Tektronix, Inc.

Harvey Leon Golladay

Michael L Rieger

Kenneth G Schlotzhauer

Carl R Battjes

Binoy Anthony Rosario

A stepping motor generates first and second voltages each varying in accordance with a sinusoidal function having a period proportional to the period of rotation of the motor's rotor, the first and second voltages being in quadrature with each other. A control device generates from the first and second voltages a signal representative of a number that is proportional to the square root of the sum of the squares of the first and second voltages. This signal is used to modify the energizing current provided to the phase windings of the stator, in order to reduce fluctuations in torque and shaft angular velocity.

Control devices for use with a stepping motor

A circuit to correct for pincushion distortion and defocusing in a cathode-ray tube having electromagnetic deflection systems is disclosed. The circuit, which may be realized in monolithic integrated-circuit form, performs a mathematical function to predistort the deflection signal for each axis by the amount necessary to provide an undistorted display. The circuit also provides a signal to correct for the defocusing that occurs at the edges of the screen. The circuit may be readily adapted for use with cathode-ray tubes having different diagonal deflection angles, and with either flat of curved faceplates, by changing the values of two resistors.

Growing community of inventors

Beaverton, OR, United States of America

Harvey Leon Golladay