Development of a Laser Micromachining Process for the Fabrication of SiC Mirrors

The primary goal of this Phase 2 proposal is the construction of a multi-axis laser micromachining workstation for the fabrication of SiC mirrors and optical bench components to reduce both cost and long lead-times associated with current beryllium optics. Phase 1 results clearly indicated that laser micromachining can significantly reduce cost and increase the precision when compared to conventional contour grinding. One of the longest lead-time manufacturing processes is the mirror precision machining and subsequent polishing to achieve final figure and surface quality. This proposal details the tasks required for constructing a 9-axis automated micromachining workstation and verifying its ability to machine on-axis and off-axis complex mirrors to a figure and surface finish suitable for transitioning to a final polish operation. The combination of 6-axis motion system and 3-axis scanning system with an advanced laser system compose an unprecedented laser-based micromachining capability that does not exist today. This effort outlined in this proposal will develop a capability that extends the current state-of-the-art in laser micromachining. In addition to a 9-axis machining capability, the workstation will be automated to function in a 24/7 mode of operation and will include an integrated laser sensing technique for in situ metrology. Integrated metrology and process automation further reduce fabrication costs and maximizes overall process precision.