Title :
Modulation transfer function (MTF) analysis for a FLIR system with nonlinear video electronics
Author :
Orlando, Harold ; Luu, Thanh
Author_Institution :
Div. of Electron. Syst., Northrop Corp., Hawthorne, CA, USA
Abstract :
The image formation process of forward looking infrared (FLIR) systems differs from system to system with some systems utilizing gamma correction in the electronics. This is done to compensate for display nonlinearity referred to as the display gamma. Automated minimum resolvable temperature (MRT) testing for an automated support system requires modulation transfer function (MTF) measurement data collected at the video output. To compute the MTF the time averaged edge trace is differentiated digitally to produce the line spread function (LSF) and the FFT. The gamma correction introduced in the video signal for display purposes may introduce errors in the MTF measurement and should be removed for a more accurate result. These nonlinear effects are investigated using simulations and actual measurement data from a FLIR system. The results from the analysis provide one with data for designing improved testing procedures
Keywords :
automatic testing; digital simulation; electronic engineering computing; electronic equipment testing; fast Fourier transforms; image processing; image sensors; infrared detectors; measurement errors; optical transfer function; optical variables measurement; FFT; FLIR; MTF; automated support system; display gamma; display nonlinearity; errors; forward looking infrared systems; gamma correction; image formation process; line spread function; minimum resolvable temperature; modulation transfer function; nonlinear effects; nonlinear video electronics; simulation; video signal; Automatic testing; Data analysis; Displays; Error correction; Infrared imaging; Signal resolution; System testing; Temperature; Transfer functions; Voltage;
Conference_Titel :
Aerospace and Electronics Conference, 1993. NAECON 1993., Proceedings of the IEEE 1993 National
Conference_Location :
Dayton, OH
Print_ISBN :
0-7803-1295-3
DOI :
10.1109/NAECON.1993.290796
