Effect of Truncation of Line-Spread and Edge-Response Functions on the Computed Optical Transfer Function

The accuracy of optical transfer functions computed by Fourier transformation of the measured line-spread functions is limited by the necessary truncation of the line-spread functions. Error of the optical transfer function due to truncation of the line-spread function is given for various wave-front aberrations and for various degrees of truncation. The additional error introduced by sampling the truncated line-spread function at the Nyquist rate has been found to be very small. A procedure for reducing the error of the optical transfer function due to truncation of the line-spread function is given.