PRECAUTIONS FOR BUILT-IN LENS CMOS IMAGE SENSORS
PRECAUTIONS FOR BUILT-IN LENS
CMOS IMAGE SENSORS
1. Package Breakage
2. Electrostatic Damage
In order to prevent the package, the lens holder,
and the lens from being broken, follow the
instructions below :
As compared with general MOS-LSI, CMOS image
sensor has lower ESD. Therefore, take the
following anti-static measures when handling the
CMOS image sensor :
1) The CMOS image sensor is a precise optical
component and the package-base material is
ceramic.
1) Always discharge static electricity by grounding
the human body and the instrument to be used.
To ground the human body, provide resistance
of about 1 M$ between the human body and
the ground to be on the safe side.
2) When directly handling the device with the
fingers, hold the lens holder and do not touch
the lead.
3) To avoid generating static electricity,
a. do not scrub the device with cloth etc.
b. do not attach any tape or labels.
4) When storing or transporting the device, put it in
a container of conductive material.
Therefore,
ø Take care not to drop the device when
mounting, handling, or transporting.
ø Avoid giving a shock to the package.
Especially when leads are fixed to the socket
or the circuit board, a small shock could
break the package more easily than when
the package isn’t fixed.
2) When adjusting the focus, screw the lens holder
to the circuit board before soldering the leads.
At that time, make sure to use a circuit board
with plenty of strength, and to avoid the
package and the lens holder from being broken,
the following screw and clamp torque are
recommended.
3. Dust and Contamination
Dust or contamination on the surface of the lens
and the inside of the lens holder could deteriorate
the output characteristics or cause a scar. In order
to minimize dust or contamination on the device,
take the following precautions :
ø Recommended mounting screw :
Ø1.7 tapping screw (B-tight type),
Length, L = the thickness of the circuit board
+ 6 mm
1) Do not remove the lens from the body.
Especially when adjusting macro, be careful
not to remove the lens by turning it counter-
clockwise too much.
2) Do not touch the surface of the lens with the
fingers. If dust or contamination gets on the
surface of the lens, the following cleaning
method is recommended :
ø Recommended clamp torque : 0.012 N·m
[however, when the thickness of the circuit
board is thinner than t = 2.0 mm]
3) If any damage or breakage occurs on the
surface of the lens, its characteristics could
deteriorate.
Therefore,
ø Do not hit the lens.
ø Do not give a shock large enough to cause
distortion.
ø Do not scrub or scratch the surface of the
lens.
ø Handle the built-in lens CMOS image sensor
in a clean environment such as a cleaned
booth. (The cleanliness level should be, if
possible, class 1 000 at least.)
– Even a soft cloth or applicator, if dry, could
cause dust to scratch the lens.
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