What are the basic functions or features that one should be looking out for when purchasing a projector? The following is a simple guide on what to look for and how these functions fit into your requirement.

Brightness
This is probably one of the most important features that most, if not all, buyers consider when looking for a projector.

Brightness of a projector is usually presented in ANSI Lumens (acronym of ANSI is the American National Standards Institute, who developed the method in measuring projected brightness) however not all brands adopt this standard. Due to the varying standards of measuring brightness in the market, you should be aware that two projectors with the same quoted brightness might not necessarily give you the same amount of brightness.

In general, a higher brightness projector is able to produce a better and clearer image, but it really depends on your requirement. A projector that is too bright for, say a small room, may be over-kill and will cause discomfort to the eyes.

Determine the brightness of your projector depends mainly on 3 factors:

• Screen Size
• Ambient Light (Surrounding lighting condition)
• Type of projected contents

A larger screen size will require a projector to be placed further away from the screen which translate to a bigger amount of light loss while travelling across a longer distance, hence a higher brightness projector is required to produce a clear image.

Ambient light includes electrical lighting, sunlight, lighting from other nearby light emitting devices etc. With the presence of excessive ambient light, it will result in more light reflecting off the projected screen and hence ‘dimming’ the brightness of the actual projection.

If regular projection of small, fine details and sharp images are necessary, you will need a higher brightness projector as compared to projecting images with large bulky fonts.

Projection System
There are a handful of projection systems in the market namely the common ones are:

• 3LCD – 3 Chip Liquid Crystal Display
• 1-Chip DLP – 1 Chip Digital Light Processing
• 3-Chip DLP – 3 Chip Digital Light Processing
• LCoS – Liquid Crystal on Silicon
• QuaDrive

The common ones you will see are probably 3LCD, 1-Chip DLP and LCoS. 3-Chip DLP are mainly for higher end Home Theatre or Cinema projectors while QuaDrive system is an optical engine improvement from 3LCD system by Sanyo, which by itself command a heftier price tag.

Without confusing you with the technical differences of the various systems, I suppose the more critical questions are “how does each of the system perform differently from each other and their difference in price?” I shall give a brief review on how I view each of the 3 more common systems for data projector.

3LCD

The key advantage of a 3LCD Projection System lies in the fact that most, if not all, monitors in the market uses the same LCD technology. This translates to 3LCD projectors having the capabilities of reproducing the same color you would see on your LCD screen.

Due to the nature of how a 3LCD system operates, it is also capable of producing an unparallel grayscale range, giving the projected image greater variation in shadow, depth and details.

Utilizing 3 sets of dedicated primary colored LCD chips to process white light emitted from the lamp; it maximizes the light efficiency, which translate to better energy savings.

1-Chip DLP

A DLP projector uses a combination of a DMD chip and a rotating Color Wheel to digitally process a projected image. This system not only enables a 1-Chip DLP projector in achieving excellent black and white control, it also create vivid true to life colored images.

Further developments in the design of the color wheel help enhance the color performance of the projected image, a technology they call “BrilliantColor”. Instead of using the conventional 4-segments color wheel, a maximum of 6 segments are used to further enhance the color and visual experience.

Sequential color reproduction nature of the 1-Chip DLP system requires our brain to manually piece the fast moving single colored images into a full colored one. This method of projection may have induced some to dispute the discomfort caused on ones eye during prolong viewing, but the 1-Chip DLP system makes it up by its capabilities in producing sharp and clear images, in particular on thin font characters, which inversely make viewing easier.

LCoS

Many have described an LCoS projection system as a hybrid between a 3LCD and DLP. It harnesses the benefits of both systems to achieve a smooth and high-resolution image.

LCoS may not be in the category of mass-market demand projector like the 3LCD or DLP, but it does not put it any inferior to them. One of the most prominent advantages of the LCoS system is having a less prominent pixel structure thus generating extremely smooth and natural images. Adopting the same 3-chip dedicated color-processing system like a 3LCD, ability to reproduce color is also amongst the top performers.

Having said the above, traditionally LCoS projectors does demand a heftier price tag, which could be the main reason it was not quite in the same league as the 3LCD & 1-Chip DLP Projectors.

Summary:

After a very brief run through of the 3 common projection systems, you have probably identified that each system has its advantages. To sum things off, regardless of each system advantage over others, the quality of a projected image is still subjective to individual’s preference.

Below are some white papers and reviews archived from reputable sites should you be keen to read in-depth comparison of the technologies.

http://www.projectorcentral.com/lcd_dlp.htm

http://www.projectorcentral.com/lcd_dlp_comparison.htm

http://www.projectors.co.uk/sitepage/Projector%20Technology.html