Dynamic multi-spot projection optical system based on LED light source

Abstract

This invention discloses a dynamic multi-spot projection optical system based on an LED light source, comprising an LED light source, a reflector, a grating sheet, a condenser lens, a concave mirror, and an optical reflection assembly. The LED light source is located at the bottom of the reflector, and the grating sheet has a light-transmitting area with a preset pattern shape. The reflector is composed of several planar mirrors A, and the concave mirror is composed of several planar mirrors B. The light emitted by the LED light source is formed into a patterned beam by the grating sheet, and the conical reflector divides and reflects the beam into multiple sub-beams, which are then guided to the condenser lens by the optical reflection assembly. This invention, using a low-cost, laser-free, and safe LED solution, achieves complex dynamic light and shadow effects comparable to or even surpassing laser projection through innovative optical design, while maintaining consistent image clarity within a projection distance range of 2-15 meters.

Description

Technical Field

[0001] This utility model relates to the field of LED projection technology, and in particular to a dynamic multi-spot projection optical system based on an LED light source. Background Technology

[0002] Dynamic multi-spot projection devices are widely used to create special lighting and shadow effects. Existing technologies include systems that use laser light sources in conjunction with diffractive optical elements (DOEs) to achieve multi-spot projection. However, these solutions suffer from high laser costs, eye safety risks, and speckle noise issues caused by laser coherence, making it difficult to achieve sharp-edged, irregular pattern projections.

[0003] In addition, another approach uses an LED array to achieve multi-spot projection, with multiple LED chips forming images separately. However, this approach requires complex circuit control and heat dissipation design, resulting in high system costs and difficulty in achieving dynamic rotation of the light spots.

[0004] While LEDs, as incoherent light sources, offer advantages such as low cost and high safety, their Lambertian emission characteristics result in large light divergence angles. Existing solutions, such as those in CN201820987654.3, employ conventional spherical lens groups for beam shaping, which struggles to simultaneously correct spherical aberration, astigmatism, and field curvature caused by large-angle light, leading to blurred edges on the projected light spot and poor overall uniformity.

[0005] Therefore, there is an urgent need in this field for a new type of optical system that can overcome the problems of strong divergence and severe aberrations of LED light sources, and realize high-density, high-definition dynamic multi-spot projection. Utility Model Content

[0006] The technical problem to be solved by this utility model embodiment is to provide a dynamic multi-spot projection optical system based on LED light source, which can project complex non-circular patterns at low cost, high efficiency and high definition, and achieve dynamic rotation effect, while solving the problems of low light collection efficiency and serious aberration caused by LED Lambertian light emission.

[0007] To address the aforementioned technical problems, this utility model proposes a dynamic multi-spot projection optical system based on an LED light source, comprising an LED light source, a reflector, a grating sheet, a condenser lens, a concave mirror, and an optical reflection component. The LED light source is located at the bottom of the reflector, and the grating sheet is correspondingly located above the LED light source, with a light-transmitting area of ​​a preset pattern shape on the grating sheet. The reflector is composed of several planar mirrors A, which are sequentially connected to form a conical reflective surface. The concave mirror is composed of several planar mirrors B. The optical reflection component reflects the light reflected from the reflector to the condenser lens, which then focuses the light before reflecting it out by the concave mirror.

[0008] Furthermore, it also includes a grating turntable, with several grating plates arranged around the center of the turntable. The grating plates above the LED light source are switched by rotating the grating turntable.

[0009] Furthermore, the optical reflection assembly consists of a plane mirror A and a plane mirror B. The plane mirror A is positioned above the reflector, and the plane mirror B is positioned in front of the plane mirror A. The plane mirror A reflects the light reflected from the reflector to the plane mirror B, and then the plane mirror B reflects the light to the condenser lens.

[0010] Furthermore, a light-blocking plate is provided between the condenser lens and the reflector.

[0011] Furthermore, the condenser lens adopts a biconvex aspherical structure, where both its front and rear surfaces are even-order aspherical surfaces, and satisfy the following conditions: The focal length is 162.99mm±5%, the radius of curvature of the front surface is 26180mm±5%, the radius of curvature of the rear surface is 80.214mm±5%, the conicity of the front surface is k=37.527±5%, the conicity of the rear surface is k=-0.9545±5%, and the center thickness is 5.1325mm±5%.

[0012] Furthermore, the refractive index of the condenser lens is 1.493±5%, and the Abbe number is 57.2±5%.

[0013] Furthermore, the preset pattern shape is one or more of the following: maple leaf shape, snowflake shape, star shape, cloud shape, and swastika shape.

[0014] Furthermore, it also includes a rotary drive module, with a concave reflector correspondingly mounted on the output shaft of the rotary drive module.

[0015] Furthermore, the concave mirror is a parabolic mirror.

[0016] Furthermore, the reflector includes n planar mirrors A, and the concave mirror includes m planar mirrors B. The n+1 light spots of a preset pattern shape reflected by the optical reflection component are used as a projection unit. The dynamic multi-spot projection optical system based on LED light source satisfies the following equation: 0.6× δ < (X×360° / m) < δ ; Where X represents the angular magnification of the entire optical system of the dynamic multi-spot projection optical system based on LED light source. δ The angular diameter of a single projection unit on the projection plane.

[0017] The beneficial effects of this utility model are as follows: 1. Safety and cost advantages: This utility model uses ordinary LED light source, avoiding expensive lasers and strict safety certifications, reducing costs by more than 50% and making the application safer.

[0018] 2. Functional and performance advantages: (1) This utility model achieves clear projection of complex patterns (such as snowflakes and maple leaves) and overcomes the problem of laser speckle; (2) This utility model uses a biconvex aspherical condensing lens to effectively correct aberrations and ensure clear light spot edges; (3) The optical system of this utility model has a great depth of field, and the clarity remains unchanged when the projection distance varies from 2 to 15 meters. It also has extremely high installation flexibility.

[0019] 3. Technological Originality: This utility model organically combines a "multi-plane mirror beam splitting system" with a "customized aspherical lens aberration correction system," and for the first time successfully applies LED light sources to dynamic multi-spot projection of high-density complex patterns, achieving a direct replacement and functional superiority over laser solutions.

[0020] 4. Commercial value: This utility model lowers the manufacturing threshold and cost, laying the foundation for the popularization of complex light and shadow effects in smart homes, ambient lighting, commercial displays and other fields. Attached Figure Description

[0021] Figure 1 This is a three-dimensional structural diagram of the dynamic multi-spot projection optical system based on LED light source according to an embodiment of the present invention.

[0022] Figure 2 This is a three-dimensional structural diagram of the dynamic multi-spot projection optical system based on an LED light source, according to another embodiment of this utility model.

[0023] Figure 3 This is a three-dimensional structural diagram of the reflector according to an embodiment of the present invention.

[0024] Figure 4 This is a three-dimensional structural diagram of the grating turntable according to an embodiment of the present invention.

[0025] Figure 5 This is a three-dimensional structural diagram of the LED light source according to an embodiment of the present invention.

[0026] Figure 6 This is an aberration curve of the condenser lens of this utility model at wavelengths of 486nm, 587nm and 656nm.

[0027] Figure 7 This is a comparison chart of the modulation transfer function (MTF) curves of the optical system of this utility model at projection distances of 2 meters, 8 meters, and 15 meters.

[0028] Explanation of icon numbers 1. Reflector, 2. Grating plate, 3. Condensing lens, 4. Concave mirror, 5. Rotary drive module, 6. Base, 7. Plane mirror A, 8. Plane mirror B, 9. Plane mirror A, 10. Plane mirror B, 11. Rotating shaft, 12. Light blocking plate, 13. LED light source, 14. Grating turntable, 15. Substrate, 16. LED. Detailed Implementation

[0029] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of this application can be combined with each other. The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] In this embodiment of the invention, directional indicators (such as up, down, left, right, front, back, etc.) are only used to explain the relative positional relationship and movement of the components in a specific posture (as shown in the attached figure). If the specific posture changes, the directional indicators will also change accordingly.

[0031] Furthermore, in this utility model, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features.

[0032] Please refer to Figures 1-5 The dynamic multi-spot projection optical system based on LED light source according to this utility model embodiment includes an LED light source, a reflector, a grating sheet, a condenser lens, a concave reflector, an optical reflection component, a rotation drive module, and a base.

[0033] The LED light source, reflector, focusing lens, concave mirror, optical reflection components, and rotation drive module are mounted on the base. The LED light source is located at the bottom of the reflector and is used to emit incoherent light.

[0034] The grating sheet is positioned above and close to the LED light source. The grating sheet has a pre-defined pattern of light-transmitting areas (not circular). Light emitted from the LED light source passes through these light-transmitting areas, forming a light spot with the pre-defined pattern. The LED light source is a single-point LED light source.

[0035] The reflector consists of several planar mirrors A, which are sequentially connected to form a conical reflective surface used to reflect and split a light beam passing through the light-transmitting area into multiple sub-beams. The reflector includes n planar mirrors A. The reflector reflects n light spots of a predetermined pattern shape to an optical reflection component (i.e., planar mirrors A). The optical reflection component reflects the n light spots of the predetermined pattern shape reflected by the reflector, as well as a light spot of a predetermined pattern shape passing through a grating plate, for a total of n+1 light spots of the predetermined pattern shape. The light spot of the predetermined pattern shape passing through the grating plate is distributed in the middle of the ring of the n light spots of the predetermined pattern shape reflected by the reflector, and the n+1 light spots form a projection unit. The taper (i.e., tilt angle) of the planar mirrors A affects the distance between the outer n light spots and the central light spot of the projection unit.

[0036] The optical reflection assembly reflects the light from the reflector to a condenser lens, where it is focused and then reflected again by a concave mirror. The optical reflection assembly includes at least two planar mirrors to change the direction of the light path, thereby shortening the total optical path of the system. The condenser lens is used to image the multiple sub-beams.

[0037] A concave reflector consists of several plane reflectors B. The concave reflector reflects the imaged light beam onto the projection surface, forming multiple light spots of a preset pattern shape. The concave reflector includes m plane reflectors B. The projection units are reflected onto the projection surface by the m plane reflectors B, forming m projection units, i.e., a total of m × (n+1) light spots of a preset pattern shape. The concave reflector is a parabolic reflector. The curvature of the concave reflector affects the spacing between the m projection units.

[0038] A concave reflector is mounted on the output shaft of the rotary drive module. The rotary drive module can be a DC geared motor. The rotary drive module drives the concave reflector, causing the projected pattern on the projection surface to move, creating an atmosphere of flowing starlight.

[0039] The condenser lens is made of optical-grade PMMA or polycarbonate. It employs a biconvex aspherical structure, with both its front and rear surfaces (in the direction of light transmission) being even-order aspherical surfaces. The z-function of the condenser lens surface satisfies: ; Where c is the curvature, the reciprocal of the radius; r is the radial coordinate; and k is the conic coefficient. For even-order aspherical coefficients, corresponding to The order of , where i is a positive integer.

[0040] The parameters of the condenser lens meet the following requirements: The focal length is 162.99mm±5%, the radius of curvature of the front surface is 26180mm±5%, the radius of curvature of the rear surface is 80.214mm±5%, the conicity of the front surface is k=37.527±5%, the conicity of the rear surface is k=-0.9545±5%, and the center thickness is 5.1325mm±5%.

[0041] The LED light source has a wavelength range of 486nm-656nm, the condenser lens has a refractive index of 1.493±5%, and an Abbe number of 57.2±5%. Simulation verification of this invention shows a maximum spherical aberration of <0.1mm and field curvature of <0.5% within the 486nm-656nm wavelength range. Due to manufacturing tolerances of optical components and the tolerance distribution of the optical system, the optical system of this invention can still maintain its excellent aberration correction function and depth-of-field characteristics when the above parameters vary within ±5%. This invention resolves the contradiction between large-angle LED emission and clear imaging with multiple light spots through a specific combination of parameters; this is the core difference between this invention and conventional designs.

[0042] The optical system of this invention has a modulation transfer function greater than 0.4 at a spatial frequency of 20 lp / mm within a projection distance range of 2-15 meters, and the total length of the optical system is less than 200 mm.

[0043] This invention achieves the following technical effects through a specific optical design of a biconvex aspherical focusing lens and its combination with a conical beam-splitting structure: 1. Superior aberration correction capability: The optimized combination of aspherical coefficient and radius of curvature in this invention effectively corrects spherical aberration and astigmatism caused by the large divergence angle of the LED light source and the beam splitting of the conical reflector, ensuring that the edges of each of the hundreds of patterned light spots on the projection surface remain sharp. The measured Strehl ratio of the projected light spot is greater than 0.8, far superior to conventional spherical lens systems (typically less than 0.6).

[0044] 2. "Depth of field extension" effect: The lens design of this utility model enables the optical system to have a very large depth of field. When the projection distance varies within the range of 2-15 meters, the image sharpness remains unchanged (MTF value changes by less than 10%), and only the image size changes proportionally, significantly improving installation flexibility. This characteristic is achieved through a specific combination of aspherical coefficients, which can maintain stable image quality over a wide range.

[0045] 3. System compatibility: The lens focal length and optical path design of this utility model are matched to ensure that the overall system length is compact (less than 200mm) and can be used with a concave mirror to accurately project the image plane to the expected distance.

[0046] This invention can utilize a single grating sheet, which can be directly integrated into the LED light source (i.e., the top of the LED, replacing the original lens on the top of the LED). The LED light source consists of a substrate and an LED, with the substrate being an aluminum nitride ceramic substrate or a copper substrate. Alternatively, multiple grating sheets can be used, integrated onto a grating turntable, with several grating sheets arranged around the center of the turntable. The shapes of the light-transmitting areas on the grating sheets on the turntable are different. Rotating the turntable switches the grating sheets above the LED light source, thereby changing the projected pattern. In practice, the turntable can be mounted on a base via a rotating shaft. The turntable can be manually or electrically controlled. For manual control, a rotating handle can be connected to the bottom of the shaft; for electric control, a micro motor can be directly connected to the shaft to drive the pattern switching.

[0047] In one implementation, the optical reflection assembly consists of a plane mirror A and a plane mirror B. Plane mirror A is positioned directly above the reflector, and plane mirror B is positioned in front of plane mirror A. Plane mirror A reflects the light reflected from the reflector to plane mirror B, which then reflects it to the condenser lens. The optical reflection assembly consists of two plane mirrors, simplifying the overall optical system of this LED-based dynamic multi-spot projection optical system.

[0048] In one implementation, a light-blocking plate is provided between the condenser lens and the reflector. The light-blocking plate prevents light leakage, blocks stray light from diffuse reflection, and prevents stray light from interfering with the projected pattern.

[0049] In one implementation, the LED chip is a monochromatic or multicolor light source, so that the projected pattern is monochromatic or multicolor.

[0050] In one implementation, the preset pattern shape is one or more of the following: maple leaf, snowflake, star, cloud, and swastika. For example, when the preset pattern shape is maple leaf, the LED chip can use a yellow / orange-red light source, which is projected onto the projection surface (generally a ceiling or wall) through the optical path system of this invention. Then, the rotation drive module drives the pattern movement, creating an atmosphere of falling maple leaves. For example, when the preset pattern shape is snowflake, the LED chip can use a white light source, which is projected onto the projection surface through the optical path system of this invention. Then, the rotation drive module drives the pattern movement, creating an atmosphere of falling snowflakes. For example, when the preset pattern shape is star, the LED chip can use a white light source, which is projected onto the projection surface through the optical path system of this invention. The system projects onto a projection surface, and then a rotation drive module drives the pattern to move, creating an atmosphere of flowing starlight, a dazzling galaxy, and scattered stars. For example, when the preset pattern shape is cloud-shaped, the LED chip can use a white light source, which is projected onto the projection surface through the optical path system of this invention, and then the rotation drive module drives the pattern to move, creating an atmosphere of surging clouds. For example, when the preset pattern shape is swastika-shaped, the LED chip can use a gold light source, which is projected onto the projection surface through the optical path system of this invention, and then the rotation drive module drives the pattern to move, creating an atmosphere of Buddha's light shining everywhere, which is especially suitable for use in temples.

[0051] As one implementation method, a dynamic multi-spot projection optical system based on an LED light source satisfies the following equation: 0.6× δ < (X×360° / m) < δ ; Where X represents the angular magnification of the entire optical system of the dynamic multi-spot projection optical system based on LED light source. δ δ is the angular diameter of a single projection unit on the projection surface (i.e., the angular diameter subtended by a cluster of light spots formed by adjacent sub-beams on the projection surface, calculated as: δ = 2 × arctan(d / 2D), where d is the physical size of the light spot cluster and D is the projection distance). The angular magnification of the optical system is related to the focal length of the condenser lens, the curvature of the concave mirror, the image distance, and the taper of the reflector. The angular magnification X ranges from 0.1 to 0.3, m ranges from 20 to 40, and δ ranges from 1.5° to 3.0°. This invention allows some projection units to partially intersect, resulting in a more visually natural projection effect.

[0052] In this invention, the light emitted from the LED light source is formed into a patterned beam by a grating sheet. A conical reflector splits and reflects the beam into multiple sub-beams, which are then guided by an optical mirror assembly to a condenser lens. The biconvex aspherical condenser lens of this invention, through a specific optical design, effectively corrects system aberrations, ensuring clear imaging of all sub-beams. Finally, a concave reflector reflects the imaging beam onto the target surface, forming multiple uniform and clear dynamic patterned light spots. This invention, using a low-cost, laser-free, and safe LED solution, achieves complex dynamic light and shadow effects comparable to or even surpassing laser projection through innovative optical design, while maintaining consistent image clarity within a projection distance range of 2-15 meters. Example 1

[0053] The LED light source uses a white LED chip with a rated power of 6W and a color temperature of 6500K to emit incoherent light, fundamentally avoiding the problem of laser speckle.

[0054] The grating sheet is made of stainless steel sheet through photolithography. It is 0.1mm thick and 0.2mm apart from the LED light source chip. The light-transmitting area with snowflake pattern is etched on it, and the light-transmitting hole size is 1.8mm×1.8mm.

[0055] The reflector consists of eight planar reflectors (A) joined together to form a conical structure with a 45° cone angle. The mirrors are vacuum-plated with aluminum, achieving a reflectivity greater than 95%. This reflector is used to divide and reflect the patterned beam emitted by the LED light source into eight identical sub-beams. The optical reflection assembly comprises a first planar reflector and a second planar reflector, each with a surface size of 36mm × 36mm and a silver-plated finish. This assembly is used to redirect the optical path twice, reducing the total optical path length of the system from 350mm to 200mm.

[0056] The condenser lens is manufactured using optical-grade PMMA material through injection molding. Its optical parameters are as follows: focal length 162.99mm, front surface radius of curvature 26180mm, rear surface radius of curvature 80.214mm, front surface conicity k=37.527, rear surface conicity k=-0.9545, and center thickness 5.1325mm.

[0057] Aberration test data: like Figure 6 As shown in the simulation results using LightTools optical software, this lens exhibits excellent aberration performance at different wavelengths: 486nm wavelength: maximum spherical aberration 0.09mm, field curvature 0.4% 587nm wavelength: maximum spherical aberration 0.08mm, field curvature 0.3%. 656nm wavelength: maximum spherical aberration 0.10mm, field curvature 0.45% Aberrations at all wavelengths meet the requirements for clear imaging of multiple light spots.

[0058] Supplementary wavelength test data: 450nm wavelength: maximum spherical aberration 0.11mm, field curvature 0.48% 520nm wavelength: maximum spherical aberration 0.085mm, field curvature 0.35% 620nm wavelength: maximum spherical aberration 0.095mm, field curvature 0.41% Test results show that the lens maintains excellent aberration correction performance across the entire visible light spectrum from 450 to 656 nm.

[0059] The concave reflector is composed of 36 flat reflectors B spliced ​​together to form a concave structure. Each flat reflector is 5mm×5mm in size and its installation angle is precisely calculated to reflect the imaged light beam to the final projection surface.

[0060] The rotary drive module uses a 28BYJ-48 stepper motor with a speed of 1rpm-5rpm to drive the concave reflector to rotate, so that all the pattern light spots on the projection surface produce a dynamic effect of flowing and rotating.

[0061] The light emitted by the LED light source forms a patterned beam after passing through a grating sheet, and is then split into eight sub-beams by a reflector. These sub-beams are redirected by an optical reflection component and then incident on a biconvex aspherical focusing lens, which clearly images all the sub-beams. Finally, the imaged beam is reflected by a rotating concave mirror onto the target wall, forming 288 (8×36) uniform, clear, and dynamic snowflake pattern light spots.

[0062] In this embodiment, m=36 and angular magnification X=0.18. At a projection distance of 3 meters, δ=2.5°. Substituting these values, we get (0.18 × 360° / 36) = 1.8°, which satisfies 0.6 × 2.5° = 1.5° < 1.8° < 2.5°.

[0063] This invention ensures that adjacent projection units projected by adjacent plane mirrors B on the concave reflector have a partial overlap on the projection surface. When (X × 360° / m) is too greater than δ, the light spot spacing is too large and the distribution is sparse; when (X × 360° / m) is too less than δ, the light spots overlap severely and the pattern is blurred. This invention determines this ratio range through extensive experiments and optical simulations, enabling the light spots to visually form a continuous, uniform, and seamless "sky-wide" effect.

[0064] like Figure 7 As shown in the figure, the MTF performance of the optical system of this embodiment at different projection distances, based on actual testing, is as follows: 2-meter projection distance: MTF = 0.48 at 20 lp / mm; 8-meter projection distance: MTF = 0.45 at 20 lp / mm; 15-meter projection distance: MTF = 0.42 at 20 lp / mm.

[0065] The MTF value was greater than 0.4 at all test distances, meeting the requirements for clear imaging, and the variation was less than 10%, proving that the system has stable imaging performance in the range of 2-15 meters.

[0066] The projection distance test data is as follows: At a projection distance of 4 meters: MTF = 0.47 at 20 lp / mm; At a projection distance of 6 meters: MTF = 0.46 at 20 lp / mm; At a projection distance of 10 meters and a speed of 20 lp / mm, the MTF is 0.44. 12-meter projection distance: MTF = 0.43 at 20 lp / mm.

[0067] Test results show that the optical system of this embodiment maintains excellent imaging performance across a range of 2-15 meters. Example 2

[0068] Example 2 is basically the same as Example 1, except that: the grating sheet has a maple leaf-shaped light-transmitting area; the reflector is composed of 12 plane mirrors; and the concave reflector is composed of 24 plane mirrors. The optical system parameters of this embodiment are adjusted to satisfy the relationship 0.6δ < (X × 360° / m) < δ, where X = 0.15, m = 24, and δ = 2.2° (at a projection distance of 3 meters). The calculated value is (X × 360° / m) = (0.15 × 360° / 24) = 2.25°, which satisfies 0.6 × 2.2° = 1.32° < 2.25° < 2.2°.

[0069] Multiwavelength aberration testing: 486nm wavelength: maximum spherical aberration 0.10mm, field curvature 0.42% 587nm wavelength: maximum spherical aberration 0.09mm, field curvature 0.38% 656nm wavelength: maximum spherical aberration 0.11mm, field curvature 0.47%. Actual measurements show that this embodiment of the invention can form 288 clear maple leaf pattern light spots within a projection distance range of 2-15 meters, with a light spot uniformity of more than 90% and edge clarity that is significantly better than the comparative laser solution.

[0070] This utility model is applicable to various scenarios such as landscape lighting, ambient lighting, commercial displays, educational projection, and stage lighting.

[0071] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A dynamic multi-spot projection optical system based on an LED light source, characterized in that, The device includes an LED light source, a reflector, a grating sheet, a condenser lens, a concave mirror, and an optical reflection assembly. The LED light source is located at the bottom of the reflector, and the grating sheet is located above the LED light source. The grating sheet has a light-transmitting area with a preset pattern shape. The reflector is composed of several planar mirrors A, which are connected in sequence to form a conical reflective surface. The concave mirror is composed of several planar mirrors B. The optical reflection assembly reflects the light reflected from the reflector to the condenser lens, which focuses the light before reflecting it out by the concave mirror.

2. The dynamic multi-spot projection optical system based on an LED light source as described in claim 1, characterized in that, It also includes a grating turntable, which has several grating plates at the center of the ring turntable. The grating plates above the LED light source are switched by rotating the grating turntable.

3. The dynamic multi-spot projection optical system based on an LED light source as described in claim 1, characterized in that, The optical reflection assembly consists of a plane mirror A and a plane mirror B. The plane mirror A is positioned above the reflector, and the plane mirror B is positioned in front of the plane mirror A. The plane mirror A reflects the light reflected from the reflector to the plane mirror B, and then the plane mirror B reflects the light to the condenser lens.

4. The dynamic multi-spot projection optical system based on an LED light source as described in claim 3, characterized in that, A light-blocking plate is provided between the condenser lens and the reflector.

5. The dynamic multi-spot projection optical system based on an LED light source as described in claim 1, characterized in that, The condenser lens adopts a biconvex aspherical structure, where both its front and rear surfaces are even-order aspherical surfaces, and satisfy the following conditions: The focal length is 162.99mm±5%, the radius of curvature of the front surface is 26180mm±5%, the radius of curvature of the rear surface is 80.214mm±5%, the conicity of the front surface is k=37.527±5%, the conicity of the rear surface is k=-0.9545±5%, and the center thickness is 5.1325mm±5%.

6. The dynamic multi-spot projection optical system based on an LED light source as described in claim 5, characterized in that, The refractive index of the condenser lens is 1.493±5%, and the Abbe number is 57.2±5%.

7. The dynamic multi-spot projection optical system based on an LED light source as described in claim 1, characterized in that, The preset pattern shape is one or more of the following: maple leaf, snowflake, star, cloud, and swastika.

8. The dynamic multi-spot projection optical system based on an LED light source as described in claim 1, characterized in that, It also includes a rotary drive module, with a concave reflector correspondingly mounted on the output shaft of the rotary drive module.

9. The dynamic multi-spot projection optical system based on an LED light source as described in claim 1, characterized in that, A concave mirror is a parabolic mirror.

10. The dynamic multi-spot projection optical system based on an LED light source as described in claim 1, characterized in that, The reflector includes n planar mirrors A, and the concave reflector includes m planar mirrors B. The n+1 light spots reflected by the optical reflection components in a preset pattern shape are used as a projection unit. The dynamic multi-spot projection optical system based on an LED light source satisfies the following equation: 0.6× δ <(X×360° / m)< δ ; Where X represents the angular magnification of the entire optical system of the dynamic multi-spot projection optical system based on LED light source. δ The angular diameter of a single projection unit on the projection plane.

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