M339005 八、新型說明： 【新型所屬之技術領域】 本創作是有關於一種投影裝置（projection apparatus)，且特 別是有關於一種投影裝置之光學引擎（optical engine)。 【先前技術】 請參照圖1，一種習知光學引擎100包括一超高壓汞燈（ultra high pressure mercury lamp, UHP mercury lamp) 110、一 光均勻 匕 模組（light uniforming module ) 120、一分合光系統（beam splitting and combining system) 130、三單晶石夕液晶面板（liquid crystal on silicon panel，LCOS panel) 140a、140b、140c 以及一投影鏡頭 (projection lens) 150。光均勻化模組120包括二透鏡陣列（lens array)122a、122b、一偏振轉換系統（polarization conversion system) 124以及一透鏡126。分合光系統130包括一分色單元（dichroic unit) 132、一分色鏡（dichroic mirror) 134、三偏振分光稜鏡 (polarizing beam splitting prism，PBS prism) 136a、136b、136c 以 及一 X稜鏡（Xcube) 138,其中分色單元132是由二互相交叉配 置之分色鏡132a與132b所構成。超高壓汞燈110適於發出一白 色光束束112。白色光束束112在穿過光均勻化模組120之偏振轉 換系統124後，會具有單一的偏振方向。 白色光束束112可視為由具有各種波長之部分光束所構成。 白色光束束112中之紅色部分光束112a會依序被分色鏡132a反 射、被偏振分光稜鏡136a反射、被單晶矽液晶面板H〇a反射、 穿透偏振分光稜鏡136a、被X棱鏡138反射以及傳遞至投影鏡頭 150。白色光束束112中之綠色部分光束U2b會依序被分色鏡132b 反射、被分色鏡134反射、被偏振分光稜鏡136b反射、被單晶矽 液晶面板140b反射、穿透偏振分光稜鏡136b、穿透X稜鏡138 6M339005 VIII. New Description: [New Technical Field] This creation relates to a projection apparatus, and in particular to an optical engine for a projection apparatus. [Prior Art] Referring to FIG. 1, a conventional optical engine 100 includes an ultra high pressure mercury lamp (UHP mercury lamp) 110, a light uniforming module 120, and a split. A beam splitting and combining system 130, a liquid crystal on silicon panel (LCOS panel) 140a, 140b, 140c and a projection lens 150. The light homogenization module 120 includes a lens array 122a, 122b, a polarization conversion system 124, and a lens 126. The split light system 130 includes a dichroic unit 132, a dichroic mirror 134, a polarizing beam splitting prism (PBS prism) 136a, 136b, 136c, and an X稜鏡(Xcube) 138, wherein the color separation unit 132 is composed of two dichroic mirrors 132a and 132b which are arranged to intersect each other. The ultrahigh pressure mercury lamp 110 is adapted to emit a white beam 112. The white beam 112 will have a single polarization direction after passing through the polarization conversion system 124 of the light homogenization module 120. The white beam 112 can be viewed as consisting of a portion of the beam having various wavelengths. The red partial beam 112a of the white beam 112 is sequentially reflected by the dichroic mirror 132a, reflected by the polarization beam splitter 136a, reflected by the single crystal germanium liquid crystal panel H〇a, penetrates the polarization beam splitter 136a, and is X prism. 138 is reflected and transmitted to the projection lens 150. The green partial beam U2b of the white beam 112 is sequentially reflected by the dichroic mirror 132b, reflected by the dichroic mirror 134, reflected by the polarization beam splitter 136b, reflected by the single crystal germanium liquid crystal panel 140b, and penetrates the polarization beam splitter. 136b, penetrating X稜鏡138 6
且能提高投影 M339005 以及傳遞至投雜頭150。自色縣束122 +之藍色部分光束n2c 會依序被分色鏡132b反射、穿透分色鏡134、被偏振分光棱鏡13& 反射、被單晶魏晶面板赚反射、穿透偏振分光棱鏡mc、被 X棱鏡138反射以及傳遞至投影鏡頭15〇。 /在習知光學引擎廳巾，由於白色光束束112在經過偏振轉 換糸統124後，光強度會降低了約15〜2〇%，導致光學引擎 所能提供的影像畫面的亮度變低。此外，由於超高壓汞燈ιι〇的 出光角度約為25°〜3G。，因此需採用較多的鏡片（如透鏡陣列 112a、112b、透鏡126及其他未緣示的透鏡）來使白色光束束ιΐ2 收斂，這會使得白色光束束112所行__較長，導致 擎100的體積增加。 【新型内容】 本創作提供一種光學引擎，其結構較為簡單 裝置所投影出的晝面之對比。 得到=:了其:目的和優點可以從本創作所揭露的技術特徵中 為達上述之一或部份或全部目的或是其他目的，本創作一實 施例提出—種光學弓丨擎，其包括—光源模組、-偏振分光單元 (polarizing beam splitting unit, PBS unit )、一分色單元、一第一 $邊（ight valve)、一第二光閥以及一第三光閥。光源模組適於 提供:藍色光束、-紅色光束與一綠色光束，其中藍色光束為一p 偏，光束，而紅色光束與綠色光束分別為-S偏振光束。偏振分 光单元疋配置於藍色光束、紅色光束與綠色光束的傳遞路徑上， 且，振t光單元適於反射S偏振絲，並使p偏振光束穿過。分 色單70疋配置於偏振分光單元之—侧，且位於被偏振分光單元反 射的紅色光束與綠色光束的傳遞路徑上。分色單元適於反射紅色 7 M339005 光束，並使綠色光束穿過。此外，第―光.配置於偏振分光單 元之另-側，且位於穿過偏振分光單元之藍色光束的傳遞路徑 上。第-光_於將藍色光束轉換成—藍色影像光束 beam)。第二細是配置於分色單元的_侧，絲於被分色單元 反射的紅色光束的㈣路徑上。第二光_於將紅色光束轉換成 -紅色影像光束。第三細是配置於分色單元的另—側，且位於 •穿過分色單元的綠色光束的傳遞路徑上。第三光_於將綠色光 束轉換成-綠色影像光束。另外，藍色影像光束自第—光閥離開 •後，，偏振分光單元反射。紅色影像光束自第二光_開後，被 分色單it反射並？過偏振分光單元。綠色影像光束自第三光闊離 開後，依序穿過分色單元及偏振分光單元，以與藍色影像光束及 紅色影像光束合併成一全彩影像光束（fullc〇1〇rimagebeam)。 “ 在本創作之一實施例中，上述之光源模組包括一第一同調光 .源（coherentlightso肌e)、一第二同調光源及一第三同調光源。 第一同調光源適於提供藍色光束，第二同調光源適於提供紅色光 束，而第三同調光源適於提供綠色光束。 在本創作之一實施例中，上述之光學引擎更包括一半波片 • (half_wavePlate)，配置於偏振分光單元與第一光閥之間。 在本創作之一實施例中，上述之偏振分光單元包括一偏振分 光稜鏡’而分色單元包括一分色棱鏡prism)，且偏振 • 分光單元鄰接分色單元。 在本創作之一實施例中，上述之光學引擎更包括一透光體， 位於偏振分光單元與第一光閥之間，且鄰接偏振分光單元。 在本創作之一實施例中，上述之光學引擎更包括一第一濾光 元件（trim filter),配置於透光體與第一光閥之間，以濾除藍色 光束之波長範圍以外的光。 M339005 在本創作之一實施例中，上述之第一濾光元件是位於透光體 之一表面上的一塗層（coatinglayer)。 一在本創作之一實施例中，上述之光學引擎更包括一第二濾光 ^件與一第三濾光元件。第二濾光元件是配置於分色單元與第二 ，閥之間，以濾除紅色光束之波長範圍以外的光。第三濾光元件 疋配置於分色單元與第三光閥之間，以濾除綠色光束之波長範圍 以外的光。It can also increase the projection M339005 and pass it to the dispensing head 150. The blue partial beam n2c of the self-color county beam 122+ is sequentially reflected by the dichroic mirror 132b, penetrates the dichroic mirror 134, is polarized by the dichroic prism 13&, is reflected by the single crystal Weijing panel, and penetrates the polarization beam splitting. The prism mc is reflected by the X prism 138 and transmitted to the projection lens 15A. / In the conventional optical engine hall towel, since the white beam 112 is subjected to the polarization conversion system 124, the light intensity is reduced by about 15 to 2%, resulting in a decrease in the brightness of the image displayed by the optical engine. In addition, since the exit angle of the ultrahigh pressure mercury lamp ιι is about 25° to 3G. Therefore, more lenses (such as lens arrays 112a, 112b, lens 126, and other lenses not shown) are used to converge the white beam ι ΐ 2, which causes the white beam 112 to travel longer, resulting in the engine 100. The volume increases. [New content] This creation provides an optical engine with a simple structure and contrast of the kneading surface projected by the device. Obtaining:: Purpose and Advantages From one or a part or all of the above or other objects in the technical features disclosed in the present invention, an embodiment of the present invention proposes an optical bow engine, which includes a light source module, a polarization concentrating unit (PBS unit), a color separation unit, a first ight valve, a second light valve, and a third light valve. The light source module is adapted to provide: a blue light beam, a red light beam and a green light beam, wherein the blue light beam is a p-biased light beam, and the red light beam and the green light beam are respectively -S polarized light beams. The polarization splitting unit 疋 is disposed on a transmission path of the blue beam, the red beam and the green beam, and the t-light unit is adapted to reflect the S-polarized wire and pass the p-polarized beam. The color separation sheet 70 is disposed on the side of the polarization beam splitting unit and is located on the transmission path of the red light beam and the green light beam reflected by the polarization beam splitting unit. The color separation unit is adapted to reflect the red 7 M339005 beam and pass the green beam. Further, the first light is disposed on the other side of the polarization splitting unit and is located on the transmission path of the blue light beam passing through the polarization splitting unit. The first light _ is converted into a blue light beam beam. The second thin is disposed on the _ side of the color separation unit, and the filament is on the (four) path of the red light beam reflected by the color separation unit. The second light _ converts the red light beam into a red image light beam. The third thinness is disposed on the other side of the color separation unit and is located on the transmission path of the green light beam passing through the color separation unit. The third light_ is used to convert the green light beam into a - green image light beam. In addition, after the blue image beam leaves the first light valve, the polarization beam splitting unit reflects. After the red light beam is turned from the second light, it is reflected by the color separation sheet it? Over-polarization beam splitting unit. After the green image beam leaves the third light, it passes through the color separation unit and the polarization beam splitting unit to form a full color image beam (fullc〇1〇rimagebeam) with the blue image beam and the red image beam. In one embodiment of the present invention, the light source module includes a first coherent light source (coherent lightso muscle e), a second coherent light source, and a third coherent light source. The first coherent light source is adapted to provide blue The color beam, the second coherent light source is adapted to provide a red light beam, and the third coherent light source is adapted to provide a green light beam. In one embodiment of the present invention, the optical engine described above further comprises a half wave plate (half_wavePlate), configured for polarization. In one embodiment of the present invention, the polarization splitting unit includes a polarization splitting unit and the color separation unit includes a dichroic prism (prism), and the polarization and spectroscopic unit is adjacent to the sub-lighting unit. In one embodiment of the present invention, the optical engine further includes a light transmissive body between the polarization beam splitting unit and the first light valve and adjacent to the polarization beam splitting unit. In an embodiment of the present invention, The optical engine further includes a first filter disposed between the light transmitting body and the first light valve to filter out light outside the wavelength range of the blue light beam. In one embodiment of the present invention, the first filter element is a coating layer on a surface of the light transmissive body. In an embodiment of the present invention, the optical engine further includes a first a second filter element and a third filter element. The second filter element is disposed between the color separation unit and the second valve to filter out light outside the wavelength range of the red light beam. The third filter element 疋The light separation unit is disposed between the color separation unit and the third light valve to filter out light outside the wavelength range of the green light beam.
s在本創作之一實施例中，上述之第二濾光元件與第三濾光元 件疋分別位於分色單元之兩相異表面上的塗層。 “在本創作之一實施例中，上述之第一光閥、第二光閥與第三 光閥為早晶妙液晶面板。 —在本創作之一實施例中，上述之光學引擎更包括一投影鏡 頭’配置於全彩影像光束的傳遞路徑上。 ^為達上述之一或部份或全部目的或是其他目的，本創作一實 靶例提出一種光學引擎，其包括一第一分色單元、一第二分色單 几、一光源模組、一第一偏振分光單元、一第二偏振分光單元、 =一光閥、一第二光閥及一第三光閥。第一分色單元具有一第 :分色部，而第二分色單元具有一第二分色部，且第一分色部與 (substantially) ;提供一藍色光束、一紅色光束與一綠色光束至第一分色部，其 中藍色光束為-P偏振縣，而紅色光束與綠色光束分別為一 ^ 2光束。第—分色部與第二分色部適於反射紅色光束，並使綠 光束與藍色光束通過。第一偏振分光單元是位於被第—分 ^射的紅色光束之傳遞路徑上，且具有一第一偏振分光部二 單的綠色光束與藍色光束的; k上且具有一第一偏振刀先部。第一偏振分光部與第二偏 9 M339005 振分光部的延伸方向實質上相同，而第一偏振分光部、第二偏振 分光部、第一分色部與第二分色部是排列成一又狀。第一偏振分 光部與第二偏振分光部適於反射S偏振光束，並使P偏振光束穿 過。此外，第一光閥是配置於通過第二偏振分光部的藍色光束之 傳遞路徑上，且第一光閥適於將藍色光束轉換成一藍色影像光 束。第二光閥是配置於被第一偏振分光部反射的紅色光束之傳遞 •路徑上，且第二光閥適於將紅色光束轉換成一紅色影像光束。第 二光閥疋配置於被第二偏振分光部反射的綠色光束之傳遞路徑 癱上，且第三光閥適於將綠色光束轉換成一綠色影像光束。另外， 藍色影像光束自第一光閥離開後，被第二偏振分光部反射而穿過 第二分色部。紅色影像光束自第二光閥離開後，穿過第一偏振分 光部，並被第二分色部反射。綠色影像光束自第三光閥離開後， _依序穿過第二偏振分光部及第二分色部，以與藍色影像光束及綠 色影像光束合併成一全彩影像光束。 在本創作之一實施例中，上述之光學引擎更包括一半波片， 配置於第一偏振分光單元與第二分色單元之間。 本創作之光學引擎中，由於使用的光學元件較少，所以具有 •體積小且成本低的優點。此外，由於偏振分光單元對s偏振光束 的反射率較對p偏振光束的穿透率高，且人眼對綠光較為敏感， •所以本創作藉由偏振分光單元將綠色暗場光束（s偏振光束）反 •射。如此，可大幅降低綠色暗場光束進入投影鏡頭中，進而提升 提高使用此光學引擎之投影裝置所投影出的畫面之對比。 為讓本創作之上述和其他目的、特徵和優點能更明顯易懂， 下文特舉較佳實施例，並配合所附圖式，作詳細說明如下。 【實施方式】 有關本創作之前述及其他技術内容、特點與功效，在以下配合參 M339005 考圖式之一較佳實施例的詳細說明中，將可清楚的呈現。以下實施例 中所提到的方向用語，例如：上、下、左、右、前或後等，僅是參考 附加圖式的方向。因此，使用的方向用語是用來說明並非用來限制本 創作。 [第一實施例] 圖2是本創作第一實施例之一種光學引擎的示意圖。請參照 圖2，本實施例之光學引擎20〇包括一光源模組21〇、一偏振分光 單元220、一分色單元230、一第一光閥240b、一第二光閥240r 以及一第三光閥240g。光源模組210適於提供一藍色光束212b、 一紅色光束212r與一綠色光束2l2g，其中藍色光束212b為一 p 偏振光束，而紅色光束212r與綠色光束212g分別為一 S偏振光 束。在本實施例中，光源模組210例如是包括一第一同調光源 214b、一第二同調光源214r及一第三同調光源2i4g。第一同調光 源214b適於提供藍色光束212b，第二同調光源2l4r適於提供紅 色光束212r，而第三同調光源214g適於提供綠色光束2i2g。此外， 第一同調光源214b、第二同調光源214r及第三同調光源2l4g可 為雷射光源，但不以此為限。 偏振分光單元220是配置於藍色光束212b、紅色光束212r與 綠色光束212g的傳遞路徑上，且偏振分光單元22〇適於反射s偏 振光束，並使P偏振光束穿過。此外，分色單元23〇是配置於偏 振分光單元220之一側，且位於被偏振分光單元22〇反射的紅色 光束212r與綠色光束212g的傳遞路徑上。分色單元23〇適於反射 紅色光束212r，並使綠色光束212g穿過。另外，在圖2中，偏振 分光單元220例如是一偏振分光棱鏡，分色單元23〇例如是鄰^ 偏振分光單元220的一分色稜鏡，但不以此為限。 第一光閥240b是配置於偏振分光單元22〇之另一側，且位於 M339005 穿過偏振分光單元220之藍色光束212b的傳遞路徑上。第一光閥 240b適於將藍色光束212b轉換成一藍色影像光束212b，。第二光 閥240r是配置於分色單元230的一側，且位於被分色單元230反 射的紅色光束212r之傳遞路徑上。第二光閥24〇r適於將紅色光束 212r轉換成一紅色影像光束212r’。第三光閥240g是配置於分色 單元230的另一侧，且位於穿過分色單元23〇的綠色光束212g的 傳遞路徑上。第三光閥240g適於將綠色光束212g轉換成一綠色 影像光束212g’。另外，藍色影像光束212b，被第一光閥24〇b反射 回偏振分光單元220，並被偏振分光單元220反射。紅色影像光束 參212r’被第二光閥240r及分色單元230依序反射並穿過偏振分光單 元220。綠色影像光束212g’被第三光閥240g反射並穿過分色單元 230及偏振分光單元220，以與藍色影像光束212b，及紅色影像光 - 束212r’合併成一全彩影像光束212f。 上述之第一光閥240b、第二光閥240r以及第三光閥240g皆 為反射式光閥。舉例來說，第一光閥240b、第二光閥240r與第三 光閥240g例如是通常開（normally ON)的單晶石夕液晶面板。本實 施例所用的單晶矽液晶面板在將入射光束轉換成影像光束時，還 參會改變入射光束的偏振方向。更詳細地說，每一單晶石夕液晶面板 包括多個畫素（pixel)。每一晝素會呈現「亮狀態」或「暗狀態」， 其中呈現「亮狀態」的畫素會改變入射光束的偏振方向，而呈現 _ 「暗狀態」的晝素不會改變入射光束的偏振方向。上述之藍色影 像光束212b’、紅色影像光束212r’及綠色影像光束212g，是指被呈 現「亮狀態」之晝素反射的光束。 在本實施例中，呈現「亮狀態」的畫素例如會將S偏振光束 轉換成P偏振光束。因此，本實施例之光學引擎200可更包括一 半波片250，其配置於偏振分光單元220與第一光閥240b之間， 12 M339005 以將光源模組210所提供之藍色光束（P偏振光束）212b轉換成 藍色光束（S偏振光束）212b。接著，通過半波片250的藍色光束 (S偏振光束）212b會被第一光閥240b轉換成藍色影像光束（p 偏振光束）212b’。之後，藍色影像光束（p偏振光束）212b，會被 半波片250轉換成藍色影像光束（S偏振光束）212b，，之後藍色 影像光束（S偏振光束）212b’會被偏振分光單元220反射。 另一方面，入射第二光閥240r的紅色光束（s偏振光束）212r 會被第二光閥240r轉換成紅色影像光束（P偏振光束）212r，。之 癱後，紅色影像光束（P偏振光束）212r’會被分色單元230反射至 偏振分光單元220，並且通過偏振分光單元220。此外，入射第三 光閥240g的綠色光束（S偏振光束）212g會被第三光閥240g轉 換成綠色影像光束（P偏振光束）212g，。之後，綠色影像光束（P _偏振光束）212g’會依序通過分色單元230及偏振分光單元220， 以與藍色影像光束（S偏振光束）212b’及紅色影像光束212r，（P 偏振光束）合併成全彩影像光束2l2f。 在本創作之一實施例中，上述之光學引擎2〇〇可更包括一投 影鏡頭260。此投影鏡頭26〇是配置於全彩影像光束⑽的傳遞 ❿路徑上，以將全彩影像光束212f投影於一螢幕（圖未式）上，進 而在螢幕上形成一畫面。 在上文中，傳遞至偏振分光單元22〇賴色影像光束2i2b，、 紅色影像光束212r’及綠色影像光束mg，是指被呈現「亮狀離」 旦實際上(如圖3所示），被呈現「嶋」 之旦素反射的&色暗場光束213b、紅色暗場料2l3r及綠色暗場 光束213g也會傳遞至偏振分光單元22()，其中藍色暗場光束^ 偏振光束）213b會穿過偏振分光單元22()，而紅色暗場光束（s 偏振光束）撕及綠色暗場光束（8偏振光束）2ug會被偏振分 13 M339005 光單το 220反射，用以使大部分的暗場光束不會入射 260。 ^ 圖4是偏振分光單元對不同波長之p偏振光束的反射率之曲 線圖，而® 5是偏振分光單元對不同波長之s偏振光束的穿透率 之曲線圖。由圖4可看出’雖然大部分的p偏振光束會穿過 分光單元,，0，但仍有少部分（約28〜45%)的p偏振光束會被 偏振分光單元220反射。由圖5可看出，雖然大部分的8偏^光 束會被偏振分光單元220反射，但仍有少部分（約〇 〇8%〜〇 2% ▲的S偏振光束會穿透偏振分光單元220。因此，仍有少部分Q •暗場光束犯b、紅色暗場光束213r及綠色暗場光有束21;:: 投影鏡頭260中。 θ 然而，由於人眼對綠光較為敏感，所以本實施例之光學引 _ 200特別設計成此架構，以讓傳遞至偏振分光單元220的綠色暗場 光束213g為s偏振光束而非Ρ偏振光束，如此僅約0 08%〜〇.2 %的綠色暗場光束213g會穿透偏振分光單元22〇而傳遞至投影鏡 頭260。因此，可大幅降低暗場光束對晝面之對比的不良影響;/進 而提升晝面的對比。此外，相較於習知技術，本實施例之光學引 _擎200架構較為簡單，且使用的光學元件也較少，所以具有體 小及成本低的優點。 、 、 .π -值得一提的是，在以偏振分光棱鏡及分色稜鏡作為偏振分光 -單元220及分色單元23〇的實施例中，光學引擎200可更包括一 透光體270。此透光體270是配置於偏振分光單元22〇與第一光 240b之間，且鄰接偏振分光單a 22〇，以使傳遞至投影鏡頭施 的藍色影像光束212b，、綠色影像光束212g，及紅色影像光束21^， 的光程(optical path)相同。透光體27〇的材質可選用折射率與偏振 分光稜鏡及分色棱鏡之折射率相近的材f，如玻璃，但不以此為 M339005 限。 此外，為了進一步提高晝面的對比，光學引擎2〇〇可更包括 一第一濾光元件280b、一第二濾光元件280r與一第三濾光元件 280g。第一濾光元件280b是配置於透光體270與第一光閥240b 之間，以濾除藍色光束212b之波長範圍以外的光。第二濾光元件 280r是配置於分色單元230與第二光閥24〇Γ之間，以濾除紅色光 束212r之波長範圍以外的光。第三濾光元件28〇g是配置於分色單 元230與第三光閥240g之間，以濾除綠色光束212g之波長範圍 以外的光。此外，第一濾光元件280b可以是位於透光體270之一 表面上的一塗層。第二濾光元件280r與第三濾光元件28吆可以是 位於分色單元230之兩表面上的塗層。 [第二實施例] • 圖6是本創作第二實施例之一種光學引擎的示意圖。請參照 圖6，本實施例之光學引擎300包括一光源模組31〇、一第一偏振 分光單元320a、一第二偏振分光單元320b —第一分色單元330a、 一第二分色單元330b、一第一光閥340b、一第二光閥340r以及一 第三光閥340g。光源模組310適於提供一藍色光束312b、一紅色 •光束312r與一綠色光束312g，其中藍色光束312b為一 P偏振光 束，而紅色光束312r與綠色光束312g分別為一 S偏振光束。在 本實施例中，光源模組310例如是包括一第一同調光源314b、一 第二同調光源314r及一第三同調光源314g。第一同調光源314b 適於提供藍色光束312b，第二同調光源314r適於提供紅色光束 312r，而第三同調光源314g適於提供綠色光束312g。此外，第一 同調光源314b、第二同調光源314r及第三同調光源314g可為雷 射光源，但不以此為限。 第一分色單元330a具有一第一分色部332a，而第二分色單元 15 M339005 330b具有-第二分色部332b，且第一分色部μ%與第二分色部 332b的延伸方向實質上相同。第一分色部與第二分色部 適於反射紅色光束312r，並使綠色光束312g與藍色光束312b通 過。光源模組310是將藍色光束312b、紅色光束312r與綠色光束 312g提供至第一分色部332a。 承上述，第一偏振分光單元32〇a是位於被第一分色部332a 反射的紅色光束312r之傳遞路徑上，且具有一第一偏振分光部 322a。第二偏振分光單元32〇b是位於通過第一分色部332&的綠 ^光束312g與藍色光束312b的傳遞路徑上，且具有一第二偏振 为光部322b。第一偏振分光部322a與第二偏振分光部322b的延 伸方向實質上相同，且第一偏振分光部322a、第二偏振分光部 322b、第一分色部332a與第二分色部332b是排列成一 χ狀。第 y偏振分光部322a與第二偏振分光部322b適於反射S偏振光束， 並使P偏振光束穿過。此外，在圖6中，第一偏振分光單元32〇a 與第二偏振分光單元32〇b例如分別為一偏振分光棱鏡，而第一分 色單元330a與第二分色單元330b例如分別為一分色棱鏡，但不 以此為限。 第一光閥340b是配置於通過第二偏振分光部322b的藍色光 束312b之傳遞路徑上，且第一光閥34〇1)適於將藍色光束312b轉 換成一藍色影像光束312b，。第二光閥340r是配置於被第一偏振 分光部322a反射的紅色光束312r之傳遞路徑上，且第二光閥340r 適於將紅色光束312r轉換成一紅色影像光束312r，。第三光閥340g 是配置於被第二偏振分光部322b反射的綠色光束312g之傳遞路 徑上’且第三光閥340g適於將綠色光束312g轉換成一綠色影像 光束312g’。 承上述，藍色影像光束312b，被第一光閥340b及第二偏振分 M339005 光部322b依序反射而穿過第二分色部332b。紅色影像光束3Ur， 被第二光閥340r反射而穿過第一偏振分光部322a，並被第二分色 部332b反射。綠色影像光束312g’被第三光閥34〇g反射而依序穿 過第二偏振分光部322b及第二分色部332b，以與藍色影像光束 3121?’及綠色影像光束312§’合併成一全彩影像光束312£^。 上述之第一光閥340b、第二光閥340r以及第三光閥340g皆 為反射式光閥。舉例來說，第一光閥340b、第二光閥340r與第三 光閥340g例如是與第一實施例相同（即通常開的單晶矽液晶面 、板）。此外，與第一實施例所述相似，本實施例所述之藍色影像 鲁光束312b、紅色影像光束312r’及綠色影像光束312g’是指被呈現 「亮狀態」之畫素反射的光束。 與第一實施例所述相似，在本實施例中，呈現「亮狀態」的 • 畫素例如會將S偏振光束轉換成P偏振光束。因此，本實施例之 光學引擎300可更包括一半波片350,其配置於第二偏振分光單元 320b與第一光閥340b之間，以將光源模組310所提供之藍色光束 (P偏振光束）312b轉換成藍色光束（S偏振光束）312b。接著， 通過半波片350的藍色光束（S偏振光束）312b會被第一光閥340b φ 轉換成藍色影像光束（P偏振光束）312b’。之後，藍色影像光束 (P偏振光束）312b’會被半波片350轉換成藍色影像光束（S偏 振光束）312b’，之後藍色影像光束（S偏振光束）312b’會被第二 偏振分光部322b反射而通過第二分色單元332b。In one embodiment of the present invention, the second filter element and the third filter element 上述 are respectively disposed on the two different surfaces of the color separation unit. In an embodiment of the present invention, the first light valve, the second light valve, and the third light valve are early crystal clear liquid crystal panels. In an embodiment of the present invention, the optical engine further includes a The projection lens is disposed on the transmission path of the full-color image beam. ^ In order to achieve one or a part or all of the above purposes or other purposes, the present invention provides an optical engine including a first color separation unit. a second color separation unit, a light source module, a first polarization beam splitting unit, a second polarization beam splitting unit, a light valve, a second light valve and a third light valve. The first color separation unit Having a first: color separation portion, and the second color separation unit has a second color separation portion, and the first color separation portion is substantially; providing a blue light beam, a red light beam and a green light beam to the first minute The color portion, wherein the blue light beam is a -P polarization county, and the red light beam and the green light beam are respectively a ^2 light beam. The first color separation portion and the second color separation portion are adapted to reflect the red light beam and make the green light beam and the blue light beam The light beam passes through. The first polarization splitting unit is located at the first The red light beam has a green light beam and a blue light beam with a first polarization splitting portion; k has a first polarization knife front portion; the first polarization splitting portion and the second partial polarization 9 M339005 The extending direction of the light splitting portion is substantially the same, and the first polarization splitting portion, the second polarization splitting portion, the first color separation portion, and the second color separation portion are arranged in a shape. The first polarization splitting portion and the second polarization splitting portion Suitable for reflecting the S-polarized beam and passing the P-polarized beam. Further, the first light valve is disposed on a transmission path of the blue light beam passing through the second polarization beam splitting portion, and the first light valve is adapted to be a blue light beam Converted into a blue image beam, the second light valve is disposed on a transmission path of the red light beam reflected by the first polarization beam splitting portion, and the second light valve is adapted to convert the red light beam into a red image beam. The 疋 is disposed on the transmission path 瘫 of the green light beam reflected by the second polarization splitting portion, and the third light valve is adapted to convert the green light beam into a green image light beam. In addition, after the blue image light beam leaves the first light valve, The second polarization splitting portion is reflected by the second polarization splitting portion and passes through the second color separation portion. After the red image beam leaves the second light valve, it passes through the first polarization beam splitting portion and is reflected by the second color separation portion. After the light valve leaves, _ sequentially passes through the second polarization splitting portion and the second color separation portion to combine with the blue image beam and the green image beam to form a full-color image beam. In an embodiment of the present invention, the above The optical engine further includes a half-wave plate disposed between the first polarization splitting unit and the second color separation unit. The optical engine of the present invention has the advantages of small size and low cost due to the use of fewer optical components. In addition, since the polarization splitting unit has a higher reflectance to the s-polarized beam than the p-polarized beam, and the human eye is more sensitive to green light, the present invention uses the polarization beam splitting unit to illuminate the green dark field beam (s-polarized). The light beam is reversed. This can greatly reduce the green dark field beam entering the projection lens, thereby improving the contrast of the image projected by the projection device using the optical engine. The above and other objects, features and advantages of the present invention will become more apparent and understood. [Embodiment] The foregoing and other technical contents, features, and functions of the present invention will be clearly described in the following detailed description of a preferred embodiment of the reference drawing. The directional terms mentioned in the following embodiments, for example, up, down, left, right, front or back, etc., are only directions referring to the additional drawings. Therefore, the directional terminology used is used to illustrate that it is not intended to limit the creation. [First Embodiment] Fig. 2 is a schematic view showing an optical engine of a first embodiment of the present invention. Referring to FIG. 2 , the optical engine 20 本 of the embodiment includes a light source module 21 , a polarization splitting unit 220 , a color separation unit 230 , a first light valve 240 b , a second light valve 240 r , and a third Light valve 240g. The light source module 210 is adapted to provide a blue light beam 212b, a red light beam 212r and a green light beam 2112g, wherein the blue light beam 212b is a p-polarized light beam, and the red light beam 212r and the green light beam 212g are respectively an S-polarized light beam. In this embodiment, the light source module 210 includes, for example, a first coherent light source 214b, a second coherent light source 214r, and a third coherent light source 2i4g. The first coherent light source 214b is adapted to provide a blue light beam 212b, the second coherent light source 214r is adapted to provide a red light beam 212r, and the third coherent light source 214g is adapted to provide a green light beam 2i2g. In addition, the first coherent light source 214b, the second coherent light source 214r, and the third coherent light source 214g may be laser light sources, but not limited thereto. The polarization beam splitting unit 220 is disposed on a transmission path of the blue light beam 212b, the red light beam 212r, and the green light beam 212g, and the polarization beam splitting unit 22 is adapted to reflect the s-polarized light beam and pass the P-polarized light beam. Further, the color separation unit 23A is disposed on one side of the polarization beam splitting unit 220, and is located on the transmission path of the red light beam 212r and the green light beam 212g reflected by the polarization beam splitting unit 22A. The color separation unit 23 is adapted to reflect the red light beam 212r and pass the green light beam 212g. In addition, in FIG. 2, the polarization splitting unit 220 is, for example, a polarization beam splitting prism, and the color separation unit 23 is, for example, a color separation of the adjacent polarization beam splitting unit 220, but is not limited thereto. The first light valve 240b is disposed on the other side of the polarization beam splitting unit 22, and is located on the transmission path of the blue light beam 212b passing through the polarization beam splitting unit 220 at M339005. The first light valve 240b is adapted to convert the blue light beam 212b into a blue image light beam 212b. The second light valve 240r is disposed on one side of the color separation unit 230 and is located on the transmission path of the red light beam 212r reflected by the color separation unit 230. The second light valve 24〇r is adapted to convert the red light beam 212r into a red image light beam 212r'. The third light valve 240g is disposed on the other side of the color separation unit 230 and is located on the transmission path of the green light beam 212g passing through the color separation unit 23''. The third light valve 240g is adapted to convert the green light beam 212g into a green image light beam 212g'. Further, the blue image beam 212b is reflected back to the polarization beam splitting unit 220 by the first light valve 24〇b, and is reflected by the polarization beam splitting unit 220. The red image beam reference 212r' is sequentially reflected by the second light valve 240r and the color separation unit 230 and passes through the polarization beam splitting unit 220. The green image beam 212g' is reflected by the third light valve 240g and passes through the color separation unit 230 and the polarization beam splitting unit 220 to combine with the blue image beam 212b and the red image beam-beam 212r' to form a full-color image beam 212f. The first light valve 240b, the second light valve 240r, and the third light valve 240g are all reflective light valves. For example, the first light valve 240b, the second light valve 240r, and the third light valve 240g are, for example, normally-on single crystal silicon solar panels. The single crystal germanium liquid crystal panel used in this embodiment also changes the polarization direction of the incident beam when converting the incident beam into an image beam. In more detail, each single crystal solar panel includes a plurality of pixels. Each element will have a "bright state" or a "dark state", in which the pixel in the "bright state" will change the polarization direction of the incident beam, and the pixel in the _ "dark state" will not change the polarization of the incident beam. direction. The blue image beam 212b', the red image beam 212r', and the green image beam 212g are light beams that are reflected by the pixels in the "bright state". In the present embodiment, a pixel exhibiting a "bright state", for example, converts an S-polarized beam into a P-polarized beam. Therefore, the optical engine 200 of the present embodiment may further include a half wave plate 250 disposed between the polarization beam splitting unit 220 and the first light valve 240b, and 12 M339005 to provide the blue light beam (P polarization) provided by the light source module 210. The light beam) 212b is converted into a blue light beam (S-polarized light beam) 212b. Next, the blue light beam (S-polarized light beam) 212b passing through the half-wave plate 250 is converted into a blue image light beam (p-polarized light beam) 212b' by the first light valve 240b. Thereafter, the blue image beam (p-polarized beam) 212b is converted into a blue image beam (S-polarized beam) 212b by the half-wave plate 250, and then the blue image beam (S-polarized beam) 212b' is polarized by the beam splitting unit. 220 reflections. On the other hand, the red light beam (s-polarized light beam) 212r incident on the second light valve 240r is converted into a red image light beam (P-polarized light beam) 212r by the second light valve 240r. After that, the red image beam (P-polarized light beam) 212r' is reflected by the color separation unit 230 to the polarization beam splitting unit 220, and passes through the polarization beam splitting unit 220. Further, the green light beam (S-polarized light beam) 212g incident on the third light valve 240g is converted into a green image light beam (P-polarized light beam) 212g by the third light valve 240g. Thereafter, the green image beam (P_polarized beam) 212g' is sequentially passed through the color separation unit 230 and the polarization beam splitting unit 220 to be combined with the blue image beam (S-polarized beam) 212b' and the red image beam 212r (P-polarized beam) ) merged into a full-color image beam 2l2f. In one embodiment of the present invention, the optical engine 2 described above may further include a projection lens 260. The projection lens 26 is disposed on the transmission path of the full-color image beam (10) to project the full-color image beam 212f onto a screen (Fig.) to form a picture on the screen. In the above, the red light image beam 2i2b, the red image beam 212r', and the green image beam mg, which are transmitted to the polarization beam splitting unit 22, are said to be "brightly separated" (actually shown in FIG. 3). The & color dark field beam 213b, the red dark field material 231r, and the green dark field light beam 213g which exhibit a "嶋" reflection are also transmitted to the polarization beam splitting unit 22(), wherein the blue dark field beam ^ polarized beam) 213b Will pass through the polarization beam splitting unit 22(), and the red dark field beam (s polarized beam) and the green dark field beam (8 polarized beam) 2ug will be reflected by the polarization 13 M339005 light sheet το 220 to make most of the The dark field beam is not incident on 260. Figure 4 is a plot of the reflectivity of a polarizing beam splitting unit for p-polarized beams of different wavelengths, and ® 5 is a plot of the transmittance of a polarizing beam splitting unit for s-polarized beams of different wavelengths. As can be seen from Fig. 4, although most of the p-polarized light beams pass through the spectroscopic unit, 0, a small portion (about 28 to 45%) of the p-polarized light beam is reflected by the polarization splitting unit 220. As can be seen from FIG. 5, although most of the 8 partial beams are reflected by the polarization beam splitting unit 220, there are still a small portion (about 8% to 〇2% ▲ of the S-polarized light beam will penetrate the polarization beam splitting unit 220. Therefore, there are still a small number of Q • dark field beam b, red dark field beam 213r and green dark field light beam 21;:: projection lens 260. θ However, since the human eye is sensitive to green light, The optical guide 205 of the embodiment is specifically designed to be such that the green dark field beam 213g transmitted to the polarization beam splitting unit 220 is an s-polarized beam instead of a Ρpolarized beam, so that only about 0 08%~〇.2% of green The dark field beam 213g passes through the polarization beam splitting unit 22〇 and is transmitted to the projection lens 260. Therefore, the adverse effect of the dark field beam on the contrast of the face can be greatly reduced; and the contrast of the face is improved. Knowing the technology, the optical lead-engine 200 of the present embodiment is relatively simple in structure and uses fewer optical components, so it has the advantages of small size and low cost. , , .π - It is worth mentioning that the light is split by polarization. Prism and color separation 稜鏡 as polarization splitting-unit 220 In the embodiment of the color separation unit 23A, the optical engine 200 may further include a light transmissive body 270. The light transmissive body 270 is disposed between the polarization beam splitting unit 22A and the first light 240b, and adjacent to the polarization splitting sheet a22. 〇, so that the optical path of the blue image beam 212b, the green image beam 212g, and the red image beam 21^ transmitted to the projection lens is the same. The material of the transparent body 27〇 can be selected from a refractive index and The polarizing beam splitter and the dichroic prism have similar refractive indices f, such as glass, but are not limited to M339005. In addition, in order to further improve the contrast of the facet, the optical engine 2 may further include a first filter. The element 280b, a second filter element 280r and a third filter element 280g. The first filter element 280b is disposed between the light transmitting body 270 and the first light valve 240b to filter out the wavelength of the blue light beam 212b. Light outside the range. The second filter element 280r is disposed between the color separation unit 230 and the second light valve 24A to filter out light outside the wavelength range of the red light beam 212r. The third filter element 28〇g Is disposed between the color separation unit 230 and the third light valve 240g The light outside the wavelength range of the green light beam 212g is filtered out. Further, the first filter element 280b may be a coating layer on one surface of the light transmitting body 270. The second filter element 280r and the third filter element 28 The 吆 may be a coating on both surfaces of the color separation unit 230. [Second Embodiment] Fig. 6 is a schematic view of an optical engine according to a second embodiment of the present invention. Referring to Fig. 6, the optical engine of the present embodiment 300 includes a light source module 31〇, a first polarization splitting unit 320a, a second polarization splitting unit 320b—a first color separation unit 330a, a second color separation unit 330b, a first light valve 340b, and a second The light valve 340r and a third light valve 340g. The light source module 310 is adapted to provide a blue light beam 312b, a red light beam 312r and a green light beam 312g, wherein the blue light beam 312b is a P-polarized light beam, and the red light beam 312r and the green light beam 312g are respectively an S-polarized light beam. In this embodiment, the light source module 310 includes, for example, a first coherent light source 314b, a second coherent light source 314r, and a third coherent light source 314g. The first coherent light source 314b is adapted to provide a blue beam 312b, the second coherent source 314r is adapted to provide a red beam 312r, and the third coherent source 314g is adapted to provide a green beam 312g. In addition, the first coherent light source 314b, the second coherent light source 314r, and the third coherent light source 314g may be laser light sources, but not limited thereto. The first color separation unit 330a has a first color separation portion 332a, and the second color separation unit 15 M339005 330b has a second color separation portion 332b, and an extension of the first color separation portion μ% and the second color separation portion 332b The directions are essentially the same. The first color separation portion and the second color separation portion are adapted to reflect the red light beam 312r and pass the green light beam 312g and the blue light beam 312b. The light source module 310 supplies the blue light beam 312b, the red light beam 312r, and the green light beam 312g to the first color separation portion 332a. As described above, the first polarization splitting unit 32A is located on the transmission path of the red light beam 312r reflected by the first color separation portion 332a, and has a first polarization beam splitting portion 322a. The second polarization splitting unit 32'b is located on the transmission path of the green beam 312g and the blue beam 312b passing through the first color separation portion 332& and has a second polarization as the light portion 322b. The first polarization splitting portion 322a and the second polarization splitting portion 322b extend substantially in the same direction, and the first polarization splitting portion 322a, the second polarization splitting portion 322b, the first color separation portion 332a, and the second color separation portion 332b are arranged. Into a shape. The y-polarized beam splitting portion 322a and the second polarizing beam splitting portion 322b are adapted to reflect the S-polarized beam and pass the P-polarized beam. In addition, in FIG. 6, the first polarization splitting unit 32a and the second polarization splitting unit 32b are, for example, a polarization beam splitting prism, respectively, and the first color separation unit 330a and the second color separation unit 330b are, for example, one. Dichroic prism, but not limited to this. The first light valve 340b is disposed on a transmission path of the blue light beam 312b passing through the second polarization splitting portion 322b, and the first light valve 34〇1) is adapted to convert the blue light beam 312b into a blue image light beam 312b. The second light valve 340r is disposed on a transmission path of the red light beam 312r reflected by the first polarization splitting portion 322a, and the second light valve 340r is adapted to convert the red light beam 312r into a red image light beam 312r. The third light valve 340g is disposed on the transmission path of the green light beam 312g reflected by the second polarization splitting portion 322b, and the third light valve 340g is adapted to convert the green light beam 312g into a green image light beam 312g'. As a result, the blue image beam 312b is sequentially reflected by the first light valve 340b and the second polarization portion M339005 light portion 322b and passes through the second color separation portion 332b. The red image beam 3Ur is reflected by the second light valve 340r and passes through the first polarization splitting portion 322a, and is reflected by the second color separation portion 332b. The green image beam 312g' is reflected by the third light valve 34〇g and sequentially passes through the second polarization splitting portion 322b and the second color separation portion 332b to merge with the blue image beam 3121?' and the green image beam 312' Into a full color image beam 312 £ ^. The first light valve 340b, the second light valve 340r, and the third light valve 340g are all reflective light valves. For example, the first light valve 340b, the second light valve 340r, and the third light valve 340g are, for example, the same as the first embodiment (i.e., a normally open single crystal germanium liquid crystal surface, plate). Further, similarly to the first embodiment, the blue image light beam 312b, the red image light beam 312r', and the green image light beam 312g' described in the present embodiment refer to a light beam reflected by a pixel that exhibits a "bright state". Similar to the first embodiment, in the present embodiment, a pixel exhibiting a "bright state", for example, converts an S-polarized beam into a P-polarized beam. Therefore, the optical engine 300 of the present embodiment may further include a half wave plate 350 disposed between the second polarization splitting unit 320b and the first light valve 340b to provide a blue light beam (P polarization) provided by the light source module 310. The light beam 312b is converted into a blue light beam (S-polarized light beam) 312b. Next, the blue light beam (S-polarized light beam) 312b passing through the half-wave plate 350 is converted into a blue image light beam (P-polarized light beam) 312b' by the first light valve 340b φ. Thereafter, the blue image beam (P-polarized beam) 312b' is converted into a blue image beam (S-polarized beam) 312b' by the half-wave plate 350, after which the blue image beam (S-polarized beam) 312b' is subjected to the second polarization. The light splitting portion 322b reflects and passes through the second color separation unit 332b.
另一方面，入射第二光閥340r的紅色光束（S偏振光束）312r 會被第二光閥340r轉換成紅色影像光束（P偏振光束）312r，。之 後，紅色影像光束（P偏振光束）312r，會通過第一偏振分光部322a 並被第二分色部332b反射。此外，入射第三光閥340g的綠色光 束（S偏振光束）312g會被第三光閥340g轉換成綠色影像光束（P 17 M339005 偏振光束）312g’。之後’綠色影像光束（p偏振光束）叫，會依 序通過第二偏振分光部322b與第二分色部33处，以與藍色影像光 束312b，及紅色影像光束312r，合併成全彩影像光束3以。 在本創作之一實施例中，上述之光學引擎3〇〇可更包括一投 衫鏡頭360。此投影鏡頭360是配置於全彩影像光束312f的傳遞 路徑上，以將全彩影像光束312f投影於一螢幕（圖未式）上，進 而在螢幕上形成一畫面。 與第一實施例所述相似，藍色影像光束3121)，、紅色影像光束 312r’及綠色影像光束312g，是指被呈現「亮狀態」之畫素反射的光 束。但實際上（如圖7所示），被呈現「暗狀態」之畫素反射的 藍色暗場光束313b及綠色暗場光束313g也會傳遞至第二偏振分 光部322b，而被呈現「暗狀態」之晝素反射的紅色暗場光束313r 也會傳遞至第一偏振分光部322a。藍色暗場光束（p偏振光束） 313b會穿過第二偏振分光部322b，綠色暗場光束（8偏振光束） 313g會被第二偏振分光部322b反射，而紅色暗場光束（s偏振光 束）313r會被第一偏振分光部322a反射，用以使大部分的暗場光 束不會入射投影鏡頭360。 然而，由於第一偏振分光部322a與第二偏振分光部322b無 法完全將S偏振光束反射，並使p偏振光束完全通過，所以仍有 少部分的藍色暗％光束313b、紅色暗場光束313r及綠色暗場光束 313g會進入投影鏡頭360中。此外，由於人眼對綠光較為敏感， 所以本實施例之光學引擎300特別設計成此架構，以讓傳遞至第 —偏振分光部322b的綠色暗場光束313g為S偏振光束而非p偏 振光束，如此僅約0.08%〜0.2%的綠色暗場光束313g會穿透第二 偏振分光部322b而傳遞至投影鏡頭360。因此，可大幅降低暗場 光束對畫面之對比的不良影響，進而提升晝面的對比。此外，相 M339005 知技術，本實施例之光學引擎架構較為簡單，且使用 的先子1也較少，所以具有體積小及成本低的優點。 ㈣色單元對不同波長之P偏振光束及s偏振光束的反 rtTt 6^® 8^® 8 ^ 犯圍内’ 色單元320a與第二分色單元3勘對8偏振 的反射率高於對p偏振光束的反射率。因此，本實補之光學引 擎!，可!1包括—半波片37°，配置於第一偏振分光單元320a與 第^刀色單TO 330b之間。此半波片37〇可將紅色影像光束（p偏 振光束）312r’轉換成紅色影像光束（s偏振光束）仙，，以使傳 遞至分色單元32Gb的紅色影像光束3121·，為S偏振光束，如 此可提尚紅色影像光束312r，被第二分色單元32〇b反射至投影鏡 頭360的比率，進而提升畫面的亮度。 - 請參照圖6，為了進一步提高晝面的對比，光學引擎300可更 包括一第一濾光元件380b、一第二濾、光元件380r與一第三滤光元 件380g。第一濾光元件380b是配置於第二偏振分光單元32〇b與 第一光閥340b之間，以濾除藍色光束312b之波長範圍以外的光。 第二濾光元件380r是配置於第一偏振分光單元320a與第二光閥 籲340r之間，以濾除紅色光束312r之波長範圍以外的光。第三濾光 元件380g是配置於第二偏振分光單元32〇b與第三光閥340g之 •間，以濾除綠色光束312g之波長範圍以外的光。此外，第二濾光 元件380r可以是位於第一偏振分光單元320a之一表面上的一塗 層。第一濾光元件380b與第三濾光元件380g可以是位於第二偏 振分光單元320b之兩表面上的塗層。 綜上所述，本創作之光學引擎至少具有下列優點： 1·本創作之光學引擎所使用的光學元件較少，所以具有體積 小且成本低的優點。 M339005 2.由於偏振》光單元對s偏振光束的反射率較對p偏振光束 的穿透率高’且人眼對綠光較為敏感，所以本創作的架構是設計 成偏振分光單元將綠色暗場光束（s偏振光束）反射。如此，可大 =低綠色暗場光束進人投職射，_提升提高使用此光學 引擎之投影裝置所投影出的晝面之對比。 贫可，第—光閥、第二細及第三光閥之前分別設置 元件帛一滤光元件及第三濾光元件以一 面的對比。^ 4.本創作第二實施例中’在第—偏振分光單元與第二分色單On the other hand, the red light beam (S-polarized light beam) 312r incident on the second light valve 340r is converted into a red image light beam (P-polarized light beam) 312r by the second light valve 340r. Thereafter, the red image beam (P-polarized beam) 312r passes through the first polarization splitting portion 322a and is reflected by the second color separation portion 332b. Further, the green beam (S-polarized beam) 312g incident on the third light valve 340g is converted into a green image beam (P 17 M339005 polarized beam) 312g' by the third light valve 340g. Then, the 'green image beam (p-polarized beam) is sequentially passed through the second polarization beam splitting portion 322b and the second color separation portion 33 to combine with the blue image beam 312b and the red image beam 312r to form a full-color image beam. 3 to. In one embodiment of the present invention, the optical engine 3 described above may further include a shirting lens 360. The projection lens 360 is disposed on the transmission path of the full-color image beam 312f to project the full-color image beam 312f onto a screen (Fig.) to form a picture on the screen. Similar to the first embodiment, the blue image beam 3121), the red image beam 312r', and the green image beam 312g refer to the beam reflected by the pixel in the "bright state". However, in reality (as shown in FIG. 7), the blue dark field beam 313b and the green dark field beam 313g which are reflected by the pixel in the "dark state" are also transmitted to the second polarization splitting portion 322b, and are presented as "dark". The red dark field beam 313r reflected by the elemental state is also transmitted to the first polarization splitting portion 322a. The blue dark field beam (p-polarized beam) 313b passes through the second polarization beam splitting portion 322b, the green dark field beam (8-polarized beam) 313g is reflected by the second polarizing beam splitting portion 322b, and the red dark field beam (s polarized beam) The 313r is reflected by the first polarization splitting portion 322a so that most of the dark field beam does not enter the projection lens 360. However, since the first polarization splitting portion 322a and the second polarization splitting portion 322b cannot completely reflect the S-polarized beam and pass the p-polarized beam completely, there are still a small portion of the blue dark % light beam 313b and the red dark field light beam 313r. And the green dark field beam 313g will enter the projection lens 360. In addition, since the human eye is sensitive to green light, the optical engine 300 of the present embodiment is specifically designed such that the green dark field beam 313g transmitted to the first polarization splitting portion 322b is an S-polarized beam instead of a p-polarized beam. Thus, only about 0.08% to 0.2% of the green dark field beam 313g will pass through the second polarization beam splitting portion 322b and be transmitted to the projection lens 360. Therefore, the adverse effects of the dark field beam on the contrast of the picture can be greatly reduced, thereby improving the contrast of the face. In addition, according to the technology of the phase M339005, the optical engine architecture of the embodiment is relatively simple, and the use of the first child 1 is also small, so that it has the advantages of small size and low cost. (4) The color unit is opposite to rpTt 6^® 8^® 8 ^ of the P-polarized beam and the s-polarized beam of different wavelengths. The reflectance of the 8-color polarization is higher than that of the second color separation unit 3a and the second color separation unit 3 The reflectivity of the polarized beam. Therefore, the optical engine of the present invention can be arranged to be disposed between the first polarization splitting unit 320a and the second color shifting unit TO 330b. The half-wave plate 37A converts the red image beam (p-polarized beam) 312r' into a red image beam (s-polarized beam), so that the red image beam 3121· transmitted to the color separation unit 32Gb is an S-polarized beam. Thus, the ratio of the red image beam 312r reflected by the second color separation unit 32〇b to the projection lens 360 can be raised, thereby increasing the brightness of the image. - In order to further improve the contrast of the facet, the optical engine 300 may further include a first filter element 380b, a second filter, a light element 380r and a third filter element 380g. The first filter element 380b is disposed between the second polarization splitting unit 32〇b and the first light valve 340b to filter out light outside the wavelength range of the blue light beam 312b. The second filter element 380r is disposed between the first polarization splitting unit 320a and the second light valve 340r to filter out light outside the wavelength range of the red light beam 312r. The third filter element 380g is disposed between the second polarization splitting unit 32bb and the third light valve 340g to filter out light outside the wavelength range of the green light beam 312g. Further, the second filter element 380r may be a coating layer on one surface of the first polarization splitting unit 320a. The first filter element 380b and the third filter element 380g may be coating layers on both surfaces of the second polarization splitting unit 320b. In summary, the optical engine of the present invention has at least the following advantages: 1. The optical engine of the present invention uses fewer optical components, so it has the advantages of small size and low cost. M339005 2. Since the polarization unit has a higher reflectivity to the s-polarized beam than the p-polarized beam, and the human eye is more sensitive to green light, the architecture of the present design is designed to be a polarizing beam splitting unit. The beam (s-polarized beam) is reflected. In this way, the large = low green dark field beam enters the shot, _ boosts the contrast of the face projected by the projection device using the optical engine. Lean, the first light valve, the second thin and the third light valve are respectively provided with a comparison of the element, the filter element and the third filter element. ^ 4. In the second embodiment of the present invention, the first polarization polarization splitting unit and the second color separation list
Hi置半波I可使傳遞至第二分色單元的紅色影像光束為S 爲振光束’所叫提高紅色影像光束被第二分色單元反射至投影 鏡頭的比率，進而提升晝面的亮度。 雖然，_已以_實施_露如±，然錢非用以限定本 ”!廟所屬Ϊ術領域中具有通常知識者，在*脫離本創作之精神 和ί 胃可作些許之更動與潤飾，因此本創作之賴範圍當 專利範圍所界定者為準。另外本創作的任一實施例 二。：外利：圍Γ須達成本創作所揭露之全部目的或優點或特 \ 要部分和標題僅是用來輔助專利文件搜尋之用，並Hi sets the half-wave I to make the red image beam transmitted to the second color separation unit the ratio of S to the vibration beam, which is used to increase the ratio of the red image beam reflected by the second color separation unit to the projection lens, thereby increasing the brightness of the pupil surface. Although, _ has been implemented _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Therefore, the scope of this creation is subject to the definition of patent scope. In addition, any example of this creation is two.: Foreign interest: the cofferdam must achieve all the purposes or advantages disclosed in this creation or the special part and title only Is used to assist in the search of patent documents, and
非用來限制本創作之權利範圍。 I 【圖式簡單說明】 圖1是習知一種光學引擎的示意圖。 圖2是本創作第一實施例之一種光學引擎的示意圖。 圖3 ^圖2之光學引擎中的暗場光束之示意圖。 圖4疋偏振77光單元對不同波長之p偏振光束的反 線圖。 圖5疋偏振分光單元對不同波長之$偏振光束的穿透率之曲 20 M339005 線圖。 圖6是本創作第二實施例之一種光學引擎的示意圖。 圖7是圖6之光學引擎中的暗場光束之示意圖。 圖8是分色單元對不同波長之P偏振光束及S偏振光束的反 射率之曲線圖。 【主要元件符號說明】 100、200、300 :光學引擎 110 :超高壓汞燈 112 :白色光束 • 112a :紅色部分光束 112b :綠色部分光束 112c :藍色部分光束 120 :光均勻化模組 122a、122b :透鏡陣列 124 :偏振轉換系統 126 :透鏡 130 :分合光系統 _ 132 ··分色單元 132a、132b、134 :分色鏡 . 136a、136b、136c :偏振分光稜鏡 138 : X棱鏡 140a、140b、140c :單晶矽液晶面板 150 :投影鏡頭 210、310 :光源模組 212b、312b :藍色光束 212r、312r :紅色光束 21 M339005 212g、312g :綠色光束 212b’、312b’ ：藍色影像光束 212r’、312r’ ：紅色影像光束 212g’、312g’ ：綠色影像光束 212f、312f :全彩影像光束 213b、313b :藍色暗場光束 213r、313r :紅色暗場光束 213g、313g:綠色暗場光束 - 214b、314b :第一同調光源 _ 214r、314r :第二同調光源 214g、314g :第三同調光源 220 ··偏振分光單元 230 :分色單元 240b、340b :第一光閥 240r、340r :第二光閥 240g、340g :第三光閥 250、350、370 :半波片 _ 260、360 :投影鏡頭 270 :透光體 280b、380b :第一濾光元件 280r、380r :第二濾光元件 280g、380g :第三濾光元件 320a ··第一偏振分光單元 322a :第一偏振分光部 320b :第二偏振分光單元 322b :第二偏振分光部 22 M339005 330a :第一分色單元 332a :第一分色部 330b :第二分色單元 332b :第二分色部Not intended to limit the scope of this creation. I [Simple Description of the Drawings] Fig. 1 is a schematic view of a conventional optical engine. 2 is a schematic view of an optical engine of the first embodiment of the present invention. Figure 3 is a schematic illustration of the dark field beam in the optical engine of Figure 2. Fig. 4 is an inverse diagram of a polarized 77 light unit for p-polarized beams of different wavelengths. Figure 5 is a plot of the transmittance of a polarized beam splitting unit for a polarized beam of different wavelengths. 20 M339005 line graph. Figure 6 is a schematic illustration of an optical engine of a second embodiment of the present invention. Figure 7 is a schematic illustration of a dark field beam in the optical engine of Figure 6. Figure 8 is a graph of the reflectance of a P-polarized beam and an S-polarized beam of different wavelengths by a color separation unit. [Main component symbol description] 100, 200, 300: optical engine 110: ultrahigh pressure mercury lamp 112: white light beam • 112a: red partial light beam 112b: green partial light beam 112c: blue partial light beam 120: light uniformization module 122a, 122b: lens array 124: polarization conversion system 126: lens 130: split light system _132 · color separation unit 132a, 132b, 134: dichroic mirror. 136a, 136b, 136c: polarization splitter 138: X prism 140a 140b, 140c: single crystal germanium liquid crystal panel 150: projection lens 210, 310: light source module 212b, 312b: blue light beam 212r, 312r: red light beam 21 M339005 212g, 312g: green light beam 212b', 312b': blue Image beams 212r', 312r': red image beams 212g', 312g': green image beams 212f, 312f: full color image beams 213b, 313b: blue dark field beams 213r, 313r: red dark field beams 213g, 313g: green Dark field beam - 214b, 314b: first coherent light source _ 214r, 314r: second coherent light source 214g, 314g: third coherent light source 220 · polarization splitting unit 230: color separation unit 240b, 340b: first light valve 240r, 340r: the first Two light valves 240g, 340g: third light valve 250, 350, 370: half wave plate _ 260, 360: projection lens 270: light transmitting body 280b, 380b: first filter element 280r, 380r: second filter element 280g, 380g: third filter element 320a · first polarization beam splitting unit 322a: first polarization beam splitting section 320b: second polarization beam splitting section 322b: second polarization beam splitting section 22 M339005 330a: first color separating unit 332a: a color separation portion 330b: a second color separation unit 332b: a second color separation portion