A novel optical self-alignment technology for realization of compact optical multi-gas sensor system

In this paper, a novel optical self-alignment technology for realization of compact optical multi-gas sensor system is newly proposed. This technology realizes high precision alignment of discrete optical components on a single silicon chip or combined multi silicon chips. Designing the optical path in parallel to the surface of silicon chip, discrete optical lenses and fibers are interconnected with a MEMS optical spectrometer and mirrors to form a compact optical gas detector system in a small size. Also, "height" of optical components can be adjusted to the optical axis by stacking the precisely aligned silicon chips. Micro optical system was fabricated using the developed alignment technology, and the position alignment error in in-plane direction (X- and Y-axis) was with in ±1μm in maximum. On the other hand, the maximum position error in out-of-plane direction (Z-axis) was below ±20μm. These values are high enough to fabricate our on-chip micro optical sensor system.