US Patent 11480742 Micro device mass transfer tool

A micro device transfer tool and methods of operation are described. In an embodiment, the micro device transfer tool includes an articulating transfer head assembly capable of six degrees of motion. A miniatured camera assembly may be secured near the point of contact for the articulating transfer head assembly to aid in system alignment. In an embodiment, an encoder system is described for alignment of a micro pick up array and target substrate using complementary concentric grating patterns. In an embodiment a miniaturized position sensor design is described for sensing position of various system components during alignment or pick and place processes.