Originally Posted by RangersFan
A few questions, i'm still doing my research on DLP and SXRD sets, some people are complaining that even now after several iterations the Samsung DLP's still suffer from the rainbow effect from the color wheel. I am unfamiliar with SXRD sets, do these sets suffer from the rainbow effect? Does it have a color wheel? If not, how does it produce it's image, and it is something that will need maintenence or an extended warranty on? Thanks for any info, I originally ruled out any SXRD sets cause they all seemed so expensive, but this one might be quite the value.
SXRD is Sony's implementation of LCOS. As currently implemented, LCOS sets do not suffer from the rainbow effect, and do not use a color wheel. However, like all projection sets, they do use a light source. Just like DLP, technically the light source can be any of a bulb/lamp, LED or laser. Currently, the only laser-based projection sets are research prototypes, and the only sets that use an LED light source are DLP-based.
As currently implemented, LCOS sets use three LCOS microdisplay chips, one each for red, green and blue. All pixels are shown simultaneously. The advantage is no color wheel. The disadvantage is the possibility of misconvergence of the three LCOS chips.
Unlike LCD-based microdisplays, light is reflected off of LCOS panels. For LCD-based projectors, light must be passed through the panel. For technical reasons, there must be a small separation between each pixel in the case of LCD, which is not the case for LCOS panels. That separation gives rise to the "screen door effect" which plagues LCD and plasma screens.
There is no reason one could not use a single LCOS chip and a color wheel, nor is there any reason (other than cost) one could not use three DLP chips without any color wheel.
Sony, Brillian and JVC all make LCOS-based projection TVs. Sony is almost alone in offering no DLP-based sets.
You should get an extended warranty when purchasing any non-CRT-based multithousand-dollar televison.
In the case of the Sony SXRD sets, there is a known design/manufacturing flaw that affects some percentage of the 2005 models. It may be that the entire cohort of 2005 SXRD sets have this problem, and the problem will be manifested by all of them over time. No one knows. Also unkown is whether the 2006 SXRD sets do or do not have the same problem. The problem is affectionately known as The Green Blob.
The Green Blob starts out life as a faint green discoloration or "haze" affecting some area of the screen, but not the entire screen. It is at first essentially invisible except when the affected area of the screen is showing a shade of gray. Over time (weeks, months,) it gets worse, and eventually is visible at all times.
Some owners report seeing a similar "green blob" or doughnut for a few minutes when the set is first turned on--but this fades away after a minute or so. Currently, I don't believe this is related to the Green Blob problem, but that's just my best guess.