Extending depth of field for hybrid imaging systems via the use of both dark and dot point spread functions.

In this paper, we propose one method based on the use of both dark and dot point spread functions (PSFs) to extend depth of field in hybrid imaging systems. Two different phase modulations of two phase masks are used to generate both dark and dot PSFs. The quartic phase mask (QPM) is used to generate the dot PSF. A combined phase mask between the QPM and the angle for generating the dark PSF is investigated. The simulation images show that the proposed method can produce superior imaging performance of hybrid imaging systems in extending the depth of field.