A Projector is a device designed to take an image from a video source and project it as faithfully as possible onto a screen or other surface. Projectors are used in a variety of different ways; they are enjoyed by home theater enthusiasts due to their ability to project movies and television programs onto a screen much larger than even the biggest TV available, and used in the corporate setting to project information onto screens large enough for rooms filled with people to see. Projectors come in a variety of different shapes and sizes and are produced by many different companies.

FUNCTIONS

A Projector is designed to receive a video signal from some external device-usually a DVD player, a Blu-Ray player, or a computer-and project that signal onto a screen. It does this by displaying the image represented in the video signal onto a small screen inside the projector itself, which is then projected onto a screen using a bright light and a lens. The lens is a piece of glass shaped in a very specific way designed to take the small image and turn it into a dramatically larger one. Projectors allow users to alter a variety of image features, including brightness, sharpness and color settings, in the same way a standard television would.

TYPES OF PROJECTOR

LCD Projectors

LCD (short for "liquid crystal display") projectors use the same techniques LCD televisions do to project their image. The projector reflects the video signal off of thousands of tiny mirrors inside the projector itself, allowing for improved clarity and resolution when the image is projected onto a screen. LCD projectors are the easiest kind to make, which in turn makes them the most affordable kind to buy.

 

DLP Projectors

DLP (short for "Digital Light Projection") projectors are coveted for their amazing image quality. They are much more expensive to produce than LCD projectors, which makes them much more expensive to buy. They employ tiny devices called "micromirrors" to display their image which leads to a perfect digitally projected image when projected onto a screen. Unlike LCD projectors, a DLP projector can display each primary color simultaneously, which leads to incredibly faithful color levels when projecting an image. Many movie theaters have started to use DLP projectors in their projection booths.

Resolution

Four different types of image resolutions (the size and quality of the projected image) are employed by projectors available on the market today. They range from a standard definition image, which is 800 by 600 pixels in size, to true high definition which is 1920 by 1080 pixels in size. The two middle-of-the-road resolutions are very similar; they are 1024 by 768 pixels in size and 1280 by 720 pixels in size. These are considered high-definition due to their marked improvement over standard-definition, but not "true" high-definition.

USES

Projectors are used in a variety of ways in a variety of different environments. In the corporate world projectors are ideal for business presentations as they allow you to display work from a computer on a screen big enough for potentially hundreds of people to see. They are also employed in schools for the same reasons.                                                             

 Home theater enthusiasts also use them as a good projector will display an image that looks better and more accurately represents the source material than most TVs on the market ever would.

HOW TO BUY A PROJECTOR

Projectors are popular and effective presentation tools for classroom and business, church and community groups and for home entertainment use. Before you buy a projector, consider the intended use and audience size and learn about the types of projectors sold. This will help you to choose a projector that is right for your application. The 2 types of projectors you will most likely consider purchasing are Liquid Crystal Display (LCD) and Digital Light Processing (DLP). 

6 FACTORS TO CONSIDER BEFORE BUYING A PROJECTOR ARE AS FOLLOWS:

1.            Determine the available space and the most common use for the projector.                                                  

This will help you narrow down the most important attributes to consider when you buy a projector.  

For example, weight will be a factor if you will transport the projector frequently. Weight will not be as important if you buy a projector for fixed installation. Portable DLP projectors are lighter than portable LCD projectors.

2.            Learn about the factors used to categorize and evaluate projectors.

                Resolution is a major factor. Projectors  used for viewing videos in a large room or auditorium, for example, will require a higher resolution than projectors used for PowerPoint presentations in an office. You need to choose a projector with a high enough resolution for its most frequent   use. A resolution of 800 x 600 DPI (dots per square inch) is generally adequate for basic PowerPoint presentations in an office or conference room. 1024 x 768 or higher allows for more detail and 1280 x 1024 for an even higher quality image.

3.            Brightness and contrast are important elements of image quality.

                Projector brightness is measured in lumens. Lumens range from 500 to 1,000 for small, dark rooms to more than 2,000 lumens for large, brightly lit rooms. Purchase a projector that is rated for the most brightly-lit uses you anticipate. Additionally, the larger your screen size, the more brightness you will need.                                                                                                         

4.            Decide how much you can spend to buy a projector.                                              

                 Projectors are available in a wide range of prices. You need to budget and balance cost and performance considerations.

                When you purchase a projector, your total purchase may also include a screen and possibly other peripherals, such as a monitor and cabling.                                                      

 5.           Determine the number and types of inputs and outputs you will require when you buy a projector.

                If you wish to project to a monitor as well as a screen, so that a speaker can refer to a      presentation without turning away from the audience, you will need to choose a projector with a second VGA or video output.

                If you plan to project video, determine whether you need to buy a projector with HDMI, composite or component video inputs.

6.            Visit a projector dealer or trade show to compare projectors.

This will help you evaluate brightness, contrast, noise level during operation and other factors that may be hard to visualize without actually seeing the projector.

                Your dealer may also have specific recommendations for your particular situation and needs