projektora

Projektora is a term used in several languages to refer to the device that projects an enlarged image onto a screen or wall. In English the device is called a projector. Modern projectors use a digital imaging engine and a light source to render color images from video sources such as computers, media players, or cameras. The imaging engine modulates light and directs it through projection optics and a lens to form an image.

Technologies used in projectors include LCD, DLP, and LCOS imaging engines, sometimes with interactive input. Light sources vary from traditional lamps (such as UHP or metal halide) to LEDs and laser-based systems. Brightness is measured in lumens, resolution ranges from standard definitions up to 4K, and contrast ratio indicates the difference between bright and dark areas. Throw distance and throw ratio, along with lens options, determine how large an image will be at a given distance.

Projectors come in several form factors. Data and business projectors are common for presentations; home theater models aim to reproduce cinema-like images; short-throw and ultra-short-throw designs are suitable for small rooms; portable or pico projectors offer mobile use. Many modern devices include features such as wireless input, HDR support, built-in speakers, and in some cases interactive capabilities.

Historically, projection devices evolved from the magic lantern and slide projectors of the 19th century to film projectors of the 20th, and later to digital projectors in the late 20th century. DLP and LCD technologies became widespread in the 2000s, with laser and LED light sources becoming more common in the 2010s and beyond.

Applications for projectors span education, business presentations, cinema and home entertainment, as well as projection mapping and art installations. Important considerations include ambient light, image alignment, heat and fan noise, maintenance, and lamp or power-source life.