Abstract

An investigation was undertaken of phosphors capable of converting primary ultraviolet radiation (Hg line, 2537 angstroms) to radiation in the erythemal or sun tan ultraviolet region (2900–3200 angstroms). Several types of alkaline earth silicates and phosphates activated with lead or thallium were found to be practical. Among these was a calcium phosphate activated with thallium and containing about 1.3 moles of calcium per mole of phosphate. This phosphor not only showed a good initial erythemal emission, but when used in an experimental fluorescent lamp maintained a high percentage of this emission for the several hundred hours tested. The lamp was constructed of special glass and coated with the above phosphor, but otherwise was similar to commercial fluorescent lamps. In addition, the investigation showed some similar types of phosphors to be efficient in the neighboring “black-light” ultraviolet region (approximately 3400–3800 angstroms), and to give more emission in that region than the cerium-activated phosphors commonly used at present. Some discussion of sun tan lamp and fixture design is also included.

© 1947 Optical Society of America

Full Article  |  PDF Article
OSA Recommended Articles
Fluorescence of Silicate Phosphors*

Keith H. Butler
J. Opt. Soc. Am. 37(7) 566-571 (1947)

The Fluorescence of Phosphors in Rare Gases

N. C. Beese
J. Opt. Soc. Am. 36(9) 493-498 (1946)

Causes of Early Loss of Light Output of Fluorescent Lamps

George Meister and Rudolph Nagy
J. Opt. Soc. Am. 36(12) 696-701 (1946)

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Figures (7)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Tables (7)

You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription