Bezel gloss and glare

Abstract

Two studies were performed to examine whether reflections in the glossy surround of computer displays gave rise to ergonomic problems of reduced visual performance or discontent. The approach taken was not to assess whether or not problems were present under typical environmental conditions, which would risk missing problems, but rather was to determine conditions under which problems did exist. Once this was done, it was then possible to evaluate whether the gloss of commercially available products would be acceptable or unacceptable in more normal surroundings. In the first study, visual performance was assessed by evaluating sensitivity to contrast when five different screen surrounds (‘bezels’) were used. All six of the participants showed a decrease in sensitivity when the reflection of a lamp, of luminance 1000 times that of a typical fluorescent lamp, was seen in a mirror-like surround. When a black glossy surround was used, a tiny decrement was seen for two older participants, who were past the UK retirement age, but not for the other four pre-retirement age participants. No decrement was detected when a light silver-grey glossy surround was used. When the lamp luminance was reduced by a factor of 100 (but was still 10 times higher than that of a typical fluorescent lamp) no decrement was seen in the performance of any of the participants, even when the mirror-like surround was used. In the second study, assessments were made of the displays on five different subjective scales following the reading of text for 20 min. Eight surrounds were used, three of which were identical in every respect, apart from the glossiness of their bezels. Variation in acceptability was found amongst the surrounds, and both a shiny mirror-like surround and glossy black surround were considered to be unacceptable overall. However, the comparison between the three identical displays revealed no significant differences in acceptability, and we conclude that gloss per se does not give rise to ergonomic problems in acceptability unless there is a very high contrast between the reflection and the surround.