Screen Projectors

Screen projectors
Types of screen projectors high-resolution screen projectors screen projectors
Screen projectors
Types of screen projectors
high-resolution screen projectors

screen projectors



Screen Projectors: A Brief Buyer's Guide

If you're thinking about buying a screen-projector-based home TV system, you have a lot choices. Screen projectors come in several versions and have a bewildering range of features and technical data. This article presents some basic information about screen projectors to assist you in making an informed buying decision.

First, here's an overview of what types of screen projectors are available. In general, screen projectors interpret the video signal and magnify it. The image is enlarged and projected onto a viewing screen using a system of lenses. There are two types of projectors: front and rear. Front projectors are separate items from the TV itself while rear projectors are often built right into to TV cabinet.

There are 3 varieties of screen projectors: CRT, DLP and LCD.

CRT stands for cathode ray tube. CRT screen projectors have 3 beams, one for each primary color (red, blue, green). A magnifying glass enlarges the images before sending them to the screen. CRTs have superior black levels and fleshtones compared to other screen projectors technology. Although large and heavy, CRTs have long tube life, no pixelation and deliver excellent image quality. These types of screen projectors deliver rich colors with good contrast. Disadvantages of CRT screen projectors include the fact that tubes are expensive to replace. CRTs also are not a bright as other types of screen projectors and older models need to readjusted occasionally. CRTs are expensive and can cost $10,000 or more. If you're looking for a cost-effective plug-and-play type projector, a CRT probably isn't for you.

The most popular screen projectors for home applications are DLPs. DLP stands for digital light projector. DLP projectors use micromirrors to generate an image. Light reflects off the micromirrors that pass light through a rotating color wheel. DLPs are small and light and easy to set up - they're more plug-and-play than CRTs. While CRTs can drift out of alignment, DLPs remain stable. Maintenance (changing the bulb) is simple and straightforward. While capable of high resolution, you may notice a rainbow effect on a DLP if you move your eyes quickly back and forth. Some people claim that this effect causes them headaches. Contrast and color are good on DLPs and newer models have better brightness than CRT screen projectors. On the down side, DLPs bulbs are expensive ($300-$500), have a relatively short life (1000-2000 hours) and are hard to find for older models. Also, you might notice some pixelation, poor black level and poor fleshtones.

LCD stands for liquid crystal display. LCD screen projectors are similar to DLPs in that they utilize a light reflecting technology. This technology manipulates polarized light to produce an image by creating a pixel array by using a thin layer of liquid crystal sandwiched between two specially treated glass plates. This technology produces millions of colors. LCD projectors are somewhat similar to DLP projectors. The color image is displayed on a transparent chip made up of pixels. Light passes through the chip to project the image on the screen. Capable of high resolution, LCD projectors offer color accuracy that's enhanced by good contrast. LCDs are small and light and simple to set up (plug-and-play). They offer less pixelation than CRTs and display good fleshtones. Finally, it's easy to change bulbs. One drawback is that pixels may be visible when the LCD projects images on a large screen.

In addition to the three types of screen projectors mentioned above, there is a fourth type, plasma, also known as PDP (which stands for plasma display panel). Plasma TV works similar to a fluorescent light bulb in that the image is produced by electrically exciting gases trapped between 2 glass panels. The excited gases transform into a plasma, which in turn excites phosphors in the tube to emit light and form the image.

Regardless of which technology you choose, you should also consider a couple of other issues:

Throw distance and display size. The throw distance is the distance between the projector and the screen. Screen projectors' throw distances are highly variable, so be sure to verify this before finalizing your purchase. Measure the room where you plan to use the TV to confirm that it will accommodate the TV's throw distance. Display size is another important feature that also depends on room size. Make sure that the minimum display size isn't too big for the room.




screen projectors
Screen projectors Types of screen projectors high-resolution screen projectors
screen projectors