NEC MultiSync FE001SB, Service Manual

Page: 95 / 178

5-29
Standards
Average diameter classified by a contrast (Note 1) (mm) Allowable number
High contrast Middle contrast Low contrast Zone A Zone B
Allowable
Length (mm)
~ 0.10 ~ 0.20 ~ 0.50 Ignore Ignore -
0.11 ~ 0.25 0.21 ~ 0.50 0.51 ~ 1.25 2 [4] 4 [5] 20
0.26 ~ 0.50 0.51 ~ 1.00 1.26 ~ 2.50 1 [4] 2 [4] 40
0.51 ~ 0.75 1.01 ~ 1.50 2.51 ~ 3.75 0 [4] 1 [4] 80
Values inside [ ] represent acceptable number in low contrast.
See the table in the next page for total defect number, which is acceptable in low contrast.
Note 1: Convert (a+b)/2 or a/20 + 2b small value into average diameter. (a: length, b: width)
total number of a low contrast flaws Zone A Zone B
Standard classified by zones 6 8
Total ( zone A + zone B ) 10
Note 1: Acceptable interval shall be larger one in the case that defects have different interval.
Note 2: There is no standard regarding zone C. Therefore, no defect is accepted that may deteriorate the
value of products. Defect level by consultation. Discuss is necessary.
Note 3: Tolerance of defect size is approx. 10%.
6.2.4 Irregularity of reflected color
Irregularity of reflected color that is easily visible should not be recognized. (K coat)
Irregularity of reflected color that influences Raster easily should not be recognized. (AR Film)
6.2.5 Dirt, cloudiness, no uniformity and other defects
The defects shall not be recognized when the green raster is produced over the screen. If necessary, the
limit sample is provided.