Infinity mirror

In a classic self-contained infinity mirror, a set of light bulbs, LEDs, or other point-source lights are placed around the periphery of a fully reflective mirror, and a second, partially reflective "one-way mirror" is placed a short distance in front of it, in a parallel alignment. When an outside observer looks into the surface of the partially reflective mirror, the lights appear to recede into infinity, creating the appearance of a tunnel of great depth that is lined with lights. == Explanation of effect ==

The 3D illusion mirror effect is produced whenever there are two parallel reflective surfaces which can bounce a beam of light back and forth an indefinite (theoretically infinite) number of times. The reflections appear to recede into the distance because the light actually is traversing the distance it appears to be traveling. The reflections may also appear to dim in the distance because the mirrors absorb some of the light and do not reflect all of it. For example, in a two-centimeter-thick infinity mirror, with the light sources halfway between, light from the source initially travels one centimeter. The first reflection travels one centimeter to the rear mirror and then two centimeters to, and through the front mirror, a total of three centimeters. The second reflection travels two centimeters from front mirror to back mirror, and again two centimeters from the back mirror to, and through the front mirror, totaling four centimeters, plus the first reflection (three centimeters) making the second reflection seven centimeters away from the front mirror. Each successive reflection adds four more centimeters to the total (the third reflection appears 11 centimeters deep, fourth 15 centimeters, and so on). Each additional reflection adds length to the path the light must travel before exiting the mirror and reaching the viewer. Reflection of the light also reduces the brightness of the image due to impurities in the glass. For example, most mirrors use glass with small amounts of iron oxide impurities, giving the reflection a slightly dim green tinge. Across multiple reflections, the brightness reduces further and further, and is tinted more and more green. However, mirrors used for infinity mirrors are ideally front silvered and these suffer from lower losses as the light does not travel through glass except when it finally escapes. ==Cultural references==

An early reference to an infinity mirror is found in the history of Chinese Buddhism, where the Huayan Patriarch Fazang (643–712) is said to have illustrated the "tenfold" precedent of the Huayan Jing by placing ten mirrors around a statue of the Buddha—eight mirrors in an octagon, with additional mirrors on the floor and ceiling. When he lit a torch, its light and the illuminated Buddha were reflected within reflections around the room. Visual artists, especially contemporary sculptors, have made use of infinity mirrors. Yayoi Kusama, Josiah McElheny, Ivan Navarro, Taylor Davis, Anthony James, Guillaume Lachapelle, and Hugh Hayden have all produced works that use the infinity mirror to expand the sensation of unlimited space in their artworks. The contemporary classical composer Arvo Pärt wrote his 1978 composition Spiegel im Spiegel ("mirror in the mirror") as a musical reflection on the infinity mirror effect. ==See also==