MODULATION TRANSFER FUNCTION TEST COMPENSATION FOR TEST PATTERN DUTY CYCLE

摘要

Improving accuracy of frequency response measurements of linear systems using modulation optical function test compensation. An optical imaging system (145) illuminates and images an input test pattern (143). A processor (84) measures a modulation transfer function. The processor (143) determines a compensating factor for error in the input test pattern duty cycle. The driving function for the measurement is a test pattern (143) having a periodic waveform approximating a square wave with an error in duty cycle. A windowed fast fourier transform on a greyscale image of the test pattern (143) generates odd harmonics corrects for the error in resolution target duty cycle.