Search results
Results from the WOW.Com Content Network
Prism dioptres. Prism correction is commonly specified in prism dioptres, a unit of angular measurement that is loosely related to the dioptre. Prism dioptres are represented by the Greek symbol delta (Δ) in superscript. A prism of power 1 Δ would produce 1 unit of displacement for an object held 100 units from the prism. [2]
Reflex finder. A reflex finder is a viewfinder system with a mirror placed behind a lens. The light passing through the lens is reflected by the mirror to a focusing screen, usually ground glass. The image formed on this ground glass can be observed directly, giving a waist-level reflex finder, or through a redressing optical device (set of ...
A single-lens reflex camera ( SLR) is a camera that typically uses a mirror and prism system (hence "reflex" from the mirror's reflection) that permits the photographer to view through the lens and see exactly what will be captured. With twin lens reflex and rangefinder cameras, the viewed image could be significantly different from the final ...
The prism cover test ( PCT) is an objective measurement and the gold standard in measuring strabismus, i.e. ocular misalignment, or a deviation of the eye. [1] It is used by ophthalmologists and orthoptists in order to measure the vertical and horizontal deviation and includes both manifest and latent components. [1]
This category has the following 24 subcategories, out of 24 total. Canadian films by decade (15 C) Canadian films by genre (45 C) Canadian films by language (8 C) Canadian films by studio (26 C) Canadian films by topic (12 C)
Reflex camera. Cross-section view of an SLR system, one of several systems by which reflex cameras are able to operate: 1: Front-mount lens (four-element Tessar design) 2: Reflex mirror at 45-degree angle 3: Focal plane shutter 4: Film or sensor 5: Focusing screen 6: Condenser lens 7: Optical glass pentaprism (or pentamirror) 8: Eyepiece (can ...
Twin-lens reflex camera. The front of a Kinaflex twin-lens reflex camera. The focus rings of the two lenses are coupled with gears around their circumference in this simple design. A twin-lens reflex camera ( TLR) is a type of camera with two objective lenses of the same focal length. One of the lenses is the photographic objective or "taking ...
Prism (optics) 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.