US Patent 10410893 Micro elements transfer device and method

A transfer device for micro element with a test circuit can test the micro element during transfer. The transfer device for micro elements includes: a base substrate, having two surfaces opposite to each other; a pick-up head array, formed over the first surface of the base substrate for picking up or releasing the micro element; a test circuit set inside or/on the surface of the base substrate, which has a series of sub-test circuits, each sub-test circuit at least having two test electrodes for simultaneous test of photoelectric parameters of the micro element when the transfer device transfers the micro element.