Dalsa 1M28-SA User Manual

Contents

Dalsa 1M28-SA User Manual Manual pdf 31 page image

1M28, 1M75, and 1M150 User’s Manual PRELIMINARY 31DALSA 03-32-00525-04Figure 21: Free Running Mode, Constant Image Data RateFrame TimerIntegration Readout IntegrationResetFigure 22: Free Running Mode, Variable Image Data RateIntegration Readout Integration ReadoutGlobal Shutter TimingWith a global shutter, the sensor starts with a global reset of all pixels. Then during the integrationtime, photo-generated electrons are collected in the pixels. After the exposure time, the collectedelectrons are transferred to a storage node, and sequential readout of the sensor matrix begins. As aresult, all pixels are exposed to light for the same amount of time, resulting in crisp images that donot suffer from the time displacement artefacts characteristic of rolling shutter CMOS cameras.Figure 23: Global Shutter TimingResetDataGlobal shutterReset Integration Frame ReadoutFreerunning ModeThe freerunning mode is the factory set timing mode at power up and captures images without theneed for an external control signal. The sensor data is read out after the set integration time. Afterthe sensor is finished reading out, the sensor resets and the sequence begins again. The data isoutput 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).