Datasheet

9. Optical characteristics
9-1) Specifications
Measurements are made with that the illumination is under an angle of 45 degrees, the detection is perpendicular unless otherwise
specified.
T=25℃
SYMBOL PARAMETER CONDITIONS MIN TYPE MAX UNIT Note
R Reflectance White 30 35 - %
Note
9-1
Gn 2Grey Level - - DS＋(WS-DS)×n(m-1) - L* -
CR Contrast Ratio indoor 8 - - -
Panel’s life 0℃~50℃ 1000000 times or 5 years
Note
9-2
WS: White state, DS: Dark state
Gray state from Dark to White : DS、WS
m: 2
Note 9-1: Luminance meter: Eye – One Pro Spectrophotometer
Note 9-2: Panel life will not guaranteed when work in temperature below 0 degree or above 50 degree. Each update interval time
should be minimum at 180 seconds.
9-2) Definition of contrast ratio
The contrast ratio (CR) is the ratio between the reflectance in a full white area (R1) and the reflectance in a dark area (Rd)() :
R1: white reflectance Rd: dark reflectance
CR = R1/Rd
Display
Detector
Ring light
θ
4.2" e-Paper
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