A compact DLP micro-projection optical engine

Abstract

The present invention provides a compact DLP micro-projection optical engine, including an illumination component, a focusing component and a projection lens, wherein the illumination component synthesizes a collimated light beam which is focused by the focusing component and projected by the projection lens for imaging, wherein the focusing component includes a light shaping device for obtaining high light energy utilization and uniform illumination of a large area, an integrally formed focusing lens, a total internal reflection element and a DMD light modulator, wherein the focusing lens includes a first mirror surface located on its light incident side and a second mirror surface located on its light exit side, wherein the first mirror surface and the second mirror surface are eccentrically arranged, the first mirror surface and the second mirror surface are tilted, and the focusing lens is tilted relative to the vertical line of the main optical axis of the light shaping device. The present invention further simplifies the projection optical machine, shortens the distance between the imaging optics and the illumination optics while ensuring sufficient projection effect, and further condenses the volume, making it more compact and easy to carry.

Description

Technical Field

[0001] The present invention relates to the field of projection optical engines, and in particular to a compact DLP micro-projection optical engine. Background Art

[0002] Digital Light Processing (DLP) is an imaging technology used in projectors and rear-projection televisions. DLP technology was first developed by Texas Instruments. It is still the main supplier of this technology. The Fraunhofer Institute of Dresden, Germany, also produces digital light processors for special purposes and calls them spatial light modulators (SLM). For example, Micronic Laser Systems of Sweden uses Fraunhofer's spatial light modulators to generate far-ultraviolet images in its Sigma plate silicon template imprinter. In DLP projectors, images are generated by DMDs (Digital Micromirror Devices). DMD devices are the basis of DLP. A DMD can be simply described as a semiconductor optical switch with 500,000 to 1.3 million micromirrors gathered on a CMOS silicon substrate. One micromirror represents one pixel, and the change rate is 1000 times / second, or faster. The size of each mirror is 14μm×14μm (or 16μm×16μm). To facilitate the adjustment of its direction and angle, a hinge-like rotating device is provided underneath. The rotation of the micro mirror is controlled by the digital drive signal from the CMOS RAM. When the digital signal is written into the SRAM, static electricity activates the address electrode, the mirror and the yoke plate (YOKE) to cause the hinge device to rotate. Once the corresponding signal is received, the mirror tilts 10° and tilts +12° with the digital signal from the SRAM; if the microscope is in a non-projection state, it is shown as "off" and tilted -12°. In short, the working principle of DMD is to reflect the required light with the help of the micro mirror device and absorb the unnecessary light through the light absorber to realize the projection of the image, and the direction of the light is realized by controlling the angle of the micro mirror with the help of electrostatic action. By addressing the storage unit under each mirror with a binary plane signal, each mirror on the DMD array is electrostatically tilted to the on or off state. The technology that determines how long each mirror tilts in which direction is called pulse width modulation (PWM). The mirrors can be switched on and off more than 1,000 times per second, at which point DLP becomes a simple optical system. After passing through a focusing lens and a color filter system, the light from the projection lamp is directed onto the DMD. When the mirrors are in the on position, they reflect light through the projection lens onto the screen to form a digital square pixel projected image. When the DMD base plate, projection lamp, color wheel and projection lens work together, these flip mirrors can work together to reflect the image onto a presentation wall, movie screen or TV screen.

[0003] With the continuous development of the information society, the market demand for portable projectors has become increasingly strong. There is room for further optimization of the size of existing DLP projectors, so the existing technology still needs to be improved and enhanced. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, an object of the present invention is to provide a compact DLP micro-projection optical engine.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] The present invention provides a compact DLP micro-projection optical engine, comprising an illumination component, a focusing component and a projection lens, wherein the illumination component synthesizes a collimated light beam, which is focused by the focusing component and projected by the projection lens for imaging, wherein the focusing component comprises a light shaping device for obtaining high light energy utilization and large-area uniform illumination, an integrally formed focusing lens, a total internal reflection element and a DMD light modulator, wherein the focusing lens comprises a first mirror surface located at its light incident side and a second mirror surface located at its light exit side, wherein the first mirror surface and the second mirror surface are eccentrically arranged, and the first mirror surface and the second mirror surface are tilted, wherein the focusing lens is tilted relative to a vertical line of a main optical axis of the light shaping device, wherein the collimated light beam passes through the light shaping device, is adjusted in sequence through the focusing lens and the total internal reflection element, and then is incident on the DMD light modulator, and then is converted by the DMD light modulator and is incident on the total internal reflection element, and the total internal reflection element reflects the collimated light beam to the projection lens for projection imaging.

[0007] Furthermore, in the compact DLP micro-projection optical engine, the first mirror surface and / or the second mirror surface is an even-order aspherical mirror surface.

[0008] Furthermore, in the compact DLP micro-projection optical engine, a first tilt angle is preset between the first mirror surface and the second mirror surface, and the first tilt angle is 1 to 25 degrees.

[0009] Furthermore, in the compact DLP micro-projection optical engine, an eccentric distance is preset between the first mirror surface and the second mirror surface, and the eccentric distance is 0.1 to 5 mm.

[0010] Furthermore, in the compact DLP micro-projection optical engine, the condenser lens is preset with a second tilt angle relative to a perpendicular line of the main optical axis of the light shaping device, and the second tilt angle is 1 to 45 degrees.

[0011] Specifically, in the compact DLP micro-projection optical engine, the light shaping device is a fly-eye lens or a light integrator rod.

[0012] Specifically, in the compact DLP micro-projection optical engine, the total internal reflection element is an RTIR combined prism.

[0013] In a preferred embodiment, the compact DLP micro-projection optical engine, the lighting assembly includes a three-primary color light source, a relay lens, a first filter and a second filter, the three-primary color light source includes a first collimated light source, a second collimated light source and a third collimated light source, the light beam of the first collimated light source and the light beam of the second collimated light source overlap at the light incident side of the relay lens via the first filter, and the light beam of the third collimated light source and the overlapping light beam passing through the relay lens overlap at the light incident side of the light shaping device via the second filter.

[0014] In a preferred embodiment, in the compact DLP micro-projection optical engine, the lighting assembly includes a three-primary color light source, a first filter and a second filter, the three-primary color light source includes a first collimated light source and a second collimated light source, the first collimated light source is a two-color light source, and the light beam of the first collimated light source overlaps with the light beam of the second collimated light source at the light incident side of the light shaping device via the first filter and the second filter.

[0015] In a preferred embodiment, in the compact DLP micro-projection optical engine, the lighting component includes a three-primary color light source, the three-primary color light source is a three-color light source or a white light source, and the light beams of the three-primary color light source are incident on the light incident side of the light shaping device.

[0016] Compared with the prior art, the present invention provides a compact DLP micro-projection optical engine, comprising an illumination component, a focusing component and a projection lens, wherein the illumination component synthesizes a collimated light beam, which is focused by the focusing component and projected by the projection lens for imaging, wherein the focusing component comprises a light shaping device for obtaining high light energy utilization and uniform illumination of a large area, an integrally formed focusing lens, a total internal reflection element and a DMD light modulator, wherein the focusing lens comprises a first mirror surface located on its light incident side and a second mirror surface located on its light exit side, wherein the first mirror surface and the second mirror surface are eccentrically arranged, and the first mirror surface and the second mirror surface are tilted, wherein the focusing lens is tilted relative to a vertical line of a main optical axis of the light shaping device, wherein the collimated light beam passes through the light shaping device, is adjusted in sequence through the focusing lens and the total internal reflection element, and then is incident on the DMD light modulator, and then converted by the DMD light modulator and is incident on the total internal reflection element, and the total internal reflection element reflects the collimated light beam to the projection lens for projection imaging. The present invention further simplifies the projection optical machine. While ensuring sufficient projection effect, some lenses in the prior art are removed, thus saving material costs. The number of parts that need to be assembled is reduced, which saves assembly costs, reduces assembly difficulty, and improves production efficiency. Since two lenses are removed, tolerance accumulation is reduced, which is beneficial to improving the product qualification rate, and shortens the distance between imaging optics and lighting optics, making the volume further concentrated, more compact, and easy to carry. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The present invention provides a schematic structural diagram of a preferred embodiment of the compact DLP micro-projection optical engine.

[0018] Figure 2 A schematic diagram of the top view structure of a condenser lens of a compact DLP micro-projection optical engine provided by the present invention.

[0019] Figure 3 A schematic diagram of the side structure of a condenser lens of a compact DLP micro-projection optical engine provided by the present invention.

[0020] Figure 4 A schematic diagram of the light path of a focusing assembly under a conventional optical framework provided by the present invention.

[0021] Figure 5 A schematic diagram of the light path of a light focusing component of a compact DLP micro-projection optical engine provided by the present invention.

[0022] Figure 6 The dot pattern on the DMD light modulator under the conventional optical framework provided by the present invention.

[0023] Figure 7 The dot pattern of the compact DLP micro-projection optical engine provided by the present invention on the DMD light modulator.

[0024] Figure 8 The light spot diagram on the DMD light modulator under the conventional optical framework provided by the present invention.

[0025] Fig. 9 This is a light spot diagram of the compact DLP micro-projection optical engine provided by the present invention on the DMD light modulator.

[0026] Fig.10 It is a structural schematic diagram of a further preferred embodiment of the compact DLP micro-projection optical engine provided by the present invention.

[0027] Fig.11 A schematic structural diagram of a further preferred embodiment provided by the present invention. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0029] It should be noted that when a component is referred to as being "mounted on", "fixed on" or "disposed on" another component, it may be directly on the other component or there may be a central component at the same time. When a component is referred to as being "connected to" another component, it may be directly connected to the other component or there may be a central component at the same time.

[0030] It should also be noted that the directional terms such as left, right, up, and down in the embodiments of the present invention are merely relative concepts or are based on the normal use status of the product and should not be considered as restrictive.

[0031] like Figure 1-Figure 3As shown, the present invention provides a compact DLP micro-projection optical engine, including an illumination component 10, a focusing component 20 and a projection lens 30. The illumination component 10 synthesizes a collimated light beam, which is focused by the focusing component 20 and projected by the projection lens 30 for imaging. The focusing component 20 includes a light shaping device 21 for obtaining high light energy utilization and uniform illumination of a large area, an integrally formed focusing lens 22, a total internal reflection element 23 and a DMD light modulator 24. The focusing lens 22 includes a first mirror surface located on its light incident side and a second mirror surface located on its light exit side. The second mirror on the optical side, the first mirror and the second mirror are eccentrically arranged, the first mirror and the second mirror are tilted, the condenser lens 22 is tilted relative to the vertical line of the main optical axis of the light shaping device 21, and the collimated light beam passes through the condenser lens 22 and the total internal reflection element 23 in sequence after passing through the light shaping device 21, and then is incident on the DMD light modulator 24, and after being converted by the DMD light modulator 24, it is incident on the total internal reflection element 23, and the total internal reflection element 23 reflects it to the projection lens 30 for projection imaging. Specifically, in the compact DLP micro-projection optical engine provided by the present invention, the light shaping device 21 is a fly-eye lens. Specifically, in the compact DLP micro-projection optical engine provided by the present invention, the total internal reflection element 23 is an RTIR combined prism.

[0032] Further, in the compact DLP micro-projection optical engine provided by the present invention, the first mirror and / or the second mirror are even-order aspheric mirrors. Of course, it can also be a spherical mirror, but the aspheric mirror has a better optical effect. Further, in the compact DLP micro-projection optical engine provided by the present invention, a first tilt angle ∠θ is preset between the first mirror and the second mirror, and the first tilt angle ∠θ is 1 to 25 degrees. Further, in the compact DLP micro-projection optical engine provided by the present invention, an eccentric distance is preset between the first mirror and the second mirror, and the eccentric distance is 0.1 to 5 mm. Further, in the compact DLP micro-projection optical engine provided by the present invention, the focusing lens 22 is preset with respect to the vertical line of the main optical axis of the light shaping device 21. The second tilt angle ∠A is 1 to 45 degrees. In this embodiment, the focusing lens 22 is arranged between the compound eye lens and the RTIR combined prism, and is arranged in the optical machine at a certain angle.

[0033] The present invention further simplifies the projection optical machine. While ensuring sufficient projection effect, some lenses in the prior art are removed, thus saving material costs. The number of parts that need to be assembled is reduced, which saves assembly costs, reduces assembly difficulty, and improves production efficiency. Since two lenses are removed, tolerance accumulation is reduced, which is beneficial to improving the product qualification rate, and shortens the distance between imaging optics and lighting optics, making the volume further concentrated, more compact, and easy to carry.

[0034] In a preferred embodiment of the present invention, the present invention provides a compact DLP micro-projection optical engine, wherein the lighting assembly 10 includes a three-primary color light source 11, a relay lens 100, a first filter 101, and a second filter 102. The three-primary color light source 11 includes a first collimated light source 111, a second collimated light source 112, and a third collimated light source 113. The light beams of the first collimated light source 111 and the second collimated light source 112 overlap at the light incident side of the relay lens 100 via the first filter 101, and the light beams of the third collimated light source 113 overlap at the light incident side of the light shaping device 21 via the second filter 102. The first collimated light source 111, the second collimated light source 112, and the third collimated light source 113 respectively use one of R, G, and B (red, green, and blue), and use LED lamp beads as light sources.

[0035] like Figure 4 The optical path schematic diagram of the focusing assembly under the conventional optical framework provided by the present invention and Figure 5 As shown in the optical path schematic diagram of the focusing component 20 of the compact DLP micro-projection optical engine provided by the present invention, compared with the conventional optical framework, the optical path of the light of the present invention in the focusing component 20 is significantly shorter, and the effect of the light of the present invention converging on the DMD light modulator 24 through the focusing component 20 is close to the effect of the light of the conventional framework converging on the DMD light modulator 24 through the focusing component 20.

[0036] like Figure 6 The dot pattern and Figure 7 As shown in the dot pattern of the compact DLP micro-projection optical engine provided by the present invention on the DMD light modulator 24, compared with the conventional optical architecture, the dot pattern of the present invention is closer to the conventional dot pattern, and the dot pattern of the present invention can be relatively regular and well cover the DMD light modulator 24.

[0037] like Figure 8 The light spot diagram and the light spot diagram on the DMD light modulator 24 under the conventional optical framework provided by the present invention Fig. 9 As shown in the light spot diagram of the compact DLP micro-projection optical engine provided by the present invention on the DMD light modulator 24, compared with the conventional optical architecture, the dot spot diagram of the present invention is basically similar to the conventional light spot diagram. The light spot diagram of the present invention can achieve uniform illumination and well cover the DMD light modulator 24.

[0038] like Fig.10As shown, in a further preferred embodiment of the present invention, the present invention provides a compact DLP micro-projection optical engine, the lighting assembly 10 includes a three-primary color light source 11, a first filter 101 and a second filter 102, the three-primary color light source 11 includes a first collimated light source 111 and a second collimated light source 112, the first collimated light source 111 is a two-color light source, that is, two lamp beads of R, G, B (red, green, blue) are packaged together, and the remaining one is used for the second collimated light source 112, the light beam of the first collimated light source 111 passes through the first filter 101 and the second filter 102 and overlaps with the light beam of the second collimated light source 112 at the light incident side of the light shaping device 21. The volume of the projection optical engine is further reduced.

[0039] like Fig.11 As shown, in a further preferred embodiment of the present invention, the compact DLP micro-projection optical engine provided by the present invention, the lighting assembly 10 includes a three-primary color light source 11, and the three-primary color light source 11 is a three-color light source or a white light source, that is, three lamp beads R, G, B (red, green, blue) are packaged together or a white light LED lamp bead is directly used, and the light beams of the three-primary color light source 11 are incident on the light incident side of the light shaping device 21. The volume of the projection optical engine is further reduced.

[0040] In summary, the present invention further simplifies the projection optical machine. Compared with the conventional optical framework, the optical path of the light of the present invention in the focusing assembly is significantly shorter, and the effect of the light of the present invention converging on the DMD light modulator through the focusing assembly is close to the effect of the light of the conventional framework converging on the DMD light modulator through the focusing assembly. Compared with the conventional optical framework, the dot pattern of the present invention is relatively close to the conventional dot pattern, and the dot pattern of the present invention can be relatively regular and well cover the DMD light modulator. Compared with the conventional optical framework, the dot pattern of the present invention is basically close to the conventional light pattern, and the light pattern of the present invention can achieve uniform illumination and well cover the DMD light modulator. While ensuring sufficient projection effect, the present invention removes some lenses in the prior art, saves material costs, reduces the number of parts to be assembled, saves assembly costs, reduces assembly difficulty, and improves production efficiency. Since two lenses are removed, tolerance accumulation is reduced, which is conducive to improving the qualified rate of products, and shortens the distance between imaging optics and lighting optics, so that the volume is further concentrated, more compact, and easy to carry.

[0041] It is understandable that those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of the present invention, and all these changes or substitutions should fall within the protection scope of the claims attached to the present invention.

Claims

1. A compact DLP micro-projection optical engine, comprising an illumination component, a focusing component and a projection lens, wherein the illumination component synthesizes a collimated light beam which is focused by the focusing component and projected by the projection lens for imaging. It is characterized in that The focusing assembly includes a light shaping device for obtaining high light energy utilization and large-area uniform illumination, an integrally formed focusing lens, a total internal reflection element and a DMD light modulator. The focusing lens includes a first mirror surface located on its light incident side and a second mirror surface located on its light exit side. The first mirror surface and the second mirror surface are eccentrically arranged, and the first mirror surface and the second mirror surface are tilted. The focusing lens is tilted relative to a vertical line of a main optical axis of the light shaping device. After passing through the light shaping device, the collimated light beam passes through the focusing lens and the total internal reflection element in sequence for adjustment and then is incident on the DMD light modulator. After being converted by the DMD light modulator, it is incident on the total internal reflection element. The total internal reflection element reflects the collimated light beam to a projection lens for projection imaging. The first mirror surface and / or the second mirror surface are even-order aspherical mirror surfaces. A first tilt angle is preset between the first mirror surface and the second mirror surface, and the first tilt angle is 1 to 25 degrees. The focusing lens is preset with respect to a vertical line of the main optical axis of the light shaping device. The second tilt angle is 1 to 45 degrees.

2. The compact DLP micro-projection optical engine according to claim 1, It is characterized in that An eccentric distance is preset between the first mirror surface and the second mirror surface, and the eccentric distance is 0.1-5 mm.

3. The compact DLP micro-projection optical engine according to claim 1, It is characterized in that The light shaping device is a fly-eye lens or a light integrator rod.

4. The compact DLP micro-projection optical engine according to claim 3, It is characterized in that The total internal reflection element is an RTIR combined prism.

5. The compact DLP micro-projection optical engine according to any one of claims 1 to 4, It is characterized in that The lighting assembly includes a three-primary color light source, a relay lens, a first filter and a second filter. The three-primary color light source includes a first collimated light source, a second collimated light source and a third collimated light source. The light beam of the first collimated light source and the light beam of the second collimated light source overlap on the light incident side of the relay lens via the first filter. The light beam of the third collimated light source and the overlapping light beam passing through the relay lens overlap on the light incident side of the light shaping device via the second filter.

6. The compact DLP micro-projection optical engine according to any one of claims 1 to 4, It is characterized in that The lighting assembly includes a three-primary color light source, a first filter and a second filter. The three-primary color light source includes a first collimated light source and a second collimated light source. The first collimated light source is a two-color light source. The light beam of the first collimated light source overlaps with the light beam of the second collimated light source at the light incident side of the light shaping device via the first filter and the second filter.

7. The compact DLP micro-projection optical engine according to any one of claims 1 to 4, It is characterized in that The lighting assembly includes a three-primary color light source, which is a three-color light source or a white light source, and the light beams of the three-primary color light source are incident on the light incident side of the light shaping device.

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