title: Laser Doppler blood flow complementary metal oxide semiconductor imaging sensor with analog on-chip processing.
abstract: A 4 x 4 pixel array with analog on-chip processing has been fabricated within a 0.35 mum complementary metal oxide semiconductor process as a prototype sensor for laser Doppler blood flow imaging. At each pixel the bandpass and frequency weighted filters necessary for processing laser Doppler blood flow signals have been designed and fabricated. Because of the space constraints of implementing an accurate omega(0.5) filter at the pixel level, this has been approximated using the "roll off" of a high-pass filter with a cutoff frequency set at 10 kHz. The sensor has been characterized using a modulated laser source. Fixed pattern noise is present that is demonstrated to be repeatable across the array and can be calibrated. Preliminary blood flow results on a finger before and after occlusion demonstrate that the sensor array provides the potential for a system that can be scaled to a larger number of pixels for blood flow imaging.
authors.affiliation: School of Electrical and Electronic Engineering, University of Nottingham, University Park, Nottingham, UK.
authors.forename: Quan
authors.initials: Q
authors.lastname: Gu
authors.forename: Barrie R
authors.initials: BR
authors.lastname: Hayes-Gill
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Morgan
mesh_terms: D000465:Algorithms; D001331:Automation; D002138:Calibration; D001330:Electronic Data Processing; D004867:Equipment Design; D006801:Humans; D017078:Laser-Doppler Flowmetry / Q000379:methods; D007834:Lasers; D008670:Metals / Q000737:chemistry*; D055095:Optics and Photonics; D010087:Oxides / Q000737:chemistry*; D019047:Phantoms, Imaging; D012666:Semiconductors; D014025:Titanium / Q000737:chemistry
chemical_list: D008670:Metals; D010087:Oxides; C009495:titanium dioxide; D014025:Titanium