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Genie Monochrome Series-GigE Vision Camera 
Technical Specifications    95 
Example: An acquisition system has a 512 x 512 element, 10
μm pixel pitch area scan camera, a lens with an 
effective focal length of 45mm, and requires that 100
μm in the object space correspond to each pixel in the image 
sensor. Using the preceding equation, the object distance must be 450mm (0.450m). 
 
OD
mm
m
m
45
100
10
=
μ
μ
 
)
450
.
0
(
450
m
mm
OD
=
 
 
Sensor Handling Instructions 
This section reviews proper procedures for handling, cleaning, or storing the Genie camera. Specifically the Genie 
CCD sensor needs to be kept clean and away from static discharge to maintain design performance.  
Electrostatic Discharge and the CCD Sensor 
Cameras contain charge-coupled device (CCD) image sensors, which are metal oxide semiconductor (MOS) devices 
and 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. When charge buildup 
occurs, surface-gated photodiodes (SGPDs) may exhibit higher image lag or a highly non-uniform response, 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.  
 
 
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 CCD 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.  
Scratches can be caused by improper handling, cleaning or storage of the camera. When handling or storing the 
Genie camera without a lens, always install the C-mount 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.