Optical finger movement monitor
祐司 久米, Hitoshi Ohzu · Clinical Physics and Physiological Measurement · 1982
By using a pair of phototransistors and differential amplification, a simple and inexpensive apparatus to measure the minute motion of a human fingertip with high accuracy and with high signal-to-noise ratio has been designed. It has been established that this apparatus is very useful for the study of finger movement function when the blind read with Optacon.