22"LCD Color Monitor
Dell E228WFP
18
4.5 Definition of Pixel Defects
4.5. 1.Description
These inspection standards shall be applied to LCD Module supplied by CHI MEI Optoelectronics Corporation.
4.5.2 The environmental condition of inspection
The environmental condition and visual inspection shall be conducted as below.
(1) Ambient temperature: 15~25
℃
(2) Humidity: 25~75 %RH
(3) External appearance inspection shall be conducted by using a single 20W fluorescent lamp or
equivalent illumination.
(4) Panel visual inspection on the operation condition for cosmetic shall be conducted at the distance
35cm or more between the LCD module and eyes of inspector. And, the viewing angle shall be 90
degree to the front surface of display panel.
Ambient Illumination: 400 ~ 600 Lux for external appearance inspection
Ambient Illumination: 100 ~ 200 Lux for light on inspection
4.5.3 Classification of defects
Defects are classified two types, major defect and minor defect according to the defect. And, the
definition of defects is classified as below.
(1) Major defect
Any defect may result in functional failure, or reduce the usability of product for its purpose. For
example, electrical failure, deformation and etc..
(2) Minor defect
A defect that is not to reduce the usability of product for its intended purpose and un-uniformity, dot
defect and etc..
The criteria on major and/or minor judgement will be according with the classification of defects.
4.5.4 Inspection Criteria
(1) Definition of dot defect induced from the panel inside
a) The definition of dot: The size of a defective dot over 1/2 of whole dot is regarded as one defective dot.
b) Bright dot: Dots appear bright and unchanged in size in which module is displaying under black pattern.
c) Dark dot: Dots appear dark and unchanged in size in which module is displaying under pure red, green, blue
picture.
d) 2 dot adjacent = 1pair = 2 dots
Picture:
2 dot adjacent 2 dot adjacent 2 dot adjacent (vertical) 2 dot adjacent (slant)
Summary of Contents for E228WFP
Page 19: ...22 LCD Color Monitor Dell E228WFP 19 2 Display Inspection 3 Appearance inspection ...
Page 36: ...22 LCD Color Monitor Dell E228WFP 36 8 PCB Layout 8 1 Main Board ...
Page 37: ...22 LCD Color Monitor Dell E228WFP 37 ...
Page 38: ...22 LCD Color Monitor Dell E228WFP 38 8 2 Power Board ...
Page 39: ...22 LCD Color Monitor Dell E228WFP 39 ...
Page 40: ...22 LCD Color Monitor Dell E228WFP 40 8 3 Key Board ...
Page 53: ...22 LCD Color Monitor Dell E228WFP 53 2 Select Commands Batch ...
Page 55: ...22 LCD Color Monitor Dell E228WFP 55 12 Exploded View ...