Data Sheet

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35／40
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.
Viewing
directio
n
α
12 o'clock
direction 90°
9 o'clock
θ
direction 180°
3 o'clock
direction 0°
6 o'clock
direction 270°
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