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The common question that is asked when acquiring a new projector for the home, office, or classroom is: would I buy an LCD projector or a DLP projector? LCD, an acronym for ‘liquid crystal device’ and DLP, which stands for ‘digital light processing’ are the two top projector imaging technologies. With so many business brands and models available, it can be confusing for the buyer to choose between both technologies. The fact is that LCD projectors offer better image quality and colour accuracy. The article below tells you why DLP projectors struggle with reproducing an equal rate of image quality.

Imagine a set of blinds in your household on your bedroom window. By twisting a rod you can turn the shutters open or closed, depending on whether you want to let light in or not. This is exactly how an LCD projector works. Each pixel functions like a unique shutter on a set of blinds to either pass light through or to block it. DLP on the other hand is created of millions of microscopic mirrors or ‘pixel elements’ as experts like to call them. Each pixel element functions to either reflect light or block it.

How the light source is processed from the point at which the projector is switched on to when the content reaches your screen is ultimately 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 different LCD panels. The 3 LCD panels make the elements of the image by processing each pixel on and off. The pixels are then simultaneously processed in a glass prism to send the projector image. Something important to remember about LCD projectors is that all three colours are directed onto your wall all at once. The way a DLP projector functions is vastly different and even the way an image shows up is not the same. With DLP, white light from the lamp is projected through a turning colour wheel with transparent red, blue and green segments, at speeds up to 11,000 rpm/s. This approach to projecting an image casts a sequence of red, blue and green light. The millions of micro mirrors described above reflect the coloured light on the pixels to construct the image elements. The elements of the image are displayed in sequence on the screen, one colour at a time. The viewer’s vision will then put together each coloured element of the image into the single whole image. In LCD projectors, all colours are available all the time to offer top brightness and spectacular colour accuracy. In DLP, just one colour is available at a time, resulting in lower colour brightness and accuracy. Some manufacturers have added a white segment into the colour wheel to improve all over brightness, but this goes and detracts from colour accuracy.

I hear in forums all the time that DLP offers a higher contrast ratio and as such must be superior quality. For those who do not 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. DLP projectors do provide high contrast specifications as compared to a majority of LCD projectors. Initially, this must be a plus, however, in truth, the true black level is determined by the ambient light in the room when the projector is being utilised. Do not be hoodwinked by contrast specifications on websites and in brochures.

When the content you plan to project has moving images, DLP projection technology can also have image errors, or ‘artifacts’. The most commonplace artifact that a DLP projector shows with moving images is colour break up. Colour break up is to be expected in DLP systems because moving images change up between the time red, blue and green colours are displayed. LCD projectors do not have this downside because every colour is sent at the same time. DLP manufacturers have created 3DLP solutions using 3 chips to fix the colour break up issue, but the price tag of these projectors make them almost impossible for the large part of businesses and consumers.

Another differentiation between LCD and DLP is how they compensate for the refractive qualities of light. Think back to high school science, and recall when they taught you how different colours of light refract various amounts when projected through the same lens. The disadvantage with DLP projectors is that they utilise the one same panel with the same lens to project Red, Blue and Green. All 3 colours are not the same and refract light in different ways. Usually with a DLP projector, some yellow colour will appear above and a spill of blue will be projected below an image as simple as a lone black line. While being built LCD projectors can be adjusted to remove these effects on the projected image, because each colour is projected on isolated LCD panels.

The one veritable benefit (excluding price) with picking a DLP projector is its smaller overall size and weight. However, this is only relevant to transport and must be traded off against the image superiority of LCD projectors. If the outcome of the picture quality is crucial to you, then the decision is no-brainer. Go for an LCD projector! LCD projectors will consistently produce bright, colourful images with fewer image errors. If you wish to learn more about LCD technology in more detail, have a look at this spectacular resource website: Explore 3LCD. If you have any further questions, visit Projector Central and send me an email.

Jonathan King is the sales and marketing manager for Projector Central, Australia’s number one online provider for projectors. Brisbane based, Projector Central has serviced Australia for 15 years. For data projectors in the Gold Coast and Interactive Whiteboards, contact Projector Central today.