Lamp & Laser Life Calculator

Light Source

Presets fill in example ratings from published manufacturer data (see the notes below). Always use the figures for your own lamp or projector: the manufacturer's data wins over this model.

Minimum Acceptable Output

Usage & Running Cost

Costs are your own figures; the defaults are examples only.

Results

Output over Life

Modelled output against running hours, with your target and today's hours marked.

Xenon Lamps: Boost Current & Safety

• Boosting current over life. A new xenon lamp is usually run below its maximum power and turned up as it ages so the screen stays at the target luminance (projector auto-light features, such as Christie's LiteLOC, do this automatically). SMPTE ST 431-1 notes that screen luminance falls with lamp age and that lamp current can be reduced to bring a brighter format back into range. Enter the output at the lamp's maximum allowed power above: the "below target" point is then when even full power can no longer reach your target.
• Replace by the rated hours. Xenon lamps are under high internal pressure, hot and cold, and the risk of failure rises with age. Do not run a lamp beyond the manufacturer's rated or warranty hours, even if it still looks bright enough, and log hours accurately because warranty claims depend on them.
• Personal protective equipment. Osram's XBO handling guidance: wear a face shield with neck protection, a protective jacket and cut-resistant gloves whenever a lamp is out of its protective case, including when packing, fitting or removing it. Handle lamps only once they have cooled to room temperature, keep the protective cover on until the lamp is secured, and run lamps only in the purpose-built lamphouse.
• Follow the in-pack leaflet and the projector manual for the change procedure, cooling time, polarity, torque and safe disposal of used lamps.

Notes & References

• The model. Exponential: output = 100 % × (EOL)^{hours ÷ rated}. Linear: output falls in a straight line from 100 % to the end-of-life percentage at the rated hours. Real lamps and lasers don't follow either curve exactly, so treat the results as planning estimates and measure screen luminance regularly. Beyond the rated hours the curve is extrapolated.
• Ratings aren't comparable across makers. Some quote hours to 50 % output, others to 70 % or 80 % (L50 / L70 / L80); always enter the percentage the rating is quoted to. Laser lifetimes also depend on the output level and ambient temperature they're run at.
• Cost per hour = replacement cost ÷ replacement interval + power (kW) × electricity price. The interval is whichever comes first: the rated life or the hours at which output falls below your target. Annual figures use 52.18 weeks per year.
• Xenon: Christie lamp product pages (CDXL-20: estimated average life 3,500 h; CDXL-30SP: 2,000 h). Osram, The New Generation of XBO Cinema Projection Lamps (maximum light loss of 50 % over life; aim of 20–30 % on average). Osram XBO product safety information (PPE and handling).
• UHP: Epson projector lamp specifications (e.g. EX5250 Pro, about 5,000 h Normal / 10,000 h ECO; lamp life is the time to 50 % of initial brightness).
• Laser: Epson light-source specifications and Panasonic FAQ (about 20,000 h to 50 %); Christie, How can I use a laser projector for a longer life? (50,000 h to 80 % at 25 °C).
• SMPTE ST 431-1:2006, Annex A.2–A.3 (luminance falls with lamp age; lamp current adjustment).