Novel semi-transparent optical position sensors ('ALMY sensors') have been
developed for the alignment monitoring systems of modern large-area trackin
g detectors. More than 10 sensors can be aligned along one laser beam. The
thin-film amorphous silicon strip sensors provide up to 90% transmittance f
or red laser light combined with minimum beam distortion and a typical posi
tion resolution of 1 mum over a sensitive area of several square centimeter
s. (C) 2001 Elsevier Science B.V. All rights reserved.