NEC MultiSync LCD1550V Service Manual page 50

2. External inspection on the LCD module
Inspection condition is approximately 15-50cm
Viewing angle is normal to the LCD panel.
Ambient temperature is in the room temperature.
Ambient illumination is 300-500Lux.
Display characteristics
Visual defect
D: Diameter
N: Number
W: Horizontal width
L: Vertical high
Electrical defect
N: Number
Defect type
Dark / Bright Spot
Circular Foreign Material
Bright or Dark Line
Foreign Material
Polarizer / Linear Scratch
Polarizer – bubble / Peeling
Maximum Allowable Defect
Count All Types
Bright Dot Random
Bright Dot 2 Adjacent
Dark Dot Random
Dark Dot 2 Adjacent
Dark Dot 3 or More Adjacent
Total Bright and Dark Dots
Minimum Distance Between Bright Dots
Minimum Distance Between Dark Dots
Minimum Distance Between Bright Dots
and Dark Dots
5-4
Criteria
0.2mm≤D<0.5mm
N≤4
0.05mm≤W<0.2mm
0.3mm≤L≤3mm
N≤4
0.01mm≤W<0.2mm
1.0mm≤L≤10mm
N≤3
0.15mm≤D<0.25mm
N≤4
N≤7
N≤4
N≤2
N≤4
N≤3
N=0
N≤4
≥15mm
≥10mm
≥10mm