投射レンズを通過した光束で焦点検出を行
なうＴＴＬ−ＡＦにすれば上記問題点は解決するが、そ
のような構成にした場合は投射原画を投射する光路中に
焦点検出装置へ光を導くビームスプリッターを投射原画
の投射中も常時設けておかなければならないため投射画
像の明るさを低減する恐れがある、という別の問題点が
生じてくる。The above problem can be solved by using the TTL-AF for detecting the focus by the light flux that has passed through the projection lens. However, in the case of such a configuration, the light is sent to the focus detecting device in the optical path for projecting the original projection image. Another problem arises in that the guiding beam splitter must be always provided even during the projection of the projection original image, which may reduce the brightness of the projection image.
【０００６】従って、本発明の目的は、前記問題点を解
決できる、改良された投射型表示装置を提供することで
ある。Accordingly, it is an object of the present invention to provide an improved projection type display device which can solve the above problems.
【０００７】[0007]
【課題を解決するための手段】本発明は、投射原画を投
射光源及び投射レンズで被投射面に投射し、該被投射面
からの反射光を該投射レンズで受け、該投射レンズの内
部或いは該投射レンズと該投射原画の間に設けられたビ
ームスプリッターで合焦点検出装置の受光部へ導き合焦
点検出を行なう投射型表示装置に於て、ビームスプリッ
ターを偏光ビームスプリッターで構成したことにより、
投射画像の明るさを損なわずにＴＴＬの自動合焦点装置
を投射型表示装置に採用することを可能にしたものであ
る。According to the present invention, a projection original image is projected onto a projection surface by a projection light source and a projection lens, and reflected light from the projection surface is received by the projection lens. In the projection type display device which performs the focus detection by guiding the light to the light receiving portion of the focus detection device by the beam splitter provided between the projection lens and the projection original image, by configuring the beam splitter with a polarization beam splitter,
The TTL automatic focusing device can be adopted for a projection type display device without impairing the brightness of the projected image.
【０００８】[0008]
【実施例】図１は本発明の第１の実施例であり、ハロゲ
ンランプ或はメタルハライドランプの様な投射光源１、
リフレクター２、投射原画の熱損傷を防ぐために熱線を
カットする熱線カットフィルター３、液晶ライトバルブ
の投射原画４、液晶ライトバルブ４の両側に偏光軸が直
交する関係に設置されている偏光板４１及び４２、偏光
分離膜５−１を設けた偏光ビームスプリッター５、スク
リーン７に投射原画４を投射する投射レンズ６、焦点検
出器８、レンズ駆動装置９、で構成されており、投射光
源１の光は熱線カットフィルター３で熱線がカットされ
て投射原画４を照明する。投射原画４を透過し、紙面に
平行な方向に偏光軸を有する偏光板４１及び４２を通過
した光（Ｐ偏光）は偏光ビームスプリッター５に入射
し、該偏光ビームスプリッター５を殆ど影響なく透過
し、投射レンズ６でスクリーン７上に投射される。スク
リーン７で拡散反射された光は多少偏光が崩れてＳ偏光
成分も含んでいるので、投射レンズ６を透過し、再び偏
光ビームスプリッター５に入射するとＳ偏光は偏光ビー
ムスプリッター５で反射して焦点検出器８へ導かれて焦
点検出が行なわれる。更に、焦点検出器８の出力信号に
従ってレンズ駆動装置９で投射レンズ６を駆動し、ピン
ト合わせが行なわれる。FIG. 1 is a first embodiment of the present invention, which is a projection light source 1 such as a halogen lamp or a metal halide lamp.
A reflector 2, a heat ray cut filter 3 that cuts heat rays to prevent heat damage to the projection original image, a projection original image 4 of the liquid crystal light valve, a polarizing plate 41 installed on both sides of the liquid crystal light valve 4 in a relationship in which polarization axes are orthogonal to each other, and 42, a polarization beam splitter 5 provided with a polarization separation film 5-1, a projection lens 6 that projects the projection original image 4 on a screen 7, a focus detector 8, and a lens driving device 9, and the light from the projection light source 1 The heat ray is cut by the heat ray cut filter 3 to illuminate the projection original image 4. The light (P-polarized light) that has passed through the projection original image 4 and passed through the polarizing plates 41 and 42 having the polarization axis in the direction parallel to the paper surface enters the polarization beam splitter 5 and is transmitted through the polarization beam splitter 5 with almost no effect. Is projected on the screen 7 by the projection lens 6. The light diffusely reflected by the screen 7 is slightly depolarized and also contains S-polarized light components. Therefore, when the light passes through the projection lens 6 and enters the polarization beam splitter 5 again, the S-polarized light is reflected by the polarization beam splitter 5 and focused. The focus is guided to the detector 8 for focus detection. Furthermore, the lens driving device 9 drives the projection lens 6 in accordance with the output signal of the focus detector 8 to perform focusing.
【０００９】なお、焦点検出器８としては、画像のボケ
を検出する方式の従来知られている焦点検出法によるも
のを使用しても良いし、瞳分割の光学系を用いて２像の
ズレを検知して焦点を検出する従来知られている焦点検
出法によるものを使用しても良い。As the focus detector 8, a conventionally known focus detection method of detecting a blur of an image may be used. Alternatively, a pupil division optical system may be used to shift two images. It is also possible to use a conventionally known focus detection method for detecting the focus to detect the focus.
【００１０】従来、ＴＴＬ−ＡＦを投射型表示装置に採
用した場合は光を投射する光路中に焦点検出器へ光を導
くビームスプリッターが設けられているため投射画像が
暗くなってしまうという問題点があったが、本実施例の
光学系によれば投射光源１を投光光源とする自動合焦点
装置に於て投射画像の明るさを損なわずにＴＴＬ−ＡＦ
を投射型表示装置に採用することができる。投射型表示
装置でＴＴＬ−ＡＦにすると、投射レンズ６に対して投
射原画４と共役な位置に焦点検出器８の受光部を設置す
ればよく、一旦セットされた後には光源の熱等で投射レ
ンズの屈折率変化が生じてピント移動が起きたときやレ
ンズのガタがあるときにも自動合焦点装置と投射レンズ
のピントずれが生じないというメリットがある。Conventionally, when the TTL-AF is adopted in a projection type display device, a beam splitter for guiding light to a focus detector is provided in an optical path for projecting light, so that a projected image becomes dark. However, according to the optical system of the present embodiment, the TTL-AF does not impair the brightness of the projected image in the automatic focusing device using the projection light source 1 as the projection light source.
Can be used in a projection display device. When the TTL-AF is used in the projection type display device, the light receiving portion of the focus detector 8 may be installed at a position conjugate with the projection original image 4 with respect to the projection lens 6, and once set, projection is performed by heat of the light source or the like. There is an advantage that the automatic focusing device and the projection lens are not out of focus even when the refractive index of the lens is changed and the focus is moved or the lens is loose.
【００１１】本実施例に於ては、投射するときの投射レ
ンズにおける内面反射によるゴースト光が偏光ビームス
プリッター５に再入射してもＰ偏光なので偏光ビームス
プリッター５を透過してしまい、合焦点検出装置の受光
部へは入射しないので、検出光のＳＮ比がよく焦点検出
精度が高い。更に、偏光ビームスプリッター５を液晶パ
ネル方向へ透過した上記内面反射によるゴースト光は液
晶パネルの表面で反射して偏光ビームスプリッター５に
再度入射するが、Ｐ偏光なので再び偏光ビームスプリッ
ター５を透過して投射レンズを透過してしまい、やはり
合焦点検出装置の受光部へは入射しない。In the present embodiment, even if the ghost light due to the internal reflection in the projection lens at the time of projection is re-incident on the polarization beam splitter 5, since it is P-polarized light, it will pass through the polarization beam splitter 5 and focus detection will be performed. Since it does not enter the light receiving portion of the device, the SN ratio of the detection light is good and the focus detection accuracy is high. Further, the ghost light due to the above-mentioned internal reflection that has passed through the polarization beam splitter 5 toward the liquid crystal panel is reflected by the surface of the liquid crystal panel and re-enters the polarization beam splitter 5, but since it is P polarized light, it passes through the polarization beam splitter 5 again. The light passes through the projection lens and does not enter the light receiving portion of the focus detection device.
【００１２】さらに本実施例に於ては投射画像を投射す
る投射光源を利用して焦点検出を行なっているので、焦
点検出用の投光光源を別に持たなくてもよいので部品点
数が少なくてすむ。Further, in this embodiment, since the focus detection is performed by using the projection light source for projecting the projection image, it is not necessary to separately provide a light source for focus detection, so that the number of parts is small. I'm sorry.
【００１３】第２実施例 図２は本発明の第２実施例であり、前述した第１実施例
の熱線カットフィルター３と液晶板である投射原画４の
間に、三角プリズムと平行四辺形のプリズムを接合し、
接合面に偏光分離膜４４を設け、平行四辺形のプリズム
の射出部に１／２波長板４６を設けた偏光変換素子４３
を追加し、図１において液晶ライトバルブ４の両側に設
置されていた偏光板４１及び４２を廃止したものであ
る。Second Embodiment FIG. 2 shows a second embodiment of the present invention, in which a triangular prism and a parallelogram are provided between the heat ray cut filter 3 of the first embodiment and the projection original image 4 which is a liquid crystal plate. Join the prism,
A polarization conversion element 43 in which a polarization separation film 44 is provided on the joint surface, and a ½ wavelength plate 46 is provided on the exit portion of a parallelogram prism.
Is added, and the polarizing plates 41 and 42 installed on both sides of the liquid crystal light valve 4 in FIG. 1 are abolished.
【００１４】投射光源１の光はあらゆる方向に偏光方向
を持つ自然光であるが、熱線カットフィルター３で熱線
がカットされて偏光変換素子４３へ入射し、接合面の偏
光分離膜４４で、Ｐ偏光成分は透過して偏光変換素子４
３を射出し、Ｓ偏光成分は反射して平行四辺形のプリズ
ムの全反射面４５でＰ偏光成分と同一進行方向に向けら
れ、さらに１／２波長板４６で偏光方向が９０度回転し
てＰ偏光として偏光変換素子４３を射出する。このよう
にして偏光変換素子４３は入射自然光をＰ偏光に揃えて
射出する。The light of the projection light source 1 is natural light having a polarization direction in all directions, but the heat rays are cut by the heat ray cut filter 3 and enter the polarization conversion element 43, and the polarized light separation film 44 on the bonding surface causes P polarization to occur. The component transmits and the polarization conversion element 4
3 is emitted, the S-polarized light component is reflected and directed in the same traveling direction as the P-polarized light component on the total reflection surface 45 of the parallelogram prism, and the polarization direction is rotated by 90 ° by the ½ wavelength plate 46. The polarization conversion element 43 is emitted as P-polarized light. In this way, the polarization conversion element 43 aligns incident natural light into P-polarized light and emits it.
【００１５】従って液晶ライトバルブ４の入射側の偏光
板は不要であり、一方射出側の偏光板も偏光ビームスプ
リッター５で代用できるため不要である。投射原画４を
透過した液晶で変調された光は偏光ビームスプリッター
５に入射し、該偏光ビームスプリッター５で検光され
て、投射レンズ６でスクリーン７に投射画像として投射
される。ここで、投射レンズ６のスクリーン側に１／４
波長板１４を設け、投射光を円偏光としている。このよ
うにするとスクリーン７で拡散反射され、投射レンズ６
を透過し、偏光ビームスプリッター５で反射して焦点検
出器８へ導かれるＳ偏光成分はスクリーンがどの様なも
のであっても５０％は確保されることになる。Therefore, the polarizing plate on the incident side of the liquid crystal light valve 4 is unnecessary, and the polarizing plate on the emitting side is also unnecessary because the polarizing beam splitter 5 can be substituted. The light transmitted through the projection original image 4 and modulated by the liquid crystal enters the polarization beam splitter 5, is detected by the polarization beam splitter 5, and is projected as a projection image on the screen 7 by the projection lens 6. Here, 1/4 on the screen side of the projection lens 6
A wave plate 14 is provided so that the projected light is circularly polarized light. In this way, the light is diffusely reflected by the screen 7 and the projection lens 6
50% of the S-polarized light component that is transmitted through, is reflected by the polarization beam splitter 5 and is guided to the focus detector 8 is secured regardless of the screen.
【００１６】本実施例では偏光ビームスプリッター５の
上部に黒色の平行平板の裏面に吸収塗料を塗布したゴー
スト光吸収板１２を傾斜して設けてあり、液晶で変調さ
れたＰ偏光以外の偏光成分も含む光が検光されて偏光ビ
ームスプリッター５に入射して反射したＳ偏光成分の光
を吸収することによって焦点検出精度をさらに高めるこ
とができる。In this embodiment, a ghost light absorbing plate 12 having a black parallel plate and a back surface coated with an absorbing paint is provided on the upper part of the polarization beam splitter 5 in an inclined manner, and a polarization component other than P polarized light modulated by liquid crystal is provided. The focus detection accuracy can be further improved by absorbing the light of the S-polarized component which is detected by the light including the light and is incident on the polarization beam splitter 5 and reflected.
【００１７】第３実施例 図３は本発明を３板式の液晶プロジェクターに適用した
第３実施例である。Third Embodiment FIG. 3 is a third embodiment in which the present invention is applied to a three-plate type liquid crystal projector.
【００１８】本実施例は、メタルハライドランプの投射
光源１、リフレクター２、熱線カットフィルター３、赤
色光と緑色光を透過し青色光を反射するダイクロイック
ミラー１０−１、緑色光を透過し赤色光反射するダイク
ロイックミラー１０−２、液晶ライトバルブで構成され
る投射原画４−１及び４−２並びに４−３、全反射ミラ
ー１３、接合面にＰ偏光を透過しＳ偏光を反射する偏光
分離膜５−１を設けた偏光ビームスプリッター５、投射
レンズ６、投射レンズ６で投射される投射原画４−１及
び４−２並びに４−３からの光束の球面収差の発生が同
一になる様にプリズムブロックとして接合面に青色光を
透過し赤色光を反射するダイクロイック膜１１−１−１
を設けたダイクロプリズム１１−１、青色光と赤色光を
透過し緑色光を反射するダイクロイックミラー１１−
２、焦点検出器８、で構成されている。In this embodiment, a projection light source 1 of a metal halide lamp, a reflector 2, a heat ray cut filter 3, a dichroic mirror 10-1 which transmits red light and green light and reflects blue light, and a green light which reflects red light. A dichroic mirror 10-2, projection original images 4-1 and 4-2 and 4-3 composed of liquid crystal light valves, a total reflection mirror 13, and a polarization splitting film 5 for transmitting P-polarized light and reflecting S-polarized light on a joint surface. The prism block so that the spherical aberrations of the light beams from the polarization beam splitter 5 provided with -1, the projection lens 6, and the projection original images 4-1 and 4-2 and 4-3 projected by the projection lens 6 are the same. Film that transmits blue light and reflects red light on the bonding surface
A dichroic prism 11-1, a dichroic mirror 11-1 that transmits blue light and red light and reflects green light.
2 and the focus detector 8.
【００１９】ここで液晶ライトバルブ４−１の投射レン
ズ側の偏光板射出光とビームスプリッター５の反射光は
Ｐ偏光となる様に配置されている。Here, the light emitted from the polarizing plate on the projection lens side of the liquid crystal light valve 4-1 and the reflected light from the beam splitter 5 are arranged to be P-polarized light.
【００２０】投射光源から発する光はダイクロイックミ
ラー１０−１及び１０−２でＲＧＢの３色の光に分解さ
れ、それぞれの色に対する画像情報を持つ液晶ライトバ
ルブの投射原画４−１及び４−２並びに４−３を透過し
て、再度ダイクロプリズム１１−１及びダイクロイック
ミラー１１−２でＲＧＢの３色の像が合成されて投射レ
ンズ６で不図示のスクリーン上に投射される。The light emitted from the projection light source is decomposed by the dichroic mirrors 10-1 and 10-2 into lights of three colors of RGB, and projection original images 4-1 and 4-2 of the liquid crystal light valve having image information for the respective colors. After passing through 4-3, the dichroic prism 11-1 and the dichroic mirror 11-2 again combine the images of the three colors RGB, and the projection lens 6 projects them on a screen (not shown).
【００２１】スクリーンからの拡散反射光はＳ偏光とＰ
偏光成分の混じった光であるが、投射レンズ６を透過
し、ダイクロイックミラー１１−２で反射し、偏光ビー
ムスプリッター５でＰ偏光成分は透過し焦点検出器８へ
と導かれて、焦点検出が行なわれる。The diffusely reflected light from the screen is S-polarized and P-polarized.
Although the light is a mixture of polarized light components, it passes through the projection lens 6, is reflected by the dichroic mirror 11-2, and the P polarized light component is transmitted by the polarization beam splitter 5 and is guided to the focus detector 8 for focus detection. Done.
【００２２】３板式の液晶プロジェクターに於ては投射
原画４−１及び４−２並びに４−３が液晶ライトバルブ
であり、その射出光が偏光であるため、この様に投射光
源１を投光光源とする自動合焦点装置によれば投射画像
の明るさを損なわずにＴＴＬ−ＡＦを投射型表示装置に
採用することができる。In the three-plate type liquid crystal projector, the projection original images 4-1 and 4-2 and 4-3 are liquid crystal light valves, and the emitted light thereof is polarized light. According to the automatic focusing device using the light source, the TTL-AF can be adopted in the projection type display device without impairing the brightness of the projected image.
【００２３】又、本実施例では投射原画４−１を射出し
た光をダイクロイックミラー１１−２の方向へ向かわせ
るミラーが焦点検出器８へ被投射面からの反射光を導く
ビームスプリッターを兼ねているので従来装置よりも構
造を簡単にすることができる。In the present embodiment, the mirror that directs the light emitted from the projection original image 4-1 toward the dichroic mirror 11-2 also serves as a beam splitter that guides the reflected light from the projection surface to the focus detector 8. Therefore, the structure can be simpler than that of the conventional device.
【００２４】更に、本発明では投射原画４−２と４−３
の光を合成する光学素子１１−１をダイクロプリズムと
したが、投射レンズ６のＦナンバーによってはダイクロ
イックミラーで構成しても３像の投射像のアンバランス
は無視することができる。Further, in the present invention, the projection original images 4-2 and 4-3
Although the optical element 11-1 which synthesizes the light is a dichroic prism, depending on the F number of the projection lens 6, even if the dichroic mirror is used, the imbalance of the three projected images can be ignored.
【００２５】なお、本発明の実施態様は上述の実施例に
限られるものではなく、以下のような実施態様も本発明
に包含されるものである。The embodiments of the present invention are not limited to the above-mentioned embodiments, and the following embodiments are also included in the present invention.
【００２６】（ａ）スライドプロジェクターの様に投射
原画を本装置から出し入れ可能なものは投射原画を挿入
部に挿入したときに本発明の構成をとるものと解釈す
る。(A) A device such as a slide projector that can put the projection original image in and out of the apparatus is interpreted as having the configuration of the present invention when the projection original image is inserted into the insertion portion.
【００２７】（ｂ）投射光学系の外部に焦点検出用の投
光光源及びチャートを設け、スクリーンからの拡散反射
光を投射レンズ６を透過し、ダイクロイックミラー１１
−２で反射し、偏光ビームスプリッター５でＰ偏光成分
は透過し、結像レンズ１５で焦点検出器８へと導いて焦
点検出を行なう様な構成も可能である。この時、外部の
焦点検出用の投光を、焦点検出装置８に導かれる偏光と
同じ偏光成分で行なうと光の損失及びゴースト光を小さ
くすることができる。(B) A projection light source for focus detection and a chart are provided outside the projection optical system, diffused reflected light from the screen is transmitted through the projection lens 6, and the dichroic mirror 11 is provided.
A configuration is also possible in which the light is reflected at -2, the P-polarized component is transmitted by the polarization beam splitter 5, and is guided to the focus detector 8 by the imaging lens 15 to perform focus detection. At this time, if the external projection light for focus detection is performed with the same polarization component as the polarization guided to the focus detection device 8, the loss of light and the ghost light can be reduced.
【００２８】（ｃ）偏光ビームスプリッター５はプリズ
ムの形だけでなく、平行平面板に偏光分離膜をコーティ
ングしたものでもよい。(C) The polarization beam splitter 5 is not limited to the prism shape, and may be a parallel plane plate coated with a polarization separation film.
【００２９】[0029]
【発明の効果】本発明の様な構成をとることにより投射
光が減衰することなく投射原画を投射できるので、投射
型表示装置とＴＴＬ−ＡＦとの組み合わせを実用的に可
能とすることができ、投射画像の明るさの低減なしに実
現することができる。これはまた、焦点検出用の光量も
多いことも意味しており、焦点検出精度を高めることが
できることを意味している。By adopting the structure of the present invention, the projection original image can be projected without attenuating the projection light, so that it is possible to practically combine the projection type display device and the TTL-AF. Can be realized without reducing the brightness of the projected image. This also means that there is a large amount of light for focus detection, which means that focus detection accuracy can be improved.
【００３０】なお、本発明に於ては投射型表示装置とＴ
ＴＬ−ＡＦとを組み合わせているので、一旦セットされ
た後には光源の熱等で投射レンズの屈折率変化が生じて
ピント移動が起きたときやレンズのガタがあるときにも
自動合焦点装置と投射レンズのピントずれが生じないと
いう利点がある。In the present invention, the projection type display device and the T
Since it is combined with TL-AF, it can be used as an automatic focusing device even when the focus lens moves due to a change in the refractive index of the projection lens due to the heat of the light source, etc. after it is once set. There is an advantage in that the projection lens is not out of focus.
【００３１】また、投射光源及び投射レンズによって被
投射面に投射された投射原画の反射光を投射レンズで受
けたのち合焦点検出装置の受光部へ導き合焦点検出を行
なう方式の場合、投射するときの投射レンズに於ける内
面反射で偏光ビームスプリッターに再入射するゴースト
光が合焦点検出装置の受光部へ入射することがないの
で、検出光のＳＮ比がよく焦点検出精度が高い。Further, in the case of a system in which the reflected light of the projection original image projected on the projection surface by the projection light source and the projection lens is received by the projection lens and then guided to the light receiving section of the focus detection device, the focus is detected. Since the ghost light that re-enters the polarization beam splitter due to the internal reflection at the projection lens does not enter the light receiving portion of the focus detection device, the SN ratio of the detection light is good and the focus detection accuracy is high.
【図１】本発明の第１実施例の光学系の概略図。FIG. 1 is a schematic diagram of an optical system according to a first embodiment of the present invention.
【図２】本発明の第２実施例の光学系の概略図。FIG. 2 is a schematic diagram of an optical system according to a second embodiment of the present invention.
【図３】３板式の液晶プロジェクターに本発明を適用し
た第３実施例の概略図。FIG. 3 is a schematic diagram of a third embodiment in which the present invention is applied to a three-plate type liquid crystal projector.
１…投射光源 ２…リフレクター ３…熱線カットフィルター ４、及び４−１、４−２、４−３…投射原画 ５…偏光ビームスプリッター ５−１…偏光分離膜 ６…投射レンズ ７…スクリーン ８…焦点検出器 ９…レンズ駆動装置 １０−１、１０−２、１１−２…ダイクロイックミラー １１−１…ダイクロイックプリズム １１−１−１…ダ イクロ膜 １２…ゴースト光吸収板 １３…全反射ミラ ー １４…１／４波長板 ４１及び４２…偏 光板 ４３…偏光変換素子 ４４…偏光分離膜 ４５…全反射部 ４６…１／４波長 板 DESCRIPTION OF SYMBOLS 1 ... Projection light source 2 ... Reflector 3 ... Heat ray cut filter 4, and 4-1, 4-2, 4-3 ... Projection original image 5 ... Polarization beam splitter 5-1 ... Polarization separation film 6 ... Projection lens 7 ... Screen 8 ... Focus detector 9 ... Lens driving device 10-1, 10-2, 11-2 ... Dichroic mirror 11-1 ... Dichroic prism 11-1-1 ... Dichroic film 12 ... Ghost light absorbing plate 13 ... Total reflection mirror 14 ... 1/4 wavelength plate 41 and 42 ... Polarizing plate 43 ... Polarization conversion element 44 ... Polarization separation film 45 ... Total reflection part 46 ... 1/4 wavelength plate
Claims (6)
投射面に投射し、該投射面からの反射光を該投射レンズ
で受け、該投射レンズの内部或いは該投射レンズと該投
射原画の間に設けられたビームスプリッターで合焦受光
部へ導き合焦検出を行なう投射型表示装置に於て、該ビ
ームスプリッターを偏光ビームスプリッターで構成した
ことを特徴とする投射型表示装置。1. A projection original image is projected onto a projection surface by a projection light source and a projection lens, and reflected light from the projection surface is received by the projection lens, and inside the projection lens or between the projection lens and the projection original image. A projection type display device for guiding focus to a focus light receiving section by a beam splitter provided in the above, wherein the beam splitter is a polarization beam splitter.
被投射面に投射された該投射原画の反射光を該合焦点検
出の受光部へ導き合焦点検出を行なうように構成したこ
とを特徴とする請求項１に記載の投射型表示装置。2. The focus light source is configured to guide reflected light of the projection original image projected on the projection surface by the projection light source and the projection lens to a light receiving section for the focus point detection. The projection display device according to claim 1.
該偏光ビームスプリッターで遮断されない方向の偏光で
あるように該偏光ビームスプリッターより投射光源側の
光学要素を定めたことを特徴とする請求項１に記載の投
射型表示装置。3. The optical element on the projection light source side of the polarization beam splitter is determined so that the light incident on the polarization beam splitter is polarized light in a direction not blocked by the polarization beam splitter. The projection type display device described in.
とする請求項１に記載の投射型表示装置。4. The projection type display device according to claim 1, wherein the projection original image is composed of liquid crystal.
分解し、分解した色光と同数の投射原画に導き、更に色
合成系で上記複数色の像を合成して投射レンズで投射す
る投射型表示装置に於て、該投射レンズの内部或いは該
投射レンズと該投射原画の間に、合焦点検出装置の受光
部へ光を導く偏光ビームスプリッターを設けたことを特
徴とする投射型表示装置。5. The light of a projection light source is separated into a plurality of color lights by a color separation system, and the same number of projection original images as the separated color lights are led, and then the plurality of color images are combined by a color combining system and projected by a projection lens. In the projection display device, a polarization beam splitter for guiding light to a light receiving portion of the focus detection device is provided inside the projection lens or between the projection lens and the projection original image. Display device.
れ、該投射原画を射出した光を反射するだけで色合成に
関与しない反射部材を、偏光ビームスプリッターで構成
したことを特徴とする請求項５に記載の投射型表示装
置。6. A polarizing beam splitter is used as a reflecting member, which is provided between the projection lens and the projection original image and reflects only light emitted from the projection original image and does not participate in color combination. The projection display device according to claim 5.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3314859A JPH05150361A (en) | 1991-11-28 | 1991-11-28 | Projection type display device |
| US08/327,803 US5537168A (en) | 1991-04-26 | 1994-10-24 | Projection optical apparatus comprising automatic adjustment unit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3314859A JPH05150361A (en) | 1991-11-28 | 1991-11-28 | Projection type display device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05150361A true JPH05150361A (en) | 1993-06-18 |
Family
ID=18058481
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3314859A Pending JPH05150361A (en) | 1991-04-26 | 1991-11-28 | Projection type display device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05150361A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007282110A (en) * | 2006-04-11 | 2007-10-25 | Nippon Telegr & Teleph Corp <Ntt> | Video input/output device |
| JP2011154159A (en) * | 2010-01-27 | 2011-08-11 | Canon Inc | Image projection apparatus |
| CN114460796A (en) * | 2021-12-16 | 2022-05-10 | 江西晶浩光学有限公司 | Light engine, display device, head-mounted equipment and packaging method of light engine |
-
1991
- 1991-11-28 JP JP3314859A patent/JPH05150361A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007282110A (en) * | 2006-04-11 | 2007-10-25 | Nippon Telegr & Teleph Corp <Ntt> | Video input/output device |
| JP2011154159A (en) * | 2010-01-27 | 2011-08-11 | Canon Inc | Image projection apparatus |
| CN114460796A (en) * | 2021-12-16 | 2022-05-10 | 江西晶浩光学有限公司 | Light engine, display device, head-mounted equipment and packaging method of light engine |
| CN114460796B (en) * | 2021-12-16 | 2024-04-12 | 江西晶浩光学有限公司 | Light engine, display device, head-mounted equipment and packaging method of light engine |
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