An image flow cytometer for observing a microparticulate sample includes a flow chamber having a flow channel that permits the microparticulate sample to travel in a flow direction. An irradiation system scans an irradiation spot across a sensing area of the flow channel in a scan direction different from the flow direction. A detection system detects resultant light from the sensing area and provides a detection signal. An alignment system alters a location of the sensing area with respect to the flow chamber. A control unit causes the irradiation system to scan the irradiation spot during a first measurement interval and operates the alignment system to translate the location of the sensing area along the flow direction. The flow chamber can be mounted to a movable stage in some examples, and the alignment system can move the flow chamber substantially opposite the flow direction using the stage.