Illumination system and projection device
By using the first light concentrator, a light spectrometer, a phase converter, a first reflector and a dimmer in the lighting system, the light beam emitted by the light source is converted into a polarized light with a consistent direction and the same polarization state, which solves the problems of low light utilization and high manufacturing cost of the light concentrator in the traditional LCD projection device, and achieves efficient light utilization and the effect of reducing manufacturing costs.
Patent Information
- Application Number
- CN202421385542.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-18
- Publication Date
- 2025-04-01
- Estimated Expiration
- 2034-06-18
AI Technical Summary
The light source of the traditional LCD projection device emits non-polarized light, resulting in a large loss of brightness after the light passes through the light modulator and a low light utilization rate. Large-size light modulators require large-size condenser lenses, which increases manufacturing cost and difficulty.
An illumination system is designed to convert the light beam emitted by the light source into multiple polarized light with consistent directions and same polarization state through the first light concentrator, light spectrometer, phase converter, first reflector and dimming member. The output beam width is greater than the beam width emitted by the light source, and adapts to a larger-sized dimming member.
It greatly improves the efficiency of light entering the dimmer, improves the light utilization rate, reduces the manufacturing cost and difficulty of the light concentrator, and at the same time simplifies the optical path design.
Smart Images
Figure CN222704880U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of optics, in particular to an illumination system and a projection device comprising the same. Background Art
[0002] At present, LCD projection can be divided into single LCD and 3LCD according to the number of LCD panels. Single LCD projector occupies the lowest end of the market with its low price, good quality, maturity and stability. It is a form of existence that cannot be replaced by other micro-display technologies in the same price range.
[0003] In terms of brightness, traditional LCD projection has shortcomings. Corresponding to the LCD projector, the spatial light modulator is a liquid crystal screen. The light source of the traditional LCD projection device emits non-polarized light, and the non-polarized light is directly incident on the light modulator in the projection device. Since the liquid crystal light valve needs to process polarized light, the non-polarized light will lose a lot of brightness after passing through the light modulator, and the light utilization rate is low, which in turn affects the brightness of the projection picture.
[0004] In addition, since the light modulator receives parallel light, the illumination system of the LCD projection device also needs to be equipped with a lens assembly for collimating and focusing the non-polarized light. The light modulator has different size specifications according to the requirements of the projector product structure, performance and cost. In the conventional technology, for a larger-sized light modulator, the lens assembly for collimating and focusing the non-polarized light also needs to be synchronously set to a large size, which will lead to an increase in the manufacturing cost and difficulty of the focusing lens.
[0005] Therefore, it is necessary to design a new type of lighting system and projection device to improve the above defects. Utility Model Content
[0006] The purpose of the utility model is to provide an illumination system and a projection device, which can convert a light beam emitted by a light source into multiple polarized lights with the same direction and the same polarization state, so as to greatly improve the efficiency of entering the dimming element, and at the same time make the width of the light beam output by the illumination system larger than the width of the light beam emitted by the light source, thereby improving the light utilization rate and realizing that a smaller focusing element can be adapted to a larger dimming element, effectively reducing the manufacturing cost and difficulty of the focusing element.
[0007] In order to achieve the above-mentioned purpose, the utility model provides a lighting system and a projection device. The lighting system comprises:
[0008] light source;
[0009] A first focusing element, arranged relative to the light source, for collimating and focusing the light beam emitted by the light source;
[0010] A beam splitter, arranged relative to the first light focusing element, for splitting the light beam passing through the first light focusing element into a transmission light beam and a reflection light beam with different polarization states;
[0011] A phase conversion element is disposed in the optical path of one of the transmitted light beam and the reflected light beam, and is used to convert the polarization state of the transmitted light beam or the reflected light beam so that the polarization state of the reflected light beam is the same as that of the transmitted light beam;
[0012] A first reflector is disposed in the optical path of the reflected light beam and is used to change the propagation direction of the reflected light beam so that the propagation direction of the reflected light beam is consistent with that of the transmitted light beam; and
[0013] A light modulator, disposed on the outgoing light path of the phase conversion element and the first reflection element, for modulating the transmitted light beam and the reflected light beam having the same polarization state and propagation direction, and outputting a modulated light beam;
[0014] The width of the modulated light beam is greater than the width of the light beam emitted by the light source, and the size of the light modulator is greater than the size of the first light focusing element.
[0015] Preferably, the width of the modulated light beam is twice the width of the light beam emitted by the light source; and the size of the light modulator is twice the size of the first focusing element.
[0016] Preferably, the beam splitter is a polarization beam splitter; the polarization beam splitter reflects the reflected light beam, and the transmitted light beam penetrates the polarization beam splitter.
[0017] Preferably, the first reflective element is disposed opposite to the beam splitter and is located in the optical path of the reflected light beam to change the propagation direction of the reflected light beam.
[0018] Preferably, the phase conversion element is a half-wave plate.
[0019] Preferably, the dimming element is a spatial light modulator.
[0020] Preferably, a projection device comprises:
[0021] the lighting system; and,
[0022] The lens and the light source are respectively located at opposite sides of the light modulator, and the lens is used to receive the modulated light beam for optical projection.
[0023] Preferably, the projection device further comprises: a second reflector, disposed between the light modulating element and the lens, for reflecting the modulated light beam to the lens.
[0024] Preferably, the projection device further comprises: a second light focusing element, disposed between the first light focusing element and the light splitting element; and,
[0025] The third focusing element is arranged between the light modulating element and the lens, and is used for focusing the modulated light beam.
[0026] Preferably, a projection device comprises:
[0027] The lighting system has a plurality of;
[0028] a light combining module, arranged on the output light paths of the plurality of lighting systems, for combining the modulated light beams output by the plurality of lighting systems to generate a synthesized light; and
[0029] The lens is arranged on the outgoing light path of the light combining module and is used for projecting the combined light onto a preset projection plane to form a projection image.
[0030] Compared with the prior art, the lighting system provided by the utility model includes a light source, a first focusing element, a beam splitter, a phase conversion element, a first reflector and a dimming element. The first focusing element collimates and focuses the light beam emitted by the light source and then inputs it into the beam splitter. The beam splitter divides the light beam passing through the first focusing element into a transmitted light beam and a reflected light beam with different polarization states; by means of a phase conversion element arranged in the optical path of the transmitted light beam or the reflected light beam, and a first reflector arranged in the optical path of the reflected light beam, the transmitted light beam and the reflected light beam have the same polarization state and the same propagation direction, and the transmitted light beam and the reflected light beam with the same propagation direction and polarization state both enter the dimming element, so that the light beam width output by the lighting system is greater than the light beam width emitted by the light source. While improving the light utilization rate, a smaller focusing element can be adapted to a larger dimming element, the optical path design is simple, and the manufacturing cost of the focusing element is effectively reduced. BRIEF DESCRIPTION OF THE DRAWINGS
[0031] Figure 1 It is a structural schematic diagram of a lighting system according to an embodiment of the utility model;
[0032] Figure 2 This is a schematic diagram of the structure of a projection device according to an embodiment of the utility model;
[0033] Figure 3 This is a schematic diagram of the structure of a projection device according to an embodiment of the utility model;
[0034] Figure 4 It is a structural schematic diagram of a projection device according to an embodiment of the utility model. DETAILED DESCRIPTION
[0035] In order to provide a further understanding of the purpose, structure, features, and functions of the present invention, the present invention is described in detail below with reference to the embodiments.
[0036] Certain words are used in the specification and claims to refer to specific components. Those with ordinary knowledge in the field should understand that manufacturers may use different terms to refer to the same component. This specification and claims do not use differences in names as a way to distinguish components, but rather use differences in components' functions as the criteria for distinction. The term "including" mentioned throughout the specification and claims is an open-ended term and should be interpreted as "including but not limited to".
[0037] Please refer to Figure 1 , Figure 1 A structural schematic diagram of an illumination system 10 according to an embodiment of the present invention is disclosed, wherein the illumination system can be applied to a projection device to provide a projection beam.
[0038] like Figure 1 As shown, the lighting system 10 includes a light source 1, a first light focusing element 2, a light splitting element 3, a phase conversion element 5, a first reflector 4 and a dimming element 6. The light source 1 emits a non-polarized light beam. The first light focusing element 2 is arranged relative to the light source 1 and is used to collimate and focus the light beam emitted by the light source 1. The light splitting element 3 is arranged relative to the first light focusing element 2 and is used to split the light beam passing through the first light focusing element 2 into a transmission light beam and a reflection light beam with different polarization states, wherein the transmission light beam passes through the light splitting element 3 and the reflection light beam is reflected by the light splitting element 3. Figure 1 As shown, the phase conversion element 5 is arranged in the path of the reflected light beam to convert the polarization state of the reflected light beam to be the same as the polarization state of the transmitted light beam; in another embodiment, the phase conversion element 5 can also be arranged in the light path of the projected light beam as needed, and the utility model is not limited to this. Further, the first reflector 4 is arranged in the light path of the reflected light beam to change the propagation direction of the reflected light beam so that the propagation direction of the reflected light beam is the same as that of the transmitted light beam. The dimming element 6 is arranged on the output light path of the phase conversion element 5 and the first reflector 4 to modulate the transmitted light beam and the reflected light beam having the same polarization state and consistent propagation direction, and output a modulated light beam.
[0039] It can be seen that the lighting system 10 proposed in the present invention can convert the light beam emitted by the light source 1 into multiple polarized lights with the same direction and the same polarization state, thereby greatly improving the efficiency of entering the dimming element 6, and the width of the modulated light beam output by the lighting system 10 is greater than the width of the light beam emitted by the light source 1, so that the smaller first focusing element 2 can be adapted to the larger dimming element 6; it can effectively reduce the manufacturing cost and difficulty of the first focusing element 2, improve the light utilization rate, and the optical path design is simple.
[0040] In one embodiment, the first light focusing element 2 is a Fresnel lens, which can collimate and focus the light beam emitted by the light source 1; the light modulating element 6 is a spatial light modulator. The width of the modulated light beam is twice the width of the light beam emitted by the light source 1, and the diameter of the first light focusing element 2 is half the diameter of the light modulating element 6, so that the Fresnel lens (i.e., the first light focusing element 2) is small in size and easy to manufacture.
[0041] In one embodiment, the beam splitter 3 is a polarization beam splitter, which splits the light beam passing through the first light focusing element 2 into a transmitted light beam having a first polarization state and a reflected light beam having a second polarization state, wherein the first polarization state is, for example, one of a P polarization state and an S polarization state, and the second polarization state is, for example, the other of the P polarization state and the S polarization state. The P polarization state and the S polarization state are linear polarizations, and the transmitted light beam having the first polarization state T1 and the reflected light beam having the second polarization state T2 have propagation directions that differ by 90 degrees, for example.
[0042] In one of the embodiments, the phase conversion element 5 is a half-wave plate, and the first reflector 4 is parallel to the polarization beam splitter and is arranged in the light path of the reflected light beam to change the propagation direction of all reflected light beams so that the direction of the reflected light beam is consistent with that of the transmitted light beam. By adjusting the distance between the first reflector 4 and the polarization beam splitter, the size of the reflected light beam and the transmitted light beam entering the dimming element 6 can be further adjusted, and the lighting system 10 has a compact structure and is suitable for projectors of various specifications.
[0043] Please refer to Figure 2 , which discloses a schematic diagram of the structure of a projection device 100 according to an embodiment of the present invention. The projection device 100 includes an illumination system 20 and a projection lens 30. Figure 1 The lighting system 10 further comprises a second light focusing element 7, a third light focusing element 8 and a polarizing element 9. Figure 2 As shown, the second light focusing element 7 is disposed between the first light focusing element 2 and the light splitting element 3, and is preferably a Fresnel lens, so as to further collimate and focus the light output by the first light focusing element 2. The third light focusing element 8 is disposed between the light modulating element 6 and the lens 30, and is preferably a Fresnel lens, so as to further collimate and focus the modulated light beam output by the light modulating element 6. By disposing the second light focusing element 7 and the third light focusing element 8, the optical path can be further shortened, the volume of the projection device can be reduced, and the illumination system 20 can be suitable for a small projector.
[0044] The lens 30 is used to receive the modulated light beam after focusing for optical projection. The polarizer 9 is disposed between the third focusing element 8 and the lens 30 to further control the direction and transmittance of the modulated light beam after focusing, so that the image projected by the lens 30 onto the preset projection plane has higher definition.
[0045] Please refer to Figure 3 , which discloses a structural diagram of a projection device 200 according to another embodiment of the present invention. Figure 2 The projection device 200 further includes a second reflector 40, which is disposed between the third focusing element 8 and the lens 30 to reflect the modulated light beam after focusing to the lens 30. In this way, the position between the lens 30 and the lighting system 20 is more flexible.
[0046] Please refer to Figure 4 , which discloses a structural schematic diagram of a projection device 300 according to another embodiment of the utility model. Among them, the projection device 300 includes an illumination system 10 (in actual design, or according to demand, the illumination system 10 is replaced with the above-mentioned illumination system 20), a light combining module and a lens 30. The above-mentioned illumination system 10 has multiple, preferably three, light sources 1 of the three illumination systems 10 respectively emit a red light beam, a green light beam and a blue light beam. The above-mentioned light combining module is preferably a light combining prism, which is arranged on the output light path of the multiple illumination systems 10 to combine the modulated light beams output by the multiple illumination systems 10 into a beam of synthesized light. The above-mentioned lens 30 is arranged on the output light path of the light combining module to project the synthesized light onto a preset projection plane to display a projection image.
[0047] To sum up, the lighting system provided by the utility model can convert the light beam emitted by the light source 1 into multiple polarized lights with the same direction and the same polarization state, so as to improve the efficiency of entering the dimming element 6 and reduce light loss; at the same time, the width of the light beam output by the lighting system is greater than the width of the light beam emitted by the light source 1, so that a smaller focusing element can be adapted to a larger light modulator, the optical path design is simple, and the manufacturing cost and difficulty of the focusing element are effectively reduced.
[0048] The present invention has been described by the above-mentioned relevant embodiments, however, the above-mentioned embodiments are only examples for implementing the present invention. It must be pointed out that the disclosed embodiments do not limit the scope of the present invention. On the contrary, any changes and modifications made without departing from the spirit and scope of the present invention are within the scope of patent protection of the present invention.
Claims
1. A lighting system, characterized in that: Include: light source; A first focusing element, arranged relative to the light source, for collimating and focusing the light beam emitted by the light source; A beam splitter, arranged relative to the first light focusing element, for splitting the light beam passing through the first light focusing element into a transmission light beam and a reflection light beam with different polarization states; A phase conversion element, disposed in the optical path of one of the transmitted light beam and the reflected light beam, for converting the polarization state of the transmitted light beam or the reflected light beam so that the polarization state of the reflected light beam is the same as that of the transmitted light beam; A first reflector is disposed in the optical path of the reflected light beam and is used to change the propagation direction of the reflected light beam so that the propagation direction of the reflected light beam is consistent with that of the transmitted light beam; and A light modulator, disposed on the outgoing light path of the phase conversion element and the first reflection element, for modulating the transmitted light beam and the reflected light beam having the same polarization state and propagation direction, and outputting a modulated light beam; The width of the modulated light beam is greater than the width of the light beam emitted by the light source, and the size of the light modulator is greater than the size of the first light focusing element.
2. The lighting system according to claim 1, characterized in that The width of the modulated light beam is twice the width of the light beam emitted by the light source; the size of the light modulator is twice the size of the first light focusing element.
3. The lighting system according to claim 1, characterized in that The beam splitter is a polarization beam splitter; the polarization beam splitter reflects the reflected light beam, and the transmitted light beam penetrates the polarization beam splitter.
4. The lighting system according to claim 3, characterized in that The first reflecting element is arranged opposite to the light splitting element and is located in the light path of the reflected light beam to change the propagation direction of the reflected light beam.
5. The lighting system according to claim 1, characterized in that The phase conversion element is a half wave plate.
6. The lighting system according to claim 1, characterized in that The light modulating element is a spatial light modulator.
7. A projection device, characterized in that: include: The lighting system according to any one of claims 1 to 6; and, The lens and the light source are respectively located at opposite sides of the light modulator, and the lens is used to receive the modulated light beam for optical projection.
8. The projection device according to claim 7, characterized in that: Also includes: The second reflecting element is arranged between the light modulating element and the lens, and is used for reflecting the modulated light beam to the lens.
9. The projection device according to claim 7, characterized in that: Also includes: A second light concentrating element, disposed between the first light concentrating element and the light splitting element; and, The third focusing element is arranged between the light modulating element and the lens, and is used for focusing the modulated light beam.
10. A projection device, characterized in that: include: The lighting system according to any one of claims 1 to 6, wherein the lighting system has a plurality of; A light combining module, arranged on the output light paths of the plurality of lighting systems, for combining the modulated light beams output by the plurality of lighting systems to generate a synthetic light; as well as, The lens is arranged on the outgoing light path of the light combining module and is used for projecting the combined light onto a preset projection plane to form a projection image.