Lens for projector

Abstract

The invention discloses a lens for a projector, and relates to the field of lenses, the lens comprises an aluminum alloy frame, the bottom of the inner cavity of the aluminum alloy frame is provided with an optical substrate layer, the outer wall of the optical substrate layer is provided with a micro-groove, and the inner cavity of the micro-groove is internally provided with a shape memory alloy micro-spring array. The top of the optical substrate layer is provided with an infrared reflection metamaterial layer, and the top of the infrared reflection metamaterial layer is provided with an anti-reflection layer. According to the lens for the projector, by means of the lens composed of the optical substrate layer, the infrared reflection metamaterial layer, the anti-reflection layer and the shape memory alloy micro-spring array, the heat dissipation requirement during use of the lens can be guaranteed, heat generated by a high-power light source can be rapidly conducted out, and the lens has good optical stability and is suitable for being used for a projector. According to the invention, focal length drift and imaging blurring caused by thermal expansion can be avoided, light source bearing and heat conduction effects can be achieved through the optical substrate layer, and a directional heat conduction effect can be achieved in cooperation with the micro grooves.

Description

Technical Field

[0001] The present invention relates to the field of lenses, and in particular to a lens for a projector. Background Art

[0002] Optical lenses are essential components in machine vision systems, directly impacting image quality and the implementation and effectiveness of algorithms. Based on focal length, optical lenses can be categorized as short-focus, medium-focus, and long-focus; based on field of view, they can be classified as wide-angle, standard, and telephoto. Based on structure, they can be categorized as fixed-aperture, manual-aperture, automatic-aperture, varifocal, automatic-aperture, electric-varifocal, and electric-variable lenses. Industrial optical lenses are widely used for positioning and detecting highly reflective objects, such as metal, glass, film, and wafers.

[0003] Most lenses used in projectors use traditional heat dissipation solutions, such as fans and heat pipes, but they are prone to vibration, resulting in micro-displacement of optical components. At the same time, the disordered diffusion of heat flow will aggravate the temperature rise in the optical area, forming a vicious cycle of high brightness, high heat and high failure rate.

[0004] Therefore, it is necessary to propose a lens for a projector to solve the above problems. Summary of the Invention

[0005] The main purpose of the present invention is to provide a lens for a projector, which can effectively solve the problems in the background technology.

[0006] To achieve the above object, the technical solution adopted by the present invention is: A lens for a projector comprises an aluminum alloy frame, an optical base layer mounted at the bottom of an inner cavity of the aluminum alloy frame, microgrooves formed on an outer wall of the optical base layer, a shape memory alloy microspring array mounted in the inner cavity of the microgrooves, an infrared reflective metamaterial layer mounted on top of the optical base layer, and an anti-reflection layer mounted on top of the infrared reflective metamaterial layer.

[0007] Preferably, the wall of the aluminum alloy frame is installed with copper heat sink fins, a part of the copper heat sink fins extends to the outer wall of the aluminum alloy frame, and another part of the copper heat sink fins extends to the inner cavity of the aluminum alloy frame and fits in the inner cavity of the micro groove.

[0008] Preferably, the aluminum alloy frame is a vacuum cavity, the inner wall of the aluminum alloy frame and the edge of the optical base layer are sealed by anodic bonding, the optical base layer is borosilicate glass, the center of the optical base layer is the optical zone, and the remaining area of the optical base layer is the edge zone, a substrate electrode grid is installed in the optical zone, the substrate electrode grid is used to provide an electrical path and mechanical anchoring for the shape memory alloy microspring array, a heat dissipation guide electrode is installed in the edge zone, the heat dissipation guide electrode is connected to the copper heat dissipation fin, and the heat dissipation guide electrode is used to conduct heat from the micro groove to the copper heat dissipation fin.

[0009] Preferably, the microgrooves are evenly arranged along the circumference of the optical substrate layer, with a density of one hundred and twenty grooves per circle. The inner cavity of the microgrooves is filled with a filling layer, and the filling layer is reduced graphene oxide wrapped in boron nitride nanosheets. The microgrooves are a straight line with a fifteen-degree angle to the radial direction of the optical substrate layer.

[0010] Preferably, the infrared reflective metamaterial layer includes a metal-dielectric nano-harmonic array consisting of a titanium dioxide cylinder, a first silver ring and a second silver ring, the first silver ring is wrapped around the outer wall of the titanium dioxide cylinder, the titanium dioxide cylinder, the first silver ring and the second silver ring are all annular hollow structures, the second silver ring is wrapped around the outer wall of the first silver ring, the infrared reflective metamaterial layer is arranged in a hexagonal close-packed array, and the infrared reflective metamaterial layer completely covers the optical base layer.

[0011] Preferably, a nanoscale copper grid is installed in the hollow gap between the first silver ring and the second silver ring. The nanoscale copper grid is integrated with the first silver ring and the second silver ring and covers the titanium dioxide cylinder. The nanoscale copper grid is used to enhance infrared reflectivity and couple the localized surface plasmon resonance of the first silver ring and the second silver ring through grid resonance.

[0012] Preferably, the shape memory alloy microspring array is made of nickel-titanium alloy, and a copper column electrode is installed at the bottom of the shape memory alloy microspring array, and the copper column electrode is welded to the substrate electrode grid.

[0013] Preferably, the anti-reflection layer is a silica goose-eye nanocone array, the nanocones are hexagonal pyramids, the tips of the nanocones are facing the bottom, the silica goose-eye nanocone array is arranged in a gradient density, with sparse centers and dense edges, and the anti-reflection layer is directly grown on the surface of the infrared reflective metamaterial layer by a sol-gel method to form a continuous gradient refractive index layer.

[0014] Preferably, an upper copper electrode is installed on the top of the silica goose-eye nanocone array, and a lower copper electrode is installed on the bottom of the silica goose-eye nanocone array. The lower copper electrode is used to receive the thrust of the shape memory alloy microspring array and transmit it to the upper layer of the anti-reflection layer. The upper copper electrode is used to gradually change the refractive index in the visible light band.

[0015] Preferably, an electrode is installed on the top of the shape memory alloy microspring array. The electrode on the top of the shape memory alloy microspring array passes through the gap of the metal-dielectric nanoresonator array and is installed on the lower copper electrode. The electrode at the shape memory alloy microspring array is used to transmit mechanical thrust to drive the displacement of the anti-reflection layer.

[0016] Compared with the prior art, the present invention provides a lens for a projector, which has the following beneficial effects: The lens used in this projector is composed of an optical base layer, an infrared reflective metamaterial layer, an anti-reflection layer, and a shape memory alloy microspring array. It can ensure the heat dissipation requirements of the lens when in use, can quickly conduct heat generated by high-power light sources, and has good optical stability. It can avoid focal length drift and image blur caused by thermal expansion. The optical base layer is made of borosilicate glass, which can play the role of light source support and heat conduction, and can play the role of directional heat conduction in combination with micro-grooves.

[0017] The lens used in this projector is equipped with an infrared reflective metamaterial layer, which includes a titanium dioxide cylinder, a first silver ring and a second silver ring. This can ensure the infrared reflectivity and visible light penetration effect of the lens, and a gap is left between them to facilitate the connection between the shape memory alloy microspring array and the anti-reflection layer, which can achieve compatibility between optical functions and mechanical channels.

[0018] The lens used in this projector can contract when powered on through the shape memory alloy microspring array, thereby generating thrust, which can push the anti-reflection layer to move, converting thermal deformation into optical compensation power. Through the microgrooves set, its inclination angle can match the optical base layer, and its filling layer can form a heat flow waveguide channel to locate and guide the heat to the copper heat sink fins.

[0019] The lens used in this projector can reduce the visible light reflectivity by 0.5% through the gradual change of the refractive index through the anti-reflection layer. The lower copper electrode can receive the thrust of the shape memory alloy microspring array, and the upper copper electrode can realize optical modulation. The copper heat dissipation fins are coupled with the micro-grooves to quickly dissipate the heat inside the aluminum alloy frame.

[0020] The projector's lens utilizes an optical substrate, microgrooves, and an aluminum alloy frame to achieve a thermal management path during use. The optical substrate, shape memory alloy microspring array, and titanium dioxide cylinders form an optical compensation path, achieving physical decoupling and functional synergy in three-dimensional space, avoiding the interference between heat dissipation and optics seen in traditional solutions. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic structural diagram of the present invention as a whole; Figure 2 Schematic diagram of the structure of the optical substrate layer of the present invention; Figure 3 Schematic diagram of the structure of the infrared reflective metamaterial layer of the present invention; Figure 4 This invention Figure 2 Enlarged view of point A in the middle; Figure 5 Is a top view of the optical substrate layer of the present invention; Figure 6 This invention Figure 5 Enlarged view of point A in the middle.

[0022] In the figure: 1. Aluminum alloy frame; 2. Copper heat sink fins; 3. Anti-reflection layer; 4. Infrared reflective metamaterial layer; 5. Titanium dioxide cylinder; 6. First silver ring; 7. Second silver ring; 8. Optical base layer; 9. Optical zone; 10. Microgrooves; 11. Shape memory alloy microspring array; 12. Filling layer; 13. Substrate electrode grid; 14. Heat dissipation and diversion electrode. DETAILED DESCRIPTION

[0023] In order to make the technical means, creative features, objectives and effects achieved by the present invention easier to understand, the present invention is further described below in conjunction with specific implementation methods.

[0024] Example 1: like Figure 1 、 Figure 6As shown, a lens for a projector includes an aluminum alloy frame 1, an optical base layer 8 is installed at the bottom of the inner cavity of the aluminum alloy frame 1, a micro groove 10 is opened on the outer wall of the optical base layer 8, a shape memory alloy micro spring array 11 is installed in the inner cavity of the micro groove 10, an infrared reflective metamaterial layer 4 is installed on the top of the optical base layer 8, an anti-reflection layer 3 is installed on the top of the infrared reflective metamaterial layer 4, a copper heat sink 2 is installed on the wall of the aluminum alloy frame 1, a part of the copper heat sink fin 2 extends to the outer wall of the aluminum alloy frame 1, and the other part of the copper heat sink fin 2 extends to the inner cavity of the aluminum alloy frame 1 and fits in the inner cavity of the micro groove 10, the aluminum alloy frame 1 is a vacuum cavity, and the inner wall of the aluminum alloy frame 1 and the edge of the optical base layer 8 are connected by Anodic bonding sealing, the optical substrate layer 8 is borosilicate glass, the center of the optical substrate layer 8 is the optical zone 9, and the rest of the optical substrate layer 8 is the edge zone. A substrate electrode grid 13 is installed at the optical zone 9. The substrate electrode grid 13 is used to provide an electrical path and mechanical anchoring for the shape memory alloy microspring array 11. A heat dissipation guide electrode 14 is installed at the edge zone. The heat dissipation guide electrode 14 is connected to the copper heat dissipation fin 2. The heat dissipation guide electrode 14 is used to conduct heat from the micro groove 10 to the copper heat dissipation fin 2. The micro grooves 10 are evenly arranged along the circumference of the optical substrate layer 8 with a density of one hundred and twenty per circle. The inner cavity of the micro groove 10 is filled with a filling layer 12. The filling layer 12 is reduced graphene oxide wrapped with boron nitride nanosheets. The micro groove 1 0 is a straight line with a fifteen-degree angle between the radial direction of the optical base layer 8, the infrared reflective metamaterial layer 4 includes a metal-dielectric nano-harmonic array composed of a titanium dioxide cylinder 5, a first silver ring 6, and a second silver ring 7. The first silver ring 6 is wrapped around the outer wall of the titanium dioxide cylinder 5. The titanium dioxide cylinder 5, the first silver ring 6, and the second silver ring 7 are all annular hollow structures. The second silver ring 7 is wrapped around the outer wall of the first silver ring 6. The infrared reflective metamaterial layer 4 is arranged in a hexagonal close-packed array. The infrared reflective metamaterial layer 4 completely covers the optical base layer 8. A nano-scale copper grid is installed in the hollow gap between the first silver ring 6 and the second silver ring 7. The nano-scale copper grid is integrated with the first silver ring 6 and the second silver ring 7 and covers the titanium dioxide cylinder 5 at the same time. The meter-level copper grid is used to enhance infrared reflectivity. The localized surface plasmon resonance of the first silver ring 6 and the second silver ring 7 is coupled through grid resonance. The shape memory alloy microspring array 11 is a nickel-titanium alloy. A copper column electrode is installed at the bottom of the shape memory alloy microspring array 11. The copper column electrode is welded to the substrate electrode grid 13. The anti-reflection layer 3 is a silicon dioxide goose-eye nanocone array. The nanocones are hexagonal pyramids with the cone tips facing the bottom. The arrangement of the silicon dioxide goose-eye nanocone array is a gradient density, with sparse centers and dense edges. The anti-reflection layer 3 is directly grown on the surface of the infrared reflective metamaterial layer 4 by the sol-gel method to form a continuous gradient refractive index layer. The top of the silicon dioxide goose-eye nanocone array is installed with an upper copper electrode.A lower copper electrode is installed at the bottom of the silica goose-eye nanocone array. This lower copper electrode is used to receive the thrust from the shape memory alloy microspring array 11 and transmit it to the upper layer of the anti-reflection layer 3. An electrode is installed on the top of the shape memory alloy microspring array 11. The electrode on the top of the shape memory alloy microspring array 11 passes through the gap of the metal-dielectric nanocone array and is installed on the lower copper electrode. The electrode at the shape memory alloy microspring array 11 is used to transmit mechanical thrust, driving the displacement of the anti-reflection layer 3.

[0025] Example 2: A lens for a projector, wherein the thermal expansion coefficient of the optical base layer 8 is 3.3×10⁻ 6 / K, the shape memory alloy microspring array 11 is only installed in the edge area of the optical substrate layer 8; The reflectivity of the infrared reflective metamaterial layer 4 in the infrared band is: >92%@λ=800–2500nm; the transmittance of the infrared reflective metamaterial layer 4 in the visible light band is: >96%@λ=400–700nm; The gaps between the metal-dielectric nano-resonator arrays are filled with SiO2 glue with a dielectric strength of >10kV / mm to prevent high-voltage breakdown.

[0026] Example 3: A lens for a projector. The surface of a shape memory alloy microspring array 11 is sputtered with 200nm of Al2O3 to block the passage between the first silver ring 6 and the second silver ring 7 of the infrared reflective metamaterial layer 4. The shape memory alloy microspring array 11 has a pre-compression of 30% at room temperature. Its triggering mechanism is as follows: phase transition temperature: 45±2°C; deformation: maximum expansion rate: 4.2%; The upper copper electrode is used to gradually change the refractive index in the visible light band, that is, n=1.0→1.5. A mechanical limiter is also installed in the inner cavity of the aluminum alloy frame 1. The mechanical limiter is located at the lower copper electrode and is used to constrain the displacement of the anti-reflective layer 3 to avoid overload.

[0027] It should be noted that the present invention is a lens for a projector, and when in use, a high-power LED or laser light source generates heat when operating in the optical zone 9 of the optical base layer 8. After the temperature rises, the heat diffuses toward the edge through the lattice vibration of the borosilicate glass; After reaching the edge of the optical substrate layer 8, the heat enters the micro-grooves 10 with a 15° inclination angle. The micro-grooves 10 are filled with a filling layer 12. The inclination angle is designed to match the lattice orientation, reducing phonon scattering and improving heat flux density. The heat is conducted to the outer edge of the optical substrate layer 8 through the micro grooves 10 and dissipated to the ambient air through the copper heat sink fins 2; When the central area of the optical substrate layer 8 expands due to heat, radial displacement occurs, causing focal length drift. The displacement of the optical substrate layer 8 triggers the power supply of the shape memory alloy microspring array 11. The resistive heating causes it to contract. The shape memory alloy microspring array 11 passes through the gaps in the infrared reflective metamaterial layer 4 and is spot welded to the copper electrode on the lower layer of the anti-reflection layer 3 at the top, generating thrust. The copper electrode under the anti-reflection layer 3 receives the thrust, driving the anti-reflection layer 3 to produce axial displacement, accurately compensating for focal length drift. The displacement process of the anti-reflection layer 3 is constrained by a mechanical limiter to avoid squeezing the infrared reflective metamaterial layer 4.

[0028] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A lens for a projector, comprising an aluminum alloy frame (1), characterized in that: An optical base layer (8) is installed at the bottom of the inner cavity of the aluminum alloy frame (1), a micro groove (10) is provided on the outer wall of the optical base layer (8), a shape memory alloy micro spring array (11) is installed in the inner cavity of the micro groove (10), an infrared reflective metamaterial layer (4) is installed on the top of the optical base layer (8), and an anti-reflection layer (3) is installed on the top of the infrared reflective metamaterial layer (4).

2. The lens for a projector according to claim 1, wherein: Copper heat dissipation fins (2) are installed on the wall of the aluminum alloy frame (1), a portion of the copper heat dissipation fins (2) extends to the outer wall of the aluminum alloy frame (1), and another portion of the copper heat dissipation fins (2) extends to the inner cavity of the aluminum alloy frame (1) and fits into the inner cavity of the micro groove (10).

3. The lens for a projector according to claim 2, wherein: The aluminum alloy frame (1) is a vacuum cavity, and the inner wall of the aluminum alloy frame (1) and the edge of the optical substrate layer (8) are sealed by anodic bonding. The optical substrate layer (8) is borosilicate glass. The center of the optical substrate layer (8) is an optical zone (9), and the remaining area of the optical substrate layer (8) is an edge zone. A substrate electrode grid (13) is installed at the optical zone (9), and the substrate electrode grid (13) is used to provide an electrical path and mechanical anchoring for the shape memory alloy microspring array (11). A heat dissipation guide electrode (14) is installed at the edge zone, and the heat dissipation guide electrode (14) is connected to the copper heat dissipation fin (2). The heat dissipation guide electrode (14) is used to conduct heat from the micro groove (10) to the copper heat dissipation fin (2).

4. The lens for a projector according to claim 1, wherein: The microgrooves (10) are evenly arranged along the circumference of the optical substrate layer (8) at a density of one hundred and twenty per circle. The inner cavity of the microgrooves (10) is filled with a filling layer (12), and the filling layer (12) is reduced graphene oxide wrapped boron nitride nanosheets. The microgrooves (10) and the radial direction of the optical substrate layer (8) form a straight line with an angle of fifteen degrees.

5. The lens for a projector according to claim 1, wherein: The infrared reflective metamaterial layer (4) comprises a metal-dielectric nano-harmonic array consisting of a titanium dioxide cylinder (5), a first silver ring (6) and a second silver ring (7); the first silver ring (6) is wrapped around the outer wall of the titanium dioxide cylinder (5); the titanium dioxide cylinder (5), the first silver ring (6) and the second silver ring (7) are all annular hollow structures; the second silver ring (7) is wrapped around the outer wall of the first silver ring (6); the infrared reflective metamaterial layer (4) is arranged in a hexagonal close-packed array; and the infrared reflective metamaterial layer (4) completely covers the optical base layer (8).

6. The lens for a projector according to claim 5, characterized in that: A nanoscale copper grid is installed in the hollowed-out gap between the first silver ring (6) and the second silver ring (7). The nanoscale copper grid is integrated with the first silver ring (6) and the second silver ring (7) and covers the titanium dioxide cylinder (5). The nanoscale copper grid is used to enhance infrared reflectivity and couple the localized surface plasmon resonance of the first silver ring (6) and the second silver ring (7) through grid resonance.

7. The lens for a projector according to claim 1, wherein: The shape memory alloy microspring array (11) is a nickel-titanium alloy. A copper column electrode is installed at the bottom of the shape memory alloy microspring array (11), and the copper column electrode is welded to the substrate electrode grid (13).

8. The lens for a projector according to claim 7, wherein: The anti-reflection layer (3) is a silica goose-eye nanocone array, the nanocones are hexagonal pyramids, the tips of the nanocones are facing the bottom, and the arrangement of the silica goose-eye nanocone array is a gradient density, with sparse density at the center and dense density at the edge. The anti-reflection layer (3) is directly grown on the surface of the infrared reflective metamaterial layer (4) by a sol-gel method to form a continuous gradient refractive index layer.

9. The lens for a projector according to claim 8, characterized in that: An upper copper electrode is installed on the top of the silica goose-eye nanocone array, and a lower copper electrode is installed on the bottom of the silica goose-eye nanocone array. The lower copper electrode is used to receive the thrust of the shape memory alloy microspring array (11) and transmit it to the upper layer of the anti-reflection layer (3). The upper copper electrode is used to gradually change the refractive index in the visible light band.

10. The lens for a projector according to claim 9, characterized in that: An electrode is installed on the top of the shape memory alloy microspring array (11). The electrode on the top of the shape memory alloy microspring array (11) penetrates the gap of the metal-dielectric nano-harmonic array and is installed on the lower copper electrode. The electrode at the shape memory alloy microspring array (11) is used to transmit mechanical thrust to drive the anti-reflection layer (3) to move.

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