Electroluminescent Displays (EL) for General Aviation Cockpits

From failure to success in developing a direct sunlight readable electroluminescent display for use in general aviation cockpits. Initial attempts using existing technologies resulted in failure of a product design. Using new EL driver design approaches a 76.2 mm x 127 mm EL display with an unfiltered average brightness of 65 foot lamberts (1) was developed which proved to be satisfactory across the range of dark night to bright day sunlight ambient lighting conditions within an aircraft cockpit.

A circular polarized contrast enhancement filter was developed for the EL display. Although the filter lowered the average brightness to 24 foot lamberts the overall readability was increased. EL displays may be a good alternative to other technologies for use in direct sunlight applications.