A video projector is a projector, which receives a video signal and projects the corresponding image on a projection screen using a lens system. All LCD projectors and DLP projectors use a very bright light to project the image can.
The function and use of projectors.
projectors are widely used for many applications such as conference room presentations, classroom, home theater and concerts. Projectors are used in many schools and other educational institutions and are sometimes connected to an interactive "whiteboard" to teach students interactively. A video projector, which is also known as a digital projector, projected on a traditional reflective projection screen . He can also be built into a cabinet with a translucent rear-projection screen to form a unified display device can . Most display resolutions of Contemporary Beamer are : SVGA (800 × 600 pixels), XGA (1024 × 768 pixels), 720p (1280 × 720 pixels), and 1080p (1920 × 1080 pixels). The cost of a device are determined not only by its potential resolution, but also by its light output. A projector with a lower light output (measured in lumens , "lm" ) requires a smaller screen and a room with a smaller amount of ambient light. For example, a light output of about 1,500 to 2,500 ANSI lumens is more suitable for small screens in rooms with low ambient light. Around 2500-4000 lm is suitable for medium-sized screens with an average amount of ambient light. Projectors over 4000 lm suitable for very large screens or for use in rooms without light control, such as in conference rooms. Some camcorders even have a small built-in projector. Also, there are still many portable projectors, such as the so-called "pico projectors" in your pocket.
Different types of projectors
With a growing Do-it-yourself (DIY) community and an increasing interest in low-cost devices have some developers strives to provide their own projectors with kits and source components or to build them from scratch. Currently there is a growing trend in the field of projectors, whether for domestic use or for use in the classroom. The most common types of projectors are: CRT projectors with cathode ray tubes; LCD projector with LCD light gates; DLP projectors with Texas Instruments DLP technology; LCOS projectors with liquid crystal on silicon
overview of the upcoming used techniques.
LCD projectors are very color-rich projector, graphics and texts in very good visibility map due to the clear separation of individual pixels. Here come transparent active matrix liquid crystal displays used. These projectors are usually very handy and have a low weight.
DLP projectors operate at a high speed because there tiny mirror (Digital Micromirror Device DMD short) can be used for projection. This technique has been developed by Texas Instruments. One advantage of DLP projectors is about 5 times longer life than the LCD projectors
LED projectors use as the name suggests as a light source LED's ( Light Emitting Diode ) is a. Since LED's have to use less energy, these projectors are less cooled and can be equipped with quieter fans. These fans are also space-efficient, making it possible to distribute these projectors in smaller enclosures. These can also be operated by the lower energy consumption with a battery. In addition, the coming to the use of LED's hold more than 20,000 hours.
Technical aspects of the different projectors are light intensity ( this is stated in lumens and is usually 1000-4500 lm), the projection ratio or the volume and noise.
Known projector manufacturers are Hitachi, Panasonic, Philips , Epson and NEC
little note at the end:.
the word viewer comes from Latin of "proicere" from and is composed of the prefix and the verb per iacere together. Iacere in translation means "throw" and the prefix pro with can be translated "before". An interpretation of the meaning is forward throw about. So an image on a surface "throw".