A flow-cytometer has an excitation light source generating an excitation light that excites one or more bio-cells in a bio-sample carried by a flow path to luminesce. The flow-cytometer includes a spectrum dispersive element that disperses the luminescent light generated by the bio-sample into a photo-detector array. The flow-cytometer further includes a digital signal processor (DSP) that receives signals from the photo-detector array and generates a self-triggering signal based on the luminescent light generated by the bio-cells in bio-sample. The self-triggering signal triggers data capture in the DSP to improve synchronization with the data generated from signals received from the photo-detector array.