The most typical question asked when purchasing 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 popular projector imaging technologies. With so many business brands and different models available, it can be challenging for consumers to make a choice between these technologies. Ultimately LCD projectors give better image quality and colour accuracy. The article below will tell you why DLP projectors struggle with projecting an equal rate of image quality.

Imagine a set of blinds in your room covering your bedroom window. By pulling on a rod you can have the shutters open or closed, according to if you want to let light in or not. Such is exactly how an LCD projector works. Each pixel functions like a single shutter on a set of blinds to either shine light through or to block it. DLP on the other hand is constructed of millions of microscopic mirrors or ‘pixel elements’ as pros like to call them. Each pixel element functions 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 picture reaches your screen is absolutely significant with regard to image quality, brightness and colour accuracy. LCD projectors direct white light from the lamp by dividing it into red, blue and green components, by three mirrors which send the coloured light to 3 different LCD panels. The 3 LCD panels cast the elements of the image by turning each pixel on and off. The pixels are then combined in a glass prism to send the projector image. A point to realise about LCD projectors is that all three colours are directed onto your projected surface simultaneously. The way a DLP projector runs is very different and even the produced 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 forming an image creates a sequence of red, blue and green light. The millions of micro mirrors as described above reflect the coloured light on the pixels to form the image elements. The elements of the image are displayed in sequence on the screen, one colour at a time. The viewer’s eyes will then combine each coloured element of the image into a complete image. With LCD projectors, all colours are available all the time to create the highest brightness and fantastic colour accuracy. In DLP, just one colour is available at once, and so resulting in lower colour brightness and accuracy. Some manufacturers have placed a white segment in the colour wheel to improve brightness overall, but this goes and damages colour accuracy.

I see in forums all the time that DLP offers a higher contrast ratio and as such must be better. 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 technology is capable of producing. DLP projectors do have high contrast specifications compared to a majority of LCD projectors. At a glance, this can seem to be an advantage, however, in the real world, the true black level is determined by the ambient light in the room where the projector is being used. Do not be tricked by contrast specifications on websites and in brochures.

When the content you plan to bring to life has moving images, DLP projection technology also has image imperfections, or ‘artifacts’. The most often seen artifact that a DLP projector creates with moving images is colour break up. Colour break up is inherent in DLP systems because moving images change up between the time red, blue and green colours are pulled up. LCD projectors do not have this disadvantage because all colours are delivered simultaneously. DLP builders have come up with 3DLP solutions using 3 chips to answer the colour break up problem, but the price tag of these projectors make them impractical for most businesses and consumers.

Another point of difference between LCD and DLP is how they compensate for the refractive qualities of light. Take yourself back to high school science, and they taught you how various colours of light refract various amounts when directed through the same lens. The downfall 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 obviously not the same and refract light at different levels. Usually with a DLP projector, some yellow colour will appear above and some blue will come up below an image containing something as simple as a single black line. While being built LCD projectors can be adapted to minimize these effects on the projected image, because each colour is projected on a separate LCD panels.

The sole actual advantage (excluding price) with picking a DLP projector is its smaller overall size and weight. However, this is only relevant with regard to mobility and has to be traded off against the image advantages of LCD projectors. If overall picture quality is vital to you, then the decision is simple. Take an LCD projector! LCD projectors will consistently make bright, colourful images with fewer image mistakes. If you want to find out more about LCD technology in more detail, have a look at this fabulous resource website: Explore 3LCD. If you have any more questions, visit Projector Central and send me an email.

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