MEASURING APPARATUS OF SLANT ANGLE FOR SOLID IMMERSION LENS

摘要

PURPOSE: A measuring apparatus for a slant angle of a SIL(Solid Immersion Lens) is provided to prevent a focal signal from generating error by measuring a slant degree of the SIL quantitatively with a principle of a collimator. CONSTITUTION: A measuring apparatus for a slant angle of a SIL(Solid Immersion Lens,211) comprises a light generating device(201), a first condenser(203) and a position sensing device(210). The light generating device generates light when projecting to the SIL formed like a hemisphere. The first condenser collects light reflected from a specular surface(208) on a lower portion of the SIL. The position sensing device measures a slant of the SIL according to a focus collected by the first condenser. A light divider(202) is included to project light generated from the light generating device to the first condenser and to progress light horizontally inside the SIL. Therefore, the focus of the SIL is formed correctly by measuring the slant of the SIL and compensating the slant with measured value.