The most typical question heard when looking for a new projector for the home, office, or classroom is: will I get an LCD projector or a DLP projector? LCD, an acronym for ‘liquid crystal device’ and DLP, short for ‘digital light processing’ are the two most common projector imaging technologies. With so many different brands and different types available, it can be overwhelming for consumers to make a choice between these technologies. It comes down to the fact that LCD projectors offer superior image quality and colour accuracy. The next paragraph will tell you why DLP projectors struggle with reproducing a comparable level of image quality.

It’s like a set of blinds in your home on your bedroom window. By pulling a rod you can turn the shutters open or closed, depending on whether you want to let light in or not. And that is exactly how an LCD projector behaves. Each pixel operates like its own shutter on a set of blinds to either pass light through or to block it. DLP on the other hand is made up of millions of microscopic mirrors or ‘pixel elements’ as professionals like to call them. Each pixel element functions to either reflect light or block it.

How the light source is processed from the time the projector is switched on to when the content reaches your screen is absolutely significant to image quality, brightness and colour accuracy. LCD projectors project white light from the lamp by splitting it into red, blue and green components, by three mirrors which direct the coloured light to 3 stand alone LCD panels. The 3 LCD panels form the elements of the image by switching each pixel on and off. The pixels are then combined in a glass prism to send the projector image. Something to understad about LCD projectors is that all three colours are sent onto your wall at the same time. The way a DLP projector operates is widely different and even the way an image appears is not the same. With DLP, white light from the lamp is sent through a rotating colour wheel with transparent red, blue and green segments, at speeds up to 11,000 rpm/s. This method of creating an image forms a sequence of red, blue and green light. The millions of micro mirrors described above reflect the coloured light on the pixels to create the image elements. The elements of the image are sent in sequence on the screen, one colour at a time. The viewer’s eye will then draw each coloured element of the image into the full image. With LCD projectors, all colours are available all the time to deliver the best brightness and great colour accuracy. In DLP, just one colour is available at once, and so causing lower colour brightness and accuracy. Some developers have included a white segment for the colour wheel to improve overall brightness, but this then damages colour accuracy.

I hear in forums all the time that DLP offers a higher contrast ratio and thus must be superior quality. For those who don’t know, the contrast ratio is a measure of a display system defined as the ratio of the luminance of the brightest white to that of the darkest black that the system is capable of producing. DLP projectors do have high contrast specifications in comparison to a majority of LCD projectors. At first glance, this appears to be a benefit, however, in reality, the true black level is determined by the ambient light in the room while the projector is being utilised. Do not be duped by contrast specifications on websites and in brochures.

When the content you are trying to project has moving images, DLP projection technology also has image imperfections, or ‘artifacts’. The most commonplace artifact that a DLP projector forms with moving images is colour break up. Colour break up is unavoidable in DLP systems because moving images change between the time red, blue and green colours are pulled up. LCD projectors do not have this problem because every colour is sent simultaneously. DLP developers have come up with 3DLP solutions using 3 chips to resolve the colour break up problem, but the cost of these projectors make them hardly practical for most businesses and consumers.

Another differentiation between LCD and DLP is how they balance for the refractive qualities of light. Think back to high school science, and remember how different colours of light refract different amounts when directed through the same lens. The downside with DLP projectors is that they use the one same panel and the same lens to project Red, Blue and Green. All 3 colours are different and refract light in a different way. Generally with a DLP projector, some yellow colour will come up above and a superfluous blue will come up below an image of something as simple as a lone black line. In manufacturing LCD projectors can be adapted to take away these effects on the projected image, because each colour is refracted on isolated LCD panels.

The only veritable plus (excluding price) with taking a DLP projector is its smaller size and weight. However, this is only relevant in regard to transporting the device and must be traded off against the image advantages of LCD projectors. If the result of the picture quality is crucial to you, then the answer is a no-brainer. Choose an LCD projector! LCD projectors will constantly show bright, colourful images with fewer image mistakes. If you wish to find out more about LCD technology in more detail, have a gander at this fabulous resource website: Explore 3LCD. If you have any additional questions, visit Projector Central and send me an email.

Jonathan King is the sales and marketing manager for Projector Central, Australia’s top online shop for projectors. Brisbane based, Projector Central has been servicing Australia for 15 years. For data projectors in Brisbane and Interactive Whiteboards, contact Projector Central today.