optyka: Risley prisms

Evidence: 100 • authority: 72

Risley prisms (also called a Risley prism pair or rotating wedge prisms) are a beam steering device comprising two thin wedge prisms mounted coaxially and rotated independently about the optical axis. By varying the relative rotation angles of the wedges, the device deflects an incident beam to any azimuth within a cone whose half-angle is set by the prism wedge angles and glass refractive index. Risley pairs are used for beam steering and pointing in applications such as free-space laser communications, tracking, scanning and imaging lidar, and in ophthalmic instruments for variable prism testing of ocular alignment. Advantages include a compact, sealed, and coaxial form factor; continuous…

Evidence: 36 • authority: 80

Proton Form Factor Puzzle and the CEBAF Large Acceptance Spectrometer(CLAS) Two-Photon Exchange Experiment

Evidence: 36 • authority: 80

High-Precision Calibration Algorithm for Pointing Accuracy of a Two-Axis Rotary Table and Precision Tracking Camera

Evidence: 36 • authority: 88

Modeling of compliant-based support for large aperture rotary prisms with horizontal-axis. In the Thirty-Meter-Telescope (TMT), a pair of wedge prisms with diameters of approximately 1500 mm are proposed to mitigate atmospheric dispersion across different zenith angles. This is achieved through controlled linear and rotary movements of the prisms. However, providing stable support for such large aperture prisms, with variable cross-sections and capable of rotating 360° around a horizontal optical axis, poses a significant challenge. This paper introduces a compliant-based support method tailored for TMT’s large aperture prisms. The methodology involves a mechanical analysis of the wedge pri…