One of the few LCD projector parts that can be replaced is the projector lamp. LCD projector lamps vary by model, so selection usually depends on the manufacturing company and types such as Incandescent, Compact Fluorescent, Halogen, and HID such as Metal halide and Low/High Pressure Sodium, 3M Projector, Full Spectrum, and Ballasts, to name a few.
The total lamp life is the expected operating time of the projector lamp, which is expressed in terms of hours. Most LCD projectors use a metal halide source with a lamp life of 750 to 4,000 hours or more. Lamp life is not a very useful measurement, since they gradually grow dimmer without burning out and will continue to function even if they are too dim to be considered usable. So the term “peak lamp life” - the time the lamp will last at eighty to ninety percent of total brightness – is commonly used by manufacturers.
In contrast to metal halide lamps that burn with a very white light, halogen lamps burn with a yellowish light, at a steady rate, and have a consistent brightness throughout lamp life; but they only last approximately seventy hours per bulb. Therefore, they are also less expensive.
LCD projector lamps last the longest when the LCD projector is operated in "economy mode," frequently powered down for cool-down periods, and operated in a clean, fairly dust-free environment. Projectors that are subjected to constant use have the highest probability of lamp failure before the end of the rated hours.