200814795 九、發明說明： 【發明所屬之技術領域】 本發明係關於一種用於液晶投影電視（Liquid Crystal Display Rear Projection Television，LCD RPTV)之圖像引擎（image engine,或稱光學機芯）， 尤其是一種適當增加紅光或藍光的成分來提高色溫、從而可增加亮度的LCD RPTV用之圖像引擎。 【先前技術】 LCD投影機按内部液晶板的片數可分為單片式和三片式兩種，美國專利 第6,669,343號即揭露了一種單片式LCD投影機用的圖像顯示系統3〇〇。如第 一圖所示，該圖像顯示系統3〇〇包括光源302,第一和第二積分器（Integrat〇r) 3〇4、3〇5，聚光透鏡（Condenser Lens ) 3〇7，分色裝置（Color Separating Means ) 350，非吸收性偏振元件（substantially Non_Absorptive Polarizing Element)326， 偏振光分束器（PolarizingBeam Splitter) 328，成像裝置（imager) 330，圖像 分析裝置（Analyzer) 332 和一個投影透鏡（projecti〇n Lens) 334。 光源302發出的非偏振光束經過第一和第二積分器3〇4、3〇5均勻化之後， 形成一光束；再由分色裝置350分成若干彩色光束；當這些彩色光束進入非吸 收性偏振元件326時，其中之P光透過，而S光則被反射、並被偏振光分束 器328導離成像裝置330 ;而偏振光分束器328將透過之p光導向成像裝置 33〇 ;成像裝置330實質是一種液晶顯示裝置，可對線性偏振光束進行調制使 之成像、並將成像光束反射回偏振光分束器328 ;偏振光分束器328將成像光 束中符合要求的部分導入圖像分析裝置332，經其進一步偏振後再入投影透鏡 5 200814795 ，334。最後’投影透鏡334將進一步偏振好的成像光束進行放大、並進行投影 顯示圖像。 另-種三片式LCD投影機則是用紅（Red，R)、綠（Green, G)、藍㈤此， B)二塊液晶板分別作為紅、綠、藍三色光的控制層。光源發射出來的白色光 經過鏡頭組後會聚到分色鏡組，紅色光首先被分離出來，投賴紅色液晶板 上’液晶板記錄”下的赠明絲示的圖像資訊被投射生成了圖像中的紅色 光貧訊。綠色光被投射麟色液晶板上，形細像巾麟色光資訊，同樣藍色 光經藍色液晶板後生成圖像中的藍色光資訊，三種顏色的絲稜鏡中會聚，由 投衫鏡頭投射到投影幕上形成-幅全彩色圖像。三片式LCD投影機比單片式 LCD投影機具有更高的圖像品質和更高的亮度。 ㈣實用新型專利第〇2217691·8號則公開了一種三片式背投電視(RpTV， Rear Projection Television)的光學機芯。它採用紹瓜氣體放電燈經反光鏡，產 生平行照明光束;再經兩塊複眼透鏡後由偏振轉換合成器轉換成單一偏振分量 (例如P光）的光束；再由二色分色鏡分色，反射出紅光，經反射鏡與透鏡 、 後射於紅色光路液晶片；二色分色鏡透射的光，由第二個二色分色鏡反射分 色出綠光，經透鏡照射至綠色光路液晶片；由第二個二色分色鏡分光後的藍光 ;過透鏡、反射鏡、透鏡、反射鏡以及透鏡之後照射到藍色光路液晶片；三束 光經二個液晶片調制後，形成三色圖像，再經過合色稜鏡，將三色光束合成一 束彩色圖像，經投影物鏡投影，由反射鏡投影成像於背投影螢幕上。 目月||在豕庭LCD RPTV中，白平衡趨向於高色溫（1〇〇⑻κ以上），由於 Lamp的色點和分光上的原因，LCDRPTV引擎在輪出最大亮度時色溫往 6 200814795 ，往偏低，這主要是藍光和紅光成分偏低，綠光成分偏高。爲了提高色溫，目前 應用背投電視三片式LCD光機中，往往是犧牲亮度來提高色溫（截去一部分 綠光和少部分的藍光或紅光），這樣將造成LCDRpTv亮度的偏低。 然而，爲了提高輸出光的強度，一種方法是提高燈泡的功#，另一種方法 是在相泡的辨下，使㈣衡設爲低色溫（如事務型投影機），這樣投影 機輸出亮度纽高色溫的投影機亮度增加。但對於背投電視來說，提高燈泡的 功率會降低燈泡的壽命，這種方案不可取；而背投電視因應市場需要趨向於較 同色溫，因此，背投電視的亮度會不得不因色點調整而偏低。 【發明内容】 本發明之目的在於提供一種用於液晶投影電視（LCDRPTV)之圖像引擎 (Image Engine)，其通過增加一或兩個高偏振態的藍色或紅色輔助雷射 (Laser)光源，來提高整個系統的色溫和亮度。 爲實現上述目的，本發明提供一種用於液晶投影裝置之圖像引擎，包括： 光源（Lamp)，發出非偏振光；輔助光源，發出輔助光束；偏振轉換合成裝置， 將光源發出的非偏振光和辅助光源發出的輔助光束合成加工為所需之偏振光 束，包括至少一個光積分器（Integrat〇r)、至少一個偏振光分束器（p〇larizing Beam Splitter，PBS)和至少一個聚光透鏡（c〇ndenserLens);光分色裝置，將 經偏振轉換合絲Ϊ加卫所得之偏振絲分成紅、藍、綠三路絲；和成像投 衫裝置，將經光分色裝置分出之紅、藍、綠三路光束分別經過對應之液晶裝置 進行調制後形成三色圖像，並經過相應之合色裝置將三色光束合成一束彩色圖 像’經投影裝置投影成像。 該輔助光源包括第一雷射（Laser)光源，可發出高偏振態藍色P光。該 200814795 -第-雷射光源包括至少-個第-齡透鏡（Expand Lens)和第一準直透鏡 (CoUimto Lens)，自第-雷射光源發出㈣射光束經第_擴束透鏡擴束 後，再經過第-準直透鏡，變成平行光束。該輔助光源還包括第二雷射光源， 可發出高偏振態紅色P光。該第二雷射光源包括至少一個第二擴束透鏡和第 -準直透鏡，自第二雷射光源發出的雷射光束經第二擴束透鏡擴束後，再經過 第二準直透鏡，變成平行光束。該辅助光源進一步包括—個二色鏡（Dichr〇ic Minw)，將從第一和第二準直透鏡出射的藍光和紅光合成一束光。 該偏振轉換合成裝置包括一個預偏振光分束器（Pre_p〇iari_ b_ Sphtter，Pre-PBS)，將自光源發出的非偏振光進行偏振化。該預偏振光分束器 包括A、B、C、D四個斜面和一個半波長薄片（Half Wavdength F〇il)。A、B、 C、D四個斜面分別於該預偏振光分束器的兩個相互平行的端面成45度角，a 和B斜面互相平行，C和D斜面互相平行，且B、c兩個斜面垂直相交於該 預偏振光分束器的光軸與其一個端面的交點上;該半波長薄片設於該預偏振光 分束器相對B、C兩個斜面交點之另一端面上，且位於B和c斜面之間。 從光源出射的光在光軸以上的部分經過B面後，p光透過，s光反射；p 光透射後，經過半波長薄片變成S光，從B面反射出來的S光經過A面反射 出去；從光源出射的光在光軸以下的部分經過C面後，P光透過，S光反射； P光透射後’經過半波長薄片變成S光，從c面反射出來的S光經過D面反 射出去。 該偏振轉換合成裝置還包括一個再合成-偏振光分束器 (Recombination-PBS)，將自上述輔助光源之二色鏡出射的光束和自上述預偏 8 200814795 <振光刀束器出射的光束合為一個光束並進一步偏振後，依次出射至上述之至少 個光積刀器、偏振光分束器和聚光透鏡。 ^光刀色裝置包括三個二色鏡，用於分別將最後自上述聚光透鏡中出射的 光束分成藍、紅、綠三色光束。 該圖像引擎還包括設置於光源和偏振轉換合成裝置之間的 UV/IR濾光 鏡，以渡去光源光束中之紫外線和紅外線。 【實施方式】 有關本發明液晶投影電視（LCDRpTv)之圖像引擎的詳細說明及技術内 谷，現即結合附圖說明如下： 請參閱第二圖，本發明一種用於液晶投影裝置之圖像引擎系統卜包括: 光源10 ’可發出非偏振光；輔助光源，用以發出輔助光束；偏振轉換合成裝 置將光源發出的非偏振光和輔助光源發出的辅助光束合成加工為所需之偏振 光束，包括-個預偏振光分束器40、再合成_偏振光分束器4卜兩個光積分器 42、43、-個偏振光分束器44和一個聚光透鏡45 ;光分色裝置，將經偏振轉 換合成裝置加工所得之傭光束分成多路具有不同波長範圍的光束，在本實施 例中係分成三路光束，分別具有第一波長範圍、第二波長範圍、第三波長範圍， 此三個波長範圍可岐紅、藍、綠三色（下文中將以紅、t、綠三色光為例說 明本發明，但可以瞭解，本發明亦可應用在此三色光以外的情形中，也可應用 在三路光細外❹路光束應财）；和成像投影裝置，將經光分色裝置分出 之紅、藍、綠三路光束分別經輯應讀晶裝置71進行欄後形成三色圖像， 並經過相應之合色裝置72將三色光束合成—束彩色圖像，經投影裝置73投影 成像。 9 200814795 . 輔助光源包括第一雷射光源12，可發出高偏振態藍色p光。該第一雷 射光源12包括兩個第一擴束透鏡⑵、122和第一準直透鏡⑵，自第一雷射 光源I2發出的雷射光束經第一擴束透鏡m⑵擴束後，再經過第一準直透 鏡，變成平行光束。該輔助光源還包括第二雷射光源^，可發出高偏振態 紅色P光。該第二雷射光源15包括兩個第二擴束透鏡⑸、⑸和第二準直 透鏡153，自第二雷射光源15發出的雷射光束經第二擴束透鏡⑸、⑸擴束 後，再經過第二準直透鏡153，變成平行光束。該辅助光源進一步包括一個二 色鏡16，將從第-和第二準直透鏡123、153出射的藍光和紅光合成一束光。 該偏振轉換合成裝置包括的預偏振光分束器4〇，將自光源1〇發出的非偏 振光進灯偏振化。如第三圖所示，該預偏振光分束^ 4()包括A、B、C、D四 個斜面和-個半波長薄片4〇2。A、B、c、D四個斜面分別於該預偏振光分束 器40的兩個相互平行的端面成45度角，a和B斜面互相平行，c和d斜面 互相平行’且B、C兩個斜面垂直相交於該預偏振光分束器的光軸與其一個端 面的交點上。該半波長薄片402設於該預偏振光分束器相對b、c兩個斜面交 點之另一端面上，且位於B和C斜面之間。 從光源出射的光在光軸以上的部分經過B面後，P光透過，S光反射；p 光透射後’經過半波長薄片402變成S光，從B面反射出來的S光經過A面 反射出去；從光源出射的光在光軸以下的部分經過C面後，p光透過，S光反 射；P光透射後，經過半波長薄片4〇2變成S光，從C面反射出來的S光則 經過D面反射出去。 該偏振轉換合成裝置的再合成_偏振光分束器41，將自上述輔助光源之二 200814795 射的光束和自上述預偏振光分束器4〇出射的光束合為一個光束並進 -步偏振化，依次_上述光_ 42、43、偏振光分束㈣和聚光透鏡 該光分色裝置包括三個二色锖 v t 巴鏡5卜52、53，用於分別將最後自上述聚光 透鏡45中出射的光束分成藍、紅、綠三色光束。 該圖像引擎1還包括設置於光源1〇和偏振轉換合成裝置之間的麵R遽 光鏡20，以滤去光源光束中之料線和紅外線4外，在光分色裝置與光成 像投影裝置之_設置了至少—個片⑼，以進_頻去紫外線。 從光源1〇出射的平行光經過刪尺遽光片2〇後，經過預偏振光分束器 40 ’此預偏振光分束器40的主要作用是使光源1〇 &來的光變成s光，這樣 做的主要目的是使光源1G發出的光和漏絲發出高偏振駿色或紅色p光 在再合成-偏振光分束器41上合成一束光。從第一和第二雷射光源12、15出 射的細光束，分別經過兩個擴束透鏡121、122及151、152擴束後，經過相應 的準直透鏡123、153後，變成平行光。而後，紅光和藍光在二色鏡16上合成 一束光。因爲自光源10和輔助光源12、15分別發出的光在光積分器42、43 之前合成一束光，此合成光經過兩個積分器42、43後被均勻的照射到液晶裝 置71上，此種結構不會影響光在液晶裝置71上亮度的均勻性。 而且，從光源1〇出射的光在偏振光分束器41之前經過了一次預偏振，這 樣從偏振光分束器41出來的光偏振度更高，此種結構還可以提高圖像引擎的 對比度。 採用此輔助光源前後，圖像引擎的輸出強度及色點如表1所示。 11 200814795 . 【圖式簡單說明】 第一圖係現有技術液晶投影機之圖像引擎之光學社構示音圖 第二圖係本發明液晶投影電視之圖像引擎之光學結構示音圖； 第三圖係本發明液晶投影電視之圖像引擎之預偏振光分束器（Pre_PBS) 之結構不意圖。 【主要元件符號說明】 1 圖像引擎 10 光源 20 UV/IR濾光片 12 第一雷射光源 12 卜 122 第一擴束透鏡 123 第一準直透鏡 15 第二雷射光源 153 第二準直透鏡 15 卜 152 第二擴束透鏡 16 一色鏡 40 預偏振光分束器 41 再合成-偏振光分束器 42、43 光積分器 44 偏振光分束器 45 聚光透鏡 5卜 52、53 二色鏡 60 UV濾光片 72合光裝置 71 液晶裝置 73 投影裝置 402 半波長薄片 13200814795 IX. Description of the Invention: [Technical Field] The present invention relates to an image engine (or optical engine) for a Liquid Crystal Display Rear Projection Television (LCD RPTV), in particular It is an image engine for LCD RPTV that appropriately increases the red or blue light component to increase the color temperature and thus increase the brightness. [Prior Art] The LCD projector can be divided into a single-chip type and a three-piece type according to the number of internal liquid crystal panels. An image display system for a single-chip LCD projector is disclosed in US Pat. No. 6,669,343. Hey. As shown in the first figure, the image display system 3 includes a light source 302, first and second integrators 3〇4, 3〇5, and a condenser lens (Condenser Lens) 3〇7. Color Separating Means 350, a substantially non-absorptive polarizing element 326, a Polarizing Beam Splitter 328, an imaging device 330, an image analyzing device (Analyzer) 332 and A projection lens (projecti〇n Lens) 334. The unpolarized light beam emitted by the light source 302 is homogenized by the first and second integrators 3〇4, 3〇5 to form a light beam; and then divided into a plurality of colored light beams by the color separation device 350; when the colored light beams enter a non-absorptive polarization In the case of element 326, the P light is transmitted, and the S light is reflected and guided away from the imaging device 330 by the polarization beam splitter 328; and the polarization beam splitter 328 directs the transmitted p light to the imaging device 33; 330 is essentially a liquid crystal display device that modulates a linearly polarized beam to image and reflects the imaged beam back to the polarizing beam splitter 328; the polarizing beam splitter 328 introduces the desired portion of the imaged beam into the image for analysis The device 332, after being further polarized, reenters the projection lens 5 200814795, 334. Finally, the projection lens 334 amplifies the further polarized imaging beam and projects the image. Another three-chip LCD projector uses red (R, R), green (Green), blue (five), and B) two LCD panels as the control layer for red, green, and blue light. The white light emitted by the light source passes through the lens group and then converges to the dichroic mirror group. The red light is first separated, and the image information of the bright silk screen under the 'liquid crystal panel recording' on the red liquid crystal panel is projected. The red light in the image is poor. The green light is projected on the lining LCD panel, and the shape is like a ray of light. The same blue light passes through the blue liquid crystal panel to generate blue light information in the image. The mid-convergence is projected from the projection lens onto the projection screen to form a full-color image. The three-chip LCD projector has higher image quality and higher brightness than the single-chip LCD projector. No. 22,276, 691 discloses an optical movement of a three-piece rear projection television (RpTV, Rear Projection Television) which uses a Saugua gas discharge lamp through a mirror to generate a parallel illumination beam; After being converted into a single polarization component (for example, P light) by a polarization conversion synthesizer; then separated by a dichroic dichroic mirror, reflected red light, passed through a mirror and a lens, and then incident on a red optical path liquid crystal; Color separation The light transmitted by the mirror is reflected by the second dichroic mirror to separate the green light, and is irradiated to the green light path liquid crystal through the lens; the blue light split by the second dichroic mirror; the lens, the mirror, The lens, the mirror and the lens are then irradiated to the blue light path liquid crystal film; after the three beams are modulated by the two liquid crystal chips, a three-color image is formed, and after the color combination, the three color light beams are combined into a color image. Projected by the projection objective, projected by the mirror on the rear projection screen. 目月||In the LCD LCD LCD RPTV, the white balance tends to a high color temperature (1 〇〇 (8) κ or more), due to the color point of the Lamp and the spectroscopic The reason is that the LCDRPTV engine has a color temperature of 6 200814795 when it is rotated for the maximum brightness, which is mainly due to the low blue and red light components and high green light composition. In order to improve the color temperature, the rear projection TV three-chip LCD light is currently applied. In the machine, it is often to sacrifice the brightness to increase the color temperature (cut off part of the green light and a small part of the blue or red light), which will cause the brightness of the LCDRpTv to be low. However, in order to increase the intensity of the output light, one way is to increase the light bulb. #,Another method is to discriminate the phase bubble, so that the (4) scale is set to a low color temperature (such as a transactional projector), so that the brightness of the projector output brightness high color temperature is increased. But for rear projection TV, Increasing the power of the bulb will reduce the life of the bulb. This solution is not desirable; while the rear projection TV tends to have a more similar color temperature in response to market demand, the brightness of the rear projection TV may have to be lowered due to color point adjustment. The object of the present invention is to provide an image engine for a liquid crystal projection television (LCDRPTV), which is improved by adding one or two high-polarization blue or red-assisted laser sources. The color temperature and brightness of the entire system. To achieve the above object, the present invention provides an image engine for a liquid crystal projection device, comprising: a light source (Lamp) that emits unpolarized light, an auxiliary light source that emits an auxiliary light beam, and a polarization conversion synthesizing device. Combining the unpolarized light from the light source and the auxiliary beam from the auxiliary source into a desired polarized beam, including at least one optical integrator (Integrat〇r a at least one polarizing beam splitter (PBS) and at least one concentrating lens (c〇ndenserLens); a light separating device that splits the polarizing filament obtained by polarizing the converted wire enthalpy into red , blue and green three-way wire; and the image-forming shirting device, the red, blue and green light beams separated by the light color separation device are respectively modulated by the corresponding liquid crystal device to form a three-color image, and correspondingly The color combining device combines the three color beams into a single color image 'projected through the projection device. The auxiliary light source includes a first laser source that emits a high polarization blue P light. The 200814795-the first laser source includes at least one first-stage lens (Expand Lens) and a first collimating lens (CoUimto Lens), and the (four)-beam emitted from the first-laser light source is expanded by the first-expansion lens Then, through the first collimating lens, it becomes a parallel beam. The auxiliary light source further includes a second laser light source that emits a high polarization red P light. The second laser light source includes at least one second beam expander lens and a first collimating lens, and the laser beam emitted from the second laser light source is expanded by the second beam expanding lens and then passed through the second collimating lens. Become a parallel beam. The auxiliary light source further includes a dichr mirror (Dichr〇ic Minw) that combines the blue light and the red light emitted from the first and second collimating lenses into one beam. The polarization conversion synthesizing device includes a pre-polarization beam splitter (Pre_p〇iari_b_Sphtter, Pre-PBS) that polarizes unpolarized light emitted from the light source. The pre-polarization beam splitter comprises four bevels of A, B, C, D and a half-wavelength sheet (Half Wavdength F〇il). The four inclined faces of A, B, C, and D are respectively at an angle of 45 degrees to the two mutually parallel end faces of the pre-polarized beam splitter, the a and B slopes are parallel to each other, the C and D slopes are parallel to each other, and B and c are respectively The inclined planes intersect perpendicularly to the intersection of the optical axis of the pre-polarization beam splitter and one end surface thereof; the half-wavelength sheet is disposed on the other end surface of the intersection of the two inclined planes of the pre-polarization beam splitter with respect to B and C, and Located between the B and c slopes. After the light emitted from the light source passes through the B-plane at the portion above the optical axis, the p-light is transmitted, and the s-light is reflected. After the p-light is transmitted, the S-light is reflected by the half-wavelength sheet, and the S-light reflected from the B-plane is reflected by the A-plane. When the light emitted from the light source passes through the C-plane at a portion below the optical axis, the P light is transmitted, and the S light is reflected. After the P light is transmitted, the S-light is reflected by the half-wavelength sheet, and the S-light reflected from the c-plane is reflected by the D-plane. Go out. The polarization conversion synthesizing device further includes a resynthesis-polarization beam splitter (Recombination-PBS), the light beam emitted from the dichroic mirror of the auxiliary light source and the light beam emitted from the pre-biased 8 200814795 < After being combined into one beam and further polarized, it is sequentially emitted to at least one of the above-mentioned optical fiber concentrator, polarization beam splitter and condensing lens. The light knife color device includes three dichroic mirrors for respectively splitting the light beams finally emitted from the above-mentioned condenser lens into blue, red and green light beams. The image engine also includes a UV/IR filter disposed between the light source and the polarization conversion synthesizer to absorb ultraviolet and infrared light from the source beam. [Embodiment] A detailed description and technical description of an image engine of a liquid crystal projection television (LCDRpTv) according to the present invention will now be described with reference to the accompanying drawings. Referring to the second figure, an image for a liquid crystal projection device of the present invention is shown. The engine system includes: a light source 10' emits unpolarized light; an auxiliary light source for emitting an auxiliary beam; and a polarization conversion synthesizing device that synthesizes the unpolarized light from the light source and the auxiliary beam from the auxiliary light source into a desired polarized beam, a pre-polarization beam splitter 40, a resynthesis_polarization beam splitter 4, two optical integrators 42, 43, a polarizing beam splitter 44, and a collecting lens 45; a light separating device, The laser beam processed by the polarization conversion synthesizing device is divided into a plurality of light beams having different wavelength ranges, and is divided into three light beams in the embodiment, and has a first wavelength range, a second wavelength range, and a third wavelength range, respectively. The three wavelength ranges may be three colors of magenta, blue, and green (hereinafter, the red, t, and green lights are exemplified as an example, but it can be understood that the present invention can also be applied to the three-color light. In other cases, it can also be applied to the three-way optical external beam path beam; and the imaging projection device, the red, blue and green light beams separated by the optical color separation device are respectively subjected to the crystal reading device A three-color image is formed after the column is performed, and the three-color light beam is combined into a color image by the corresponding color combining device 72, and projected and projected by the projection device 73. 9 200814795 . The auxiliary light source includes a first laser source 12 that emits a high polarization blue p light. The first laser light source 12 includes two first beam expanders (2), 122 and a first collimating lens (2), and the laser beam emitted from the first laser source I2 is expanded by the first beam expander m(2), and then After passing through the first collimating lens, it becomes a parallel beam. The auxiliary light source further includes a second laser source, which emits a high polarization red P light. The second laser source 15 includes two second beam expanding lenses (5), (5) and a second collimating lens 153. The laser beam emitted from the second laser source 15 is expanded by the second beam expanding lens (5), (5). Then, through the second collimating lens 153, it becomes a parallel beam. The auxiliary light source further includes a dichroic mirror 16 that combines the blue light and the red light emitted from the first and second collimating lenses 123, 153 into one beam. The polarization conversion synthesizing device includes a pre-polarization beam splitter 4 that polarizes the non-polarized light emitted from the light source 1 into the lamp. As shown in the third figure, the pre-polarized light splitting beam 4 () includes four slopes A, B, C, and D and a half-wavelength sheet 4〇2. The four slopes A, B, c, and D are respectively at an angle of 45 degrees to the two mutually parallel end faces of the pre-polarization beam splitter 40, and the a and B slopes are parallel to each other, and the c and d slopes are parallel to each other' and B, C The two inclined faces intersect perpendicularly to the intersection of the optical axis of the pre-polarized beam splitter and one of its end faces. The half-wavelength sheet 402 is disposed on the other end surface of the pre-polarization beam splitter opposite to the intersection of the two slopes b and c, and is located between the B and C slopes. After the light emitted from the light source passes through the B-plane at the portion above the optical axis, the P light is transmitted, and the S light is reflected. After the p-light transmission, the S-light is reflected by the half-wavelength sheet 402, and the S-light reflected from the B-plane is reflected by the A-plane. When the light emitted from the light source passes through the C-plane at a portion below the optical axis, the p-light is transmitted, and the S-light is reflected. After the P-light is transmitted, the S-light is reflected by the half-wavelength sheet 4〇2, and the S-light reflected from the C-plane is Reflected through the D surface. The resynthesis-polarization beam splitter 41 of the polarization conversion synthesizing device combines the light beam emitted from the second auxiliary light source 200814795 and the light beam emitted from the pre-polarization beam splitter 4〇 into one light beam and progressively polarized , in order to _ above-mentioned light _ 42, 43, polarized beam splitting (four) and concentrating lens, the light separating device comprises three dichromatic 锖 vt bar mirrors 5 52, 53 for respectively last from the above concentrating lens 45 The beam emitted in the middle is divided into three beams of blue, red and green. The image engine 1 further includes a surface R-mirror 20 disposed between the light source 1A and the polarization conversion synthesizing device to filter out the material line in the light source beam and the infrared light 4, in the light color separation device and the light imaging projection At least one piece (9) is provided for the device to remove ultraviolet rays. The parallel light emitted from the light source 1〇 passes through the cut-off pupil sheet 2, passes through the pre-polarization beam splitter 40'. The main function of the pre-polarization beam splitter 40 is to make the light from the light source 1〇& Light, the main purpose of doing this is to cause the light and the light emitted from the light source 1G to emit a high-polarization color or a red-p light to synthesize a beam of light on the resynthesis-polarizing beam splitter 41. The beamlets emitted from the first and second laser light sources 12, 15 are respectively expanded by the two beam expanding lenses 121, 122 and 151, 152, and then passed through the corresponding collimating lenses 123, 153 to become parallel light. Then, red light and blue light are combined to form a light beam on the dichroic mirror 16. Since the light respectively emitted from the light source 10 and the auxiliary light sources 12, 15 is combined with a light before the light integrators 42, 43, the synthesized light is uniformly irradiated onto the liquid crystal device 71 after passing through the two integrators 42, 43. The structure does not affect the uniformity of brightness of light on the liquid crystal device 71. Moreover, the light emitted from the light source 1〇 undergoes a pre-polarization before the polarization beam splitter 41, so that the polarization of the light from the polarization beam splitter 41 is higher, and the structure can also improve the contrast of the image engine. . Before and after using this auxiliary light source, the output intensity and color point of the image engine are shown in Table 1. 11 200814795 . The following is a schematic diagram of the optical structure of the image engine of the prior art liquid crystal projector. The second diagram is the optical structure of the image engine of the liquid crystal projection television of the present invention; The three figures are not intended to be a structure of a pre-polarization beam splitter (Pre_PBS) of an image engine of the liquid crystal projection television of the present invention. [Main component symbol description] 1 Image engine 10 Light source 20 UV/IR filter 12 First laser light source 12 Bu 122 First beam expander lens 123 First collimator lens 15 Second laser source 153 Second collimation Lens 15 152 second beam expander lens 16 color mirror 40 pre-polarization beam splitter 41 resynthesis - polarization beam splitter 42, 43 light integrator 44 polarization beam splitter 45 concentrating lens 5 52, 53 Color mirror 60 UV filter 72 light combining device 71 Liquid crystal device 73 Projecting device 402 Half wavelength sheet 13