an upper substrate and a lower substrate assembled to form a cell with a gap between the upper substrate and the lower substrate, the gap being configured to accommodate a droplet;

a driving electrode on an upper substrate side or a lower substrate side,

wherein the micro-fluidic chip further comprises a laser source on the upper substrate side and configured to provide illumination for detection of the droplet,

a first planarization layer is further on a side of the upper substrate on which the laser source is disposed, a via hole is in the first planarization layer, a bottom electrode is on the upper substrate at a bottom of the via hole, and a top electrode is on two opposite sides of an edge of a top opening of the via hole;

a part of the laser source is in the via hole, the laser source comprises a first electrode and a second electrode, the first electrode is coupled to the bottom electrode, the second electrode is coupled to the top electrode, and the bottom electrode and the top electrode are respectively coupled to an output terminal of a power supply to provide power to the laser source;

a second planarization layer is further on a side of the laser source away from the first planarization layer, and a first hydrophobic layer is on a side of the second planarization layer away from the laser source and is configured to contact with the droplet; and

the laser source comprises a vertical cavity surface-emitting laser.