Results 31 to 40 of about 4,053 (141)
Measuring Ocular Aberrations Sequentially Using a Digital Micromirror Device
The Hartmann⁻Shack wavefront sensor is widely used to measure aberrations in both astronomy and ophthalmology. Yet, the dynamic range of the sensor is limited by cross-talk between adjacent lenslets.
Alessandra Carmichael Martins +1 more
doaj +1 more source
The use of a multichannel wavefront sensor matched with phase Zernike functions to determine the type and magnitude of aberration in the analyzed wavefront is investigated.
P.A. Khorin +2 more
doaj +1 more source
A Local Threshold Checkerboard Algorithm for Adaptive Optics System With a Plenoptic Sensor
Adaptive optics systems will encounter challenges under strong atmospheric turbulence conditions. Recently, a modified approach based on plenoptic sensor has attracted considerable attention.
Zhichong Wang +5 more
doaj +1 more source
Shack-Hartmann Wavefront Sensing of Ultrashort Optical Vortices
Light beams carrying Orbital Angular Momentum (OAM), also known as optical vortices (OV), have led to fascinating new developments in fields ranging from quantum communication to novel light–matter interaction aspects. Even though several techniques have
Alok Kumar Pandey +4 more
doaj +1 more source
A new low-cost, compact, auto-phoropter for refractive assessment in developing countries
Using a phoropter to measure the refractive error is one of the most commonly used methods by ophthalmologists and optometrists. Here, we demonstrate design and fabrication of a portable automatic phoropter with no need for patient’s feedback. The system
Babak Amirsolaimani +4 more
doaj +1 more source
The charge-coupled device-based Shaker–Hartmann wavefront sensor has been widely used to compensate for wavefront distortion in coherent optical communication.
Xu Yan +6 more
doaj +1 more source
An Optical Wavefront Sensor Based on a Double Layer Microlens Array
In order to determine light aberrations, Shack-Hartmann optical wavefront sensors make use of microlens arrays (MLA) to divide the incident light into small parts and focus them onto image planes.
Hsiang-Chun Wei +3 more
doaj +1 more source
Atmospheric turbulence causes refractive index fluctuations, which in turn introduce extra distortions to the wavefront of the propagated radiation. It ultimately degrades telescope resolution (in imaging applications) and reduces radiation power density
Ilya Galaktionov +4 more
doaj +1 more source
Adaptive Shack-Hartmann wavefront sensor accommodating large wavefront variations
Shack-Hartmann wavefront sensors (SHWFSs) usually have fixed subaperture areas on the detector, in order to fix the minimum and maximum amounts of wavefront departure, or the dynamic range of measurement. We introduce an active approach, named Adaptive Shack Hartmann Wavefront Sensor (A-SHWFS). A-SHWFS is used to reconfigure detection subaperture areas
Maham, Aftab +3 more
openaire +2 more sources
Differential wavefront curvature sensor [PDF]
In this paper, a wavefront curvature sensor is presented. This sensor is based on the measurements of the differentials of wavefront slopes, where the wavefront slope measurements can be achieved by a Shack-Hartmann sensor. A Shack-Hartmann sensor with three output collimated beams will be introduced with a lenslet array installed in each beam.
Zou, Weiyao, Rolland, Jannick
openaire +2 more sources

