Introduction To Display Troubleshooting - Nokia RM-596 Service Manual

RM-596
BB Troubleshooting and Manual Tuning Guide
Visual defects (pixel)
Bright sub-pixels
Dark sub-pixels
Combined sub-pixel
Temporal sub-pixels
Item
1
2
3
Note: Blinking pixels are not allowed in normal operating temperatures and light conditions.

Introduction to display troubleshooting

The display module used is based on AM OLED technology and supports display format of 360 columns x 640
rows. The dimension of the display module is 47.8 mm x 86.3 mm x 2.12 mm. The module will interface to
the phone via FPC with a 20 pins board to board connector.
The following references on the PWB help in the effective debugging and troubleshooting of the display.
Issue 2
Defect counts
Combined sub-
pixel defect
Temporal sub-
pixel defect
COMPANY CONFIDENTIAL
Copyright © 2010 Nokia. All rights reserved.
Pixel defects can be checked by controlling the
display with Phoenix. Use both colors, black and
white, on a full screen. R, G, B are also helpful.
The display may have some random pixel defects
that are acceptable for this type of display. The
criteria when pixel defects are regarded as a display
failure, resulting in a replacement of the display, are
presented in the following table.
Table 7 Pixel defects
(sometimes called on-pixels or stuck-on) are
characterized by the appearance of bright/colored
pixels in, for example, black full screen picture.
(sometimes called off-pixels, stuck-off, or black
pixels) are characterized by the appearance of dark
pixels in white, red, green, or blue full-screen
picture.
defects are characterized by at least two sub-pixels
defects (bright or dim) being closer than 5 mm to
each other.
(sometimes called blinking defects) exhibit
temporal variations not related to any steady-state
video input. Temporal sub-pixel defects may be
intermittent, exhibit a sudden change of state, or
be flickering.
Table 8 Defects table
Bright dot (sub-
pixel) defect
Not allowed
Not allowed
Not allowed
Dark dot (sub-
pixel) defect
Total
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