Search results
Results from the WOW.Com Content Network
Yoked prism can move the image away from primary gaze without the need for a constant head tilt or turn. Prism correction is measured in prism dioptres. A prescription that specifies prism correction will also specify the "base". The base is the thickest part of the lens and is opposite from the apex.
A familiar dispersive prism An optical prism is a transparent optical element with flat, polished surfaces that are designed to refract light. At least one surface must be angled — elements with two parallel surfaces are not prisms. The most familiar type of optical prism is the triangular prism, which has a triangular base and rectangular sides. Not all optical prisms are geometric prisms ...
Prisms for near binocular disorders and for producing postural change – the use of "yoked" prisms to redirect a person's gaze and bring about a range of claimed benefits including postural improvements and increased wellbeing.
The distance in micrometers between the actual wavefront and the ideal wavefront is the wavefront aberration, which is the standard method of showing the aberrations of the eye. Therefore, aberrations of the eye are the difference between two surfaces: the ideal and the actual wavefront.
The Peli Lens is a mobility aid for people with homonymous hemianopia. It is also known as “EP” or Expansion Prism concept and was developed by Dr. Eli Peli of Schepens Eye Research Institute in 1999. It expands the visual field by 20 degrees.
The particular values depend on the prism material, the wavelength of interest as well as on the compressor parameters. Phase conjugation of chirped pulses. Chirped pulses from laser amplifiers may be phase locked via reflection from a phase-conjugating mirror to increase the brightness as .
Titanium-doped sapphire is the most common tunable solid-state laser, capable of laser operation from 670 nm to 1,100 nm wavelength. Typically these laser systems incorporate a Lyot filter into the laser cavity, which is rotated to tune the laser.
Mode locking is a technique in optics by which a laser can be made to produce pulses of light of extremely short duration, on the order of picoseconds (10 −12 s) or femtoseconds (10 −15 s). A laser operated in this way is sometimes referred to as a femtosecond laser, for example, in modern refractive surgery.
A prism compressor is an optical device used to shorten the duration of a positively chirped ultrashort laser pulse by giving different wavelength components a different time delay. It typically consists of two prisms and a mirror.
Glasses, also known as eyeglasses and spectacles, are vision eyewear with clear or tinted lenses mounted in a frame that holds them in front of a person's eyes, typically utilizing a bridge over the nose and hinged arms, known as temples or temple pieces, that rest over the ears. Glasses are typically used for vision correction, such as with ...