Dalsa Falcon 1.4M100 HG Monochrome, User Manual

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DALSA Falcon XDR and HG Series Camera User's Manual
36 Serial Interface: How to Control the Camera
3.7 Setting Exposure Mode, Frame Rate and
Exposure Time
3.7.1 Non-Concurrent vs. Concurrent Modes of Operation
One of the main benefits of DALSA’s global shutter CMOS devices is that you have the choice to operate
the camera where integration and readout are concurrent (that is, they overlap for some duration) or
where integration and readout are not concurrent (that is, they occur serially). Integration is defined as the
time period that the camera can be exposed to light and is often referred to as exposure time. Readout
refers to the time it takes to read out every pixel from the camera. For a 100 fps camera, such as the
Falcon 1.4M100, the readout period is around 10.0ms.
Thus, a global shutter CMOS device, as found in the 1.4M100, is capable of running at 100fps with
exposure times up to 10ms. Beyond 10ms, the exposure time exceeds the readout time and the frame
rate drops. With rolling shutter CMOS devices only non-concurrent modes are possible and the
integration time immediately impacts the frame rate, thus comparable 1.4 megapixel cameras with a
10ms exposure time would only run at 50fps.
Concurrent mode is when the camera is integrating the current frame (Frame 1) and at the same time is
reading out the prior frame (Frame 0). By performing integration and readout in parallel, the Falcon
1.4M100 camera is capable of reaching 100fps even with exposure times up to 10ms. A timing diagram
helps to explain this mode of operation.
Concurrent Mode Timing Diagram
In concurrent mode, a low-to-high transition in the EXSYNC signal starts the integration time, and a high-
to-low transition in the EXSYNC signal starts the readout of image data. As your frame period
approaches the readout period, by reducing the Waiting time, the Falcon 1.4M100 camera approaches its
maximum frame rate of 100fps.
In non-concurrent mode the integration and readout period do not overlap
Non-concurrent Mode Timing Diagram