Patent ID: 6023521
Filing Date: 2000-02-08
Classification: G06T

Abstract:
A circuit for determining the velocity of an image feature moving between a first and a second position, and between a first and a third position, comprising:a first circuit having first, second and third sensors, the first and second sensors being located on a first axis, the first and third sensors being located on a second axis, the first, second and third sensors for detecting the image feature in an image having a contrast in the first position, the second position and the third position, respectively, the first circuit generating a first signal, a second signal and a third signal in response to the detection of the image feature in the first position, the second position and the third positions, respectively; anda second circuit for converting the first signal to a fourth signal, the fourth signal being representative of the time lapse starting from the detection of the image feature at the first position, the second circuit generating a fifth signal in response to the second and fourth signals and a sixth signal in response to the third and fourth signals, the fifth signal being representative of the velocity of the image feature moving from the first position to the second position, and the sixth signal being representative of the velocity of the image feature moving from the first position to the third position, the fifth and sixth signals being independent of the contrast of the image.