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Electro-optics system engineers often require the 2D optical point spread function (PSF) to predict a sensor’s system level performance. The 2D PSF is used to compute metrics like detection range and signal to noise (SNR) at the target, or to develop a matched filter algorithm to improve detection performance. Lens designers generate the 2D optical PSF using optical design tools like CODE-V or Zemax. If the systems engineer needs the PSF data at different field angles, the lens designer has to generate those results again resulting in a cumbersome interaction between these two disciplines. The problem gets exacerbated when going from narrow field of view (NFOV) optics to wide field of view (WFOV) optics where there can be significant differences in the PSF between the on-axis and the off-axis case. This is particularly relevant in the cases of WFOV threat warning and situational awareness infrared sensors where the on-axis Airy-disk model of the PSF is no longer valid for the large off axis angles experienced in those sensors. This paper will present the Zernike Math Model (ZMM) approach to generate 2D optics PSF outside the lens design platform and move the analysis to a more common scientific/engineering tool that systems engineers use. Once an optical design is completed by the lens designer, its performance can be represented by a unique set of Zernike polynomial coefficients. The ZMM approach will only require the lens designer to provide this set of coefficients once, and the system engineer can then use these data to model the optical PSF performance on and off-axis, using standard engineering analysis tools such as MATLAB or Mathcad. Once the optical PSF is known, it can be transformed into the modulation transfer function (MTF) form and used to model sensor performance. Our approach simplifies the interaction between systems engineering and optical engineering disciplines in helping translate optical performance into system level sensor performance modeling.
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