A micro-mirror formed using excimer laser processing for a fluorinated polyimide waveguide film was demonstrated. The tilted excimer laser irradiation to the waveguide core formed a micro-mirror with an angle of 45 +/- 1-degree. The micro-mirror had convex profile and exhibited a lens effect as a concave mirror. The micro-mirror, as formed, exhibited a low reflection loss of approximately 0.6dB at a wavelength of 850nm. This technique applied to flexible optical and electrical circuit board.
Tsuyoshi Shioda, Tsuyoshi Shioda,
"Micro-mirror formed using excimer laser processing in a polymer waveguide", Proc. SPIE 5724, Organic Photonic Materials and Devices VII, (4 April 2005); doi: 10.1117/12.592060; https://doi.org/10.1117/12.592060