Freerunning Mode - Dalsa 1M28-SA User Manual

1M28, 1M75, and 1M150 User's Manual
Figure 21: Free Running Mode, Constant Image Data Rate
Integration
Figure 22: Free Running Mode, Variable Image Data Rate
Integration
Global Shutter Timing
With a global shutter, the sensor starts with a global reset of all pixels. Then during the integration
time, photo-generated electrons are collected in the pixels. After the exposure time, the collected
electrons are transferred to a storage node, and sequential readout of the sensor matrix begins. As a
result, all pixels are exposed to light for the same amount of time, resulting in crisp images that do
not suffer from the time displacement artefacts characteristic of rolling shutter CMOS cameras.
Figure 23: Global Shutter Timing
Data
Global shutter
Reset

Freerunning Mode

The freerunning mode is the factory set timing mode at power up and captures images without the
need for an external control signal. The sensor data is read out after the set integration time. After
the sensor is finished reading out, the sensor resets and the sequence begins again. The data is
output on the rising edge of the pixel clock.
The signals FRAME_VALID (FVAL) and LINE_VALID (LVAL) mask valid image information.
The number of clock pixels after exposure CPRE is defined by the calculation of the frame time
(see section 1.12 Calculating Frame Rate).
DALSA
PRELIMINARY
Readout
Frame Timer
Readout
Reset Integration
Reset Integration
Integration
Frame Readout
31
Readout
03-32-00525-04