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Wavefront coding has long offered the prospect of mitigating optical aberrations and extended depth of field, but image quality and noise performance are inevitably reduced. We report on progress in the use of agile encoding and pipelined fusion of image sequences to recover image quality.

Decoupling the illumination from the detection optics in microscopy can be achieved by combining light sheet and wavefront coding. This results in a system that allows the light sheet to produce optical sections from out of focus planes. By scanning the light sheet through the sample, it is possible to produce high-resolution volumetric images of living samples at unprecedented speeds.

We compare the performance of phase masks in the presence of third order aberrations. The cubic phase mask shows better performance for astigmatism while the quartic phase mask is more robust to coma.

We analyze the effects of aliasing and sampling phase on the PTF of sampled imaging systems. We present an image-based PTF estimation method and propose through-focus PTF as a tool for characterizing wavefront coding imagers.

The spatial frequency response of cubic phase mask wavefront coding imagers under extreme defocus conditions is experimentally measured. The results are compared against analytically derived expressions for optical transfer functions of these computational imaging systems.

Optical-digital hybrids are able to increase defocus tolerance; however, choosing the optimal pupil phase modulation is non-trivial. We show how hybrid imaging fidelity can be predicted and compare some of the most common phase-functions.

We compare the image quality between asymmetric wavefront codings and the simple-to-manufacture spherical aberration over an extended focal range. We verify and explain the superior performance of the spherical aberration via simulation results.

Whereas previous reported wavefront coding research has emphasised constancy of the PSF, we show that optimal image quality normally occurs for systems in which the PSF varies significantly; placing increased demands on image restoration algorithms.

Wavefront coding can mitigate the harmful effects of unwanted laser illumination. The pupil phase element spreads out the focused beam and avoids detector saturation. We consider different classes of phase masks for this application.

Estimation-theoretic limits on the extension of the depth of field of an imaging system via wavefront coding are analyzed in terms of Fisher information and associated Cramer-Rao lower bounds.

The large numerical apertures employed in millimeter wave imaging are necessary for light gathering and resolution, but result in limited depth-of-field. We explore wavefront coding to extend the depth-of-field and examine effects on system performance.

The optical transfer function of a wavefront coding odd-symmetric quadratic phase mask imager is mathematically derived. The available spatial frequency bandwidth is quantified and a special imaging condition yielding an increased dynamic range is identified.

Challenges involved in miniature camera module design and implementation will be presented. A particular camera module example will be used to show how Wavefront CodingTM technology can meet these challenges and improve overall system performance.

Wavefront Coding increases the imaging volume of application-specific imaging systems, where the goal is to optimize a specific task. As an example, we describe the design and analysis of a Wavefront Coded iris recognition system.