It had been proved that MTF plays a key role in evaluation the quality of imaging system even in infrared spectral bands. Two methods of MTF test procedures have been used widely in visible domain, i.e. the direct method which is based on measuring the response to sinusoidal; and the indirect method, which is based upon computing the Fourier transform of the measured line spread function. However it can also be used in infrared spectral bands even in the evaluation of the system with staring arrays. But there is still something different in infrared imaging system. The infrared flux will be influenced by many factors such as: optimum focus, not normalized to zero spatial frequency properly, signal out of linear region, blackbody or ambient temperature changes during the test, S/N ratio and the width of the slit on the sensor's surface. Concerning the applications of staring arrays system both MRTD and MTF are the main factors in the target acquisition characteristics in infrared wavebands. So the MTF test could be implemented on fixed special frequency, for example 20lp/mm, We will deal with the influence of illumination on sensor with SRF (slit response function) method under a special frequency.
[1]
J. C. Fontanella,et al.
The Definition of the OTF and the Measurement of Aliasing for Sampled Imaging Systems
,
1982
.
[2]
Stephen E. Reichenbach,et al.
Characterizing digital image acquisition devices
,
1991
.
[3]
G. Cardone,et al.
Modulation transfer function cascade model for a sampled IR imaging system.
,
1991,
Applied optics.
[4]
Gerald C. Holst,et al.
Testing and evaluation of infrared imaging systems
,
1993
.
[5]
Javier Alda,et al.
Principal-component characterization of noise for infrared images.
,
2002,
Applied optics.