Laser sensing has been applied in various underwater applications, ranging from underwater detection to laser underwater communications. However, there are several great challenges when profiling underwater turbulence effects. Underwater detection is greatly affected by the turbulence effect, where the acquired image suffers excessive noise, blurring, and deformation. In this paper, we propose ...

We introduce a Shack-Hartmann wavefront sensor for adaptive optics that enables dynamic control of the spatial sampling of an incoming wavefront using a segmented mirror microelectrical mechanical systems (MEMS) device. Unlike a conventional lenslet array, subapertures are defined by either segments or groups of segments of a mirror array, with the ability to change spatial pupil sampling arbit...

Interferometric techniques are attractive in wavefront sensing because they give a direct measure of the phase (as opposed to the first or second derivative) which means they are useful for use with a piston-only wavefront corrector (such as a liquid crystal spatial light modulator, or some MEMS mirrors). In this paper we describe (also described in ref 1) a novel method of implementing a commo...

We present a new method to directly measure and correct the aberrations introduced when imaging through thick biological tissue. A Shack-Hartmann wavefront sensor is used to directly measure the wavefront error induced by a Drosophila embryo. The wavefront measurements are taken by seeding the embryo with fluorescent microspheres used as "artificial guide-stars." The wavefront error is correcte...

Compact numerical schemes provide high-order solution of PDEs with low dissipation and dispersion. Computer implementation of these schemes requires numerous passes of data through cache memory that considerably reduces performance of these schemes. To reduce this di culty, a novel algorithm is proposed here. This algorithm is based on a wavefront approach and sweeps through cache only twice.

The aberration field of an optical system with a tilted pupil is explored through expanding the vector expressions of the third-order wavefront aberrations. First, the vector forms of the wavefront aberrations are modified to obtain the aberration expressions with the pupil tilted; full field displays of coma and astigmatism in this situation are given. Then, the third-order aberration formulas...

The central problem in Adaptive Optics feedback control is the reconstruction of the aberrated wavefront from wavefront sensor measurements. We recently presented a novel algorithm to compute the wavefront estimate directly from (Shack-)Hartmann intensity images instead of using the classical centroid algorithm to approximate the local wavefront slopes. The novel algorithm allows a distributed ...

PURPOSE To analyze the ocular wavefront aberrations in patients with facial dystonia treated with botulinum toxin A. METHODS Patients with benign essential blepharospasm and hemifacial spasm in activity underwent slit lamp examination and bilateral wavefront analysis under pharmacologic mydriasis using Alcon LADARvision wavefront aberrometry system. After that, all patients were treated with ...

Diffractive optical elements suffer from large chromatic aberration due to the strong wavelength-dependent nature in diffraction phenomena, and therefore, diffractive elements can work only at a single designed wavelength, which significantly limits the applications of diffractive elements in imaging. Here, we report on a demonstration of a wavefront coded broadband achromatic imaging with diff...