52.1: Invited Paper: New Developments in Projection Light Sources—Shorter Arcs and Miniaturisation

Abstract

New developments of UHP lamps with higher power and shorter arcs (even below 1mm) fulfill the optical demands of future projectors and novel displays. In addition a new technology is presented which leads to a reduction of the lamp ignition voltage from 20kV to 5kV. This enables a further step in system size reduction.

50.1: The Improvements of CPT LCOS Television

“…[2]The lamp max coupling efficiency(Φ lm) as a function of system etendue(E) and arc size (d) is presented in Figure 1 [3],which is formulated from equation (1). [4] For a 0.7" panel and F/#=2.8 projection lens, the etendue is calculated about 14 mm 2 -steradian,so 65% light collection is usable for 1.0 arc lamps. Table 1 shows various combinations of panel size diagonals and F/#.…”

UHP lamps for projection

“…12). 12,13 The seal is made in such a way that some millimeters in the middle are simply not closed, leaving a small cavity with the molybdenum foil going through it, which is filled with an argon-mercury mixtures. An external wire ("antenna") creates an electrical field and a first ignition takes place inside this small cavity.…”

“…The speed at which these devices can enter the marketplace therefore depends on the availability of improved light s o u r c e s w i th s m a l l e r s i z e a n d ev e n s h o rter ar c lengths. 5,7,8,11,13 2…”

Ray tracing software application in VIP lamp design

“…Successful new projectors show enhanced brightness, reduced size, and a lower noise and price. The main direction in discharge lamp development is therefore towards higher wattage and shorter arcs to enable a higher screen illuminance at smaller panel sizes 1,2 . However, other lamp improvements serve the projector industry as well: higher collection efficiency may avoid increasing the lamp power for projector upgrades.…”