Digital projectors are equipments of modern technology. These are used to convert image data directly from the computer onto a screen via lens system. Digital projectors provide visualization of data that is actually stored in a computer for presentation. These projectors enable the viewers to watch moving images from a DVD, digital versatile disc player. Advertisers or sellers also use these projectors to give demonstration of products to a large number of customers. It can easily convert written documents onto an interactive whiteboard.
Digital projectors play an important role in the formation of home theater systems. These projectors use resolution of SVGA standard i.e. 800×600 pixels in expensive devices. Cost of digital projector is determined by its resolution as well as its brightness. If you’re going to use it in large rooms or big conference halls its brightness should be from 1,000 to 4,000 ANSI lumens.
First digital projectors, Eidophor projectors were introduced in 1950. Eidopher projectors used an oily surface in a rotating disk with light shining through it and employed an electron beam to disrupt oil in a specific manner. Eidophor projectors were not able to produce colors. Nowadays there are several high quality models of digital projectors are available in market so Eidopher projectors are less common.
Following four technologies are used in digital projectors:
High intensity CRT
LCD projectors using LCD light gates
Texas Instruments' DLP technology
Eidophor oil-film projectors (obsolete)
At present LCD projectors use Texas Instruments’ DLP technology whereas the high intensity CRT devices are suitable for enduring installations. Entire working of cathode ray tube digital projectors is like CRT television set. These projectors may be configured with one RGB color tube that has three colors red, green and blue with a single lens, one black & white tube with a rotating color wheel or three RGB color tubes with three lenses.
Projectors having cathode ray tubes are usually bulky thats why these are the best projectors for fixed installations.
LCD digital projectors are portable and lighter enough in comparison to CRT and can be easily shifted from one place to another. These are very much popular and available in various shapes and sizes. CRT and LCD digital projectors come under the category of transitive projectors.
Reflective projectors are the superior digital projectors that provide high quality images. These are affordable and offer next level of entertainment. Everyone can enjoy home theater applications with the help of digital projectors.