Improvements to spectral spot-scanning technique for accurate and efficient data acquisition

Abstract

An improved and optimized spectral spot-scanning system for visible focal plane array (FPA) sub-micron pixel photoresponse testing is presented. This updated configuration includes: (1) additional diagnostic analysis tools which more completely characterize the operation of the system; (2) a confocal microscope fitted into the optical system to aid in more precise determination of spot focusing on the imager; (3) a post-acquisition transformation to imager pixel response data to reduce overall data acquisition time. Wavelength-dependent pixel response data is presented to demonstrate the repeatability of this setup as well as to quantify the impact of random and systematic experimental errors.

Simulation and experimental characterization of the point spread function, pixel saturation, and blooming of a mercury cadmium telluride focal plane array

“…The PSF measured directly by the spot scanning experiment, PSF measured , differs from the actual PSF, PSF detector , because the spot used for the measurement is not infinitely small. The relation of the two is [2] PSF measured PSF optics PSF detector ;…”

“…The modulation transfer function (MTF) is also computed by performing a Fourier transform on the PSF [4]. The relation of the detector MTF to the measured MTF is [2] MTF measured MTF optics · MTF detector :…”

“…The position of the spot is controlled by motorized translation stages. This experiment allows for direct measurement of the point spread function (PSF) of the detector [1,2], which is a pixel's response to point illumination as a function of position in the plane of the detector. The PSF depends on the physics of charge diffusion in conjunction with the pixel geometry and location of the illumination.…”