Notes on Triggering
Definitions
oUser Trigger is the trigger signal applied by the user.
oLogic Trigger is the trigger signal seen by the camera internal logic.
oTpd is the propagation delay between the User Trigger and the Logic Trigger.
oExposure is high when the camera image sensor is integrating light.
oReadout is high when the camera image sensor is reading out data.
oTrigger Latency is the time delay between the User Trigger and the start of Exposure.
oTrigger Jitter is the error in the Trigger Latency time.
oTrigger Ready indicates to the user that the camera will accept the next trigger.
oRegistered Exposure Time is the Exposure Time value currently stored in the camera memory.
oExpose Start Delay is the delay time from the start of Exposure to valid Trigger Ready. It is the Registered Exposure Time subtracted from the Readout time and indicates when the next Exposure cycle can begin such that the Exposure will end after the current Readout.
oInterline Time is the time between sensor row readout cycles.
oImaging is high when the camera image sensor is either exposing and/or reading out data.
oIdle is high if the camera image sensor is not exposing and/or reading out data.
Rules
oThe User Trigger pulse width should be at least three times the width of the Trigger Latency as indicated in the Specifications section of this document.
oThe end of Exposure will always trigger the next Readout.
oThe end of Exposure must always end after the current Readout.
oThe start of Exposure must always correspond with the Interline Time if Readout is true.
oExpose Start Delay equals the Readout time minus the Registered Exposure Time.
Triggering during the Idle State
oFor applications requiring the shortest possible Trigger Latency and the smallest possible Trigger Jitter the User Trigger signal should be applied when Imaging is false and Idle is true.
oIn this case, Trigger Latency and Trigger Jitter are as indicated in the Specifications section.
GX3300 Technical Manual | Page 33 |