Which is better DLP or 3LCD?

How does a DLP know when lamp is bad?

• Does anyone know what causes the LED's on a DLP TV to let you know the lamp is going bad? Take for instance that you replace your DLP lamp. Now your TV is good for 2000-5000 hours. When the lamp is going bad the LED's start to flash and TV shuts down. All you do is replace the lamp and do not reset anything, and it works fine. How is it possible that the TV knows that the new lamp is in. If the old lamp is still good but the timer goes off can it be reset to get maxium life out of Lamp and just not off the timer. I tried to take old lamp out and put it back in to see if anything would reset. I had no luck. I have seach all over for schimatics on the PT50DL24 Akai 50inch and no luck. Any TV service personal out there can you explain to me the logics behind the DLP lamps. Thanks

• Answer:

  Not only DLP, any LAMP based TV works the same way. They meassure current comsumption for the lamp. Lamp's resistance is normally low, but as you use it the internal electrodes degenerate and that increases the resistance.... this means the lamp consumes less current (hence less brightness on the screen). The circuitry senses the current consumption. When it falls below a treshold value the circuitry knows that it is time for change and will proceed to flash the correspondent LED and shutdown the TV. A new lamp has a small resistance so it consumes more current... When you install a new lamp the current increases again and the circuitry knows that lamp is ok and let the TV work.