Projection device and area array scanner

Abstract

The projection device comprises a laser light source, a relay system, a polarized light splitting prism, a liquid crystal display and a lens, the laser light source can emit a polarized laser beam to the relay system, the relay system can zoom the polarized laser beam into a required size, and the polarized laser beam is reflected by the polarized light splitting prism and then is transmitted to the liquid crystal display. Vertical polarized light in the polarized laser beam is emitted into the liquid crystal display, the liquid crystal display can modulate the vertical polarized light and emit a polarized light beam corresponding to a projection picture towards the polarized light splitting prism, and finally projection imaging can be performed by the lens. In this way, the light emitting power of the light source of the projection device can be improved, the light emitting power can be improved, the projection picture of the projection device during working can be fine, obvious granular sensation does not exist, background noise can be improved, calculation of a follow-up algorithm is facilitated, and the effect of improving the calculation efficiency and precision of the algorithm is achieved.

Description

Technical Field

[0001] This utility model belongs to the technical field of projection optical path systems, and in particular relates to a projection device and a surface array scanner. Background Technology

[0002] Currently, existing projection devices mainly use LED light sources combined with DLP display technology. When this technology is applied to 3D scanning, the light output power is relatively low, and the projected image naturally has obvious graininess. This undoubtedly increases background noise and affects the efficiency and accuracy of 3D scanning. Utility Model Content

[0003] In view of this, it is necessary to provide a projection device and an area array scanner for solving the above-mentioned technical problems.

[0004] A projection device, comprising:

[0005] A laser source used to generate a polarized laser beam;

[0006] A relay system is used to scale the polarized laser beam;

[0007] A polarizing beam splitter is used to separate parallel polarized light and vertical polarized light in the polarized laser beam after it has been scaled up by the relay system. The polarizing beam splitter can transmit the parallel polarized light and can reflect the vertical polarized light.

[0008] A liquid crystal display is used to modulate the vertically polarized light reflected by the polarizing beam splitter to generate a polarized beam corresponding to the projected image, and the polarized beam can be emitted toward the polarizing beam splitter.

[0009] A lens for projecting the polarized light beam transmitted through the polarizing beam splitter.

[0010] It is understandable that using a polarized laser beam generated by a laser source as the light source and a liquid crystal display as the display imaging chip not only increases the luminous power of the projection device's light source and improves the output power, but also makes the projected image delicate and free of obvious graininess. This reduces background noise, which is beneficial for subsequent algorithm calculations and improves the efficiency and accuracy of algorithm calculations.

[0011] In one embodiment, the laser source is configured as a vertical cavity surface-emitting laser.

[0012] It is understandable that by utilizing the small-angle emission characteristics of a vertical cavity surface-emitting laser, this projection device can eliminate the need for a collimation system that compresses the emission angle of a polarized laser beam, and can directly use a conical light bar to homogenize the polarized laser beam.

[0013] In one embodiment, the projection device further includes a polarizer disposed between the polarizing beam splitter and the liquid crystal display.

[0014] It is understandable that by utilizing the structural characteristics of polarizers, the polarization of the laser beam directed by the liquid crystal display towards the polarizing beam splitter can be improved, thus making the projected image brighter in bright states and darker in dark states when the projection device is working.

[0015] In one embodiment, the projection device further includes a beam homogenization system disposed between the laser source and the relay system, for shaping the polarized laser beam generated by the laser source and guiding the shaped polarized laser beam into the relay system.

[0016] It is understandable that a homogenizing system is used to shape the polarized laser beam, thereby achieving the purpose of homogenizing the polarized laser beam.

[0017] In one embodiment, the light homogenizing system further includes a conical hollow light rod, the inner wall of which is coated with a reflective film.

[0018] In one embodiment, the relay system includes a lens assembly, which includes a focusing lens.

[0019] In one embodiment, the lens assembly includes at least two focusing lenses, which are arranged sequentially along the optical path of the polarized laser beam.

[0020] In one embodiment, the lens assembly further includes a reflector disposed in the optical path of the polarized laser beam between two adjacent focusing lenses.

[0021] Understandably, this relay system can use a reflector to reflect the polarized laser beam between two adjacent focusing lenses, which reduces the assembly space required when installing two adjacent focusing lenses, thereby reducing the overall size of the relay system.

[0022] In one embodiment, the polarizing beam splitter includes a polarizing beam splitter film and two triangular prisms. The polarizing beam splitter film is disposed at the adhesive position between the two triangular prisms, and the two triangular prisms are connected by adhesive bonding.

[0023] The polarizing beam splitter can transmit the parallel polarized light and reflect the vertical polarized light.

[0024] This application also provides an area array scanner, including the projection device described above.

[0025] Due to the application of the above technical solution, this utility model has the following advantages compared with the prior art:

[0026] The projection device and area array scanner claimed in this application use a polarized laser beam generated by a laser source as the light source and a liquid crystal display as the display imaging chip. This not only improves the light emission power of the light source of the projection device and increases the light output power, but also makes the projected image of the projection device delicate and free of obvious graininess when it is working. This can improve background noise, so as to facilitate the calculation of subsequent algorithms and improve the efficiency and accuracy of algorithm calculation. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the projection device provided in this application.

[0029] Figure 2 This is a schematic diagram of the optical path of the polarizing beam splitter, liquid crystal display and lens working together to project an image in this application.

[0030] Figure 3 This is a schematic diagram of the structure of the polarized laser beam in this application when it is transmitted between two adjacent focusing lenses and a mirror.

[0031] Reference numerals: 100, projection device; 10, laser source; 20, conical hollow light bar; 21, reflective film; 30, relay system; 31, focusing lens; 32, mirror; 40, polarizing beam splitter; 41, polarizing beam splitter film; 42, triangular prism; 50, liquid crystal display; 60, lens; 101, parallel polarized light; 102, vertically polarized light; 103, polarized beam. Detailed Implementation

[0032] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] It should be noted that when a component is said to be "located on" another component, it can be directly located on the other component or may have an intervening component. When a component is considered to be "located on" another component, it can be directly located on the other component or may have an intervening component. When a component is considered to be "fixed to" another component, it can be directly fixed to the other component or may have an intervening component.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0035] like Figure 1 As shown, the projection device 100 provided in this application includes a laser source 10, a relay system 30, a polarizing beam splitter 40, a liquid crystal display 50, and a lens 60. The laser source 10 is used to generate a polarized laser beam; the relay system 30 is used to scale the polarized laser beam; the polarizing beam splitter 40 is used to separate parallel polarized light 101 and vertical polarized light 102 in the polarized laser beam scaled by the relay system 30, wherein the polarizing beam splitter 40 can transmit parallel polarized light 101 and reflect vertical polarized light 102; the liquid crystal display 50 is used to modulate the vertical polarized light 102 reflected by the polarizing beam splitter 40 to generate a polarized beam 103 corresponding to the projected image, and the polarized beam 103 can be emitted toward the polarizing beam splitter 40; the lens 60 is used to project the polarized beam 103 transmitted by the polarizing beam splitter 40.

[0036] It is understandable that the polarized laser beam generated by the laser light source 10 serves as the light source, and the liquid crystal display 50 serves as the display imaging chip. This not only improves the light emission power of the light source of the projection device 100 and increases the light output power, but also makes the projected image of the projection device 100 delicate and free of obvious graininess when it is working. This can improve the background noise, which is conducive to the calculation of subsequent algorithms and has the effect of improving the calculation efficiency and accuracy of the algorithm.

[0037] In one embodiment, the laser source 10 is configured as a vertical cavity surface emitter (VCSEL). By utilizing the structural characteristics of the VCSEL, the emission power of the polarized laser beam can reach hundreds of watts, and the emission angle of the polarized laser beam is relatively small, generally around 20°. This allows the projection device 100 to eliminate the need for a collimation system that compresses the emission angle of the polarized laser beam, and a conical light bar can be used directly to homogenize the polarized laser beam.

[0038] In one embodiment, the projection device 100 further includes a beam homogenization system disposed between the laser source 10 and the relay system 30. This system is used to shape the polarized laser beam generated by the laser source 10 and guide the shaped polarized laser beam into the relay system 30. This allows the projection device 100 to use the beam homogenization system to shape the polarized laser beam, thus achieving beam homogenization of the polarized laser beam.

[0039] like Figure 1 As shown, the homogenizing system includes a conical hollow light rod 20, with a reflective film 21 coated on its inner wall. The reflective film 21 can reflect polarized laser beams. In other words, the conical hollow light rod 20 in this embodiment can utilize the reflective film 21 to reflect the polarized laser beam multiple times, achieving the purpose of homogenizing the polarized laser beam. It should be noted that the polarized laser beam is reflected multiple times within the conical hollow light rod 20, and each reflection forms a virtual light source. Multiple reflections form a two-dimensional virtual light source matrix, thereby making the polarized laser beam emitted through the conical hollow light rod 20 more uniform. It is understood that in other embodiments, a solid light rod or compound eyes can also be used to shape the polarized laser beam generated by the laser source 10, which will not be elaborated upon here.

[0040] It should be noted that, in this embodiment, the size of the incident end of the conical hollow light rod 20 is mainly determined by the light emission size and emission angle of the light source, the size of the exit end of the conical hollow light rod 20 is determined by the effective area of ​​the liquid crystal display 50 and the aperture coefficient of the vertically polarized light 102 incident on the liquid crystal display 50, and the length of the conical hollow light rod 20 is determined by the light intensity uniformity required by the application scenario. It is generally believed that the polarized laser beam is reflected three times in the conical hollow light rod 20 until the uniformity of the polarized laser beam emitted through the conical hollow light rod 20 meets the requirements.

[0041] like Figure 3As shown, in one embodiment, the relay system 30 includes a lens assembly (not shown), which includes a focusing lens 31. That is, the relay system 30 uses the focusing lens 31 to scale the polarized laser beam. Here, the lens assembly includes at least two focusing lenses 31, which are arranged sequentially along the optical path of the polarized laser beam. The focusing lenses are configured as spherical lenses and / or aspherical lenses, specifically using four commercially available plano-convex lenses, which reduces costs.

[0042] like Figure 3 As shown, in one embodiment, the lens assembly further includes a reflector 32, which is disposed in the optical path of the polarized laser beam between two adjacent focusing lenses 31. This allows the relay system 30 to reflect the polarized laser beam between the two adjacent focusing lenses 31 using the reflector 32, thereby reducing the assembly space required when installing the two adjacent focusing lenses 31 and thus reducing the overall size of the relay system 30.

[0043] like Figure 2 As shown, in one embodiment, the polarizing beam splitter 40 includes a polarizing beam splitter 41, which is arranged at an angle relative to the liquid crystal display 50. The polarizing beam splitter 41 can transmit parallel polarized light 101 and reflect vertically polarized light 102. Specifically, the polarizing beam splitter 40 uses the polarizing beam splitter 41 to reflect vertically polarized light 102 and transmit parallel polarized light 101 and polarized beam 103. Here, the tilt angle of the polarizing beam splitter 41 is 45°, so that the polarized laser beam scaled by the relay system 30 enters the polarizing beam splitter 41 at a 45° tilt angle, and correspondingly, the vertically polarized light 102 reflected by the liquid crystal display 50 also enters the polarizing beam splitter 41 at a 45° tilt angle.

[0044] like Figure 2 As shown, in this embodiment, the polarizing beam splitter 40 further includes two triangular prisms 42, which are connected by adhesive bonding. The polarizing beam splitter 41 is disposed at the adhesive bonding position between the two triangular prisms 42, and the polarizing beam splitter 41 can be attached to one of the triangular prisms 42 by coating.

[0045] like Figure 2As shown, in one embodiment, the liquid crystal display 50 includes liquid crystal layer pixels, which can modulate vertically polarized light 102 to change the polarization direction of the vertically polarized light 102 after passing through the liquid crystal layer pixels; wherein, the external voltage of the liquid crystal layer pixels can be adjusted. That is, the liquid crystal display 50 can change the polarization of vertically polarized light, thus meeting the usage requirements of the liquid crystal display 50 to modulate vertically polarized light 102 and generate a polarized beam 103.

[0046] It should be noted that when the external voltage of the liquid crystal display 50 is zero, the polarization direction of the incident vertically polarized light 102 does not change after passing through the liquid crystal layer pixels. When the vertically polarized light 102 reaches the bottom of the liquid crystal display 50, it is reflected back and then reflected again by the polarizing beam splitter 40. The polarized beam 103 returns along the same path and is not projected through the lens 60, resulting in zero output and a "dark state". However, when the external voltage of the liquid crystal layer pixels is not zero, the polarization direction of the incident vertically polarized light 102 changes after passing through the liquid crystal layer pixels. After reaching the bottom of the liquid crystal display 50, it is reflected back, allowing the polarized beam 103 to be directly transmitted through the polarizing beam splitter 40, resulting in a "bright state", which can then be projected onto an image by the lens 60.

[0047] In one embodiment, the projection device 100 further includes a polarizer (not shown), which is positioned between the polarizing beam splitter 40 and the liquid crystal display 50. The polarizer adjusts the polarization of the polarized beam 103 projected from the liquid crystal display 50 onto the polarizing beam splitter 40. By utilizing the structural characteristics of the polarizer, the polarization of the polarized beam 103 projected onto the liquid crystal display 50 and then onto the polarizing beam splitter 40 can be improved. This results in a brighter bright state and a darker dark state for the polarized beam projected by the lens 60 when the projection device 100 is operating.

[0048] In summary, when the projection device 100 of this application is working, the laser source 10 emits a polarized laser beam towards the conical hollow light bar 20. The polarized laser beam, after being shaped by the conical hollow light bar 20, is guided into the relay system 30. Then, the relay system 30 can scale the polarized laser beam to the required size and reflect it through the polarizing beam splitter 40, so that the vertically polarized light 102 is projected into the liquid crystal display 50. The liquid crystal display 50 can modulate the vertically polarized light 102 and emit a polarized beam 103 corresponding to the projected image towards the polarizing beam splitter 40. Finally, the image can be projected through the lens 60.

[0049] In addition, this application also provides an area array scanner, including the projection device 100 described above.

[0050] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0051] Those skilled in the art should recognize that the above embodiments are only used to illustrate the present utility model and are not intended to limit the present utility model. Any appropriate changes and variations made to the above embodiments within the scope of the present utility model shall fall within the scope of protection claimed by the present utility model.

Claims

1. A projection device, characterized in that, The projection device (100) includes: A laser source (10) is used to generate a polarized laser beam; A relay system (30) is used to scale the polarized laser beam; A polarizing beam splitter (40) is used to separate parallel polarized light (101) and vertical polarized light (102) in the polarized laser beam after being scaled by the relay system (30), wherein the polarizing beam splitter (40) can transmit the parallel polarized light (101) and the polarizing beam splitter (40) can reflect the vertical polarized light (102). The liquid crystal display (50) is used to modulate the vertically polarized light (102) reflected by the polarizing beam splitter (40) to generate a polarized beam (103) corresponding to the projected image, and the polarized beam (103) can be emitted toward the polarizing beam splitter (40). The lens (60) is used to project the polarized beam (103) transmitted through the polarizing beam splitter (40).

2. The projection device according to claim 1, characterized in that, The laser source (10) is configured as a vertical cavity surface-emitting laser.

3. The projection device according to claim 1, characterized in that, The projection device (100) also includes a polarizer, which is positioned between the polarizing beam splitter (40) and the liquid crystal display (50).

4. The projection device according to claim 1, characterized in that, The projection device (100) further includes a beam homogenization system, which is disposed between the laser source (10) and the relay system (30) for shaping the polarized laser beam generated by the laser source (10) and guiding the shaped polarized laser beam into the relay system (30).

5. The projection device according to claim 4, characterized in that, The light homogenizing system includes a conical hollow light rod (20), the inner wall of which is coated with a reflective film (21).

6. The projection device according to claim 1, characterized in that, The relay system (30) includes a lens assembly, which includes a focusing lens (31).

7. The projection device according to claim 6, characterized in that, The lens assembly includes at least two focusing lenses (31), which are arranged sequentially along the optical path of the polarized laser beam.

8. The projection device according to claim 7, characterized in that, The lens assembly also includes a reflector (32) disposed on the optical path of the polarized laser beam between two adjacent focusing lenses (31).

9. The projection device according to claim 1, characterized in that, The polarizing beam splitter (40) includes a polarizing beam splitter film (41) and two triangular prisms (42). The polarizing beam splitter film (41) is disposed at the adhesive position between the two triangular prisms (42), and the two triangular prisms (42) are connected by adhesive bonding. The polarizing beam splitter (41) can transmit the parallel polarized light (101), and the polarizing beam splitter (41) can reflect the vertical polarized light (102).

10. A surface scan scanner, characterized in that, The projection device (100) includes any one of claims 1 to 9.

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