Accession Number:

ADA073448

Title:

Evaluation of Microencapsulated Phosphors.

Descriptive Note:

Final rept. 1 Jul 78-28 Feb 79,

Corporate Author:

BATTELLE COLUMBUS LABS OH

Report Date:

1979-05-01

Pagination or Media Count:

50.0

Abstract:

To determine how encapsulation affects the light output of electroluminescent phosphors, direct comparisons were made between plain and microencapsulated phosphors of the same control lot with nominal 0.5, 1.0, and 3.0-micron walls. Light output was normalized with respect to the amount of phosphor as a general procedure. Examination under magnification revealed that the encapsulating coatings formed diametric protrusions on the phosphors however, theoretical studies subsequently indicated that the conical shaped ends probably would not act as light tubes to enhance the apparent light output. Factors such as coating thickness, phosphor composition and concentration, spectral emission, and origin of the emission were studied. Shifts of emission wavelength and emission peaks were noted with decreasing temperature down to about - 265C for both UV and electrical excitation. Encapsulation had no significant effect on the output of UV excited phosphors. The program was concluded with work to confirm the results of initial AFML work which had indicated that microencapsulation enhanced the light output of phosphors. The original results were not confirmed although the same procedures and material lots were used. Author

Subject Categories:

  • Industrial Chemistry and Chemical Processing
  • Miscellaneous Materials
  • Test Facilities, Equipment and Methods
  • Nuclear Physics and Elementary Particle Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE