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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 ...
Deformable mirrors (DM) are mirrors whose surface can be deformed, in order to achieve wavefront control and correction of optical aberrations. Deformable mirrors are used in combination with wavefront sensors and real-time control systems in adaptive optics. In 2006 they found a new use in femtosecond pulse shaping. [1]
Subsurface scattering is an indirect form of reflection where some of the light is transmitted into a semi-transparent material, scattered under the surface and bounced back out again.
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.
Because rod cells are insensitive to long wavelengths, the use of red lights and red lens glasses has become a common practice for accelerating dark adaptation. [29] In order for dark adaptation to be significantly accelerated an individual should ideally begin this practice 30 minutes prior to entering a low luminescence setting. [ 30 ]
Powerful laser guide star system at the Paranal Observatory. The actual laser guide star is the small spot above the apparent end of the laser beam. A laser guide star is an artificial star image created for use in astronomical adaptive optics systems, which are employed in large telescopes in order to correct atmospheric distortion of light (called astronomical seeing).
It consists of an array of lenses (called lenslets) of the same focal length. Each is focused onto a photon sensor (typically a CCD array or CMOS array [ 3 ] or quad-cell [ 4 ] ). If the sensor is placed at the geometric focal plane of the lenslet, [ 5 ] and is uniformly illuminated, [ 6 ] then, the integrated gradient of the wavefront across ...
Aspherics are only [citation needed] used for corrective lenses when, in order to achieve a flatter lens for cosmetic reasons, the lens design deviates from the best-form sphere; this results in degradation of the visual correction, degradation which can, in some part, be compensated for by an aspheric design. The same is true for atoric and bi ...