[reio-ta]

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[kelpie]

Hi reio-ta:


I'm no expert, but from what I understand the ideal projector lamp would have:

1. High light output
2. Broad and consistent color spectrum over the life of the lamp
3. Widely available (e.g. not a "new" or proprietary technology with limited availability)
4. "Long" life
5. Low cost

The problem is, it's hard to make a lamp with all of those properties, so display manufacturers have compromised and picked the first four (well, 3 1/2...) as the most important. Apparently they feel that their current lamps best fit those criteria. Metal halide (MH) lamps that are inexpensive and widely available often have low light output and/or limited color spectrum (or color spectrum that changes over the life of the lamp), etc. MH lamps with high light output and broad color spectrum might be proprietary, limited in availablity, vary in color spectrum over their life, are expensive, etc.


Looks to me like manufacturers are pinning their hopes for the near future on LED light sources (with longer life than current lamps) and are looking at laser light sources for the more distant future rather than trying to find just the right inexpensive metal halide lamp. I suppose they must have their reasons. Maybe someone else has a better answer.

 

[1920x1080]

Excerpts from an abstract at: http://adsabs.harvard.edu/abs/2004SPIE.5289..255W


"The past decade has seen a rapid development of projection systems. Projectors as small as only a few liters in size deliver several thousand screen lumens and are, with an efficacy of over 10 lm/W, the most efficient display systems realized today. This has been made possible by breakthroughs in lamp technology, particularly by the development of the UHP-lamp. This broadband light source with its outstanding brightness and lifetimes of over 10000 hours is ideal for projection applications." "...there is a trend towards brighter projectors, which is fostered by a brightness increase of the UHP-lamps. At the same time, projectors have seen a dramatic reduction in size, which has been made possible mostly by reducing lamp- and driver-size by even a factor of 10. This was only possible by the development of new ignition concepts as well as new optical designs of the reflector. And finally, UHP-lamps have seen quite some improvement in color rendering by using even higher pressures and shorter arc gaps. This allows for more colorful pictures and even more efficient projector designs."

 

[1920x1080]



Quote:
Originally Posted by reio-ta /forum/post/0


...10,000 hours? Thats a good one. You're lucky to have a UHP last one fifth of that. Its really sad by the time the Phillips stupid patent runs out, UHP lamps will be gone and LED and laser will have replaced them. But not soon enough for me it seems...

The UHP lamp in my KDS-60A2000 is rated at 8000 hours, FWIW. But LED and laser do intrigue me. I waited for almost a year for HP to come out with their LED-driven RP before I finally caved last Black Friday (back in the weeks leading into the holiday shopping season I literally got my KDS for almost half off its list price at the time) and bought the Sony; now that HP has dropped their RP's, I understand why it never come out. I wish Akai/NuVision/Samsung, et al, success so that others follow and the engine matures--same with Mitsubishi and laser.