Search results
Results From The WOW.Com Content Network
Before and after those years, vehicles could have model-specific, nonstandard-shape headlamps, using any of a wide variety of replaceable light bulbs. Between 1940 and 1956, all U.S. cars had to have two 7-inch (178 mm) round headlamps with dual filaments, so each lamp provided both a high and a low beam light distribution.
Compared to the Leupold mount, the Weaver rail is not as strong and cannot be adjusted for windage. [ 4 ] W.R. Weaver Co. became Weaver Optics, and was a subsidiary of Meade Instruments Corporation from 2002 to 2008, when it was on-sold to become part of Alliant Techsystems 's Security and Sporting division in Onalaska, Wisconsin.
A light fixture (US English), light fitting (UK English), or luminaire is an electrical lighting device containing one or more light sources, such as lamps, and all the accessory components required for its operation to provide illumination to the environment. [1] All light fixtures have a fixture body and one or more lamps.
A large German equatorial mount on the Forststernwarte Jena 50cm Cassegrain reflector telescope. An equatorial mount is a mount for instruments that compensates for Earth's rotation by having one rotational axis, called polar axis, parallel to the Earth's axis of rotation. [1] [2] This type of mount is used for astronomical telescopes and cameras.
A bayonet mount A bayonet mount before and after insertion Early-19th century socket bayonet Socket of a bayonet. A bayonet mount (mainly as a method of mechanical attachment, such as fitting a lens to a camera using a matching lens mount) or bayonet connector (for electrical use) is a fastening mechanism consisting of a cylindrical male side with one or more radial pegs, and a female receptor ...
For the simplified scenario of visible light travelling from air (n 0 ≈ 1.0) into common glass (n S ≈ 1.5), the value of R is 0.04, or 4%, on a single reflection. So at most 96% of the light (T = 1 − R = 0.96) actually enters the glass, and the rest is reflected from the surface. The amount of light reflected is known as the reflection loss.
Battlefield illumination is technology that improves visibility for military forces operating in difficult low-light conditions. The risks and dangers to armies fighting in poor light have been known since Ancient Chinese times. [1] Prior to the advent of the electrical age, fire was used to improve visibility on the battlefield.
An arc lamp or arc light is a lamp that produces light by an electric arc (also called a voltaic arc). The carbon arc light, which consists of an arc between carbon electrodes in air, invented by Humphry Davy in the first decade of the 1800s, was the first practical electric light .