傾斜照明によるくりかえし型顕微干渉法

抄録

Double fringes are obtained by employing the oblique incidence to the multiple-beam interference system and are observed by a microscope in the light of the regular reflection.
The definition of the double fringes is weakened with increase of the oblique incident angle, but the distinct fringes are observed by polarized light in the plane of incidence.
The fringe spacing is accepted as the case of the two-beam oblique incidence type microinterferometer as equivalent to λ/2 cos θ. (λ is the wave length of the monochromatic light employed. θ is the angle of the incidence or the reflection.)
When the reflectance of the reference mirror employed is high, the fringe pattern may not show the accurate shape of the surface to be measured, so the reference mirror of low reflectance is to be used for the measurement of the surface roughness.