Eclipse EC-11-xxx40, User Manual

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EC-11 User’s Manual
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DALSA Corp. 03-32-00418-05
5. DC Offset needs to be set at calibrated gain setting. Digital gain correction may be
required to achieve maximum values.
Figure 2: EC-11 Spectral Responsivity
1.4 CCD Camera Primer
How CCD Image Sensors Work
A CCD image sensor converts photons (light) into electrons (charge). When photons hit
an image sensor, the sensor accumulates electrons. This is called charge integration. The
brighter your light source, the more photons available for the sensor to integrate, and the
smaller the amount of time required to collect a given amount of light energy.
The way photosensitive
elements (pixels) on CCD
image sensors collect
charge has often been
compared to wells or
buckets filling with
water. From this analogy
comes the term "full-well
capacity," meaning the
maximum charge (number of electrons) a pixel well can hold without "spilling" charge
onto adjacent pixels.
As an image sweeps over a line of pixels, the pixels collect charge. At certain intervals, the
sensor transfers its collected charge to one or more readout registers, which feed each
pixel’s charge from the image sensor into an output node that converts the charges into
voltages.
EC-11 Typical Spectral Responsivity
0
500
1000
1500
2000
2500
450 550 650 750 850 950 1050
Wavelength (nm)
Re
sp
on
siv
ity
D
N/(
nJ/c
m
²)