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Adaptive optics (AO) is a technique of precisely deforming a mirror in order to compensate for light distortion. It is used in astronomical telescopes [ 1 ] and laser communication systems to remove the effects of atmospheric distortion , in microscopy, [ 2 ] optical fabrication [ 3 ] and in retinal imaging systems [ 4 ] to reduce optical ...
The illumination models listed here attempt to model the perceived brightness of a surface or a component of the brightness in a way that looks realistic. Some take physical aspects into consideration, like for example the Fresnel equations, microfacets, the rendering equation and subsurface scattering.
In adaptive optics, the Greenwood frequency [1] is the frequency or bandwidth required for optimal correction with an adaptive optics system. It depends on the transverse wind speed and the turbulence strength in the atmosphere.
Adjustable focus lenses, like single-focus lenses, also reduce image-jump and spatial distortion in the field of view associated with traditional multi-focal lenses. Additionally, the ideal near-vision correction can be achieved with precision, because the variable lenses emulate the focusing action of the youthful (non-presbyopic) eye.
where V 1 and V 2 are the Abbe numbers of the materials of the first and second lenses, respectively. Since Abbe numbers are positive, one of the focal lengths must be negative, i.e., a diverging lens, for the condition to be met. The overall focal length of the doublet f is given by the standard formula for thin lenses in contact:
Vertex distance is the distance between the back surface of a corrective lens, i.e. glasses (spectacles) or contact lenses, and the front of the cornea. Increasing or decreasing the vertex distance changes the optical properties of the system, by moving the focal point forward or backward, effectively changing the power of the lens relative to ...
Optical lens design is the process of designing a lens to meet a set of performance requirements and constraints, including cost and manufacturing limitations. Parameters include surface profile types (spherical, aspheric, holographic, diffractive, etc.), as well as radius of curvature, distance to the next surface, material type and optionally tilt and decenter.
The concept of red lenses for dark adaptation is based upon experimentation by Antoine Béclère and his early work with radiology. In 1916, the scientist Wilhelm Trendelenburg invented the first pair of red adaptation goggles for radiologists to adapt their eyes to view screens during fluoroscopic procedures.