Patent ID: 8508725

Claim:
A refractive index distribution measuring method comprising: a first measuring step of placing an object in a first medium having a first refractive index lower than a refractive index of the object, and of causing reference light to enter the object to measure a first transmitted wavefront of the object; a second measuring step of placing the object in a second medium having a second refractive index lower than the refractive index of the object and different from the first refractive index, and of causing the reference light to enter the object to measure a second transmitted wavefront of the object; a position measuring step of measuring a first placement position where the object is placed in the first medium and a second placement position where the object is placed in the second medium; and a calculating step of calculating an internal refractive index distribution of the object using the measured first and second transmitted wavefronts, wherein the calculating step calculates the internal refractive index distribution from which a shape component of the object is removed using (a) the measured results first and second transmitted wavefronts, (b) a first reference transmitted wavefront of a reference object to be placed in the first medium at a position identical to the first placement position and (c) a second reference transmitted wavefront of the reference object to be placed in the second medium at a position identical to the second placement position, the reference object having a shape identical to that of the object and a specific internal refractive index distribution.