This additional lighting may be accomplished through the use of specific task lighting. Light reflected from the computer screen can produce a veil of light over portions of the screen reducing contrast and visibility of the display characters. It can also form disturbing reflections of nearby or distant objects. Filters can be placed over the computer screen to reduce glare and reflections. However, filters should be considered only as a supplement, not a replacement, for control of light and reflections through proper lighting design and computer placement.
Windows are a major source of glare in many offices.
Computer operators should avoid facing an unshaded window since the difference in brightness between the screen and the area behind it may be extremely stressful and uncomfortable. Operators should also not sit with their back to an unshaded window since they will cast annoying shadows on their computer screen. Adjustable shades, curtains or blinds should be used to effectively control light levels throughout the day. Computer and Workstation Design and Placement Proper ergonomic design and adjustment of the computer and the work environment can increase productivity and worker comfort by decreasing the visual demands of the task. Overall display legibility is an important factor in visual performance.