ENHANCED DIGITAL LIGHT PROCESSING-BASED MASK PROJECTION STEREOLITHOGRAPHY METHOD AND APPARATUS

• US 20170326786A1
• Filed: 08/01/2017
• Published: 11/16/2017
• Est. Priority Date: 12/30/2015
• Status: Active Grant

• Current Assignee: Han's Laser Technology Industry Group Co., Ltd.
• Original Assignee: Han's Laser Technology Industry Group Co., Ltd.
• Inventors: Yuan, Jian, Li, Xilu, Qi, Yangting, Yang, Hao, Gao, Yunfeng
• Granted Patent: US 10,639,843 B2
• Time in Patent Office: Days
• CPC Class Codes: B29C 2035/0838 using laser
• CPC Class Codes: B29C 35/0805 using electromagnetic radiation
• CPC Class Codes: B29C 64/129 characterised by the energy source therefor, e.g. by global irradiation combined with a mask
• CPC Class Codes: B29C 64/135 the energy source being concentrated, e.g. scanning lasers or focused light sources
• CPC Class Codes: B29C 64/268 using laser beams; using electron beams [EB]
• CPC Class Codes: B29C 64/393 for controlling or regulating additive manufacturing processes
• CPC Class Codes: B29K 2105/0058 Liquid or visquous
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 30/00 Apparatus for additive manufacturing; Details thereof or accessories therefor
• CPC Class Codes: B33Y 50/02 for controlling or regulating additive manufacturing processes

Abstract

An enhanced digital light processing-based mask projection stereolithography method and apparatus are disclosed, where the apparatus comprises: a control platform capable of slicing a model of a to-be-prototyped object into layers, converting the layer into a bitmap, and further dividing the layer into a main body area and boundary filling areas; a digital light processing unit that is controlled by the control platform and capable of emitting a first light beam used for the corresponding main body area of the layer of the to-be-prototyped object; and a laser marking unit that is controlled by the control platform and capable of emitting a second light beam used for the corresponding boundary filling areas of the layer of the to-be-prototyped object. The present invention can not only implement high-speed prototyping but also avoid an edge distortion, thereby improving precision of object prototyping.

Claims

1. An enhanced digital light processing-based mask projection stereolithography apparatus (20), comprising:

a control platform (206) capable of slicing a model of a to-be-prototyped object into layers, converting a layer into a bitmap, and further dividing the layer into a main body area (301) and boundary filling areas (305, 306, 307, 308);

a digital light processing unit (203) that is controlled by the control platform (206) and capable of emitting a first light beam (208) used for the corresponding main body area (301) of the layer of the to-be-prototyped object; and

a laser marking unit (205) that is controlled by the control platform (206) and capable of emitting a second light beam (209) used for the corresponding boundary filling areas (305, 306, 307, 308) of the layer of the to-be-prototyped object.

2. The apparatus according to claim 1, wherein an optical axis of the first light beam (208) is coaxial with an optical axis of the second light beam (209).

3. The apparatus according to claim 1, wherein prototyping the main body area (301) by the digital light processing unit (203) and prototyping the boundary filling areas (305, 306, 307, 308) by the laser marking unit (205) are performed simultaneously.

4. The apparatus according to claim 3, further comprising:

a dichroic mirror (204), wherein the first light beam (208) enters at an angle of 45 degrees to a first face of the dichroic mirror (204) and is reflected to a first specified processing position, and the second light beam (209) enters a second face of the dichroic mirror (204), penetrates the first face, and reaches a second specified processing position.

5. The apparatus according to claim 4, further comprising:

a prototyping platform (201) and a liquid resin tank (202) which is defined on the prototyping platform (201), wherein both the first specified processing position and the second specified processing position are located in the liquid resin tank (202).

6. The apparatus according to claim 5, wherein the first specified processing position is corresponding to the main body area (301), and the second specified processing position is corresponding to the boundary filling areas (305, 306, 307, 308).

7. The apparatus according to claim 5, wherein the prototyping platform (201) comprises a platform body and a moving mechanism that is configured to drive the platform body to move along a vertical axis.

8. The apparatus according to claim 1, wherein the laser marking unit (205) comprises a laser (2051), and the laser is an ultraviolet laser.

9. An enhanced digital light processing-based mask projection stereolithography method, comprising the following steps:

slicing a model of a to-be-prototyped object into layers, converting a layer into a bitmap, and further dividing the layer into a main body area and boundary filling areas;

prototyping, by using a digital light processing unit, the corresponding main body area of the layer of the to-be-prototyped object; and

prototyping, by using a laser marking unit, the corresponding boundary filling areas of the layer of the to-be-prototyped object.

10. The method according to claim 9, wherein the steps of slicing a model of a to-be-prototyped object into layers, converting a layer into a bitmap, and further dividing the layer into a main body area and boundary filling areas comprise:

performing lamination and slicing processing on a three-dimensional model of the to-be-prototyped object to obtain a series of vector sections composed of closed loops;

mapping the vector sections to an image area of a corresponding resolution of the digital light processing unit, and converting pixels located inside the closed loops into a bitmap, namely, the main body area; and

recording coordinates of a pixel intersecting with a boundary of the closed loop and an intersecting point between the pixel and the boundary of the closed loop to obtain the boundary filling areas.

11. The method according to claim 9, wherein prototyping the main body area by the digital light processing unit and prototyping the boundary filling areas by the laser marking unit are performed simultaneously.

12. The method according to claim 10, wherein the prototyping the corresponding boundary filling areas of the layer of the to-be-prototyped object by the laser marking unit comprises:

scanning filling lines inside the boundary filling areas and scanning contours of the boundary filling areas.

13. The method according to claim 10, wherein when a projection resolution of the digital light processing unit makes a corresponding size of the pixel smaller than a spot of the second light beam emitted by the laser marking unit, the prototyping the corresponding boundary filling areas of the layer of the to-be-prototyped object by the laser marking unit merely refers to scanning contours of the boundary filling areas.