JP4333239B2 - Projection display - Google Patents

Description

【００３８】
【表２】

【００３９】
青色映像光の混色による赤色映像光の色度変化は、図１２に示した標準色度図上における識別域から色度(Ｒｘ＝０．６４近傍での識別楕円)のｘ軸とｙ軸の比率は約３：１である。すなわち、混色によりＲｘの変化に対してＲｙの変化の感度が３倍高い。
【００４０】
一方、赤色映像光再生時には赤色光束と光束量の１〜５％が混入された青色光束が赤色映像信号(図示せず)に応じて赤色用液晶パネル２１２で光強度変調され、光強度変調された赤色映像光と青色映像光がスクリーン(図示せず)に投写される。表１及び表２に示したように、スクリーン(図示せず)上でこれら２色(赤色映像光と青色映像光)を混色させることで得られる赤色光束の色度は、ΔＲｘ＝０．０８に対してΔＲｙ＝０．０４で約２倍であるためにｙ値が下がった効果が大きく、良好な色度(深い赤色)が得られたように感じられる。赤色映像光としては、Ｒｘが０．６０以上となることが望ましいので、青色映像光の混合率は３％混色以下にする必要があり、望ましくは２％以下とすると良い。
【００４１】
この時、３色を混合して得られた白色光束においては、上述したように、赤色映像信号で変調された青色光束を赤色映像光に混色すると、ｙ値が下がった良好な色度(深い赤色)を得ることができる。よって、従来技術においては赤色光束として使用出来なかった黄色成分を利用しても、ｙ値が高いオレンジ色光となることはない。すなわち、本発明では黄色成分が使用できるので、色バランスの向上と高い光束量(高輝度)の両立が可能となる。
【００４２】
上記した本発明の照明光学系においては、下記表３に示すように明るさは従来比で５％向上した。
【００４３】
【表３】

【００４４】
以上述べた本実施の形態の白色光束を赤色、青色、緑色光束に分離する場合のトリミングの方法について要点を下記に纏める。
【００４５】
赤色映像光の色度はダイクロイックミラー２０６の分光透過率特性とトリミングフィルタ２０８ｒの分光透過率特性により決まる。ダイクロイックミラー２０６の赤色領域の光に対する透過率の半値波長は、５７５〜５８５ｎｍ程度で従来同等である。そして、トリミングフィルタ２０８ｒの分光透過率特性として赤色領域の光に対する透過率の半値波長は図９に示すように５８５〜５９５ｎｍ程度とし、オレンジ色に近い成分を積極的にとり込み光束量を増やす。
【００４６】
更に、ローテータ２１０ｂ１の作用が青色のみＳ偏光をＰ偏光に変換するので、ＰＢＳ２０７ｇｂはＳ偏光である緑色領域の光を反射する特性を有しており、緑色領域の光に対する透過率の半値波長を短波長側では５１０〜５２５ｎｍ程度として青緑色成分を押さえ、また長波長側では逆にトリミングフィルタ２０８ｇの分光透過率特性として緑色領域の光に対する透過率の半値波長を５６５〜５７５ｎｍ程度とすることで黄緑色成分を増やして光束量を調整する。この結果、緑色成分の色度のｘ値は増加するが、赤色と緑色の混合色である肌色画像を再生する場合に青緑色成分が減少し変わりに黄色成分が入ることで、より自然な肌色再生が可能となる。
【００４７】
最後に青色光束は、ローテータ２１０ｂ１とトリミングフィルタ２０８ｂの特性により分光される。この時、透過率の長波長側の半値波長を、５００〜５２０ｎｍとする。一方、短波長側はＵＶカットフィルタ２２０の透過率の半値波長を４３０±３ｎｍ程度とすることで従来以上の信頼性が確保できる。
【００４８】
以上述べた本発明においては、以下に述べる作用により白色再生時の色温度を高く保ったままで良好な色バランスと高い光束量(高輝度)が実現できる。
【００４９】
青色映像再生時には青色に対応した青色用液晶パネルに青色映像信号が加わる。この時青色光束としては、従来技術より長波長側の光まで取り込むことで光束量を確保することができる。一方、緑色映像再生時には緑色に対応した緑色用液晶パネルに緑色映像信号が加わる。この時、従来技術において使用していた青色に近い領域(短波長側)の光は使用せず代わりに黄色に近い領域(長波長側)の光を使用して光束量のバランスを調整する。また、赤色用映像表示素子に入射する光束は従来技術において使用していた赤色に近い領域(長波長側)の光束だけでなく黄色に近い領域(短波長側)の光束も使用して光束量を稼ぐ。
【００５０】
赤色映像用として赤色光束に黄色成分まで取り込むと従来技術のままでは色度のｙ値が高いオレンジ色になるが、本願発明では青色光束量の数パーセントを予め赤色の光路に導いており、映像は青色成分により色度のｙ値が下げられるので、良好な赤色光束を得ることができる。図１２は標準色度図上における識別域を示すもので、波長５９０ｎｍ以上の赤色光領域においては色度のｘ値成分の変化がｙ値成分の変化に比べて感度が低く、すなわち同じ色として識別できる領域がｘ軸に沿って歪んだ楕円形状となっている。このためｘ値の変化はｙ値の変化に比べて分かり難いので、前述した解決技術により赤色再生時には明るくかつ良好な色度(深い赤色)が得られたように感じられる。また、３色を混合して得られた白色光束では従来使用出来なかった黄色成分が使用できるので色バランスと高い光束量(高輝度)が両立できる。また、本実施の形態では、偏光変換素子でＳ偏光に統一したがＰ偏光に統一してもよい。この場合の構成は、ローテータ２１０ｂ１を緑色用ローテータに置き換えればよい。
【００５１】
図４は、本発明による第２の実施の形態を示す投写型表示装置である。第１の実施の形態と異なる点は、１個のダイクロイックミラーと２個のＰＢＳを用いた点である。第１の実施の形態と動作が異なる照明光学系における色分離合成部について述べる。
【００５２】
白色光源２０１から放射された白色光束は、偏光変換素子２２１によって偏光状態をＳ偏光に統一され、ダイクロイックミラー２０６にて赤色光束を透過し、緑色光束と青色光束は反射される。
【００５３】
赤色光束は、１／２波長板２１２でＰ偏光に変換され、ＰＢＳ２０７ｗを透過し、トリミングフィルタ２０８ｒを経て、赤色用液晶パネル２０９ｒ上に照射される。入力映像信号に基づいて赤色光束は、赤色用液晶パネル２０９ｒでＰ偏光をＳ偏光に変換することによって赤色有効光にされ、ＰＢＳ２０７ｗを反射し、投写レンズ２１１に到達する。また変換されない赤色不要光は、Ｐ偏光のまま赤色用液晶パネル２０９ｒを反射するので、ＰＢＳ２０７ｗで透過する。
【００５４】
次にＳ偏光である緑色光束は、反射ミラー２２２で反射し、ＰＢＳ２０７ｇｂで反射し、トリミングフィルタ２０８ｇを経て、緑色用液晶パネル２０９ｇに照射される。そして、このトリミングフィルタ２０８ｇの分光透過率特性により分光される。この時、透過率の長波長側の半値波長は５６０±３ｎｍ程度である。入力映像信号に基づいて緑色光束は、緑色用液晶パネル２０９ｇでＳ偏光をＰ偏光に変換することによって緑色有効光にされ、ＰＢＳ２０７ｇｂを透過し、ＰＢＳ２０７ｗを透過し、投写レンズ２１１に到達する。一方、変換されない緑色不要光は、Ｓ偏光のまま反射するので、ＰＢＳ２０７ｇｂで反射する。
【００５５】
最後に、Ｓ偏光である青色光束は、反射ミラー２２２で反射し、ローテータ２１０ｂ１でＳ偏光がＰ偏光に変換され、ＰＢＳ２０７ｇｂを透過し、トリミングフィルタ２０８ｂを経て青色用液晶パネル２０９ｂに照射される。入力映像信号に基づいて青色光束は、青色用液晶パネル２０９ｂでＰ偏光がＳ偏光に変換することによって青色有効光にされ、ＰＢＳ２０７ｇｂで反射し、２つ目のローテータ２１０ｂ２でＳ偏光をＰ偏光に変換し、ＰＢＳ２０７ｗを透過し、投写レンズ２１１に到達する。一方、青色不要光は、Ｐ偏光のまま反射するので、ＰＢＳ２０７ｇｂを透過する。
【００５６】
以上が照明光学系における色分離合成部の説明である。前述した技術手段により赤色、緑色、青色に分離された各色の光束はそれぞれに対応する液晶パネル２０９ｒ、２０９ｇ、２０９ｂに入射し、映像信号の振幅に合わせて出射する光束量を変調し、最終的に、ＰＢＳ２０７ｗにより合成し、投写レンズ２１１でスクリーン上に拡大投影する。ここで、先程と同様に、ダイクロイックミラー２０６には、緑色光束と青色光束も幾分赤色光束側に透過させて赤色光束に混入させる分光透過率特性を持たせており、トリミングフィルタ２０８ｒには黄色の輝線をカットする特性を持たせている。このように構成することによって、先程と同様な効果が得られる。また、本実施の形態では、偏光変換素子でＳ偏光に統一したがＰ偏光に統一してもよい。この場合の構成は、ローテータ２１０ｂ１を緑色用ローテータに置き換え、１／２波長板２１２を取り除けばよい。
【００５７】
本実施の形態では、白色光源からの白色光束を、赤色光束と緑色光束と青色光束の３色光束に色分離する際、赤色光束と緑色・青色光束に分離する場合について、赤色光束に青色光束を混入させる本発明を述べた。しかし、本発明はこれに限定されるものではなく、例えば青色光束と赤色・緑色光束に分離し、さらに赤色光束と緑色光束に分離する場合にも適用可能である。この場合には、青色光束と赤色・緑色光束に分光させるダイクロイックミラーに赤色・緑色の光路側に青色光束量の１〜５％を導く分光透過率特性を持たせ、赤色光束と緑色光束に分光させるダイクロイックミラーに緑色光束と赤色・青色光束に分光させる分光透過率特性を持たせればよい。また、従来より使用されているダイクロイックミラーは、白色光束を赤色光束と緑色・青色光束とに完全には分離できる機能を有するものではない。よって、分離後の赤色光束にも若干の緑色・青色光束が含まれることになるため、従来より使用されているダイクロイックミラーと本実施の形態で説明した赤色用トリミングフィルタを用いる場合においても、本発明に適用できることは明らかである。
【００５８】
さらに、本実施の形態では、映像表示素子として反射型液晶パネルを用いたが、これに限定されるものではなく、光源からの光を映像信号に応じて光強度変調を行い画素毎の濃淡に変えた光学像を形成するものであればよく、例えば赤色、緑色、青色用の３板の微小反射鏡等を用いてもよいことはいうまでもない。なお、微小反射鏡を用いる場合には、偏光を利用しないので、映像表示素子の際に通常インテグレータ光学系と組合せて用いられる偏光変換素子は不要となる。
【００５９】
第３の実施の形態として、図１３に本発明の投写型表示装置を搭載した背面投写型表示装置を示す。図１３(ａ)は垂直方向断面図であり、図１３(ｂ)は正面図である。図１３において、投写型表示装置１１において得られる映像を投写用レンズ２１１により折り返しミラー１２を介してスクリーン１３上に拡大投写する構成となっている。１４は筐体、１５はバックカバーである。本実施の形態では、スクリーン１３の外形中心に対して投写レンズ２１１の光軸がほぼ一致する構成であり、画面周辺部でのフレネルレンズによる反射損失が四隅で均一となる。
【００６０】
【発明の効果】
本発明により高輝度表示を可能とする投写型表示装置を実現できる。
【図面の簡単な説明】
【図１】本発明による第１の実施の形態である赤色用液晶パネルに導く青色の光束量を規定するトリミングフィルタとダイクロイックミラーの分光透過率特性図。
【図２】従来の赤色用液晶パネルに導く青色の光束量を規定するトリミングフィルタとダイクロイックミラーの分光透過率特性図。
【図３】本発明による第１の実施の形態である投写型表示装置として１個のダイクロイックミラーと３個のＰＢＳを用いた場合の構成図。
【図４】本発明による第２の実施の形態である投写型表示装置として１個のダイクロイックミラーと２個のＰＢＳを用いた場合の構成図。
【図５】一般的な超高圧水銀ランプの分光エネルギー分布を示す特性図。
【図６】人間の目の比視感度特性を示す特性図。
【図７】色分離光学系の反射膜特性を示す特性図。
【図８】色分離光学系の反射膜特性を示す特性図。
【図９】色分離光学系の反射膜特性を示す特性図。
【図１０】ＣＩＥ１９６４色度図と黒体軌跡を示す特性図。
【図１１】黒体軌跡を示す特性図。
【図１２】標準色度図上における識別域を示す図。
【図１３】本発明による第２の実施の形態である背面投写型表示装置を示す図。
【符号の説明】
２０１…白色光源、２０２…第１のフライアイレンズ、２０３…第２のフライアイレンズ、２０４…合焦レンズ、２０５…フィールドレンズ、２０６…ダイクロイックミラー、２０７ｒ…赤色用ＰＢＳ、２０７ｇｂ…緑青色用ＰＢＳ、２０７ｗ…白色用ＰＢＳ、２０８ｒ…赤色用トリミングフィルタ、２０８ｇ…緑色用トリミングフィルタ、２０８ｂ…青色用トリミングフィルタ、２０９ｒ…赤色用液晶パネル、２０９ｇ…緑色用液晶パネル、２０９ｂ…青色用液晶パネル、２１０ｂ１、２１０ｂ２…青色用ローテータ、２１１…投写レンズ、２１２…１／２波長板、２２０…ＵＶカットフィルタ、２２１…偏光変換素子、２２２…折返しミラー、１１…投写型表示装置、１２…折返しミラー、１３…透過型スクリーン、１４…筺体、１５…バックカバー。[0001]
BACKGROUND OF THE INVENTION
In the present invention, a pixel having a means for modulating light intensity is divided into a matrix with a spectral optical system that splits light from a light source into light beams of each color of red, green, and blue. The present invention relates to a projection display device that is incident on a video display element arranged in a shape, and enlarges and projects light whose intensity is modulated in accordance with a video signal by the video display element.
[0002]
[Prior art]
As an example of a conventional projection display device such as a liquid crystal projector, there is a configuration in which a reflection type video display element is used as a video display element. For example, a light beam emitted from a white light source is separated into two light beams of an S-polarized component and a P-polarized component by a polarization beam separation element, and red (R) is provided in each optical path (color separation / combination system) of the separated light beam. A technology for improving the relative intensity of insufficient red (R) color light by providing redundant liquid crystal panels is disclosed (for example, see Patent Document 1). In addition, in order to solve problems such as a decrease in contrast, the polarization separation characteristics of the first polarization separation surface and the second polarization separation surface of the polarization beam splitter are determined by the role of each polarization separation surface and the required transmittance / There is disclosed a technique for making it differ according to the reflectance (for example, see Patent Document 2).
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 7-159751 (page 5, FIG. 2, FIG. 4)
[Patent Document 2]
Japanese Patent Laying-Open No. 2003-75778 (page 10, FIG. 1)
[0004]
[Problems to be solved by the invention]
The conventional projection display device has a problem in that both the brightness and the good color balance cannot be achieved because the amount of light (light quantity) of red and blue is insufficient with respect to the amount of light of green.
[0005]
Furthermore, when used as a home theater or television as a market that can be expected to expand significantly in the future, a color temperature of 6500 ° K to 9300 ° K or more is shown as the color temperature for white display on the black body locus shown in FIG. A set of color temperatures exceeding 15000 ° K is now available. For this reason, compatibility between brightness and color temperature has been a major issue in product development.
[0006]
The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a projection display device that achieves a good color balance and a high luminous flux (high luminance) while maintaining a high color temperature during white reproduction. And a rear projection display apparatus using the same.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a light source unit, an illumination optical unit that separates the light flux from the light source unit into red, green, and blue and irradiates the image display elements of the respective colors, and the illumination optical unit. An image display element that modulates the luminous flux into an optical image according to the amplitude of the video signal, a projection unit that projects the modulated luminous flux from the video display element on a screen, and displays red and blue when displaying in red Display control means for controlling the illumination optical unit so that blue display is simultaneously performed at a level of 1 / n (n is a natural number) of the display level, and the amount of light flux is increased while maintaining color balance To be configured.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0009]
FIG. 1 is a diagram showing a first embodiment according to the present invention. The spectral transmittance characteristics of a dichroic mirror that separates a red light beam (one color) and a green / blue light beam (two colors) and the red light path are arranged. The spectral transmittance characteristics of the trimming filter are shown. FIG. 3 shows an embodiment of a projection display device according to the present invention having the spectral transmittance characteristics of FIG.
[0010]
First, as an example of a projection display apparatus, FIG. 3 shows a case where a reflection type image display element is used as an image display element and a dichroic mirror and three polarization beam splitters (hereinafter referred to as PBS) are used. It explains using. In FIG. 3, the white light beam emitted from the white light source 201 is divided by the first fly-eye lens 202, and red by the second fly-eye lens 203, the focusing lens 204, and the field lens 205 disposed at the opposed positions. The enlarged liquid crystal panel 209r, the green liquid crystal panel 209g, and the blue liquid crystal panel 209b are enlarged and projected. For this reason, the energy distribution of the light flux incident on each liquid crystal panel is made uniform. The white light beam is separated into a red light beam and a green / blue light beam (cyan light beam) by a dichroic mirror 206 disposed in the optical path. The chromaticity of the red video light is determined by the spectral transmittance characteristic of the dichroic mirror 206 and the spectral transmittance characteristic of the trimming filter 208r. For home use, the wavelength (with which the transmittance of the dichroic mirror 206 with respect to light in the red region is 50% ( Hereinafter, the wavelength of 50% is referred to as a half-value wavelength) is set to about 580 nm. Further, as the spectral transmittance characteristic of the trimming filter provided in the lens 208r, the half-value wavelength of the transmittance for light in the red region is set to about 595 nm. In this case, the sharper the transmittance rise characteristic (transmittance change / wavelength), the less the color mixture, and the red purity improves.
[0011]
A specific basic action will be described with reference to FIGS. FIG. 2 is an explanatory diagram of the spectral transmittance characteristics of the dichroic mirror 206 and the trimming filter 208r in the red light path, and FIG. 5 is a characteristic diagram showing the spectral energy distribution of a general ultra-high pressure mercury lamp.
[0012]
The white light beam is separated into a red light beam and a green / blue light beam by the dichroic mirror 206 shown in FIG. By the way, as shown in FIG. 5, the spectral energy of the light beam emitted from the ultra-high pressure mercury lamp includes the blue light energy in the wavelength region from point a (435 nm) to point b (465 nm) and point c (535 nm). ) To d point (565 nm) and green light energy, and e light (600 nm) to f (630 nm) wavelength region. At this time, the red light energy is 1/3 or less of the blue light energy and the green light energy, and the relative light sensitivity characteristics shown in FIG. In particular, the energy of the luminous flux in the red wavelength band is small. In addition, there is a place where energy is large in the yellow wavelength region between green and red. Therefore, when color separation is performed only by the dichroic mirror 206, if the half-value wavelength of the dichroic mirror varies, the influence of the yellow bright line is great, and the chromaticity value changes greatly. Therefore, the yellow bright line is cut by the trimming filter 208r. Accordingly, since the blue light beam is cut in advance by the dichroic mirror 206 in front of the trimming filter 208r, the spectral transmittance characteristic of the trimming filter 208r arranged in the red optical path is usually the performance in the blue wavelength region. Is not required.
[0013]
The white light beam emitted from the white light source 201 is unified in the polarization state to S-polarized light by the polarization conversion element 221, the red light beam is transmitted by the dichroic mirror 206, and the green light beam and the blue light beam are reflected.
[0014]
First, the red light beam is reflected by the PBS 207r for red, passes through the trimming filter 208r, and is irradiated on the liquid crystal panel 209r for red. Based on the input video signal, the red luminous flux is converted into red effective light by converting S-polarized light into P-polarized light by the red liquid crystal panel 209r, passes through the PBS 207r, and converts the polarization state by 90 degrees. Is converted to S-polarized light, reflected by the PBS 207 w, and reaches the projection lens 211. Further, the unnecessary red light that is not converted is reflected by the PBS 207r for red because it is reflected by the red liquid crystal panel 209r with S-polarized light.
[0015]
The rotator 210b1 has a characteristic of converting the polarization state of the blue light beam from S-polarized light to P-polarized light, and the half-value wavelength at the boundary between the blue light beam to be converted and the green light beam that is not converted is about 505 ± 3 nm.
[0016]
Next, the green light beam that is S-polarized light is reflected by the PBS 207gb, and irradiated to the green liquid crystal panel 209g through the trimming filter 208g. In the spectral transmittance characteristic of the trimming filter 208g, the half-value wavelength of the transmittance for light in the green region is about 560 nm. Based on the input video signal, the green light beam is converted into green effective light by converting S-polarized light to P-polarized light by the green liquid crystal panel 209 g, passes through PBS 207 gb, passes through PBS 207 w, and reaches the projection lens 211. Further, the green unnecessary light that is not converted is reflected by the PBS 207gb because it reflects the green liquid crystal panel 209g with S-polarized light.
[0017]
Finally, since the blue light beam is converted from S-polarized light to P-polarized light by the rotator 210b1, it passes through the PBS 207gb, passes through the trimming filter 208b, and is applied to the blue liquid crystal panel 209b. Then, the light is split by the spectral transmittance characteristic of the trimming filter 208b. At this time, the half-value wavelength on the long wavelength side of the transmittance is about 485 ± 3 nm, and on the short wavelength side, the half-value wavelength of the transmittance of the UV cut filter 220 is about 428 ± 3 nm. Here, based on the input video signal, the blue light beam is converted into blue effective light by converting the P-polarized light into S-polarized light by the blue liquid crystal panel 209b, reflected by PBS 207gb, and S-polarized light by the second rotator 210b2. Since it is converted to P-polarized light, it passes through the PBS 207 w and reaches the projection lens 211. Moreover, since the blue unnecessary light which is not converted is reflected by P-polarized light, it passes through PBS 207gb.
[0018]
This is the description of the color separation / synthesis unit in the illumination optical system until the image display element is irradiated with the light beam from the white light source. The light beams of the respective colors separated into red, green, and blue by the above-described technical means are incident on the corresponding liquid crystal panels 209r, 209g, and 209b, respectively, and modulate the amount of light beam (light amount) emitted in accordance with the amplitude of the video signal. Finally, the image is synthesized by the PBS 207w and enlarged and projected on the screen by the projection lens 211.
[0019]
A feature of the present invention is that the dichroic mirror 206 has a characteristic that the green light beam and the blue light beam are somewhat transmitted to the red light beam side and mixed into the red light beam. The trimming filter 208r has the same spectral transmittance characteristic that allows the blue luminous flux to be transmitted without being cut, although the yellow bright line is cut as before.
[0020]
Due to the spectral transmittance characteristics described above, the white light beam from the white light source 1 is split into a red light beam and a green / blue light beam by the dichroic mirror 206. At this time, the green light beam and the blue light beam are also transmitted to the red light beam side somewhat. Mixed into the red light flux. Then, the red light beam mixed with the green light beam and the blue light beam is removed from the green light beam (including the yellow light beam) by the trimming filter 208r, and the red light beam mixed with the blue light beam is guided to the red liquid crystal panel 209r to obtain a red video signal. The red image light whose intensity is modulated by (not shown) and the mixed blue image light are projected on a screen (not shown).
[0021]
Accordingly, during red video light reproduction, the red chromaticity of the video on the screen can be made deep red by decreasing the y value in the chromaticity diagram of FIG. 10 (details will be described later). Accordingly, even if a yellow component that cannot be used as a red light beam in the prior art is used, an orange light beam having a high y value is not obtained, and the yellow component can be used. The amount of blue light flux mixed is about 1 to 5% of the blue light flux amount (details will be described later).
[0022]
The amount of blue light beam itself guided to the red liquid crystal panel 209r can be selected by a combination of the dichroic mirror 206 and the trimming filter 208r. For example, if the amount of the blue light beam before entering the dichroic mirror 206 is Φ, the blue light beam transmittance of the dichroic mirror 206 is T1, and the blue light beam transmittance of the trimming filter is T2, the red liquid crystal panel 209r is reached. The amount of blue light flux is Φ · T1 · T2. On the other hand, the amount of blue luminous flux reaching the original blue liquid crystal panel 209b is Φ · (1-T1). Therefore, the amount of the blue light beam guided to the red liquid crystal panel 209r is T1 · T2 / (1-T1) on the basis of the original light amount of the blue light beam. For example, when T1 = T2 = 9.5%, T1 · T2 / (1-T1) = 1% is obtained. However, the original luminous flux amount of the blue luminous flux is greatly reduced. On the other hand, if T1 = 1% and T2≈100%, the light flux amount of the blue light beam itself hardly decreases even if the light flux amount of the predetermined blue light beam is led to the red liquid crystal panel 209r. That is, the amount of the blue light beam guided to the red liquid crystal panel 209r is substantially determined by the transmittance of the blue light beam of the dichroic mirror 206, and the trimming filter 208r arranged in the red optical path allows the blue light beam to pass through almost 100%. This is important in order not to reduce the light amount itself of the original blue light beam. In addition to optical elements having a half-value wavelength, optical elements such as total reflection mirrors and polarizing plates are arranged. In actual color design, calculation is performed by multiplying the spectral transmittance characteristics of all these optical elements in order. I do.
[0023]
Here, the meaning of mixing the blue light beam with the red light beam will be described in detail. Conceptually, in the chromaticity diagram of FIG. 12, it can be analogized that the red chromaticity value is shifted to the blue side by mixing the red light beam with the blue light beam. Here, the description will be returned to the fundamental definition of X, Y, Z and chromaticity values (x, y) in chromaticity calculation. X, Y, and Z are the results of multiplying the spectral transmittance values of all optical elements from the white light source to the projection lens, etc. in each optical path, and the visibility values corresponding to X, Y, and Z. The combined amount. Further, the amount of luminous flux is Y, and the chromaticity values (x, y) are values normalized by Equation 1 and Equation 2.
[0024]
x = X / (X + Y + Z) (Equation 1)
y = Y / (X + Y + Z) (Expression 2)
Therefore, for the light flux amount Y and the chromaticity value (x, y) of each color, there are two variables, X and Z, in the above two equations, so X and Z can be obtained.
[0025]
Therefore, assume that the amount of light Y and the chromaticity (x, y) of white, red, green, and blue are as follows.
[0026]
Red Y = 217 x = 0.655, y = 0.345
Green Y = 635 x = 0.293, y = 0.694
Blue Y = 148 x = 0.140, y = 0.063
At this time, white Y = 1000, x = 0.259, y = 0.257, and further, X and Z of each color can be obtained from the above two equations.
[0027]
Red X = 412, Y = 217, Z = 0
Green X = 268, Y = 635, Z = 12
Blue X = 329, Y = 148, Z = 1873
Thus, blue has a large value of Z. Therefore, when the blue light beam is mixed with the red light beam, the denominator of the calculation formula of x and y becomes particularly large. On the other hand, since the increment of the molecule is relatively small, as a result, Δx <0 and Δy <0. In addition, in X and Y of blue, since X is larger, it seems that Δy <Δx <0, but Δx <Δy <0. The reason for this will be described next.
[0028]
A certain numerical value is represented by b / a, and values are respectively added to the denominator and the numerator to obtain (b + Δb) / (a + Δa). At this time, the condition for the value not to change before and after that is b / a = (b + Δb) / (a + Δa), which is obtained by modifying the equation to be Δb / Δa = b / a. That is, it can be seen that the condition for the value not to change before and after the addition depends on the size of the original number of molecules. Since x> y in red, this is the reason why Δx <Δy <0 in red after color mixing. The relationship between Δx and Δy in the identification area on the standard chromaticity diagram shown in FIG. 12 will be described later in Tables 1 and 2.
[0029]
Further, as a means for guiding a part of the amount of blue light flux to the red optical path, a method of further separating the blue wavelength region by a half-value wavelength with the dichroic mirror of FIG. If they are separated into wavelength ranges that are mixed in the red and red, the individual blue wavelength ranges become narrower. Since the influence of the variation in the half-value wavelength of the UV cut filter becomes large with respect to the narrow wavelength region, and the chromaticity value of white changes greatly, it is not preferable.
[0030]
As described above, the red light beam irradiated to the red liquid crystal panel 209r is mixed with the blue light beam, and when the red image light is reproduced, the red image light whose intensity is modulated by the red image signal (not shown) and the mixed blue image light are mixed. The features of the present invention projected onto a screen (not shown) have been outlined. Hereinafter, a first embodiment according to the present invention will be described in detail.
[0031]
In the image display device according to the present invention shown in FIG. 3, in order to realize the spectral transmittance characteristics shown in FIG. 1, the spectral transmittance characteristics and filter characteristics of the dichroic mirror 206, the trimming filters 208r, 208g, 208b, and the UV cut filter 220 are used. Is different from the conventional one.
[0032]
In FIG. 3, the white light beam emitted from the white light source 201 is separated into a red light beam and green / blue light beams by a dichroic mirror 206. In this embodiment, the half-value wavelength of the transmittance of the dichroic mirror 206 is 580 nm, which is the same as the conventional one, but the trimming filter 208r having the spectral transmittance characteristic shown by the solid line in FIG. 9 that determines the chromaticity of the red video light. The half-value wavelength of the transmittance was 587 nm. A yellow component that could not be used conventionally can be used by mixing a blue light beam with a red light beam, and a component close to orange can be actively taken in to increase the amount of light beam.
[0033]
Further, the light in the green region is separated by the first rotator 210b1 having the spectral transmittance characteristic shown by the solid line in FIG. 8 and the PBS 207gb. In the present embodiment, the blue-green component is suppressed by setting the half-value wavelength of the transmittance of the rotators 210b1 and 210b2 that determine the chromaticity of the green image light to 515 nm, and the half-value wavelength of the transmittance of the trimming filter 208g is 568 nm. Increased and adjusted the luminous flux. As a result, the x value of the chromaticity of the green component increases, but when reproducing a flesh-color image that is a mixed color of red and green, the blue-green component is decreased and the yellow component is entered instead. Playback is possible.
[0034]
Finally, the blue light beam is split by the trimming filter 208b having the spectral transmittance characteristic shown by the solid line in FIG. At this time, the half-value wavelength of the transmittance on the long wavelength side was set to 515 nm to increase the color balance and the amount of light flux, and on the short wavelength side, the half-value wavelength of the transmittance of the UV cut filter 220 was set to 431 nm to ensure higher reliability.
[0035]
Under the above conditions, in the illumination optical system described above, a 100 W input ultrahigh pressure mercury lamp (arc length: 1.0 mm) having the spectral energy distribution shown in FIG. Modeling how the chromaticity of the enlarged projected image on the screen changes due to the difference in characteristics between the dichroic mirror 206 and the trimming filter 208r constituting the color separation unit having transmittance characteristics was confirmed by simulation. The results are shown in Tables 1 and 2 below.
[0036]
In the simulation, based on the red, green, and blue light fluxes of the standard color design model, the specified amount of light flux of the color mixing source (red, green, and blue colors) is used as the color mixture destination (red, green , A calculation processing routine to be added to each color of blue). Therefore, in the calculation model, the luminance of the color mixing source and the color mixing destination and the chromaticity value of the color mixing destination change.
[0037]
[Table 1]

[0038]
[Table 2]

[0039]
The chromaticity change of the red image light due to the color mixture of the blue image light is the difference between the x axis and the y axis of the chromaticity (identification ellipse near Rx = 0.64) from the identification area on the standard chromaticity diagram shown in FIG. The ratio is about 3: 1. That is, the sensitivity of the change in Ry is three times higher than the change in Rx due to color mixing.
[0040]
On the other hand, at the time of red image light reproduction, a blue light beam mixed with a red light beam and 1 to 5% of the light amount is light intensity modulated by the red liquid crystal panel 212 in accordance with a red image signal (not shown) and light intensity modulated. The red image light and the blue image light are projected on a screen (not shown). As shown in Tables 1 and 2, the chromaticity of the red luminous flux obtained by mixing these two colors (red video light and blue video light) on a screen (not shown) is ΔRx = 0.08. On the other hand, since ΔRy = 0.04, which is approximately twice, the effect of lowering the y value is great, and it seems that good chromaticity (deep red) is obtained. As red image light, it is desirable that Rx is 0.60 or more. Therefore, the mixing ratio of blue image light needs to be 3% or less, preferably 2% or less.
[0041]
At this time, in the white light beam obtained by mixing the three colors, as described above, when the blue light beam modulated by the red video signal is mixed with the red video light, the chromaticity (deep deep) with a decreased y value is obtained. Red) can be obtained. Therefore, even if a yellow component that cannot be used as a red light beam in the prior art is used, orange light having a high y value is not obtained. That is, since the yellow component can be used in the present invention, it is possible to improve both color balance and high luminous flux (high luminance).
[0042]
In the above-described illumination optical system of the present invention, as shown in Table 3 below, the brightness is improved by 5% compared to the conventional art.
[0043]
[Table 3]

[0044]
The main points of the trimming method for separating the white light beam of the present embodiment described above into red, blue, and green light beams are summarized below.
[0045]
The chromaticity of the red video light is determined by the spectral transmittance characteristic of the dichroic mirror 206 and the spectral transmittance characteristic of the trimming filter 208r. The half-value wavelength of the transmittance of the dichroic mirror 206 with respect to the light in the red region is about 575 to 585 nm, which is equivalent to the conventional one. As the spectral transmittance characteristic of the trimming filter 208r, the half-value wavelength of the transmittance for light in the red region is set to about 585 to 595 nm as shown in FIG. 9, and a component close to orange is actively incorporated to increase the amount of light flux.
[0046]
Further, since the action of the rotator 210b1 converts only S-polarized light into P-polarized light, the PBS 207gb has a characteristic of reflecting light in the green region, which is S-polarized light, and has a half-value wavelength of transmittance for light in the green region. By suppressing the blue-green component as about 510 to 525 nm on the short wavelength side, and conversely on the long wavelength side, the half-value wavelength of the transmittance for green light is set to about 565 to 575 nm as the spectral transmittance characteristic of the trimming filter 208g. Adjust the amount of luminous flux by increasing the yellow-green component. As a result, the x value of the chromaticity of the green component increases, but when reproducing a flesh-color image that is a mixed color of red and green, the blue-green component is decreased and the yellow component is entered instead. Playback is possible.
[0047]
Finally, the blue light beam is split by the characteristics of the rotator 210b1 and the trimming filter 208b. At this time, the half-value wavelength on the long wavelength side of the transmittance is set to 500 to 520 nm. On the other hand, on the short wavelength side, by setting the half-value wavelength of the transmittance of the UV cut filter 220 to about 430 ± 3 nm, it is possible to ensure higher reliability than before.
[0048]
In the present invention described above, a good color balance and a high light flux (high luminance) can be realized while maintaining a high color temperature during white reproduction by the action described below.
[0049]
When reproducing a blue image, a blue image signal is added to the blue liquid crystal panel corresponding to the blue color. At this time, as the blue light beam, the amount of light beam can be ensured by taking even light having a longer wavelength than the prior art. On the other hand, a green video signal is added to the green liquid crystal panel corresponding to the green color when reproducing the green video. At this time, the light in the region close to blue (short wavelength side) used in the prior art is not used, but instead the light in the region close to yellow (long wavelength side) is used to adjust the light flux balance. In addition, the luminous flux incident on the red image display element uses not only the luminous flux close to red (long wavelength side) used in the prior art but also the luminous flux near yellow (short wavelength side). Earn.
[0050]
If the yellow component is incorporated into the red light flux for red images, the y value of the chromaticity will be orange with the conventional technology, but in the present invention, several percent of the blue light flux is led to the red light path in advance. Since the y value of chromaticity is lowered by the blue component, a good red luminous flux can be obtained. FIG. 12 shows an identification area on the standard chromaticity diagram. In the red light region having a wavelength of 590 nm or more, the change in the x-value component of chromaticity is lower than the change in the y-value component, that is, the same color. The region that can be identified has an elliptical shape distorted along the x-axis. For this reason, since the change in the x value is harder to understand than the change in the y value, it is felt that bright and good chromaticity (deep red) is obtained during the red reproduction by the above-described solution technique. In addition, since a yellow component that could not be used conventionally can be used in a white light beam obtained by mixing three colors, both color balance and a high light beam amount (high luminance) can be achieved. Further, in the present embodiment, the polarization conversion element is unified to S polarization, but may be unified to P polarization. In this case, the rotator 210b1 may be replaced with a green rotator.
[0051]
FIG. 4 shows a projection display apparatus according to the second embodiment of the present invention. The difference from the first embodiment is that one dichroic mirror and two PBSs are used. A color separation / synthesis unit in an illumination optical system that operates differently from the first embodiment will be described.
[0052]
The white light beam emitted from the white light source 201 is unified in the polarization state to S-polarized light by the polarization conversion element 221, the red light beam is transmitted by the dichroic mirror 206, and the green light beam and the blue light beam are reflected.
[0053]
The red light beam is converted to P-polarized light by the half-wave plate 212, passes through the PBS 207w, passes through the trimming filter 208r, and is irradiated onto the red liquid crystal panel 209r. Based on the input video signal, the red luminous flux is converted into red effective light by converting the P-polarized light into the S-polarized light by the red liquid crystal panel 209r, reflects the PBS 207w, and reaches the projection lens 211. Further, the unnecessary red light that is not converted is reflected by the red liquid crystal panel 209r while being P-polarized light, and is transmitted by the PBS 207w.
[0054]
Next, the S-polarized green light beam is reflected by the reflection mirror 222, reflected by the PBS 207gb, and irradiated to the green liquid crystal panel 209g through the trimming filter 208g. Then, the light is split by the spectral transmittance characteristic of the trimming filter 208g. At this time, the half-value wavelength of the transmittance on the long wavelength side is about 560 ± 3 nm. Based on the input video signal, the green light beam is converted into green effective light by converting S-polarized light to P-polarized light by the green liquid crystal panel 209 g, passes through PBS 207 gb, passes through PBS 207 w, and reaches the projection lens 211. On the other hand, the green unnecessary light that is not converted is reflected as S-polarized light, and is reflected by the PBS 207gb.
[0055]
Finally, the blue light beam that is S-polarized light is reflected by the reflection mirror 222, the S-polarized light is converted into P-polarized light by the rotator 210b1, passes through the PBS 207gb, and is irradiated to the blue liquid crystal panel 209b through the trimming filter 208b. Based on the input video signal, the blue light flux is converted into S effective light by converting the P polarized light into S polarized light by the blue liquid crystal panel 209b, reflected by PBS 207gb, and converted to S polarized light by the second rotator 210b2. The light is converted, passes through the PBS 207 w, and reaches the projection lens 211. On the other hand, since the blue unnecessary light is reflected with the P-polarized light, it passes through PBS 207gb.
[0056]
The above is the description of the color separation / synthesis unit in the illumination optical system. The light beams of the respective colors separated into red, green, and blue by the above-described technical means are incident on the corresponding liquid crystal panels 209r, 209g, and 209b, respectively, and the amount of the emitted light beam is modulated in accordance with the amplitude of the video signal. Then, the image is synthesized by the PBS 207 w and enlarged and projected on the screen by the projection lens 211. Here, similarly to the previous case, the dichroic mirror 206 has a spectral transmittance characteristic in which the green light beam and the blue light beam are somewhat transmitted to the red light beam side and mixed into the red light beam, and the trimming filter 208r has a yellow color. It has the characteristic of cutting the bright lines. By configuring in this way, the same effect as before can be obtained. Further, in the present embodiment, the polarization conversion element is unified to S polarization, but may be unified to P polarization. In this case, the rotator 210b1 may be replaced with a green rotator and the half-wave plate 212 may be removed.
[0057]
In this embodiment, when a white light beam from a white light source is separated into a three-color light beam of a red light beam, a green light beam, and a blue light beam, the red light beam is divided into a blue light beam and a green light beam. The invention has been described as incorporating. However, the present invention is not limited to this. For example, the present invention can be applied to a case where the light beam is separated into a blue light beam and a red / green light beam, and further separated into a red light beam and a green light beam. In this case, the dichroic mirror that splits the blue light flux and the red / green light flux has a spectral transmittance characteristic that guides 1 to 5% of the blue light flux on the red / green optical path side, and splits the red light flux and the green light flux. It is sufficient that the dichroic mirror to be provided has a spectral transmittance characteristic for separating the green light beam and the red / blue light beam. Further, the dichroic mirror conventionally used does not have a function capable of completely separating a white light beam into a red light beam and a green / blue light beam. Therefore, since the separated red light flux also includes some green and blue light fluxes, even when the conventionally used dichroic mirror and the red trimming filter described in this embodiment are used, this It is clear that it can be applied to the invention.
[0058]
Furthermore, in the present embodiment, a reflective liquid crystal panel is used as an image display element. However, the present invention is not limited to this. Light from a light source is modulated in accordance with a video signal to change the intensity of each pixel. Needless to say, any optical image can be used as long as it forms a changed optical image. For example, three-plate micro-reflecting mirrors for red, green, and blue may be used. In the case of using a micro-reflecting mirror, since polarized light is not used, a polarization conversion element that is usually used in combination with an integrator optical system in the case of an image display element becomes unnecessary.
[0059]
As a third embodiment, FIG. 13 shows a rear projection display device equipped with the projection display device of the present invention. FIG. 13A is a vertical sectional view, and FIG. 13B is a front view. In FIG. 13, an image obtained by the projection display device 11 is enlarged and projected onto the screen 13 via the folding mirror 12 by the projection lens 211. Reference numeral 14 denotes a housing, and 15 denotes a back cover. In the present embodiment, the optical axis of the projection lens 211 substantially coincides with the center of the outer shape of the screen 13, and the reflection loss due to the Fresnel lens at the periphery of the screen is uniform at the four corners.
[0060]
【The invention's effect】
According to the present invention, it is possible to realize a projection display device capable of high brightness display.
[Brief description of the drawings]
FIG. 1 is a spectral transmittance characteristic diagram of a trimming filter and a dichroic mirror that regulate the amount of a blue light beam guided to a red liquid crystal panel according to a first embodiment of the present invention;
FIG. 2 is a spectral transmittance characteristic diagram of a trimming filter and a dichroic mirror that define the amount of blue light flux guided to a conventional red liquid crystal panel.
FIG. 3 is a configuration diagram in the case where one dichroic mirror and three PBSs are used as the projection display apparatus according to the first embodiment of the present invention.
FIG. 4 is a configuration diagram when one dichroic mirror and two PBSs are used as a projection display apparatus according to a second embodiment of the present invention.
FIG. 5 is a characteristic diagram showing a spectral energy distribution of a general ultra-high pressure mercury lamp.
FIG. 6 is a characteristic diagram showing specific luminous sensitivity characteristics of human eyes.
FIG. 7 is a characteristic diagram showing a reflective film characteristic of a color separation optical system.
FIG. 8 is a characteristic diagram showing a reflective film characteristic of a color separation optical system.
FIG. 9 is a characteristic diagram showing a reflective film characteristic of a color separation optical system.
FIG. 10 is a characteristic diagram showing a CIE1964 chromaticity diagram and a black body locus.
FIG. 11 is a characteristic diagram showing a black body locus.
FIG. 12 is a diagram showing an identification area on a standard chromaticity diagram.
FIG. 13 is a diagram showing a rear projection display device according to a second embodiment of the present invention.
[Explanation of symbols]
201 ... white light source, 202 ... first fly eye lens, 203 ... second fly eye lens, 204 ... focus lens, 205 ... field lens, 206 ... dichroic mirror, 207r ... red PBS, 207gb ... green blue PBS, 207w ... PBS for white, 208r ... Trimming filter for red, 208g ... Trimming filter for green, 208b ... Trimming filter for blue, 209r ... Liquid crystal panel for red, 209g ... Liquid crystal panel for green, 209b ... Liquid crystal panel for blue, 210b1, 210b2 ... Blue rotator, 211 ... Projection lens, 212 ... Half wave plate, 220 ... UV cut filter, 221 ... Polarization conversion element, 222 ... Folding mirror, 11 ... Projection display device, 12 ... Folding mirror, 13 ... Transmission type screen, 14 ... Housing, 15 ... Kkukaba.

Claims (9)

The white light beam from the light source unit is separated into red, green and blue color light beams, irradiated to the video display elements of the respective colors to form an optical image by the amplitude of the video signal, and modulated from the video display elements of the respective colors A projection display device for projecting a light beam on a screen to display an image,
A polarization conversion element that aligns the white light flux in a predetermined polarization direction;
A first color separation unit that separates a white light beam aligned in a predetermined polarization direction by the polarization conversion element into a light beam of one color and two colors;
A second color separation unit for further separating light beams of two colors separated by the first color separation unit;
A trimming filter disposed on a red optical path color-separated by any one of the first color separation unit and the second color separation unit;
A reflective video display element for each color that modulates the red, green, and blue light beams separated by the first color separation unit and the second color separation unit into an optical image according to the amplitude of a video signal;
A color synthesizing unit for synthesizing the red, green, and blue light beams modulated into optical images in the reflective image display elements of the respective colors;
A projection unit for projecting the luminous flux synthesized by the color synthesis unit,
Of the light beams separated by the first color separation unit, green and blue are mixed in the light beam including red, and the trimming filter has a characteristic of transmitting the red region and the blue region and suppressing the green region. A projection display device characterized by that. A light source unit;
A polarization conversion element that aligns the white light flux from the light source unit in a predetermined polarization direction;
A dichroic mirror that separates a white light beam aligned in a predetermined polarization direction by the polarization conversion element into a red light beam, a green light beam, and a blue light beam;
A first polarizing beam splitter for separating and combining the green and blue light fluxes;
A trimming filter disposed on an optical path of a red light beam separated by the dichroic mirror;
A second polarizing beam splitter that acts as a polarizer or an analyzer for the red light beam separated by the dichroic mirror;
Green for red, green that modulates the green and blue light beams separated by the first polarizing beam splitter and the red light beam irradiated through the second polarizing beam splitter into an optical image by the amplitude of the video signal And blue reflective image display elements,
A third polarizing beam splitter for combining the light beams modulated into optical images in the reflective image display elements of the respective colors;
A projection lens that projects the light beam synthesized by the third polarization beam splitter,
A projection display apparatus , wherein green and blue are mixed in a red light beam separated by the dichroic mirror, and the trimming filter transmits a light beam in a half-value wavelength region of at least 525 nm and 585 nm. A light source unit;
A polarization conversion element that aligns the white light flux from the light source unit in a predetermined polarization direction;
A dichroic mirror for separating a white light beam aligned in a predetermined polarization direction by the polarization conversion element into a blue light beam, a red light beam, and a green light beam;
A first polarizing beam splitter that separates and combines the red and green luminous flux;
A trimming filter disposed on an optical path of a red light beam separated by the first polarizing beam splitter;
A second polarizing beam splitter that acts as a polarizer or an analyzer for the blue light beam separated by the dichroic mirror;
Red and green light that modulates the red light beam and green light beam separated by the first polarization beam splitter and the blue light beam irradiated through the second polarization beam splitter into an optical image by the amplitude of the video signal And blue reflective image display elements,
A third polarizing beam splitter for combining the light beams modulated into optical images in the reflective image display elements of the respective colors;
A projection lens that projects the light beam synthesized by the third polarization beam splitter,
A projection display apparatus , wherein red and green light beams separated by the dichroic mirror are mixed with blue, and the trimming filter transmits a light beam in a half-value wavelength region of at least 525 nm and 585 nm. A light source unit;
A polarization conversion element that aligns the white light flux from the light source unit in a predetermined polarization direction;
A dichroic mirror that separates a white light beam aligned in a predetermined polarization direction by the polarization conversion element into a red light beam, a green light beam, and a blue light beam;
A first polarizing beam splitter for separating and combining the green and blue light fluxes;
A trimming filter disposed on an optical path of a red light beam separated by the dichroic mirror;
A second polarizing beam splitter that functions as a polarizer or an analyzer for the red light beam separated by the dichroic mirror and has a function of combining red, green, and blue light beams;
The red, green, and blue light beams that modulate the green and blue light beams separated by the first polarization beam splitter and the red light beam that has passed through the second polarization beam splitter into an optical image according to the amplitude of the video signal. A reflective image display device for
A projection lens that projects a light beam obtained by combining the red, green, and blue light beams by the second polarizing beam splitter;
A projection display apparatus , wherein green and blue are mixed in a red light beam separated by the dichroic mirror, and the trimming filter transmits a light beam in a half-value wavelength region of at least 525 nm and 585 nm. A light source unit;
A polarization conversion element that aligns the white light flux from the light source unit in a predetermined polarization direction;
A dichroic mirror for separating a white light beam aligned in a predetermined polarization direction by the polarization conversion element into a blue light beam, a red light beam, and a green light beam;
A first polarizing beam splitter that separates and combines the red and green luminous flux;
A trimming filter disposed on an optical path of a red light beam separated by the first polarizing beam splitter;
A second polarization beam splitter that functions as a polarizer or an analyzer for the blue light beam separated by the dichroic mirror and has a function of combining red, green, and blue light beams;
Red, green, and blue light that modulates the red and green light beams separated by the first polarizing beam splitter and the blue light beam that has passed through the second polarizing beam splitter into an optical image according to the amplitude of the video signal. Reflection type image display element,
A projection lens that projects a light beam obtained by combining the red, green, and blue light beams by the second polarizing beam splitter;
A projection display apparatus , wherein red and green light beams separated by the dichroic mirror are mixed with blue, and the trimming filter transmits a light beam in a half-value wavelength region of at least 525 nm and 585 nm. The projection display device according to any one of claims 1 to 5,
6. The projection display device according to claim 1, wherein the light source unit has a light energy in a red light region less than a light energy in a green light region and a blue light region. The projection display device according to any one of claims 1 to 5,
The light source unit uses any one of an ultra-high pressure mercury lamp, a xenon lamp, and a metal haloid lamp. The projection display device according to any one of claims 1 to 5,
The projection display device, wherein the trimming filter transmits a light beam in a half-value wavelength region of 515 nm or less and 587 nm or more. The projection display device according to any one of claims 1 to 5,
The projection display device, wherein the polarization conversion element aligns the white light flux with S-polarized light.

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