Laser polarization modulation double-beam surface printing system

Abstract

The invention discloses a laser polarization modulation double-beam surface printing system, which belongs to the technical field of laser printing, and comprises a light source and shaping module, a pattern modulation module I, a polarization modulation module, a pattern modulation module II and a forming module, the pattern modulation module I comprises an optical addressable light valve I; according to the surface area printing technology, laser is continuously emitted and continuously irradiated, a first optical addressable light valve and a second optical addressable light valve are used for conducting patterning polarization modulation on laser beams, and pattern indicating light can control the laser surface power and the exposure time by adjusting the gray level of each pixel; the surface area printing can better control the melting process, the printing resolution is improved, the printing material range is wide, support-free printing is carried out, splashing is eliminated, and the cost, the system complexity, the construction speed and the like are greatly improved.

Description

Technical Field

[0001] The invention belongs to the technical field of laser printing, and in particular relates to a laser polarization modulation double-beam surface printing system. Background Art

[0002] At present, most laser additive manufacturing equipment is based on pulsed laser for selective melting. Through the melting and superposition of powder layers, the forming from point to line, line to surface, and surface to body is realized. Even for surface printing, only one printing surface can be melted at a time, with low forming efficiency and small printing size; thus, the working efficiency of laser 3D printing is low. In order to improve the forming efficiency and size of the equipment, the commonly used method is to increase the number of lasers. However, on the one hand, the increase in the number of lasers means the introduction of new variables, which affects the stability and reliability of the overall equipment, and the increase in the number of lasers means the increase in the number of splicing areas. The more splicing areas there are, the more difficult it is to ensure the splicing quality, and the higher the risk of product quality problems. On the other hand, the introduction of multiple lasers not only increases the equipment cost, but also the number of galvanometers will increase with the increase in the number of continuous lasers. Accurate calibration and special thermal management are required for accurate printing, which will greatly increase the complexity of the system, which is not conducive to actual production applications. Therefore, a laser polarization modulated dual-beam surface printing system is needed to solve the above problems. Summary of the invention

[0003] The object of the present invention is to provide a laser polarization modulated dual-beam surface printing system to solve the problems raised in the above background technology.

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a laser polarization modulated dual-beam surface printing system, comprising a light source and shaping module, a pattern modulation module 1, a polarization modulation module, a pattern modulation module 2 and a molding module, the light source and shaping module comprising a continuous laser and a homogenizing device, the pattern modulation module 1 comprising an optically addressable light valve 1, the polarization modulation module comprising a polarization beam splitter and a 4 / λ glass slide, the pattern modulation module 2 comprising an optically addressable light valve 2 and a reflector, and the molding module comprising a scanning system.

[0005] The present invention performs polarization modulation on the laser light path so that the originally discarded light beam can also be used for laser additive processing and obtain regional printing results, so that the laser emitted by a continuous laser can act on two working surfaces at the same time to perform laser additive processing and obtain regional printing results, thereby realizing the melting and forming of two areas. In addition, the cost of polarization modulation is much lower than the cost of increasing the number of continuous lasers, and the working area is increased without increasing the number of continuous lasers, thereby improving the printing efficiency.

[0006] As a preferred solution, the continuous laser adopts a high-power continuous laser that can emit a continuous infrared light source (ie, a printing light source) to generate the printing light source.

[0007] As a preferred solution, the homogenizing device is used to shape, collimate and homogenize the printing light source.

[0008] As a preferred solution, the optically addressable light valve 1 is used to receive the collimated and homogenized laser beam and perform polarization modulation on the laser beam to generate a first laser carrying printing image information.

[0009] As a preferred solution, the polarization beam splitter is used to receive the first laser and perform polarization light filtering on the first laser, separate the S-polarized laser light that does not carry the printing image information in the first laser, and output the remaining P-polarized laser light that carries the printing image information in the first laser as the second laser.

[0010] As a preferred solution, the 4 / λ glass slide modulates the portion of the S-polarized laser light in the first laser that does not carry the printing image information, so that the portion of the S-polarized laser light that does not carry the printing image information is modulated into a P-polarized laser light as a third laser. The third laser light carries the printing pattern information and is output as a fourth laser light through an optically addressable light valve 2. The fourth laser light is reflected to the scanning system through a reflector.

[0011] As a preferred solution, the scanning system is used to receive the second laser and the fourth laser and perform regional reflection and focusing in a designated working area to obtain a printing result of the printing image information in the designated working area.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] The surface area printing technology of the present invention continuously emits laser light and irradiates continuously, and uses optically addressable light valve 1 and optically addressable light valve 2 to perform patterned polarization modulation on the laser beam, wherein the pattern indicator light can control the laser surface power and exposure time by adjusting the grayscale of each pixel, so that the surface area printing can better control the melting process, improve the printing resolution, print a wide range of materials, perform support-free printing, and eliminate splashes. Compared with traditional additive manufacturing equipment with a single laser, dual lasers, four lasers, or even more lasers, it has greatly improved the cost, system complexity, and construction speed.

[0014] The present invention adjusts the laser optical path so that the original waste light without printing pattern information can be reused, and the laser output power can be used to the maximum extent without increasing the continuous laser and at a low cost. The original waste light is reused for printing, so that one continuous laser can perform two-way printing at the same time, thereby improving printing efficiency.

[0015] The present invention combines the polarization modulation system with the optical rod system, so that the original emitted laser can act on two working surfaces at the same time to increase the printing area or act on one working surface alone, which can meet the requirements of large-size printing and small-size printing at the same time and improve printing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is the module connection diagram of the present invention;

[0017] Figure 2 Schematic diagram of the optical path of the present invention.

[0018] In the figure: 1. light source and shaping module; 11. continuous laser; 12. homogenization device; 2. pattern modulation module 1; 21. optically addressable light valve 1; 3. polarization modulation module; 31. polarization beam splitter; 32. 4 / λ glass; 4. pattern modulation module 2; 41. optically addressable light valve 2; 42. reflector; 5. shaping module; 51. scanning system. DETAILED DESCRIPTION

[0019] The present invention will be further described below in conjunction with the embodiments.

[0020] The following examples are used to illustrate the present invention, but they cannot be used to limit the scope of protection of the present invention. The conditions in the examples can be further adjusted according to specific conditions. Simple improvements to the method of the present invention under the premise of the concept of the present invention belong to the scope of protection claimed in the present invention.

[0021] See also Figure 1-2The present invention provides a laser polarization modulation dual-beam surface printing system, comprising a light source and shaping module 1, a pattern modulation module 2, a polarization modulation module 3, a pattern modulation module 4 and a molding module 5, wherein the light source and shaping module 1 comprises a continuous laser 11 and a homogenizing device 12, the pattern modulation module 2 comprises an optically addressable light valve 21, the polarization modulation module 3 comprises a polarization beam splitter 31 and a 4 / λ glass plate 32, the pattern modulation module 4 comprises an optically addressable light valve 41 and a reflector 42, the molding module 5 comprises a scanning system 51, the continuous laser 11 adopts a high-power continuous laser 11 capable of emitting a continuous infrared light source, i.e., a printing light source, for generating a printing light source, the homogenizing device 12 is used for shaping, collimating and homogenizing the printing light source, the optically addressable light valve 21 is used for receiving the collimated and homogenized laser beam, and polarization modulating the laser beam to generate a printing light source carrying a printing pattern. The first laser with image information, the polarization beam splitter 31 is used to receive the first laser and perform polarization light filtering on the first laser, separate the part of the S polarization direction laser that does not carry the printing image information in the first laser, and output the remaining part of the P polarization direction laser that carries the printing image information in the first laser as the second laser, the 4 / λ glass 32 modulates the part of the S polarization direction laser that does not carry the printing image information in the first laser, so that the part of the S polarization direction laser that does not carry the printing image information is modulated into the P polarization direction laser as the third laser, the third laser carries the printing pattern information and is output as the fourth laser through the optically addressable light valve 2 41, the fourth laser is folded into the scanning system 51 through the reflector 42, the scanning system 51 is used to receive the second laser and the fourth laser and perform regional reflection and focusing in the specified working area to obtain the printing result of the printing image information in the specified working area.

[0022] The system uses an optically addressable light valve to perform patterned polarization modulation on the laser beam, thereby obtaining a printing light spot with pattern information; the system uses a 4 / λ glass 32 to reuse and modulate waste light that does not carry printing information, so that the waste light can be modulated into laser light that carries printing information, thereby improving the utilization rate of the output power of the continuous laser 11; the system provides a method of increasing the printing area and improving the printing efficiency without increasing the number of continuous lasers 11.

[0023] The working principle and use process of the present invention are as follows: the continuous laser 11 can be a high-power continuous laser 11 capable of emitting a continuous infrared light source (i.e., a printing light source), and the homogenizing device 12 can be set as a collimating and homogenizing module. The continuous infrared light source generated by the continuous laser 11 completes beam shaping after passing through the collimating and homogenizing module, and obtains a square uniform collimated infrared light. The square infrared light is subjected to polarization modulation by an optically addressable light valve 21 and polarized light filtering by a polarizing beam splitter 31, and finally obtains a second laser carrying printing image information and a laser in the S polarization direction that does not carry printing image information;

[0024] The S-polarized laser beam without printing image information is incident on the 4 / λ glass plate 32 to obtain the P-polarized laser beam as the third laser beam, which is then modulated by the optically addressable light valve 2 41 to become the fourth laser beam carrying pattern information;

[0025] The second laser is directly incident on the scanning system 51, and the fourth laser is deflected by the reflector 42 and incident on the scanning system 51. The second laser and the fourth laser are used to print the print image in the corresponding area on the working surface, so as to perform regional printing of the product;

[0026] The laser beam P light carrying the printing information is directly redirected to the working surface for printing, and the laser beam not carrying the printing information is polarized modulated. After polarization modulation, the waste S light in the original optical path obtains the P polarization state, and then passes through the optically addressable light valve 2 41 so that the light in the S polarization direction carries the printing information. The reflection and focusing make the laser beam carrying the printing information act on two 300mm×300mm working surfaces. Through the control of the scanning system 51, additive laser processing can be performed on one working surface alone or on two working surfaces at the same time.

[0027] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A laser polarization modulated dual-beam surface printing system, comprising a light source and shaping module (1), a pattern modulation module 1 (2), a polarization modulation module (3), a pattern modulation module 2 (4) and a molding module (5), characterized in that: The light source and shaping module (1) comprises a continuous laser (11) and a homogenizing device (12), the pattern modulation module (2) comprises an optically addressable light valve (21), the polarization modulation module (3) comprises a polarization beam splitter (31) and a 4 / λ glass plate (32), the pattern modulation module (4) comprises an optically addressable light valve (41) and a reflector (42), and the shaping module (5) comprises a scanning system (51).

2. The laser polarization modulated dual-beam surface printing system according to claim 1, characterized in that: The continuous laser (11) is a high-power continuous laser (11) capable of emitting a continuous infrared light source (i.e., a printing light source) and is used to generate a printing light source.

3. The laser polarization modulated dual-beam surface printing system according to claim 1, characterized in that: The homogenizing device (12) is used to shape, collimate and homogenize the printing light source.

4. The laser polarization modulated dual-beam surface printing system according to claim 1, characterized in that: The optically addressable light valve 1 (21) is used to receive the collimated and homogenized laser beam and to perform polarization modulation on the laser beam to generate a first laser beam carrying printing image information.

5. The laser polarization modulated dual-beam surface printing system according to claim 1, characterized in that: The polarization beam splitter (31) is used to receive the first laser and perform polarization filtering on the first laser, separate the S-polarized laser light that does not carry the printing image information in the first laser, and output the remaining P-polarized laser light that carries the printing image information in the first laser as the second laser.

6. The laser polarization modulated dual-beam surface printing system according to claim 1, characterized in that: The 4 / λ glass plate (32) modulates the portion of the S-polarized laser light in the first laser light that does not carry the printed image information, so that the portion of the S-polarized laser light that does not carry the printed image information is modulated into a P-polarized laser light as a third laser light. The third laser light carries the printed pattern information and is output as a fourth laser light through an optically addressable light valve 2 (41). The fourth laser light is folded into a scanning system (51) through a reflector (42).

7. The laser polarization modulated dual-beam surface printing system according to claim 1, characterized in that: The scanning system (51) is used to receive the second laser and the fourth laser and perform regional reflection and focusing in a designated working area to obtain a printing result of the printing image information in the designated working area.

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