For optical device, pad and emitting area may be designed at the top of die surface or designed at the opposite surface of die. Corresponding to the design, MPI’s prober can be separated into top probing system, bottom probing system and single die testing system. For top probing system, MPI prober provides high accurate table, soft needle contact and great optical measurement structure. For bottom probing system MPI prober provides rigid moving table, flexible material handling methods and most accurate optical measurement solution. For single die testing system, MPI prober provides optical device testing under full flux environment. Three major measurement structures apply in varies optical device requirement. MPI prober will provide these requirement with efficiently and accurate solution.