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Multifocal contact lenses (e.g. bifocals or progressives) are comparable to spectacles with bifocals or progressive lenses because they have multiple focal points. Multifocal contact lenses are typically designed for constant viewing through the center of the lens, but some designs do incorporate a shift in lens position to view through the ...
Dermatoscopy, also known as dermoscopy [1] or epiluminescence microscopy, is the examination of skin lesions with a dermatoscope. It is a tool similar to a camera to allow for inspection of skin lesions unobstructed by skin surface reflections.
In 1959, this material was first used as an optical implant. Wichterle thought pHEMA might be a suitable material for a contact lens and gained his first patent for soft contact lenses. [2] By late 1961, he succeeded in producing the first four pHEMA hydrogel contact lenses on a home-made apparatus. Copolymers of pHEMA are still widely used ...
Early embodiment of contact lens display, Canadian patent application 2280022, 1999 July 28th. A bionic contact lens is a proposed device that could provide a virtual display that could have a variety of uses from assisting the visually impaired to video gaming, as claimed by the manufacturers and developers. [1]
Afocal photography works with any system that can produce a virtual image of parallel light, for example telescopes and microscopes. Afocal photographic setups work because the imaging device's eyepiece produces collimated light and with the camera's lens focused at infinity, creating an afocal system with no net convergence or divergence in the light path between the two devices. [2]
Multifocal contact lenses (e.g. bifocals or progressives) are comparable to spectacles with bifocals or progressive lenses because they have multiple focal points. Multifocal contact lenses are typically designed for constant viewing through the center of the lens, but some designs do incorporate a shift in lens position to view through the ...
HOEs differ from other optical devices since they do not bend light with curvature and shape. Instead, they use diffraction principles (the distribution of light as it passes through an aperture) to diffract light waves by reconstructing a new wavefront using a corresponding material profile, making HOEs a type of diffraction optical element (DOE). [1]
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.