CN201096990Y - optical engine - Google Patents

Abstract

An optical engine comprises a light splitting and combining system, wherein the light splitting and combining system comprises a first polarization light splitting unit, a color separation unit and a second polarization light splitting unit. The first color light beam incident from the light source side of the first polarization beam splitting unit is sequentially reflected by the first polarization beam splitting unit, reflected by the first light valve, and penetrates through the first polarization beam splitting unit. The second color light beam incident from the light source side sequentially penetrates through the first polarization beam splitting unit, is reflected by the second light valve and is reflected by the first polarization beam splitting unit to be combined with the first color light beam. The color separation unit is configured on the light path of the combined first color light beam and the second color light beam. The second polarization beam splitting unit is suitable for transmitting the third color light beam to the third light valve and transmitting the third color light beam reflected by the third light valve to the color separation unit. The color separation unit is suitable for combining the first color light beam, the second color light beam and the third color light beam.

Description

optical engine

technical field

The utility model relates to an optical engine, in particular to an optical engine using a coherent light source.

Background technique

Please refer to FIG. 1 , an existing optical engine 100 includes an ultra high pressure mercury lamp (ultra high pressure mercury lamp, UHP mercury lamp) 110, a light uniformizing module (light uniforming module) 120, and a beam splitting and combining system (beam splitting and combining system) 130. Three liquid crystal on silicon panels (liquid crystal on silicon panel, LCOS panel) 140a, 140b, 140c and a projection lens (projection lens) 150. The light homogenization module 120 includes two lens arrays (lens array) 122a, 122b, a polarization conversion system (polarization conversion system) 124 and a lens 126 . The light splitting system 130 includes a dichroic unit (dichroic unit) 132, a dichroic mirror (dichroic mirror) 134, three polarization beam splitting prisms (polarizing beam splitting prism, PBS prism) 136a, 136b, 136c and X prism (X cube) 138, wherein the dichroic unit 132 is composed of two dichroic mirrors 132a and 132b arranged to cross each other. The ultra-high pressure mercury lamp 110 is adapted to emit a white light beam 112 . The white light beam 112 has a single polarization direction after passing through the polarization conversion system 124 of the light homogenization module 120 .

The white light beam 112 can be considered to be composed of partial light beams with various wavelengths. The red part of the light beam 112a in the white light beam 112 will be reflected by the dichroic mirror 132a, reflected by the polarization beam splitter prism 136a, reflected by the single crystal silicon liquid crystal panel 140a, passed through the polarization beam splitter prism 136a, reflected by the X prism 138 and transmitted to the projector Lens 150. The green part of the light beam 112b in the white light beam 112 will be reflected by the dichroic mirror 132b, reflected by the dichroic mirror 134, reflected by the polarization beam splitter prism 136b, reflected by the single crystal silicon liquid crystal panel 140b, penetrating the polarization beam splitter prism 136b, and penetrating The X prism 138 and transmits to the projection lens 150 . The blue part of the light beam 112c in the white light beam 122 will be reflected by the dichroic mirror 132b in turn, penetrate the dichroic mirror 134, be reflected by the polarization beam splitter prism 136c, be reflected by the single crystal silicon liquid crystal panel 140c, pass through the polarization beam splitter prism 136c, and be reflected by the polarization beam splitter prism 136c. The X prism 138 reflects and transmits to the projection lens 150 .

In the existing optical engine 100 , since the light intensity of the white light beam 112 is reduced by about 15-20% after passing through the polarization conversion system 124 , the brightness of the video image provided by the optical engine 100 becomes lower. In addition, since the light emitting angle of the ultra-high pressure mercury lamp 110 is about 25°-30°, more lenses (such as lens arrays 112a, 112b, lens 126 and other lenses not shown) are required to converge the white light beam 112 , which makes the optical path traveled by the white light beam 112 longer, resulting in an increase in the volume of the optical engine 100 .

Utility model content

The utility model provides an optical engine, which has a relatively simplified structure, a small volume, and can provide video images with high brightness.

Embodiments of the present invention propose an optical engine, which includes a first light valve (light valve), a second light valve, a third light valve, a first coherent light source, a second coherent light source, a third coherent light source, and a split Synthetic light system. The first coherent light source is adapted to provide a first color light beam with a first polarization direction. The second coherent light source is adapted to provide a second color light beam with a second polarization direction. The third coherent light source is adapted to provide a third color light beam. The light splitting and combining system includes a first polarizing beam splitting unit (PBS unit), a color separation unit and a second polarizing beam splitting unit. The first color light beam incident from the light source side of the first polarization beam splitting unit and having the first polarization direction will be reflected by the first polarization beam splitting unit, reflected by the first light valve and pass through the first polarization beam splitting unit in sequence. The light beam of the second color incident from the light source side of the first polarization beam splitting unit and having the second polarization direction will sequentially pass through the first polarization beam splitting unit, be reflected by the second light valve, and be reflected by the first polarization beam splitting unit to be separated from the first color beam. Beam merging. The color separation unit is arranged on the light path of the combined first color light beam and the second color light beam from the first polarization light separation unit. The second polarization beam splitting unit is adapted to transmit the light beam having the third color to the third light valve, and is adapted to transmit the third color light beam reflected by the third light valve to the color separation unit. The color separation unit is suitable for combining the first, second and third color light beams into image beams.

In the embodiment of the present invention, it is disclosed that the first color light beam from the first coherent light source and the second color light beam from the second coherent light source will emerge from the first surface of the polarization beam splitting unit after being delivered to the polarization beam splitting unit, and The third color beam from the third coherent light source will exit from the second surface of the polarization beam splitting unit after being transmitted to the polarization beam splitting unit, wherein the third color beam emitted from the second surface will be reflected back to the second surface by the third light valve. surface. The color separation unit is arranged on the light path of the first color light beam and the second color light beam from the first surface. The first color light beam from the first surface will sequentially pass through the color separation unit, be reflected by the first light valve, pass through the color separation unit and return to the first surface, while the second color light beam from the first surface will be sequentially separated The cell reflects, is reflected by the second light valve, is reflected by the dichroic cell, and returns to the first surface. The first, second and third color light beams returning to the polarization beam splitting unit from the first, second and third light valves are combined into an image beam by the polarization beam splitting unit.

In the embodiment of the present invention, it is disclosed that the first color light beam from the first coherent light source and the second color light beam from the second coherent light source will be transmitted from the first color separation unit to the first color separation unit. surface, and the third color light beam from the third coherent light source will emerge from the second surface of the first color separation unit after being delivered to the first color separation unit. The first color light beam from the first color separation unit will be reflected by the first polarization beam splitting unit, reflected by the first light valve and pass through the first polarization beam splitting unit in sequence. The second color light beam from the first color separation unit sequentially passes through the first polarization beam splitting unit, is reflected by the second light valve, and is reflected by the first polarization beam splitting unit to merge with the first color beam. The second color separation unit is arranged on the light path of the combined first color light beam and the second color light beam from the first polarization light separation unit. The second polarization splitting unit is adapted to transmit the third color light beam from the first color separation unit to the third light valve, and is adapted to transmit the third color light beam reflected by the third light valve to the second color separation unit. The second color separation unit is suitable for combining the first, second and third color light beams into an image light beam.

The light splitting and combining system disclosed in the embodiment of the present invention uses two polarization splitting units and a color splitting unit to achieve the splitting and combining effect, and its structure is simpler than that of the prior art. In addition, in the optical engine, since the light beam emitted by the coherent light source is polarized light, the optical engine does not need to use a polarization conversion system, so the light intensity will not be lost due to the light beam passing through the polarization conversion system. In this way, the optical engine can provide images with higher brightness.

In order to make the above and other objects, features and advantages of the present invention more comprehensible, preferred embodiments will be described below in detail with reference to the accompanying drawings.

Description of drawings

FIG. 1 is a schematic structural diagram of a conventional optical engine.

Fig. 2 is a schematic structural view of the splitting and combining light system of the embodiment of the present invention.

Fig. 3 is a schematic structural diagram of a light splitting and combining system according to another embodiment of the present invention.

Fig. 4 is a schematic structural diagram of a light splitting and combining system according to another embodiment of the present invention.

FIG. 5 is a schematic structural diagram of an optical engine according to an embodiment of the present invention.

FIG. 6 is a schematic structural diagram of an optical engine according to another embodiment of the present invention.

FIG. 7 is a schematic structural diagram of an optical engine according to another embodiment of the present invention.

FIG. 8 is a schematic structural diagram of an optical engine according to yet another embodiment of the present invention.

FIG. 9 is a schematic structural diagram of an optical engine according to another embodiment of the present invention.

simple notation

50: First light valve

52, 62, 72: 1/4 wave plate

60: Second light valve

70: Third light valve

100, 300, 400, 400a, 400b, 500: optical engine

110: ultra-high pressure mercury lamp

112: white beam

112a: Red partial beam

112b: Green partial beam

112c: blue partial beam

120: Light homogenization module

122a, 122b: lens array

124: Polarization conversion system

126: lens

130, 200, 200a, 200b, 410, 410a, 410b, 510: split and combine light system

132, 222, 222', 432: color separation unit

132a, 132b, 134: dichroic mirrors

136a, 136b, 136c, 210, 230, 420, 530, 540: polarization beam splitter prism

138: X Prism

140a, 140b, 140c: monocrystalline silicon liquid crystal panel

150, 360: projection lens

212, 212', 532: the first polarization splitting unit

212a: light source side

214a, 214b, 224a, 224b, 234a, 234b, 424a, 424b, 434a, 434b, 464, 524a, 524b, 534a, 534b, 544a, 544b, 554a, 554b: Prisms

220, 430, 520, 550: dichroic prism

232, 232', 542: the second polarization splitting unit

310: The first coherent light source

320: Second coherent light source

330: The third coherent light source

340', 340a, 340b: optical modules

350: light-combining element

370a, 370b, 370c: wave plate

422, 422': polarization beam splitting unit

422a, 522a: first surface

422b, 522b: second surface

440, 450: prism body

460: reflective prism

462: Reflection Unit

522: The first color separation unit

552: Second color separation unit

B1, B1’, B1”: first color beam

B2, B2’, B2”: second color beam

B3, B3’, B3”: third color beam

D1, D1’, D1”: first polarization direction

D2, D2’, D2”: the second polarization direction

I, I’, I”: image beam

Detailed ways

The descriptions of the following embodiments refer to the accompanying drawings to illustrate specific embodiments that the present invention can be implemented in. The directional terms mentioned in the present invention, such as "up", "down", "front", "rear", "left", "right", etc., are only directions with reference to the accompanying drawings. Accordingly, the directional terms used are for illustration, not for limitation of the present invention.

Fig. 2 is a schematic structural view of the splitting and combining light system of the embodiment of the present invention. Referring to FIG. 2 , the light splitting and combining system 200 of this embodiment includes a first polarization splitting unit 212 , a color separation unit 222 and a second polarization splitting unit 232 . The first color light beam B1 incident on the light source side 212a of the first polarization beam splitting unit 212 and having the first polarization direction D1 will be reflected by the first polarization beam splitting unit 212, reflected by the first light valve 50 and pass through the first polarization beam splitting unit 212 in sequence. Unit 212. The second color light beam B2 incident on the light source side 212a of the first polarization beam splitting unit 212 and having the second polarization direction D2 will sequentially pass through the first polarization beam splitting unit 212, be reflected by a second light valve 60 and be split by the first polarization beam splitting unit 212. The unit 212 is reflected to merge with the first color light beam B1.

In this embodiment, the first polarization direction D1 may be substantially perpendicular to the second polarization direction D2. Specifically, the first polarization direction D1 and the second polarization direction D2 are, for example, the S polarization direction and the P polarization direction respectively, and the first light valve 50 and the second light valve 60 are, for example, single crystal silicon liquid crystal panels or other suitable reflective type light valve. The first color light beam B1 with the S polarization direction can be reflected by the first polarization splitting unit 212 to the first light valve 50 . Afterwards, the first color light beam B1 carries the image provided by the first light valve 50 and is reflected by the first light valve 50 into the first color light beam B1 with a P polarization direction. Then, the first color light beam B1 with the P polarization direction will pass through the first polarization splitting unit 212 . On the other hand, the second color light beam B2 with the P polarization direction can pass through the first polarization splitting unit 212 and be delivered to the second light valve 60 . Afterwards, the second color light beam B2 carries the image provided by the second light valve 60 and is reflected by the second light valve 60 into the second color light beam B2 with S polarization direction. Next, the second color light beam B2 with the S polarization direction is reflected by the first polarization splitting unit 212 and merged with the first color light beam B1. In other embodiments, the first polarization direction D1 and the second polarization direction D2 may also be the P polarization direction and the S polarization direction, or other appropriate polarization directions.

The color separation unit 222 is disposed on the light path of the combined first color beam B1 and the second color beam B2 from the first polarization beam splitter unit 212 . The second polarization beam splitting unit 232 is adapted to transmit the third color beam B3 to the third light valve 70 , and is adapted to transmit the third color beam B3 reflected by the third light valve 70 to the color separation unit 222 . The color separation unit 222 is adapted to combine the first, second and third color light beams B1, B2, B3 into an image light beam I.

In this embodiment, the polarization direction of the third light beam B3 is the same as the first polarization direction D1. Specifically, the polarization direction of the third light beam B3 is, for example, the S polarization direction. The third color light beam B3 with the S polarization direction will be reflected by the second polarization splitting unit 232 to the third light valve 70 . Afterwards, the third color light beam B3 will carry the image provided by the third light valve 70 and be reflected by the third light valve 70 into the third color light beam B3 with a P polarization direction, wherein the third light valve 70 is, for example, a single crystal silicon LCD panel or other suitable reflective light valve. Next, the third color light beam B3 with the P polarization direction will pass through the second polarization splitting unit 232 and be delivered to the color separation unit 222 . The first color light beam B1 and the third color light beam B3 may be respectively incident from opposite sides of the color separation unit 222 . In addition, in this embodiment, the color separation unit 222 is suitable for allowing the first color light beam B1 and the second color light beam B2 to pass through, and is suitable for reflecting the third color light beam B3. Therefore, the color separation unit 222 can combine the first, second and third color light beams B1, B2, B3 into an image light beam I. However, in other embodiments, the color separation unit can also reflect the first color light beam B1 and the second color light beam B2, and allow the third color light beam B3 to pass through, so that the first, second and third color light beams can also be achieved. The combined effect of color light beams B1, B2, B3.

In addition, in other embodiments, the polarization direction of the third light beam B3 may also be the same as the second polarization direction D2 or may be other appropriate directions. For example, in another embodiment, the polarization direction of the third light beam B3 is, for example, the P polarization direction, and the third color light beam with the P polarization direction can sequentially pass through the second polarization splitting unit 232 and be absorbed by the third light valve. 70 is reflected as a third color light beam with S polarization direction. Next, the third color light beam with the S polarization direction is reflected by the second polarization splitting unit 232 to the color splitting unit 222 .

In this embodiment, the light splitting and combining system 200 may further include two prisms 214a and 214b, which respectively lean against opposite sides of the first polarization splitting unit 212 . One of these prisms (ie, prism 214a) is located on the light path between the first polarization beam splitting unit 212 and the first light valve 50, while the other prism (ie, prism 214b) is located between the first polarization beam splitting unit 212 and the second light beam. on the light path between valve 60. The first polarization beam splitting unit 212 is, for example, a polarization beam splitting film, and the prism 214 a , the prism 214 b and the first polarization beam splitting unit 212 can constitute a polarization beam splitting prism 210 .

In addition, the splitting and combining system 200 may further include two prisms 224a and 224b, which are supported on opposite sides of the color separation unit 222 respectively. One of these prisms (i.e. prism 224a) is located on the light path between the first polarization splitting unit 212 and the color separation unit 222, and the other prism (i.e. prism 224b) is located between the color separation unit 222 and the second polarization division unit 232 on the light path between. The dichroic unit 222 is, for example, a dichroic film, and the prism 224 a , the prism 224 b and the dichroic unit 222 can constitute the dichroic prism 220 .

In addition, the splitting and combining system 200 may further include two prisms 234a and 234b, which respectively lean against opposite sides of the second polarization splitting unit 232 . One of these prisms (ie, the prism 234 a ) is located on the light path between the color separation unit 222 and the second polarization separation unit 232 . The second polarization beam splitting unit 232 is, for example, a polarization beam splitting film, and the prism 234 a , the prism 234 b and the second polarization beam splitting unit 232 can constitute the polarization beam splitting prism 230 . In this embodiment, the third light valve 70 may be disposed near the side of the prism 234b, but in other embodiments, the third light valve 70 may also be disposed near the side of the prism 234a.

In this embodiment, one of the first to third color light beams B1-B3 is, for example, a red light beam, the other color light beam is, for example, a green light beam, and the remaining color light beams are, for example, blue light beams. In this way, the first to third color light beams B1-B3 can be combined into image light beams I with various colors. In addition, in order to improve the contrast of the image light beam I, the first to third color light beams B1-B3 can pass through the quarter-wave plates 52, 62, and 72 respectively before entering the first to third light valves 50-70. And after being reflected by the first to third light valves 50-70, it passes through the 1/4 wave plates 52, 62, 72 again.

Based on the above, the splitting and combining system 200 of this embodiment adopts two polarization splitting units (i.e. the first and second polarizing splitting units 212, 232) and the color separation unit 222 to achieve the splitting and combining effect, so compared with the prior art , the structure of the splitting and combining optical system 200 is relatively simplified. In this way, the light splitting and combining system 200 can be smaller in size and lower in cost. In addition, the light splitting system 200 of this embodiment can be applied to an optical engine with a coherent light source.

It should be noted that the present invention does not limit that the first and second polarization splitting units 212 , 232 and the color separation unit 222 are arranged in the form of a film at the junction of the two prisms. In other embodiments, at least one of the first polarization splitting unit 212 , the second polarization splitting unit 232 and the color separation unit 222 may be in the shape of a plate, and its shape and position may not be fixed by a prism. The following will take two embodiments as representatives to describe in detail.

Fig. 3 is a schematic structural diagram of a light splitting and combining system according to another embodiment of the present invention. Please refer to Fig. 3, the splitting and combining light system 200a of the present embodiment is similar to the above-mentioned splitting and combining light system 200 (please refer to Fig. It is in the shape of a plate, and the two sides of the color separation unit 222' can be fixed without disposing prisms. For example, the color separation unit 222' is a dichroic mirror.

Fig. 4 is a schematic structural diagram of a light splitting and combining system according to another embodiment of the present invention. Please refer to FIG. 4 , the splitting and combining optical system 200b of the present embodiment is similar to the aforementioned splitting and combining optical system 200 (please refer to FIG. 2 ), the difference between the two is that in the splitting and combining optical system 200b, the first polarization splitting unit 212 ' and the second polarization splitting unit 232' can be plate-shaped, and the two sides of these polarization splitting units can be fixed without prisms. For example, the first polarization splitting unit 212' and the second polarization splitting unit 232' are, for example, wire grid type polarizing beam splitters.

FIG. 5 is a schematic structural diagram of an optical engine according to an embodiment of the present invention. Please refer to FIG. 5 , the optical engine 300 of this embodiment includes the above-mentioned first light valve 50, the above-mentioned second light valve 60, the above-mentioned third light valve 70, the first coherent light source 310, the second coherent light source 320, the third coherent light source The light source 330 and the above-mentioned splitting and combining light system 200 . The first coherent light source 310 is adapted to provide the above-mentioned first color light beam B1 having the first polarization direction D1. The second coherent light source 320 is adapted to provide the above-mentioned second color light beam B2 having the second polarization direction D2. The third coherent light source 330 is adapted to provide the above-mentioned third color light beam B3.

In this embodiment, the first, second and third coherent light sources 310 , 320 , 330 are, for example, laser light sources. In addition, the first, second and third color light beams B1, B2, B3 emitted by the first, second and third coherent light sources 310, 320, 330 can be passed through the optical system 200 before entering the optical splitting system 200. Module (optical module), to change the shape of the first to third color light beams B1~B3 and to make the first to third color light beams B1~B3 uniform, or to make the first to third color light beams B1~B3 reach other optical Effect. Specifically, the first color light beam B1 and the second color light beam B2 may pass through the optical module 340a, and the third color light beam B3 may pass through the optical module 340b. The optical modules 340a and 340b may include lenses, lens arrays, diffraction optical elements (DOEs), integration rods, other suitable optical elements, or any combination of these elements.

In addition, the first color light beam B1 and the second color light beam B2 from the first coherent light source 310 and the second coherent light source 320 can first be combined by a beam combining element 350, so that the two light beams are simultaneously emitted by the light source The side 212a is incident to the first polarization splitting unit 212 . In this embodiment, the light combining element 350 is, for example, a dichroic mirror. However, in other embodiments, the light combining element 350 may also be a dichroic prism, an X prism or other suitable light combining elements. In addition, in this embodiment, a projection lens 360 may be arranged on the optical path of the image beam I emitted by the color separation unit 222, so that the image beam I is projected onto a screen (not shown) to form an image image.

In this embodiment, the first to third color light beams B1 to B3 emitted by the first to third coherent light sources 310 to 330 can respectively pass through wave plates 370a, 370b and 370c before entering the splitting and combining optical system 200 . By rotating the wave plates 370a, 370b, 370c, the polarization directions of the first to third color beams B1-B3 can be adjusted, wherein the wave plates 370a, 370b, 370c are, for example, half-wave plates. However, in other embodiments, the polarization directions of the first to third color beams B1 to B3 can also be adjusted by directly rotating the first to third coherent light sources 310 to 330 without making the first to third color beams B1 ~B3 passes through the wave plates 370a, 370b and 370c.

Based on the above, in the optical engine 300 of this embodiment, due to the light beams (such as the first, second and third color light beams) emitted by the coherent light sources (such as the first, second and third coherent light sources 310, 320, 330) B1, B2, B3) are polarized light, so the optical engine 300 does not need to use a polarization conversion system to polarize the light beam, so the light intensity will not be lost due to the light beam passing through the polarization conversion system. In this way, the optical engine 300 of this embodiment can provide an image with higher brightness.

In addition, due to the good collimation of the coherent light source, the divergence angle of the beam emitted by the coherent light source is very small, so this embodiment does not need to use many mirrors to converge the beam. In this way, the optical path of the light beam traveling in the optical engine 300 can be shortened, thereby reducing the volume of the optical engine 300 . When the optical engine 300 is applied to a rear projection television (RPTV), the thickness of the rear projection television can be reduced. Furthermore, since the optical engine 300 uses a coherent light source with good collimation, the design of the beam divergence angle in this embodiment has greater flexibility.

In addition, since the structure of the splitting and combining system 200 is simpler than that of the existing splitting and combining systems, and the optical engine 300 of this embodiment does not need to use a polarization conversion unit, nor does it need to use many lenses to converge the light beams to the splitting and combining lights. The cost of the system 200, and thus the optical engine 300 of this embodiment is relatively low.

It is worth noting that the present invention does not limit the optical splitting and combining system adopted by the optical engine to be the aforementioned splitting and combining optical system 200 . In other embodiments, the optical engine may also adopt the optical splitting and combining systems of other embodiments above, such as the splitting and combining optical systems 200a, 200b, and the like.

FIG. 6 is a schematic structural diagram of an optical engine according to another embodiment of the present invention. The optical engine 400 of this embodiment is partially similar to the above-mentioned optical engine 300 (please refer to FIG. 5 ). A first color light beam B1' with a polarization direction D1'. The second coherent light source 320 is adapted to provide a second color light beam B2' having a first polarization direction D1'. The third coherent light source 330 is adapted to provide a third color light beam B3' having a second polarization direction D2'. In addition, in this embodiment, the splitting and combining light system 410 is used to replace the aforementioned splitting and combining light system 200 (please refer to FIG. 5 ).

The splitting and combining system 410 includes a polarization splitting unit 422 and a color splitting unit 432 . After the first color light beam B1' from the first coherent light source 310 and the second color light beam B2' from the second coherent light source 320 are transmitted to the polarization beam splitting unit 422, they will emerge from the first surface 422a of the polarization beam splitting unit 422, and The third color light beam B3 ′ from the third coherent light source 330 will exit from the second surface 422 b of the polarization beam splitting unit 422 after being delivered to the polarization beam splitting unit 422 . In this embodiment, the first polarization direction D1' may be substantially perpendicular to the second polarization direction D2'. Specifically, the first polarization direction D1' is, for example, the S polarization direction, and the second polarization direction D2' is, for example, the P polarization direction. In this embodiment, the first color light beam B1' and the second color light beam B2' having the S polarization direction can enter the polarization beam splitting unit 422 from the first surface 422a, and after being reflected by the polarization beam splitting unit 422, the polarization beam splitting unit 422 The first surface 422a exits. In addition, the third color light beam B3' having the P polarization direction can enter the polarization beam splitting unit 422 from the first surface 422a, pass through the polarization beam splitting unit 422 and exit from the second surface 422b of the polarization beam splitting unit 422. However, in other embodiments, the first polarization direction D1' and the second polarization direction D2' may also be the P polarization direction and the S polarization direction respectively, and the first color light beam B1' and the second color light beam B2' may also be The third color beam B3 ′ passes through the polarization beam splitting unit 422 and may also be reflected by the polarization beam splitting unit 422 . In this embodiment, the third color light beam B3' emitted from the second surface 422b will be reflected by the third light valve 70 back to the second surface 422b.

The color separation unit 432 is disposed on the light path of the first color light beam B1' and the second color light beam B2' from the first surface 422a. The first color light beam B1' from the first surface 422a will sequentially pass through the color separation unit 432, be reflected by the first light valve 50, pass through the color separation unit 432 and return to the first surface 422a, while the first color beam B1' from the first surface 422a The dichroic light beam B2' is sequentially reflected by the color separation unit 432, reflected by the second light valve 60, reflected by the color separation unit 432, and returns to the first surface 422a. The first, second and third color light beams B1', B2', B3' returning to the polarization beam splitting unit 422 from the first to third light valves 50-70 are combined by the polarization beam splitting unit 422 into an image beam I'.

Specifically, after the first color light beam B1' with S polarization is reflected by the first light valve 50, it carries the image provided by the first light valve 50 and is converted into the first color light beam B1' with P polarization. Thereafter, the first color light beam B1' with the P polarization direction returns to the first surface 422a, passes through the polarization beam splitting unit 422 and exits from the second surface 422b. On the other hand, after the second color light beam B2' with S polarization direction is reflected by the second light valve 60, it will carry the image provided by the second light valve 60 and transform into the second color light beam B2' with P polarization direction. Thereafter, the second color light beam B2' having the P polarization direction returns to the first surface 422a, passes through the polarization beam splitting unit 422 and exits from the second surface 422b. In addition, after the third color light beam B3' with P polarization direction is reflected by the third light valve 70, it will carry the image provided by the third light valve 70 and transform into the third color light beam B3' with S polarization direction. Thereafter, the third color light beam B3' is incident on the second surface 422b, reflected by the polarization splitting unit 422, and exits from the second surface 422b. At the same time, the first, second and third color light beams B1', B2' and B3' emitted from the second surface 422b are merged into an image light beam I'.

In this embodiment, the light splitting and combining system 410 may further include two prisms 424a and 424b, which respectively lean against opposite sides of the polarization splitting unit 422 . One of these prisms (ie prism 424a) is located on the light path between the polarization beam splitting unit 422 and the third light valve 70, and the other prism (ie prism 424b) is located between the polarization beam splitting unit 422 and the color separation unit 432 on the light path. The polarization beam splitting unit 422 is, for example, a polarization beam splitting film, and the polarization beam splitting unit 422 , the prism 424 a and the prism 424 b can constitute the polarization beam splitting prism 420 .

On the other hand, the light splitting and combining system 410 may further include two prisms 434a and 434b, which respectively lean against opposite sides of the color separation unit 432 . One of these prisms (ie, prism 434a) is located on the light path between the dichroic unit 432 and the first light valve 50, while the other prism (ie, prism 434b) is located between the dichroic unit 432 and the second light valve 60 on the light path. The dichroic unit 432 is, for example, a dichroic film, and the dichroic unit 423 , the prism 434 a and the prism 434 b can constitute the dichroic prism 430 .

In order to make the optical distance from the third light valve 70 to the projection lens 360 close to the optical distance from the first and second light valves 50, 60 to the projection lens 360, the light between the third light valve 70 and the polarization splitting unit 422 A prism body 440 is selectively arranged on the path, wherein the shape of the prism body 440 may be similar to that of the polarizing beam splitting prism 420 or the dichroic prism 430 . However, in the optical engine of other embodiments, the prism body 440 may not be used, but a certain distance between the third light valve 70 and the polarization splitting unit 422 may be maintained, so as to achieve the above-mentioned effects of similar optical distances.

In addition, the optical engine 400 of this embodiment may further include an optical module 340 ′, which is arranged on the optical path between the first to third coherent light sources 310 - 330 and the splitting optical system 410 to change the first to third The shape of the color light beams B1'-B3' and the uniformization of the first to third color light beams B1'-B3', or the first to third color light beams B1'-B3' to achieve other optical effects. The components of the optical module 340' can be the same as the above-mentioned optical modules 340a, 340b (please refer to FIG. 5 ).

The optical engine 400 of this embodiment also has the function of the above-mentioned optical engine 300 (please refer to FIG. 5 ), and will not be repeated here. In addition, it should be noted that, in other embodiments, at least one of the polarization splitting unit and the color splitting unit may be in the shape of a plate, and the shape and position may not be fixed by a prism. When the polarization beam splitting unit is in the shape of a plate, the polarization beam splitting unit may be a grid-shaped polarization beam splitting plate. When the color separation unit is plate-shaped, the color separation unit may be a dichroic mirror. Hereinafter, an embodiment will be taken as a representative to describe in detail.

FIG. 7 is a schematic structural diagram of an optical engine according to another embodiment of the present invention. Referring to FIG. 7, the optical engine 400a of this embodiment is similar to the above-mentioned optical engine 400 (please refer to FIG. 6). It is in the shape of a plate, and the two sides of the polarization beam splitting unit 422' can be fixed without disposing prisms. In addition, the splitting and combining optical system 410a may further include a prism body 450 connected to the prism body 440 and the dichroic prism 430 to improve the alignment accuracy of the splitting and combining optical system 410a.

FIG. 8 is a schematic structural diagram of an optical engine according to yet another embodiment of the present invention. Please refer to FIG. 8 , the optical engine 400b of the present embodiment is similar to the above-mentioned optical engine 400 (please refer to FIG. 6), instead, the splitting and combining optical system 410b includes a reflecting unit 462, which is arranged on the optical path of the third color light beam B3', and is located between the polarization splitting unit 422 and the third light valve 70, so as to separate the first The three-color light beam B3 ′ is reflected to the third light valve 70 . In addition, the splitting and combining optical system 410b may further include a prism 464, which bears against one side of the reflecting unit 462 and is located on the light path of the third color light beam B3'. The reflective unit 462 is, for example, a reflective film, and the reflective unit 462 and the prism 464 can form a reflective prism 460 . However, in other embodiments, the reflective unit may also be in the shape of a plate, and may not be fixed by a prism disposed on one side thereof, that is, the reflective unit may also be a reflective mirror.

FIG. 9 is a schematic structural diagram of an optical engine according to another embodiment of the present invention. Please refer to FIG. 9 , the optical engine 500 of this embodiment is partially similar to the above-mentioned optical engine 400 (please refer to FIG. 6 ), the difference between the two lies in: in the optical engine 500 of this embodiment, the first coherent light source 310 It is adapted to provide a first color light beam B1 ″ having a first polarization direction D1 ″. The second coherent light source 320 is adapted to provide a second color light beam B2 ″ having a second polarization direction D2 ″. The third coherent light source 330 is suitable for providing the third color beam B3 ″. In addition, in this embodiment, the above-mentioned splitting and combining system 410 is replaced by the splitting and combining system 510 (please refer to FIG. 6 ).

The light separation and combination system 510 includes a first color separation unit 522 , a first polarization separation unit 532 , a second polarization separation unit 542 and a second color separation unit 552 . After the first color light beam B1 ″ from the first coherent light source 310 and the second color light beam B2 ″ from the second coherent light source 320 are transmitted to the first color separation unit 522 , they will pass from the first surface of the first color separation unit 522 522a, and the third color light beam B3" from the third coherent light source 330 will emerge from the second surface 522b of the first color separation unit 522 after being delivered to the first color separation unit 522. Specifically, in this implementation In this example, the first to third color light beams B1 ″˜ B3 ″ can all be incident from the second surface 522b of the first color separation unit 522. The first color separation unit 522 is suitable for allowing the first and second color light beams B1 ″, B2" penetrates and emerges from the first surface 522a, and the first dichroic unit 522 is adapted to reflect the third color beam B3" so that the third color beam B3" emerges from the second surface 522b. However, in other embodiments , the first color separation unit can also reflect the first and second color light beams B1 ″, B2 ″, and allow the third color light beam B3 ″ to pass through.

The first color light beam B1 ″ from the first color separation unit 522 will be reflected by the first polarization beam separation unit 532 in turn, reflected by the first light valve 50 and penetrate the first polarization beam separation unit 532. The light beam B1″ from the first color separation unit 522 The second color light beam B2" will sequentially pass through the first polarization beam splitting unit 532, be reflected by the second light valve 60, and be reflected by the first polarization beam splitting unit 532 to merge with the first color beam B1". The second color separation unit 552 is configured On the optical path of the combined first color light beam B1 ″ and second color light beam B2 ″ from the first polarization splitting unit 532 .

In this embodiment, the first polarization direction D1 ″ may be substantially perpendicular to the second polarization direction D2 ″. Specifically, the first polarization direction D1 ″ is, for example, the S polarization direction, and the second polarization direction D2 ″ is, for example, the P polarization direction. The first color light beam B1 ″ having the S polarization direction will be reflected by the first polarization beam splitting unit 532 to the first light valve 50. Then, the first color light beam B1 ″ will carry the image provided by the first light valve 50 and be captured by the first light valve 50. The light valve 50 reflects the first color light beam B1 ″ with P polarization direction. Afterwards, the first color light beam B1 ″ with P polarization direction passes through the first polarization splitting unit 532 and is transmitted to the second color separation unit 552 . On the other hand, the second color light beam B2 ″ having the P polarization direction will pass through the first polarization beam splitting unit 532 and be delivered to the second light valve 60. Then, the second color light beam B2 ″ will carry the light provided by the second light valve 60 and is reflected by the second light valve 60 into the second color light beam B2 ″ with the S polarization direction. Afterwards, the second color light beam B2 ″ with the S polarization direction will be reflected by the first polarization splitting unit 532 to the second color separation Unit 552. However, in other embodiments, the first polarization direction and the second polarization direction may also be the P polarization direction and the S polarization direction respectively.

The second polarization splitting unit 542 is adapted to transmit the third color light beam B3 ″ from the first color separation unit 522 to the third light valve 70, and is adapted to pass the third color light beam B3 ″ reflected by the third light valve 70 To the second color separation unit 552. In this embodiment, the polarization direction of the third light beam B3 may be the same as the first polarization direction D1". Specifically, the polarization direction of the third light beam B3 is, for example, the S polarization direction. It comes from the first dichroic unit 522 and has S The third color light beam B3 ″ in the polarization direction can be reflected by the second polarization splitting unit 522 to the third light valve 70 . Next, the third color light beam B3 ″ carries the image of the third light valve 70 and is reflected by the third light valve 70 into the third color light beam B3 ″ having a P polarization direction. Afterwards, the third color light beam B3 ″ having the P polarization direction will pass through the second polarization splitting unit 542 and be transmitted to the second color separation unit 552 .

In other embodiments, the polarization direction of the third light beam B3 may also be the same as the second polarization direction or other appropriate polarization directions. For example, the polarization direction of the third light beam B3 is, for example, the P polarization direction, and the third color light beam can sequentially pass through the second polarization beam splitting unit 542, be reflected by the third light valve 70, and be reflected by the second polarization beam splitting unit 542 to The second color separation unit 552 .

In this embodiment, the second color separation unit 552 is adapted to combine the first, second and third color light beams B1 ″, B2 ″, B3 ″ into an image light beam I″. Specifically, in this embodiment, the second color separation unit 552 allows the first color light beam B1 ″ and the second color light beam B2 ″ to pass through, and reflects the third color light beam B3 ″, so that the first to the second color light beams The three-color light beams B1 ″˜ B3 ″ are merged into an image light beam I ″. However, in other embodiments, the second color separation unit can also allow the third color beam B3 ″ to penetrate, and reflect the first color beam B1 ″ and the second color beam B2 ″, so that the first color beam B3 ″ can also be achieved. To the effect that the third color light beams B1 ″˜B3 ″ are merged into an image light beam I ″.

In this embodiment, the light splitting and combining system 510 may further include two prisms 524a and 524b, which are supported on opposite sides of the first dichroic unit 522 respectively. One of these prisms (ie prism 524a) is located on the light path between the second polarization beam splitting unit 542 and the first color separation unit 522, and the other prism (ie prism 524b) is located between the first polarization beam splitting unit 532 and the first color separation unit 522. On the light path between the color separation units 522 . The first dichroic unit 522 is, for example, a dichroic film, and the first dichroic unit 522 , the prism 524 a and the prism 524 b can constitute a dichroic prism 520 .

In addition, the light splitting and combining system 510 may further include two prisms 534a and 534b, which respectively lean against opposite sides of the first polarization splitting unit 532 . One of these prisms (i.e. prism 534a) is located on the light path between the first dichroic unit 522 and the first polarization division unit 532, while the other prism (i.e. prism 534b) is located between the second dichroic unit 552 and the first polarization division unit 532. on the light path between the polarization splitting units 532 . The first polarization beam splitting unit 532 is, for example, a polarization beam splitting film, and the first polarization beam splitting unit 532 , the prism 534 a and the prism 534 b can constitute a polarization beam splitting prism 530 .

Furthermore, the light splitting and combining system 510 may further include two prisms 554a and 554b, which respectively bear against opposite sides of the second color separation unit 552 . One of these prisms (ie, prism 554a) is located on the light path between the first polarization beam splitting unit 532 and the second color separation unit 552, and the other prism (ie, prism 554b) is located between the second polarization beam splitting unit 542 and the second color separation unit 542. On the light path between the color separation units 552 . The second dichroic unit 552 is, for example, a dichroic film, and the second dichroic unit 552 , the prism 554 a and the prism 554 b can constitute a dichroic prism 550 .

In addition, the splitting and combining system 510 may further include two prisms 544a and 544b, which respectively lean against opposite sides of the second polarization splitting unit 542 . One of these prisms (i.e. prism 544a) is located on the light path between the first dichroic unit 522 and the second polarization division unit 542, while the other prism (i.e. prism 544b) is located between the second dichroic unit 552 and the second polarization unit 542. on the light path between the polarization splitting units 542 . The second polarization beam splitting unit 542 is, for example, a polarization beam splitting film, and the second polarization beam splitting unit 542 , the prism 544 a and the prism 544 b can constitute a polarization beam splitting prism 540 .

The optical engine 500 of this embodiment also has the function of the above-mentioned optical engine 300 (please refer to FIG. 5 ), and will not be repeated here. In addition, it is worth noting that in other embodiments, at least one of the first dichroic unit, the second dichroic unit, the first polarized beam-splitter unit, and the second polarized beam-splitter unit may be in the shape of a plate, and may not need to pass through Prism to fix its shape and position. When the first and second polarizing beam splitting units are plate-shaped, the first and second polarizing beam splitting units may be grid-shaped polarizing beam splitting plates. When the first and second dichroic units are plate-shaped, the first and second dichroic units may be dichroic mirrors.

To sum up, compared with the prior art, the structure of the light splitting and combining system of the present invention is simpler, so the volume of the splitting and combining light system of the present utility model is smaller and the cost is lower. In addition, the light splitting and combining system of the present invention can be applied to an optical engine with a coherent light source. In the optical engine of the utility model, since the beam emitted by the coherent light source is polarized light, the utility model does not need to use a polarization conversion system to polarize the beam, so the beam will not cause light intensity due to passing through the polarization conversion system. Loss. In this way, the optical engine of the present invention can provide images with higher brightness.

In addition, due to the good collimation of the coherent light source, the divergence angle of the beam emitted by the coherent light source is very small, so the utility model does not need to use many mirrors to converge the beam. In this way, the optical path of the light beam traveling in the optical engine can be shortened, thereby reducing the volume of the optical engine of the present invention. Furthermore, since the optical engine of the present invention adopts a coherent light source with good collimation, the present invention has greater flexibility in designing the beam divergence angle.

In addition, since the structure of the light splitting and combining system of the present invention is simpler than that of the existing splitting and combining systems, and the optical engine of the present utility model does not need to use a polarization conversion unit, nor does it need to use many lenses to converge the light beam to Combining optical systems, so the cost of the optical engine of the utility model is relatively low.

Although the utility model has been disclosed above with preferred embodiments, it is not intended to limit the utility model, and any person of ordinary skill in the art may make some changes without departing from the spirit and scope of the utility model. Movement and modification, so the protection scope of the present utility model is defined by the appended claims as the criterion. In addition, any embodiment or claim of the utility model does not need to achieve all the purposes or advantages or features disclosed in the utility model. In addition, the abstract part and the title are only used to assist the search of patent documents, and are not used to limit the scope of rights of the present utility model.

Claims (20)

1. A kind of optical engine is characterized in that comprising: first light valve; second light valve; third light valve; a first coherent light source adapted to provide a first color light beam with a first polarization direction; a second coherent light source adapted to provide a second color light beam with a second polarization direction; a third coherent light source adapted to provide a third color light beam; Split light system, including: The first polarization beam splitting unit, the first color light beam incident from the light source side of the first polarization beam splitting unit and having the first polarization direction will be reflected by the first polarization beam splitting unit, reflected by the first light valve and transmitted through the first polarization beam splitting unit in sequence. Through the first polarization beam splitting unit, the second color light beam incident from the light source side of the first polarization beam splitting unit and having the second polarization direction will sequentially pass through the first polarization beam splitting unit and be received by the second light valve. reflecting and being reflected by the first polarization splitting unit to merge with the first color light beam; a color separation unit configured on the optical path of the combined first color beam and the second color beam from the first polarization beam splitter; and The second polarization splitting unit is adapted to transmit the third color beam to the third light valve, and is adapted to transmit the third color beam reflected by the third light valve to the color separation unit, and the color separation unit It is suitable for combining the first, second and third color light beams into an image light beam. 2. The optical engine as claimed in claim 1, wherein the light splitting and combining system further comprises two prisms, which respectively bear against opposite sides of the first polarization splitting unit, one of the prisms is located on the first polarization splitting unit. A polarization beam splitting unit is on the light path between the first light valve, and another prism is located on the light path between the first polarization beam splitting unit and the second light valve, and the first polarization beam splitting unit is a polarization Spectral film. 3. The optical engine as claimed in claim 1, wherein the splitting and combining system further comprises two prisms, respectively supported on opposite sides of the color separation unit, one of the prisms is located at the first polarization splitter The second prism is located on the light path between the color separation unit and the second polarization light separation unit, and the color separation unit is a color separation film. 4. The optical engine as claimed in claim 1 , wherein the light splitting and combining system further comprises two prisms respectively supported on opposite sides of the second polarization splitting unit, one of the prisms is located at the splitting On the light path between the color unit and the second polarization beam splitting unit, and the second polarization beam splitting unit is a polarization beam splitting film. 5. The optical engine as claimed in claim 1 , wherein at least one of the first polarization splitting unit, the second polarization splitting unit and the color separation unit is plate-shaped. 6. The optical engine according to claim 1, wherein the first polarization direction is substantially perpendicular to the second polarization direction, and the polarization direction of the third light beam is the same as the first polarization direction or the second polarization direction . 7. A kind of optical engine is characterized in that comprising: first light valve; second light valve; third light valve; a first coherent light source adapted to provide a first color light beam with a first polarization direction; a second coherent light source adapted to provide a second color light beam having the first polarization direction; a third coherent light source adapted to provide a third color light beam with a second polarization direction; Split light system, including: a polarization beam splitting unit, the first color beam from the first coherent light source and the second color beam from the second coherent light source will emerge from the first surface of the polarization beam splitting unit after being delivered to the polarization beam splitting unit, The third color light beam from the third coherent light source will emerge from the second surface of the polarization beam splitting unit after being transmitted to the polarization beam splitting unit, wherein the third color light beam emitted from the second surface will be emitted by the polarization beam splitting unit. a third light valve reflects back to the second surface; and The color separation unit is arranged on the optical path of the first color light beam and the second color light beam from the first surface, wherein the first color light beam from the first surface will sequentially pass through the color separation unit and be The first light valve reflects, penetrates the color separation unit and returns to the first surface, and the second color light beam from the first surface will be reflected by the color separation unit, reflected by the second light valve, and returned to the first surface. the dichroic unit reflects and returns to the first surface, Wherein, the first, second and third color light beams returning to the polarization beam splitting unit from the first, second and third light valves are combined into an image beam by the polarization beam splitting unit. 8. The optical engine as claimed in claim 7, wherein the optical splitting and combining system further comprises a reflection unit configured on the light path of the third color light beam, and located between the polarization splitting unit and the third light valve time to reflect the third color light beam to the third light valve. 9. The optical engine as claimed in claim 8, wherein the light splitting and combining system further comprises a prism, which is supported on one side of the reflection unit and is located on the light path of the third color light beam, and the reflection unit for the reflective film. 10. The optical engine according to claim 8, wherein the reflection unit is plate-shaped. 11. The optical engine as claimed in claim 7, wherein the light splitting and combining system further comprises two prisms respectively supported on opposite sides of the polarization beam splitting unit, one of the prisms is located on the polarization beam splitting unit on the light path between the third light valve, and another prism is located on the light path between the polarization beam splitting unit and the color separation unit, and the polarization beam splitting unit is a polarization beam splitting film. 12. The optical engine as claimed in claim 7, wherein the light splitting and combining system further comprises two prisms respectively supported on opposite sides of the color separation unit, one of the prisms is located in the color separation unit on the light path between the first light valve, and another prism is located on the light path between the color separation unit and the second light valve, and the color separation unit is a color separation film. 13. The optical engine according to claim 7, wherein at least one of the polarization splitting unit and the color splitting unit is plate-shaped. 14. An optical engine, characterized in that comprising: first light valve; second light valve; third light valve; a first coherent light source adapted to provide a first color light beam with a first polarization direction; a second coherent light source adapted to provide a second color light beam with a second polarization direction; a third coherent light source adapted to provide a third color light beam; Split light system, including: The first color separation unit, after the first color light beam from the first coherent light source and the second color light beam from the second coherent light source are delivered to the first color separation unit, they will be transmitted from the first color separation unit and the third color light beam from the third coherent light source will emerge from the second surface of the first color separation unit after being delivered to the first color separation unit; The first polarization beam splitting unit, the first color light beam from the first color separation unit will be reflected by the first polarization beam splitting unit, reflected by the first light valve, and pass through the first polarization beam splitting unit, and from the first polarization beam splitting unit The second color light beam of the first color separation unit will sequentially pass through the first polarization beam splitting unit, be reflected by the second light valve, and be reflected by the first polarization beam splitting unit to merge with the first color beam; The second color separation unit is arranged on the optical path of the combined first color beam and the second color beam from the first polarization beam splitter; and The second polarization splitting unit is adapted to transmit the third color beam from the first dichroic unit to the third light valve, and is adapted to transmit the third color beam reflected by the third light valve to the The second color separation unit, wherein the second color separation unit is suitable for combining the first, second and third color light beams into an image light beam. 15. The optical engine as claimed in claim 14, wherein the light splitting and combining system further comprises two prisms respectively supported on opposite sides of the first dichroic unit, and one of the prisms is located on the first dichroic unit On the light path between the two polarization beam splitting units and the first color separation unit, and another prism is located on the light path between the first polarization beam splitting unit and the first color separation unit, and the first color separation unit For color separation film. 16. The optical engine as claimed in claim 14 , wherein the light splitting and combining system further comprises two prisms, which are respectively supported on opposite sides of the first polarization splitting unit, one of the prisms is located on the first polarizing beam splitting unit. On the optical path between a color separation unit and the first polarization beam splitting unit, and another prism is located on the optical path between the second color separation unit and the first polarization beam splitting unit, and the first polarization beam splitting unit For polarizing spectroscopic film. 17. The optical engine as claimed in claim 14 , wherein the light splitting and combining system further comprises two prisms respectively supported on opposite sides of the second dichroic unit, and one of the prisms is located on the second dichroic unit On the light path between a polarization beam splitting unit and the second color separation unit, and another prism is located on the light path between the second polarization beam splitting unit and the second color separation unit, and the second color separation unit For color separation film. 18. The optical engine as claimed in claim 14 , wherein the optical splitting and combining system further comprises two prisms respectively supported on opposite sides of the second polarization splitting unit, and one of the prisms is located on the second polarization splitting unit. On the light path between a color separation unit and the second polarization beam splitting unit, and another prism is located on the light path between the second color separation unit and the second polarization beam splitting unit, and the second polarization beam splitting unit For polarizing spectroscopic film. 19. The optical engine as claimed in claim 14 , wherein at least one of the first dichroic unit, the second dichroic unit, the first polarized beam-splitter unit, and the second polarized beam-splitter unit is plate-shaped. 20. The optical engine according to claim 14 , wherein the first polarization direction is substantially perpendicular to the second polarization direction, and the polarization direction of the third light beam is the same as the first polarization direction or the second polarization direction .

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