We demonstrate the ability to measure the system modulation transfer function (MTF) of both color and monochrome charge-coupled-device (CCD) video camera systems with a liquid-crystal-display (LCD) projector. Test matrices programmed to the LCD projector were chosen primarily to have a flat power spectral density (PSD) when averaged along one dimension. We explored several matrices and present results for a matrix produced with a random-number generator, a matrix of sequency-ordered Walsh functions, a pseudorandom Hadamard matrix, and a pseudorandom uniformly redundant array. All results are in agreement with expected filtering. The Walsh matrix and the Hadamard matrix show excellent agreement with the matrix from the random-number generator. We show that shift-variant effects between the LCD array and the CCD array can be kept small. This projector test method offers convenient measurement of the MTF of a low-cost video system. Such characterization is useful for an increasing number of machine vision applications and metrology applications.
© 2000 Optical Society of America
(040.1520) Detectors : CCD, charge-coupled device
(110.4100) Imaging systems : Modulation transfer function
(120.2040) Instrumentation, measurement, and metrology : Displays
(150.0150) Machine vision : Machine vision
Brian T. Teipen and Duncan L. MacFarlane, "Liquid-crystal-display projector-based modulation transfer function measurements of charge-coupled-device video camera systems," Appl. Opt. 39, 515-525 (2000)