Planar ICEBrite EL VGA Displays EL640.480-AM - Manual (Page 16)

EL640.480-AM Operations Manual (020-0351-00C) 14
Grayscale
Using the display’s higher frame rate frequency, combined with flat panel
controllers, it is possible to generate a wider range of usable grayscales
through frame rate control and dithering.
Frame Rate Control generates true grayscales by turning pixels on and off over
several frames of time. The user’s eye sees each individual pixel as gray. The
potential problems with this method are brightness-profile and shadowing,
especially when used to shade larger areas.
Dithering generates grayscales by patterning the area to be shaded. The
tested C&T controllers use a pattern of 4 (2x2) pixels to generate the dithered
grayscales. When the area is viewed from a distance, it appears to the user’s
eye as gray. When viewed up close, the different brightness of the individual
pixels can be observed.
Many of the grayscales that can be generated may flicker or swim. Through
careful selection however, several grayscale patterns are available for most
applications, particularly when the display is driven at its maximum frame rate
frequency. Planar Application Note 119 is available for more information on
generating grayscale images.
Reliability
The MTBF (mean time between failures) is a minimum of 50,000 hours at 25°C
ambient, except for performance characteristics with an otherwise specified
life expectancy.
Safety and EMI Performance
The AM displays will not inhibit the end product from obtaining these
certifications:
Safety: UL544, IEC950
EMI: FCC Part 15/J, Class B
EN55022 Level B