Method for optimum focusing of electro-optical sensors for testing purposes with a haar matrix transform

A method of optimizing an optical focus of an electro-optical sensor in preparation for accurately measuring an optical parameter thereof of the type including, but not limited to, dynamic range, modulation transfer function, minimum resolvable temperature difference and field of view, said method comprising:

• changing a focus of said sensor on a target image viewed by said sensor while obtaining successive output images produced by said sensor;
• constructing respective image vectors from respective ones of said output images;
• for each one of said image vectors, transforming said image vector by a transform to produce a transformed image vector of elements whose values correspond to spatial frequency content;
• computing a sum of squares of the elements of each said transformed image vector to produce a corresponding focus metric;
• and
• identifying the focus of said sensor for the obtained output image corresponding to a maximum one of said produced focus metrics as being the optimized optic focus.