Dalsa Pantera DS-21-01M60, Руководство пользователя и справочник

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Pantera 1M60 and 1M30 User’s Manual 37
DALSA 03-032-10033-09
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 cameras.
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 cameras. NOTE: Rubber
fingercots can introduce electrostatic charge if the rubber comes in contact with the
sensor window.
4. Do not touch the window, especially in the region over the imaging area.
5. Ground all tools and mechanical components that come in contact with the cameras.
6. DALSA recommends that cameras be handled under ionized air to prevent static
charge buildup.
The above ESD precautions need to be followed at all times. The rate which
electrostatic charge dissipates depends on numerous environmental conditions and