1. facts, myths and our selling points
UHP vs Xenon
facts, myths and our selling points

2. a light source is a light source is a...?
in the fierce projection market you have several illumination technologies available
UHP (Ultra High Performance)
Xenon
LED
Laser
the UHP and Xenon lamps are by far the most popular
the lamps differ quite a lot and you will find arguments for both lamps

3. UHP™ (Ultra High Performance)
Mercury arc lamp
Same principle as Metal Halide lamp, but uses gas for stable light excitation
The arc gap is 1-1,3mm across (2,0 or more for Metal Halide) which yields greater efficiency (“point source”)
a 100W UHP lamp is capable of delivering more brightness than a 250W MH lamp
Advantages of a small arc gap increases as the imaging devices (DMD) become smaller

4. Xenon Xenon arc lamps Traditionally used in film projection
Native Colour Temperature is close to the noon sunlight
Chromacity closely approximates a heated Black Body radiator
Perfect for use in Ultra violet radiation systems as well as near Infra Red due to the Xenon wavelength

5. UHP selling points Colour benefits Cost Lamp Life Environmentally
great and stable colours over time
dual lamp systems yields better brightness uniformity (if light engine is designed properly)
Cost
the UHP lamps are far cheaper than the Xenon lamps
Lamp Life
the UHP lamps has generally a much longer life span than Xenon (up to 5000 hours, eco mode)
Xenon lamps lose brightness faster than UHP
Environmentally
a UHP lamps give you more brightness per W consumed compared to the Xenon lamps
Flexibility
24/7 and uptime; It is preferrable to have a system of 2x300W lamps than a single lamp system (hot swapping of single lamp!)
(Low) Operational Hazards
the UHP lamps has low pressure and represents a smaller hazard to the user when handling the lamps compared to the Xenon lamps

6. Xenon selling points Colour benefits High power! DC operation
native colour spectrum close to Noon Sunlight, or D65
High power!
yields very bright projection systems
DC operation
Better colour wheel control with DC compared to AC operation
Instant OnOff
supports on/off (restrike) with minimal effect on colour projection
less than 60 seconds warm up time
Single lamp design advantages
no color balancing
easier lamp replacement
reduced optics for light coupling

7. UHP counter arguments for Xenon’s USP
Colour benefits
Solved with optical filters! The UHP lamp has a decent colour spectrum, no IR and no UV with proper designed optics
High power!
UHP lamps increases in power and efficiency all the time! For mainenance cost and lamp hours a system of 2x or 4x UHP lamps is clearly preferrable. But to reach 20-30K Lumens you need Xenon!
DC operation
Philips VIDI’s digital lamp driving solves the major challenge about colour timing related to colour wheel spin cycle (see VIDI slide later)
Instant OnOff
Who cares? Who really need to use the projector within seconds after you turn it on – if you care about image quality?
Single lamp design
You have single lamp UHP systems too... ;)
A good designed dual lamp system allows you to hot swap lamps and to have better brightness and colour uniformity

8. UHP vs Xenon Colour Spectrum
Xenon is much better ”out of the box”
UHP with filters and a good optical design provides D65 brightness (noon sunlight) and stable colour performance over time!
Yellow: peak performance of UHP lamps
Blue: Flat spectrum of solar light
Red: Solar-like spectrum of the Xenon lamp

9. Xenon hazards (an extract)
Source: USHIO (lamp manufacturer)
Xenon Arc Lamps could burst when not in operation causing serious injuries!
Xenon Arc Lamps have a high internal pressure. Depending upon the lamp, the internal pressure can exceed 10 ATM or 147 PSI, even when not in operation.
.Always wear eye/face and body protection when handling Xenon arc lamps!
Never bump, drop, apply excessive stress, or scratch the lamp. This could cause the lamp to burst!
Xenon arc lamps should not be used beyond their rated service life. Operation beyond the rated service life will cause the lamp to burst.

10. Philips VIDI™
A variation of UHP technology, with new lamp driving technology
Lots of benefits due to improved control of the pulsing:
Brilliant Pulse allows us to peak segments of the colour wheel
Dark Pulse allows us to lower brightness to a 25% level results in gray scale improvement (up to 2 bits)
Tuned Plateau allows us to set controlled brightness in all colour segments to boost white or to boost red, etc
Improved BrilliantColor™ performance over lamp life time
Improved RealColor™ handling

11. Philips VIDI™ lamp technology