Point spread function engineering based on wavefront phase modulation

Point spread function (PSF) is the response of an optical system to a point source. The ideal PSF of traditional optics is Airy pattern corresponding to images without aberration. However, the PSF shape is considered to be flexible in computational imaging territory, which can be artificially manipulated, and the target image is restored by reconstruction algorithm. It is called PSF engineering and can improve the imaging quality of optical system. The method can break through traditional optical limitations and even endow optical systems with new imaging capabilities. In this paper, we will discuss PSF engineering method based on wavefront phase modulation, which is more commonly used for its advantage of high throughput. Its application, the depth of field extension of an in-situ plankton imaging system is discussed based on end-to-end joint optimization, demonstrating a defocus invariant imaging quality.