Biomedical optical impedance sensors involve image processing of light blobs to extract information regarding a process such as pressure. These sensors utilize a light source to illuminate an imager chip. The edges of the light blob, its diameter and location are parameters of interest to characterize pressure dynamics. CMOS technology allows the capture and processing of an image on a single chip. However, specialized imagers, optimized for extracting dynamic information from light blobs for this application, have not been proposed. A CMOS active pixel sensor (APS) imager, capable of processing all parameters of interest in a light blob, is presented. Innovative, efficient and easy-to-implement techniques for cross-sectional diameter estimation and edge detection are proposed. The simulation results showed the feasibility of the proposed design. This chip was designed using 0.18 /spl mu/m technology and is currently being fabricated. It operates at 1.8 V.
['J.L. Gonzalez', 'Daniel C. Sadowski', 'Karan V. I. S. Kaler', 'Martin P. Mintchev', 'Orly Yadid-Pecht']
A CMOS imager for light blobs detection and processing