Dalsa Pantera TF 11M4, Руководство пользователя

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Pantera TF 11M and 6M User’s Manual Preliminary 41
DALSA 03-32-10096-03
5
Cleaning and
Maintenance
5.1 Cleaning
Electrostatic Discharge and the CCD Sensor
Charge-coupled device (CCD) image sensors are metal oxide semiconductor (MOS)
devices and are susceptible to damage from electrostatic discharge (ESD). Although many
sensor pins have ESD protection circuitry, the ESD protection circuitry in CCDs is
typically not as effective as those found in standard CMOS circuits.
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. When charge buildup occurs, surface gated photodiodes
(SGPDs) may exhibit higher image lag. Some SGPD sensors may also exhibit a highly
non-uniform response when affected by charge build-up, with some pixels displaying a
much higher response when the sensor is exposed to uniform illumination. The charge
normally dissipates within 24 hours and the sensor returns to normal operation.
Preventing ESD Damage
To prevent ESD damage, DALSA advises you to take the following handling precautions.
1.
Ground yourself prior to handling CCDs.
2. Ensure that your ground and your workbench are also properly grounded. Install
conductive mats if your ground or workbench is non-conductive.
3. Use bare hands or non-chargeable cotton gloves to handle CCDs. NOTE: Rubber
fingercots can introduce electrostatic charge if the rubber comes in contact with the
sensor window.
4. Handle the CCD from the edge of the ceramic package and avoid touching the sensor
pins.
5. Do not touch the window, especially in the region over the imaging area.