FIELD

Embodiments described herein relate generally to an optical test apparatus and an optical test method.

BACKGROUND

In various industries, contactless test techniques have become important. There are conventional contactless test apparatuses designed to measure spatial fields by using schlieren methods.

The conventional schlieren methods can discriminate the presence/absence of a refractive index distribution or scattering but have difficulty in quantitatively measuring the magnitude of a refractive index or scattering. Under the circumstance, a technique using a color opening is available as a quantitative measurement method.

