Nokia RX-44 Service Manual page 150

camera body cavity contains a particle, which may move onto the image sensor active surface, e.g. when the
phone is dropped. Thus it is also possible that the problem will disappear before the phone is brought to
service.
The camera should be replaced if the problem is present when the service technician analyses the phone. If
dust particle is lying on infrared filter surface on either side, they are much harder to locate because they
will be out of focus, and appear in image as large, grayish and fading-edge 'blobs'.
Sometimes they will be very hard to find, and thus the user probably will not notice them at all since they
do no harm. But it is possible that a larger particle disturbs the user, causing need for service.
If large dust particles get trapped on top of the lens surface in the cavity between camera window and lens,
they will cause image blurring and poor contrast (see also item 'sharpness').
The dust gasket between the window and lens should prevent any particles from getting into the cavity after
manufacturing phase. If dust particles are found on sensor, this is classified as a manufacturing error of the
module and thus the camera should be replaced, since camera module cannot be dissembled without
damaging it.
Any particles inside the cavity between protection window and lens have most probably been trapped there
in assembly phase at camera module supplier. Unauthorized disassembling of product can also be root cause
for the problem.
Testing for Sharpness
Effects of Dirty or Defective Protection Window
If video image taken with some device are claimed to be blurry, there are following possible sources for the
claim:
1 Protection window is fingerprinted, soiled, dirty, visibly scratched or broken.
2 Camera module has failed to focus correctly. Producing a blurred image.
3 User has tried to take video in too dark conditions and video is blurred due to handshake or movement.
This is no cause to replace camera module.
4 There is dirt between protection window and camera lens.
5 The protection window is defective. This can be either manufacturing failure or caused by user. Camera
module should be changed.
It should be noted that the effects of any dirt in video images can vary very much; it may be difficult to judge
if the window has been dirty when some image has been taken or if something else has been wrong.
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RX-44
Camera troubleshooting
Issue 1