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to 240 frames per second.
Thus, sensors and cameras must be
able to accommodate higher frame
rates. CMOS cameras have improved
to a degree where they outper-form
traditional CCD-based imagers. A new
off-the-shelf 12-Megapixel digital image
sensor from CMOSIS, the CMV12000
Series, delivers 300 fps at full resolution
(10 bits per pixel). Other sensors of
the same product family show similar
data rates with different resolutions.
Even higher frame rates are feasible in
windowing or subsampling modes.
The same fast-paced progress of
CMOS sensors applies to pixel count,
or resolution. It has gone from 1.3
MP (SXGA) up to 2, 4, 8, 12 and 20
Megapixels. Higher resolution enables
cameras to capture more details that
can be analyzed within one image with
a wide field of view (Fig-ure 4). This
is advantageous in traffic management
applications, where one high-resolution
camera can now track up to four lanes
of traffic instead of having to deploy
four individual lane cameras.
In the light of this technological
progress, a resolution of 3.5 - 4K is
standard today in traffic and video
recording applications. For high-
end industrial inspection, as in flat-
panel inspection or aerial mapping,
standard resolution is 20 MP. However
this is not the end. The general trend
points to still higher resolutions for
global-shutter cameras. It might take
another year to get up to 40 - 50 MP.
This is where rolling-shutter sensors
are still defending their turf: with pixel
counts of up to 70 MP.
Demands on Image
Capture Systems
● High sensitivity: This should be
coupled with low noise levels as the
foremost consideration of industrial
users. High sensitivity will deliver
enough image data at short exposure
times. Low noise and high sensi-
tivity also allow operation at a low
light intensity by applying the proper
gain if needed. High sensitivity
across the visible spectrum should be
accompanied by increased sensitivity
in the near infrared.
● Low cost: Minimum system cost is
best achieved via image sensor size
reduction, optimization and if high-
volume production for yield
optimization.
● High frame rate: This enables
several shots of an object in a rapid-
fire sequence to track and document
its movements. This is supported by
the technique of exposing one image
while the previously taken im-age is
being read out.
● High resolution: This equals a large
field of view for delivering high image
Figure 3: Layout of the CSI2100 high-speed global-shutter
Figure 4: Capturing a large field of vision with great detail
40 l New-Tech Magazine Europe