Accession Number:

AD0639371

Title:

The Effect of CRT Bias on Visibility of Targets on a Remote PPI

Descriptive Note:

Memorandum rept.

Corporate Author:

JOHNS HOPKINS UNIV BALTIMORE MD PSYCHOLOGICAL LAB

Personal Author(s):

Report Date:

1946-12-10

Pagination or Media Count:

14.0

Abstract:

The cathode ray tube of a VD remote PPI indicator has an optimal bias level with respect to target visibility. Every experiment in which CRT bias was varied yielded a curve of visibility with a maximum lying somewhere between the lowest and highest intensity CRT bias settings. In all cases maximum visibility was obtained with a moderately bright, light yellow background, that is, with a comparatively low bias, and not with the dark or high bias background frequently employed by trained operators. The exact specification of this optimal level in volts or in units of illumination is not yet possible with existing measuring instruments. However, it can be fairly well defined visually.

Subject Categories:

  • Electrooptical and Optoelectronic Devices
  • Active and Passive Radar Detection and Equipment
  • Human Factors Engineering and Man Machine Systems

Distribution Statement:

APPROVED FOR PUBLIC RELEASE