The Polylux was an overhead projector produced in the German Democratic Republic (GDR). It also functioned as a generic name for overhead projectors in the GDR.
The Polylux was produced in the VEB (Volkseigener Betrieb: people’s enterprise) Phylatex-Physikgeräte DDR, in Frankenberg near Chemnitz (then known as Karl-Marx-Stadt). It was, amongst others, widespread in educational institutions in the GDR. After 2004, Polylux was a registered trademark of the company Polytechnik Frankenberg GmbH, which as a successor firm of the original Polylux producer continued to produce the device. Until the Wende in 1989, 27,000 devices were produced on average each year, and were also exported to the Soviet Union. In the year 2004, 6,000 devices were still being produced.
In 2006, the enterprise closed down.
The word Polylux (from Greek and Latin, meaning "much light") originates with Erich Schöpe, a physicist and former director of the Polylux manufacturer. Today, the word enjoys cult status as a typical GDR word and is still widespread in everyday language of the East German states.
A television show produced by Ostdeutscher Rundfunk Brandenburg (now Rundfunk Berlin-Brandenburg) was named after the Polylux with reference to the "enlightening" function of the device.
The body of the Polylux consisted of plastic and contained a ventilator with delayed shutdown in order to avoid a heat build-up. The light source was a halogen light bulb for a standard line voltage. It contained a switch for two different light intensity levels.
Originally, the lenses of the device were made out of glass. In order to reduce the weight, lenses made of plastic were later used. In particular, the Fresnel lens with its large surface area, on which transparencies were placed, was made out of plastic.
A planetarium is a theatre built primarily for presenting educational and entertaining shows about astronomy and the night sky, or for training in celestial navigation.
A Fresnel lens is a type of composite compact lens which reduces the amount of material required compared to a conventional lens by dividing the lens into a set of concentric annular sections.
A slide projector is an opto-mechanical device for showing photographic slides.
An overhead projector, like a film or slide projector, uses light to project an enlarged image on a screen, allowing the view of a small document or picture to be shared with a large audience.
An LCD projector is a type of video projector for displaying video, images or computer data on a screen or other flat surface. It is a modern equivalent of the slide projector or overhead projector. To display images, LCD projectors typically send light from a metal-halide lamp through a prism or series of dichroic filters that separates light to three polysilicon panels – one each for the red, green and blue components of the video signal. As polarized light passes through the panels, individual pixels can be opened to allow light to pass or closed to block the light. The combination of open and closed pixels can produce a wide range of colors and shades in the projected image.
A marker pen, fine liner, marking pen, felt-tip pen, felt pen, flowmarker, sign pen, vivid, flomaster, texta, sketch pen, koki or simply marker is a pen which has its own ink source and a tip made of porous, pressed fibers such as felt. A marker pen consists of a container and a core of an absorbent material that holds the ink. The upper part of the marker contains the nib that was made in earlier times of a hard felt material, and a cap to prevent the marker from drying out.
ARD is a joint organisation of Germany's regional public-service broadcasters. It was founded in 1950 in West Germany to represent the common interests of the new, decentralised, post-war broadcasting services – in particular the introduction of a joint television network.
A movie projector is an opto-mechanical device for displaying motion picture film by projecting it onto a screen. Most of the optical and mechanical elements, except for the illumination and sound devices, are present in movie cameras. Modern movie projectors are specially built video projectors.
The opaque projector, or episcope is a device which displays opaque materials by shining a bright lamp onto the object from above. The episcope must be distinguished from the diascope, which is a projector used for projecting images of transparent objects, and from the epidiascope, which is capable of projecting images of both opaque and transparent objects.
A carousel slide projector is a slide projector that uses a rotary tray to store slides, used to project slide photographs and to create slideshows. It was first patented on May 11, 1965, by David E. Hansen of Fairport, New York. Hansen was an industrial designer at the Eastman Kodak Company. A patent for the rotary tray was granted in 1966 after a 1962 application by the Eastman Kodak Company.
VEB Polytechnik was a company from the German Democratic Republic (GDR) located in Chemnitz. In the GDR, it was mainly known for producing overhead projectors, called Polylux.
A gobo is an object placed inside or in front of a light source to control the shape of the emitted light and its shadow.
A stepper is a device used in the manufacture of integrated circuits (ICs) that is similar in operation to a slide projector or a photographic enlarger. Stepper is short for step-and-repeat camera. Steppers are an essential part of the complex process, called photolithography, which creates millions of microscopic circuit elements on the surface of silicon wafers out of which chips are made. These chips form the heart of ICs such as computer processors, memory chips, and many other devices.
Radio DDR 1 was a radio channel produced and transmitted by Rundfunk der DDR, the radio broadcasting organization of East Germany (GDR). It had a mixed of news and light entertainment schedule, with an emphasis on events in the GDR, and also included regional programming.
Deutschlandsender, abbreviated DLS or DS, was one of the longest-established radio broadcasting stations in Germany. The name was used between 1926 and 1993 to denote a number of powerful stations designed to achieve all-Germany coverage.
Ostdeutscher Rundfunk Brandenburg, based in Potsdam, was the public broadcaster for the German federal state of Brandenburg from 12 October 1991 until 30 April 2003. It was a member organization of the consortium of public-law broadcasting organizations in Germany, ARD.
Document cameras, also known as visual presenters, visualizers, digital overheads, or docucams, are real-time image capture devices for displaying an object to a large audience. Like an opaque projector, a document camera is able to magnify and project the images of actual, three-dimensional objects, as well as transparencies. They are, in essence, high resolution web cams, mounted on arms so as to facilitate their placement over a page. This allows a teacher, lecturer or presenter to write on a sheet of paper or to display a two or three-dimensional object while the audience watches. Theoretically, all objects can be displayed by a document camera. Most objects are simply placed under the camera. The camera takes the picture which in turn produces a live picture using a projector or monitor. Different types of document camera/visualizer allow great flexibility in terms of placement of objects. Larger objects, for example, can simply be placed in front of the camera and the camera rotated as necessary, or a ceiling mounted document camera can also be used to allow a larger working area to be used.
Deutscher Fernsehfunk was the state television broadcaster in the German Democratic Republic from 1952 to 1991.
The design of photographic lenses for use in still or cine cameras is intended to produce a lens that yields the most acceptable rendition of the subject being photographed within a range of constraints that include cost, weight and materials. For many other optical devices such as telescopes, microscopes and theodolites where the visual image is observed but often not recorded the design can often be significantly simpler than is the case in a camera where every image is captured on film or image sensor and can be subject to detailed scrutiny at a later stage. Photographic lenses also include those used in enlargers and projectors.
A projector or image projector is an optical device that projects an image onto a surface, commonly a projection screen. Most projectors create an image by shining a light through a small transparent lens, but some newer types of projectors can project the image directly, by using lasers. A virtual retinal display, or retinal projector, is a projector that projects an image directly on the retina instead of using an external projection screen.