Projection TV Cautions
If you own a projection type television you should be aware of the following to prevent damage to your set as well as extend the life of it.
1) Be careful of any stationary images on the screen (i.e. station call sign logos, toll free numbers, stock tickers, etc) or the use of any video games or input devices that leave images in the same place for lengthy periods of time. This could also apply to putting a DVD or movie in pause for long periods of time that don't reset and go to a screen saver after a short period. These stationary type images can eventually be physically and PERMANENTLY burned into the screen and will appear forever as ghostly images in the background.
2) Newer HD sets provide the ability to watch video in the older 4:3 format which doesn't fill the screen completely and has grey or black bars at the sides of the video image. Constant use of this format will cause uneven wear of elements in the set which will eventually cause the unused portion to be different and visible as a brightness or color change at the sides of screen. This is also PERMANENT damage and should be avoided by using one of the full screen formats of the set if possible.
3) LCD and DLP type projection sets use a projection type lamp as a light source. This lamp is usually very similar in nature to a slide or movie projector lamp. The lamp uses a high voltage strike source to fire the lamp electrodes which causes microscopic pitting in the electrodes each time it fires. For this reason, the life of the lamp is somewhat related to not only lamp hours of use but number of strikes as well, since after thousands of strikes the electrodes may become to pitted to ignite the gas in the lamp. Therefore, you would be better off to leave the set on if it is only going to off a short period of time and then turned right back on again. My recommendation is that if it will be less than an hour, you should just leave it on.
4) LCD and DLP sets which use projection lamps have fans in them to keep the lamp cooled down. Be careful not to block this airflow. An overheated lamp will drastically shorten its life cycle. When your set is turned off, power is still on briefly to allow fans to cool this lamp off till it is down to a reasonable temperature. Unplugging the set from power before the lamp can adequately cool may cause the lamp to shatter or at the least shorten its life. Treat this set just like you would a slide projector or movie projector. This includes avoiding sudden jars to the set while the lamp is hot and therefore fragile. Every effort should be made to periodically vacuum the accumulated dust from the fan blower ports usually located in the rear of the set.
5) LCD and DLP sets that have projector lamps use this lamp to provide brightness and contrast to the screen. Just like any lamp, after many hundreds of hours of use its overall brightness will diminish and the screen may not be as bright as it was when it was new. This is normal for any lamp but like bad vision usually comes on so slowly as to be unnoticeable over time. It may also be noted that as a lamp ages its ability to come to full brightness at power on will be slowed down as well. This is also normal.
6) The life of your projection set regardless of its type can be extended by entering your video adjustment menu and adjusting your contrast and brightness levels down to the lowest level that you find most acceptable. The contrast is by default almost always set higher than it should be anyway and only serves to mask out fine detail as well as use up resources faster (i.e. crts, LCD devices).
1) Be careful of any stationary images on the screen (i.e. station call sign logos, toll free numbers, stock tickers, etc) or the use of any video games or input devices that leave images in the same place for lengthy periods of time. This could also apply to putting a DVD or movie in pause for long periods of time that don't reset and go to a screen saver after a short period. These stationary type images can eventually be physically and PERMANENTLY burned into the screen and will appear forever as ghostly images in the background.
2) Newer HD sets provide the ability to watch video in the older 4:3 format which doesn't fill the screen completely and has grey or black bars at the sides of the video image. Constant use of this format will cause uneven wear of elements in the set which will eventually cause the unused portion to be different and visible as a brightness or color change at the sides of screen. This is also PERMANENT damage and should be avoided by using one of the full screen formats of the set if possible.
3) LCD and DLP type projection sets use a projection type lamp as a light source. This lamp is usually very similar in nature to a slide or movie projector lamp. The lamp uses a high voltage strike source to fire the lamp electrodes which causes microscopic pitting in the electrodes each time it fires. For this reason, the life of the lamp is somewhat related to not only lamp hours of use but number of strikes as well, since after thousands of strikes the electrodes may become to pitted to ignite the gas in the lamp. Therefore, you would be better off to leave the set on if it is only going to off a short period of time and then turned right back on again. My recommendation is that if it will be less than an hour, you should just leave it on.
4) LCD and DLP sets which use projection lamps have fans in them to keep the lamp cooled down. Be careful not to block this airflow. An overheated lamp will drastically shorten its life cycle. When your set is turned off, power is still on briefly to allow fans to cool this lamp off till it is down to a reasonable temperature. Unplugging the set from power before the lamp can adequately cool may cause the lamp to shatter or at the least shorten its life. Treat this set just like you would a slide projector or movie projector. This includes avoiding sudden jars to the set while the lamp is hot and therefore fragile. Every effort should be made to periodically vacuum the accumulated dust from the fan blower ports usually located in the rear of the set.
5) LCD and DLP sets that have projector lamps use this lamp to provide brightness and contrast to the screen. Just like any lamp, after many hundreds of hours of use its overall brightness will diminish and the screen may not be as bright as it was when it was new. This is normal for any lamp but like bad vision usually comes on so slowly as to be unnoticeable over time. It may also be noted that as a lamp ages its ability to come to full brightness at power on will be slowed down as well. This is also normal.
6) The life of your projection set regardless of its type can be extended by entering your video adjustment menu and adjusting your contrast and brightness levels down to the lowest level that you find most acceptable. The contrast is by default almost always set higher than it should be anyway and only serves to mask out fine detail as well as use up resources faster (i.e. crts, LCD devices).