Accession Number : ADA323106

Title :   Recognition Time for Dial-Type Numerals as a Function of Size and Brightness.

Descriptive Note : Technical rept.,

Corporate Author : TUFTS COLL MEDFORD MA INST FOR APPLIED EXPERIMENTAL PSYCHOLOGY

Personal Author(s) : Crook, Mason N. ; Baxter, Frances S.

PDF Url : ADA323106

Report Date : MAR 1951

Pagination or Media Count : 33

Abstract : Recognition time as a function of digit size and brightness was determined for white dial type digits on a dark ground. The brightness range was from 0.003 to 0.1 foot-lambert. Average recognition time under the most favorable conditions tried was about 0.6 second. As size or brightness decreased, recognition time increased, at first slowly and then more rapidly. The effect of such secondary factors as individual differences, grouping of digits, and reduction in brightness contrast was relatively small when size-brightness conditions were favorable, but tended to be much larger when size-brightness conditions became difficult. So far as the variables here investigated are concerned, it would be desirable to maintain operational conditions such that single digits would be recognized by the median subject within about 0.7 second. The necessary size-brightness combinations, however, would involve complications with space limitations and dark adaptation, so practical compromises are necessary.

Descriptors :   *REACTION TIME, *BRIGHTNESS, *VISUAL PERCEPTION, *ALPHANUMERIC DATA, CONTRAST, COCKPITS, PERFORMANCE TESTS, PERFORMANCE(HUMAN), OPTICAL IMAGES, ILLUMINATION, HUMAN FACTORS ENGINEERING, DARKNESS, PERCEPTION(PSYCHOLOGY), VISUAL ACUITY, OPTICAL CHARACTER RECOGNITION, DARK ADAPTATION.

Subject Categories : Psychology
      Human Factors Engineering & Man Machine System

Distribution Statement : APPROVED FOR PUBLIC RELEASE