Edge chip

A particle processing system comprising:

• a particle processing chip including:
• a substrate having a plurality of side surfaces, a top surface, and a bottom surface, the plurality of side surfaces defining a thickness of the substrate and the top surface and the bottom surface defining a width and a length of the substrate;
• and
• a microfluidic channel disposed in the substrate parallel to a first side surface of the plurality of side surfaces and located in the substrate relative to the first side surface to allow a maximal half-angle for a ray of light passing from a center of the microfluidic channel through the first side surface of between 25 degrees and 90 degrees;
• an electromagnetic radiation source to illuminate an interrogation region in the microfluidic channel through the bottom surface or the top surface of the substrate;
• a first detector to receive light from the microfluidic channel emitted through the top surface or the bottom surface of the substrate that is opposed to the electromagnetic radiation source;
• and
• a second detector to receive light from the microfluidic channel emitted through the first side surface of the substrate.