By Topic

Arc spot formation on cold cathodes in high-intensity discharge lamps

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

3 Author(s)
Lenef, Alan ; Osram Sylvania, Beverly, MA, USA ; Budinger, B. ; Peters, C.

Application of a fixed high-current breakdown pulse to a high-intensity discharge (HID) lamp causes the voltage to collapse rapidly to a few tens of volts in less than a microsecond. This cold cathode state is characterized by high-current density arc, attachment spots. We have investigated the transition to this state in lamp starting conditions by applying high-voltage pulses to quartz HID arc tubes filled with Hg-Ar and Ar. We find that a transition from the abnormal glow to the cathode arc-spot regime occurs at different, fill dependent currents. Average cathode electric field estimates at the transition currents confirm that field enhancement factors f of 100-300 would be needed for a strictly field emission-induced transition. Preliminary atomic force microscopy images of electrode surfaces show only large numbers of low f features. High-speed monochromatic imaging and spectroscopy show qualitative differences between Ar-Hg and Ar-only fills because of condensed mercury on the tungsten electrodes. Results suggest that, in the case of Ar-only fills, Ar ions play an important role in the initial formation of the arc spots

Published in:

Plasma Science, IEEE Transactions on  (Volume:30 ,  Issue: 1 )