![]() ![]() The splitter is done by physically splicing two fibers "together" as an X.Īrrangements of mirrors or prisms used as camera attachments to photograph stereoscopic image pairs with one lens and one exposure are sometimes called "beam splitters", but that is a misnomer, as they are effectively a pair of periscopes redirecting rays of light which are already non-coincident. An optically similar system is used in reverse as a beam-combiner in three- LCD projectors, in which light from three separate monochrome LCD displays is combined into a single full-color image for projection.īeam splitters with single-mode fiber for PON networks use the single-mode behavior to split the beam. It is currently used in modern three-CCD cameras. Such a device was used in three-pickup-tube color television cameras and the three-strip Technicolor movie camera. Dichroic mirrors are used in some ellipsoidal reflector spotlights to split off unwanted infrared (heat) radiation, and as output couplers in laser construction.Ī third version of the beam splitter is a dichroic mirrored prism assembly which uses dichroic optical coatings to divide an incoming light beam into a number of spectrally distinct output beams. Depending on its characteristics, the ratio of reflection to transmission will vary as a function of the wavelength of the incident light. Instead of a metallic coating, a dichroic optical coating may be used. Later, metal was sputtered onto glass so as to form a discontinuous coating, or small areas of a continuous coating were removed by chemical or mechanical action to produce a very literally "half-silvered" surface. Originally, these were sheets of highly polished metal perforated with holes to obtain the desired ratio of reflection to transmission. To reduce loss of light due to absorption by the reflective coating, so-called " Swiss-cheese" beam-splitter mirrors have been used. A very thin half-silvered mirror used in photography is often called a pellicle mirror. The thickness of the deposit is controlled so that part (typically half) of the light, which is incident at a 45-degree angle and not absorbed by the coating or substrate material, is transmitted and the remainder is reflected. The thin coating can be aluminium deposited from aluminium vapor using a physical vapor deposition method. This is composed of an optical substrate, which is often a sheet of glass or plastic, with a partially transparent thin coating of metal. Another design is the use of a half-silvered mirror. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |