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Additional Reference Information
Linea CLHS Series Camera
Sensor Handling Instructions
This section reviews proper procedures for handling, cleaning, or storing the camera. Specifically
the camera sensor needs to be kept clean and away from static discharge to maintain design
performance.
Electrostatic Discharge and the Sensor
Cameras sensors containing integrated electronics are susceptible to damage from electrostatic
discharge (ESD).
Electrostatic charge introduced to the sensor window surface can induce charge buildup on the
underside of the window that cannot be readily dissipated by the dry nitrogen gas in the sensor
package cavity. With charge buildup, problems such as higher image lag or a highly non-uniform
response may occur. The charge normally dissipates within 24 hours and the sensor returns to
normal operation.
Important
: Charge buildup will affect the camera’s flat-field correction calibration. To avoid an
erroneous calibration, ensure that you perform flat-field correction only after a charge buildup has
dissipated over 24 hours.
Protecting Against Dust, Oil and Scratches
The sensor window is part of the optical path and should be handled like other optical components,
with extreme care.
Dust can obscure pixels, producing dark patches on the sensor response. Dust is most visible when
the illumination is collimated. The dark patches shift position as the angle of illumination changes.
Dust is normally not visible when the sensor is positioned at the exit port of an integrating sphere,
where the illumination is diffuse.
Dust can normally be removed by blowing the window surface using a compressed air blower,
unless the dust particles are being held by an electrostatic charge, in which case either an ionized
air blower or wet cleaning is necessary.
Oil is usually introduced during handling. Touching the surface of the window barehanded will leave
oily residues. Using rubber finger cots and rubber gloves can prevent oil contamination. However,
the friction between the rubber and the window may produce electrostatic charge that may
damage the sensor. To avoid ESD damage and to avoid introducing oily residues, avoid touching
the sensor.
Scratches can be caused by improper handling, cleaning or storage of the camera. When handling
or storing the camera without a lens, always install the protective cap. Scratches diffract incident
illumination. When exposed to uniform illumination, a sensor with a scratched window will normally
have brighter pixels adjacent to darker pixels. The location of these pixels changes with the angle
of illumination.
