Research on the Dimming Characteristics of Short Arc Ultra-high Pressure Mercury Lamps for Projection Applications
Abstract：The voltage,current and power are measured for short arc ultra-high pressure mercury lamps（UHP） with a rated power of 250W driven by 50Hz square waveform power supply.It is found that the curve slope of voltage-current characteristics is positive in most of the power range,and negative around 170W.The photometric,colorimetric and electric parameters are measured with an integrating sphere system coupled with a spectrometer in the UHP dimming experiments.The results show luminous flux increases with power linearly.The luminous efficacy and color rendering index（CRI） reduce with power reduction because of the decrease of spectral continuum.The mercury pressure are calculated with the full width at the half maximum of 546nm spectral band,which is 6.2~11.0nm.The pressure range from 15.3 to 25.8MPa corresponding to the UHP power from 43 to 258 Watts.
Keywords：projectionshort arc ultra-high pressure mercury lamp(UHP)dimmingvoltage-current characteristicsspectral line width
Publication Date：2012-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 1-5 )