Datasheet

9-3) Reflection Ratio
The reflection ratio is expressed as:
R = Reflectance Factor
white board
x (L
center
/ L
white board
)
L
center
is the luminance measured at center in a white area (R=G =B=1). L
white board
is the luminance of a standard white board. Both
are measured with equivalent illumination source. The viewing angle shall be no more than 2 degrees.
α
Viewing
direction
θ
12 o'clock
direction 90°
3 o'clock
direction 0°
6 o'clock
direction 270°
9 o'clock
direction 180°
9-4) Bi-stability
The Bi-stability standard as follows:
Bi-stability Result
24 hours
Luminance drift
AVG MAX
White state △L* - 3
Black state △L* - 3
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