Community Research and Development Information Service - CORDIS

Abstract

This report describes the work carried out at NPL and PTB to improve the performance of a low pressure deuterium discharge lamp, so that it can be used as a transfer ? standard in the special range 120 to 350 nm. To this end it was necessary: + to replace the original quartz windows by magnesium fluoride single crystal plates, which were cut perpendicular to the c-axis of the crystal and which had to be free of impurities, + to construct the lamps in such a way that the directional uniformity of the emitted radiation is within the demands, + to age the lamps and to preselect only those of which the irradiance was stable within +- 1% during a thirty minute period after warm-up, + to improve the commercially available electrical power supply to meet the operational needs of the lamps. A liquid nitrogen trap has been developed which can be installed between the vacuum system and the lamp. This reduced to about 2% the decrease of the window's transmission during the first hour of operation, caused by the deposition of oil from the vacuum system.

Additional information

Authors: KEY P J, NATIONAL PHYSICAL LABORATORY, TEDDINGTON, MIDDLESEX (UK);NETTLETON D H NATIONAL PHYSICAL LABORATORY, TEDDINGTON, MIDDLESEX (UK), NATIONAL PHYSICAL LABORATORY, TEDDINGTON, MIDDLESEX (UK)
Bibliographic Reference: EUR 10234 EN (1985) MF, 67 P., BFR 150, BLOW-UP COPY BFR 335, EUROFFICE, LUXEMBOURG, POB 1003
Availability: Can be ordered online
Record Number: 1989124102500 / Last updated on: 1987-01-01
Category: PUBLICATION
Available languages: en
Follow us on: RSS Facebook Twitter YouTube Managed by the EU Publications Office Top