Thomas (Bromley, Kent, UK) Williams 
The Optical Transfer Function of Imaging Systems [PDF ebook] 

The Optical Transfer Function of Imaging Systems deals extensively with the theoretical concept of the optical transfer function (OTF), its measurement, and application to imaging devices. The OTF is a mathematical entity describing how well the subject is transferred into an image via the lens.
The book focuses on the practical aspects of using and measuring the OTF. It presents the background physics necessary to understand and assess the performance of the great proliferation of electro-optical systems, including image intensifiers, video cameras, and thermal imagers.
Assuming a senior undergraduate level of optics knowledge, the book is suitable for graduate courses in optics, electro-optics, and photographic science. In addition, it is a practical guide for systems designers who require a means of assessing and specifying the performance of imaging systems. It is also of interest to physicists and engineers working in all areas of imaging.