Written by Mike Sessler
Last time, we touched on the basic, underlying technology of LCD and DLP imaging systems. Today, we will look at some of the pros and cons. As I said last time, much has been written on this subject, and I am not going to be exhaustive here. If you want a very thorough look at this, albeit from a home theater projector perspective, check out this article at Projector Central.
- LCD projectors are generally less expensive than 1-DLP units at a given brightness. This is a general rule, and there are plenty of exceptions. However, if budget is a big concern, look to LCD.
- LCD generally has better contrast. This is relative, however. Keep in mind; you are shooting the image onto a white screen. So the blackest the image will ever get is as black as the white screen ever gets.
- No rainbow effect. I sometimes notice a slight jitter in DLP images. It is not always readily apparent, and I am a trained observer. However, LCD images tend to be pretty rock-solid.
- Better apparent resolution. Because the pixels are very clearly defined, graphics tend to look sharper on LCD projectors. To some extent, this is academic now that we are getting up to 1920x1080 chipsets in both technologies, and given the average viewing distances. However, there is a difference.
- Better color saturation. Because a DLP color wheel typically has a white slot in it to boost brightness, the color saturation can be lower. LCDs behave more like LED lights; the brighter they are, the more saturated they get.
- The lifespan of panels. We do not know how long the LCD panels will last before they start breaking down. We do know they break down and the colors start to shift. Newer inorganic panels seem to hold up better than older organic designs, but some are projecting the life of an LCD panel to be between 4,000-10,000 hours. That could be 1-3 bulb changes. Of course, a lot of those tests are being done by DLP makers, so? If you are using your projector for a few hours on the weekend, and occasionally during the week, this is probably not an issue. In a big command center where projectors are on 24/7 for years, this is a problem.
- Dust. The LCD engine is not sealed, so it's possible dust can get in there. This is less of a problem with pro-grade projectors that have good filtration systems. Still, if you have a dusty environment, be aware of this.
- Screen door effect. Because the edges of the pixels are so well defined, you can sometimes see the spaces between them. It looks a bit like viewing the image through a screen door. Again, with higher resolution and tighter pixel pitch, this is less of a problem than it used to be.
- Mis-convergence. Because an LCD image is made up of three images of different colors, they have to be lined up correctly. If they are not, you will see fringing of color on vertical or horizontal lines. Again, with newer, pro-level projectors this is less of a problem. However, it does show up on budget models.
There's a look at the LCD. On Friday, we will wrap this up with a look at DLP pros and cons, and some are concluding thoughts on which one is better.