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The most common question that is asked when purchasing a new projector for the home, office, or classroom is: should 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 business brands and types available, it can be confusing for the buyer to pick between those technologies. The fact is that LCD projectors provide far superior image quality and colour accuracy. The article below tells you why DLP projectors struggle with projecting a similar grade of image quality.

It’s like a set of blinds in your household covering your bedroom window. With the twist of a rod you can make the shutters open or closed, depending on whether you want to let light in or not. And this is exactly how an LCD projector functions. Each pixel works like its own shutter on a set of blinds to either send light through or to block it. DLP on the other hand is made up of millions of microscopic mirrors or ‘pixel elements’ as the experts like to call them. Each pixel element works to either reflect light or block it.

How the light source is processed from the point when the projector is turned on to when the content reaches your screen is absolutely significant in regard to image quality, brightness and colour accuracy. LCD projectors process white light from the lamp by separating 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 create the elements of the image by shining each pixel on and off. The pixels are then projected in a glass prism to create the projector image. An important point to know about LCD projectors is that all three colours are delivered onto your screen all at the same time. The way a DLP projector works is totally different and even how an image appears is not the same. With DLP, white light from the lamp is processed through a rotating colour wheel with transparent red, blue and green segments, at speeds up to 11,000 rpm/s. This way of making an image forms a sequence of red, blue and green light. The millions of micro mirrors as mentioned above reflect the coloured light on the pixels to form the image elements. The elements of the image are projected in sequence on the screen, one colour at a time. The viewer’s eyes will then draw each coloured element of the image into the single whole image. From LCD projectors, all colours are available all the time to create high brightness and fantastic colour accuracy. In DLP, only one colour is available at a time, resulting in lower colour brightness and accuracy. Some DLP designers have included a white segment into the colour wheel to improve general brightness, but this further damages colour accuracy.

I find in forums all the time that DLP has a higher contrast ratio and therefore must be better. For those who are uncertain, 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 machine is capable of producing. DLP projectors do have high contrast specifications as compared to the majority of LCD projectors. At first glance, this appears to be a plus, however, in truth, the true black level is determined by the ambient light in the room while the projector is utilised. Do not be tricked by contrast specifications on websites and in brochures.

When the content you wish to bring to life includes moving images, DLP projection technology also has image imperfections, or ‘artifacts’. The most common 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 between the time red, blue and green colours are displayed. LCD projectors do not have this downside because all colours are processed at once. DLP builders have come up with 3DLP solutions using 3 chips to answer the colour break up error, but the cost of these projectors make them impractical for the large part of businesses and consumers.

Another difference between LCD and DLP is how they balance for the refractive qualities of light. Jump back to high school science, and recall how the various colours of light refract different amounts when directed through the same lens. The problem with DLP projectors is that they have the one same panel for the same lens to project Red, Blue and Green. All 3 colours are obviously different and refract light in different ways. Usually with a DLP projector, some yellow colour will come up above and some extra blue will appear below an image as simple as a single black line. While being built LCD projectors can be set to minimize these effects on the projected image, as each colour is projected on isolated LCD panels.

The isolated veritable buy point (excluding price) with deciding on a DLP projector is its overall smaller size and weight. However, this is only relevant for mobility and cannot be traded off against the image benefits of LCD projectors. If the outcome of the picture quality is vital to you, then the decision is simple. Go for an LCD projector! LCD projectors will consistently make bright, colourful images with fewer image errors. If you desire to ask more about LCD technology in more detail, have a gander at this tremendous resource website: Explore 3LCD. If you have any persisting questions, go to Projector Central and send me an email.

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