Microsoft Xbox Repair Manual page 22

Now you have access to both the lens.
and the mirror
Blast the optics with canned air, and then continue on to the blast the rest of the DVD chassis
trying to blow the remainder of the dust away from the optics. Using a Q-tip, clean the mirror and
the lens with a high quality lens cleaner. I like to use anti static lens cleaner but any glass cleaner
should work, I have even heard of plain alcohol being used. The goal is to leave a streak free
finish and use one end of the wetted q-tip to clean and the other to dry. BE CAREFUL NOT TO
SCRATCH THE MIRROR
One DVD in my collection had a single fiber from cloth on the outside of the mirror, this
seemed to be the major cause of the problem but the drive still suffers from occasional
errors.
"Here's a picture I just made showing all the parts involved in directing the laser to the disc and
back. Here you'll see that just cleaning the top lens and the bottom mirror isn't really enough.
This is the lens piece without the top lens section. In total, there are 11 sections in that little piece
that need to be cleaned to bring the drive back to full potential.
Also notice in the picture the SENSOR is detached from the main body. The little opening in
between the sensor and the last focus lens (bottom left) is the most important place to be cleaned
and can easily be done with compressed air."
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