Minimally invasive medical devices are widely investigated, because of their advantages for in-situ medical examination in real time with highly reduced risk and patient discomfort, as compared to more traditional approaches. Optical biopsy is a prominent example of this trend and provides essential diagnostic information on tissue histopathology in the gastro-intestinal tract. Micro-electro mechanical system technology is demonstrated in this paper to be highly suitable for fabrication of an optical biopsy microsystem, where overall system dimensions and power consumption are key enabling factors. The biopsy microsystem presented is 11.2 mm in diameter and 18.6 mm in length and contains an imaging system with a dedicated image magnification optical microsystem (IMOM) and light emitting diodes (LEDs). Polydimethylsiloxane microlenses have been fabricated using the “hanging droplet” approach and integrated in the IMOM subsystem for achieving an image magnification by a factor 4 and a 30% improvement in optical irradiance from the LED illumination.@en

This paper reports on the development of a technology for the wafer-level fabrication of an optical Michelson interferometer, which is an essential component in a micro opto-electromechanical system (MOEMS) for a miniaturized optical coherence tomography (OCT) system. The MOEMS consists on a titanium dioxide/silicon dioxide dielectric beam splitter and chromium/gold micro-mirrors. These optical components are deposited on 45° tilted surfaces to allow the horizontal/vertical separation of the incident beam in the final micro-integrated system. The fabrication process consists of 45° saw dicing of a glass substrate and the subsequent deposition of dielectric multilayers and metal layers. The 45° saw dicing is fully characterized in this paper, which also includes an analysis of the roughness. The optimum process results in surfaces with a roughness of 19.76 nm (rms). The actual saw dicing process for a high-quality final surface results as a compromise between the dicing blade's grit size (#1200) and the cutting speed (0.3 mm s−1). The proposed wafer-level fabrication allows rapid and low-cost processing, high compactness and the possibility of wafer-level alignment/assembly with other optical micro components for OCT integrated imaging.@en