Research On Fabrication Of MOE Based On Digital Mask And SLA Technology

With the rapid development of optoelectronic technology, and the development trends of optical-mechanical-electrical integration, optical system and its components put forward the requirements of the application of miniaturization, array and integration. Micro-optical elements (abbr. MOEs) have advantages of small volume, light weight and low cost, and they can realize the functions which the common hardly reach, such as microminiature, array, integration, transformation of arbitrary wave plane and so on. MOEs have become the key component of micro-optoelectronic system. At present, methods of fabricating MOEs are mainly based on the photolithography of mask and maskless, basic production process from the microelectronics plane processing technology of large-scale integrated circuits. There are some limits of making the MOEs with complex structure and three-dimensional relief. But rapid prototyping technology is a new advanced manufacturing technology, applying the technology in the micro-fabrication field, can well realize the fabrication of components with3D complex structure.In this paper, a new method of fabricating MOEs based on digital mask technology and Stereo lithograpy Appratus(SLA) technology is mainly studied, called digital mask molding technique, which is using the output image of digital micromirror device (abbr. DMD), the MOEs can be obtained after reduction exposure to photosensitive resin, layered curing and superposition molding. Overcoming the shortage of traditional method in making the MOEs with complex structure and three-dimensional relief, and fabricating requirements of the integration application. Main research work is as follows:Firstly, perfected and designed a set of fabricating MOEs system based on digital mask molding technique, mainly including UV curing light, DMD digital mask projection device, stepping motor micro feed precision device, molding device, and the corresponding performance analysis.Secondly, make out the corresponding process according to the study, choose the making environment, coating process and photosensitive resin, study the key process of the system, including experimental measurement of the characteristics parameters of photosensitive resin, the design and adjustment of the light path, then test the light path by the exposure curing, and fabrication experiments of saval familiar MOEs.At last, experiment on some MOEs such as ronchi grating, fresnel lens, blazed grating. Experimental results prove the process feasible. And analyze, evaluate the error of equipment and process, put forward the corresponding solution measure to improve machining accuracy of the elements.According the study, the process has the advantages of simple structure, low cost and high efficiency compared with the traditional SLA, can achieve any diffractive three-dimensional structure manufacture, flexible fabrication. So it’s significant for the development of MOEMS.