Illumination system for 3D precision printing

Abstract

The application relates to a lighting system for 3D accurate printing, belonging to the technical field of micro projection display, which comprises an LED light source, a collimation mechanism, a light homogenizing mechanism, a relay lens group, a TIR prism and a digital micro mirror, light emitted by the LED light source passes through the collimation mechanism, the light homogenizing mechanism, the relay lens group and the TIR prism in sequence to reach the digital micro mirror, is processed by the digital micro mirror, is reflected to the TIR prism, is turned by the TIR prism, and reaches a projection lens. The lighting system has high energy utilization rate, high uniformity, small volume and simple and efficient assembly.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of micro projection display, and particularly relates to an illumination system for 3D accurate printing. BACKGROUND

[0002] With the continuous development of 3D printing technology, more and more end customers choose products taking TIDLP technology as the core, and TI has launched a 1080P version 0.47DMD, which requires the illumination system to also keep pace with the times, to achieve higher uniformity, higher efficiency and higher brightness.

[0003] The patent document with the publication number CN 107577111 A discloses an illumination light path system of a 3D printing optical projection device, the system comprising: a lens, a DMD chip, a reflector, a lens group and an LED light source; the first optical axis of the outgoing light rays of the lens coincides with the DMD chip; the second optical axis of the incident light rays of the DMD chip passes through the geometric center of the reflector; the third optical axis of the LED light source passes through the geometric center of the emission mirror; the second optical axis of the incident light rays of the DMD chip and the third optical axis of the LED light source form an optical path plane; the reflecting surface of the reflector is perpendicular to the second optical axis and the third optical axis on the angle bisector of the optical path plane; the third optical axis of the LED light source coincides with the fourth optical axis of the lens group; the light rays emitted by the LED light source pass through the lens group, are incident to the reflector, are reflected by the reflector and are incident to the DMD chip, are reflected by the micromirrors on the DMD chip and are incident to the lens again, which can improve the image quality of the lens and enhance the picture contrast. However, the illumination system of the application has poor light illumination uniformity.

[0004] The patent document with the publication number CN 216330128 U discloses a high-efficiency and high-uniformity illumination system for 3D printing, which is composed of a collimation structure, a light homogenization structure and a DMD chip. The collimation structure comprises a UV LED, a collimation lens A and a collimation lens B, wherein the collimation lens A is arranged in close contact with the UV LED, and the collimation lens B is arranged on the other side of the collimation lens A; the light homogenization structure comprises the collimation lens B and a light rod, and the light rod is positioned at the waist position of the outgoing light beam of the collimation structure. The light beam is sequentially incident to the DMD chip after passing through the field lens A, the field lens B, the field lens C and the light splitting prism. However, the light illumination uniformity and efficiency of the illumination system need to be further improved. SUMMARY

[0005] Therefore, the application provides an illumination system for 3D accurate printing, which improves the uniformity, brightness and efficiency.

[0006] To solve the above technical problems, the technical scheme adopted by the present application is: a lighting system for 3D precision printing, comprising an LED light source, a collimation mechanism, a light homogenizing mechanism, a relay lens group, a TIR prism and a digital micro mirror, light emitted by the LED light source passes through the collimation mechanism, the light homogenizing mechanism, the relay lens group and the TIR prism in sequence to reach the digital micro mirror, is processed by the digital micro mirror, is reflected to the TIR prism, is turned by the TIR prism, and then reaches a projection lens.

[0007] Further, the LED light source is a 405nm monochromatic light source.

[0008] Further, the collimation mechanism is composed of a first collimation lens and a second collimation lens, which are used to convert the light beam emitted by the LED light source into a parallel collimated light beam.

[0009] Further, the light homogenizing mechanism is composed of a first compound eye lens and a second compound eye lens, which are used to homogenize the collimated light beam to form a uniform light spot consistent with the shape of the digital micro mirror.

[0010] Further, the relay lens group is composed of a first relay lens and a second relay lens, and the second relay lens is a glass aspherical lens.

[0011] Further, the TIR prism is composed of a first prism and a second prism that are glued at an angle, the inner angle of the first prism is 31°, 90° or 59°, and the inner angle of the second prism is 45°, 90° or 45°.

[0012] Further, the first collimation lens is a glass spherical lens, and the second collimation lens is a glass aspherical lens.

[0013] Further, a mirror is arranged between the first relay lens and the second relay lens.

[0014] Further, the angle of light passing through the collimation mechanism is 7°.

[0015] Compared with the prior art, the present application has the following advantages:

[0016] 1. The lighting system for 3D precision printing of the present application uses a 405nm monochromatic light source as the LED light source to provide a light energy source, the light passes through the collimation mechanism to reach the light homogenizing mechanism, is homogenized by the light homogenizing mechanism, the light spot is uniform and consistent with the shape of the digital micro mirror, passes through the relay lens group, the TIR prism and reaches the digital micro mirror, is processed by the digital micro mirror, is reflected to the TIR prism, is turned by the TIR prism, and then reaches the projection lens to form an image, the design scheme of the lighting system has high energy utilization rate, high uniformity of illumination and simple and efficient assembly.

[0017] 2.The lighting system for 3D precision printing of the present application, the collimation mechanism is composed of a glass spherical collimation lens and a glass aspherical collimation lens, which is used to convert the light beam emitted by the LED light source into a parallel collimated light beam, the light angle of the collimation mechanism is 7°, the light angle of the whole system is small, and the light efficiency is high.

[0018] 3.The lighting system for 3D precision printing of the present application, the light uniformity of the whole system is improved by using a double compound eye lens module, in addition, the relay lens group is composed of a first relay lens and a second relay lens, the second relay lens is a glass aspherical lens, so that the energy distribution trend of the DMD surface presents as low in the center and high in the periphery, which makes up for the lens periphery illuminance ratio in the actual process, greatly improves the energy uniformity, and the point illuminance uniformity of the projection surface reaches 95%.

[0019] 4.The lighting system for 3D precision printing of the present application, a reflector is arranged between the first relay lens and the second relay lens, the light path is reflected by the reflector, so that the overall structure of the lighting system is reasonable and the volume is small. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a structural schematic diagram of the embodiment of the present application;

[0021] Figure 2 is a light path diagram of the embodiment of the present application;

[0022] Figure 3 is a light spot diagram of the embodiment of the present application on the DMD effective surface;

[0023] Figure 4 is a light spot diagram of the embodiment of the present application on the projection screen. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clear, the technical scheme of the embodiments of the present application will be described clearly and completely below in combination with the drawings of the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all the embodiments. Based on the described embodiments of the present application, all other embodiments obtained by those skilled in the art belong to the scope of protection of the present application.

[0025] Embodiment 1

[0026] As Figures 1-2As shown, a kind of illumination system for 3D precision printing, including LED light source 1, collimation mechanism, light uniformity mechanism, relay lens group, TIR prism and digital micro mirror 2, the light emitted by the LED light source 1 in turn collimation mechanism, light uniformity mechanism, relay lens group, TIR prism reaches the digital micro mirror 2, after the digital micro mirror 2 processing, it is reflected to the TIR prism, after the TIR prism turns, light reaches projection lens.

[0027] The LED light source 1 is a 405nm monochromatic light source for providing light energy source.

[0028] The digital micro mirror 2 is TI1080P version 0.47DMD.

[0029] The collimation mechanism is composed of first collimating lens 3 and second collimating lens 4, for converting the light beam emitted by the LED light source into parallel collimated light beam;The first collimating lens 3 is a glass spherical lens, and the second collimating lens 4 is a glass aspherical lens;The collimating lens detailed parameters are as follows:

[0030] radius of curvature R1 radius of curvature R2 first collimator lens -15 -6.5 second collimator lens 68.184 (aspherical) -10.117 (aspherical)

[0031] The light angle of the collimation mechanism is 7°, and the light angle of the whole system is small, and the light efficiency is high.

[0032] The light uniformity mechanism is composed of first compound eye lens 5 and second compound eye lens 6, for uniform light collimated light beam, forming uniform light spot consistent with the shape of the digital micro mirror;The first compound eye lens 5 and the second compound eye lens 6 have the same parameters, and the detailed parameters are as follows: compound eye unit R1=4.3, R2=INF, 10 columns * 18 rows.

[0033] The relay lens group is composed of first relay lens 7 and second relay lens 8, and the second relay lens 8 is a glass aspherical lens;The detailed parameters of the relay lens are as follows:

[0034] radius of curvature R1 radius of curvature R2 first relay lens 32.915 INF second relay lens 19.607 (aspherical) 28.188 (aspherical)

[0035] The first relay lens 7 and the second relay lens 8 are provided with mirror 9.

[0036] The TIR prism is composed of first prism 10 and second prism 11 which are glued with inclined plane, the inner angle of the first prism 10 is 31°, 90°, 59°, and the inner angle of the second prism 11 is 45°, 90°, 45°.

[0037] The illumination system for 3D precision printing of the embodiment of the application is tested, and the results are as shown in Figure 3 、 Figure 4 As shown.

[0038] The illumination system for 3D accurate printing of the embodiment of the present application improves the illumination uniformity of the whole system by using a double compound eye lens module, in addition, the second relay lens in the relay lens group is a glass aspheric lens, so that the DMD surface energy distribution trend presents as low in the center and high in the periphery, which makes up for the lens periphery illumination ratio in the actual process, greatly improves the energy uniformity, according to Figure 3 It can be known that the point illumination uniformity of the projection surface reaches more than 95%.

[0039] The above is the preferred embodiment of the present application, it should be pointed out that for the ordinary skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. An illumination system for 3D precision printing, characterized in that: The LED light source, collimation mechanism, light uniformization mechanism, relay lens group, TIR prism and digital micro mirror are included, light emitted by the LED light source passes through the collimation mechanism, light uniformization mechanism, relay lens group and TIR prism in sequence to reach the digital micro mirror, is processed by the digital micro mirror, reflected to the TIR prism, and turned by the TIR prism, and then reaches the projection lens; The LED light source is a 405nm monochromatic light source; The collimation mechanism is composed of a first collimation lens and a second collimation lens, and is used for converting the light beam emitted by the LED light source into parallel collimated light beams; the first collimation lens is a glass spherical lens, and the second collimation lens is a glass aspherical lens; the curvature radius R1 of the first collimation lens is -15, the curvature radius R2 is -6.5, the curvature radius R1 of the second collimation lens is 68.184, and the curvature radius R2 is -10.117; the light angle passing through the collimation mechanism is 7°; The light uniformization mechanism is composed of a first compound eye lens and a second compound eye lens, and is used for uniformizing the collimated light beams to form uniform light spots consistent with the shape of the digital micro mirror; the first compound eye lens and the second compound eye lens have the same parameters, and the parameters are as follows: compound eye unit R1=4.3, R2=INF, 10 columns*18 rows; The relay lens group is composed of a first relay lens and a second relay lens, and the second relay lens is a glass aspherical lens; the curvature radius R1 of the first relay lens is 32.915, the curvature radius R2 is INF, the curvature radius R1 of the second relay lens is 19.607, and the curvature radius R2 is 28.188; a mirror is arranged between the first relay lens and the second relay lens; The TIR prism is composed of a first prism and a second prism which are glued at an angle, the inner angle of the first prism is 31°, 90° and 59°, and the inner angle of the second prism is 45°, 90° and 45°; The digital micro mirror is a TI1080P version 0.47DMD.

Images