CMOS Optical Sensors for being incorporated in Endoscopic Capsule for Cancer Cells Detection

Abstract — This paper describes the design, fabrication and characterization of CMOS optical sensors for cancer detection based on autofluorescence emission spectra. These optical sensors were fabricated for being an integrated part of an endoscopic capsule used in diagnosis of gastrointestinal diseases. Cells and tissues show autofluorescence, in a part of the visible spectrum, when excited by ultraviolet or short-wavelength visible light. The emission spectrum of cancer tissue is different from the one of the healthy tissue, and, it is dependent on the cancer development stage. CMOS photodetectors can be used to measure that spectrum. Once they are small and easily integrated with readout electronics, they can be placed around all the surface of the endoscopic capsule. While, nowadays, a locomotion and stop mechanism is a challenge, this scheme can cover a large area of the gastrointestinal tract examination during the natural movement of the capsule. The complete system will innovate the way of physicians diagnose the gastrointestinal diseases. I