Optical Shop Testing

Chapter 5 - Radial, Rotational, and Reversal Shear Interferometer

5.1.   INTRODUCTION

The two interfering wavefronts in a two beam interferometer can have several
possible relative orientations and sizes with many different configurations. As
pointed out by Steel (1983) and by Walmsley and Malacara (1995), the first order
properties of these two beam interferometers can be completely described by

  1. the light source position and the location, orientation, and size of the two
    images of this light source as seen from the observation plane;
  2. the image plane position and the location, orientation, and size of the two
    images of this observation screen as seen from the light source position; and
  3. the optical path difference between the two optical paths.

These parameters completely define the lateral shear, tilt, and lead. The shear is
the relative lateral displacement of the two interfering wavefronts and shift is their
longitudinal separation. The tilt is the lateral separation of the two images of the light
source and the lead is their longitudinal separation. A fifth independent parameter is
the optical path difference (OPD), which is a function of the traversed refractive
indices. These parameters are illustrated in Figure 5.1. The main properties of all
shearing interferometers can be analyzed by these parameters.

Although the most popular shearing interferometer is the lateral shearing instrument,
other types are equally useful. In this chapter we examine radial, rotational,
and reversal shear interferometers, whose basic wavefront operations are illustrated
in Figure 5.2. Many review papers (Murty, 1967; Briers, 1972; Fouere and Malacara,
1975) and books (Bryngdahl, 1965; Steel, 1966; Baird and Hanes, 1967) have very
good general descriptions of them. The radial shear interferometer produces two
interfering wavefronts with identical deformations, but one of the wavefronts is
contracted or expanded with respect to the other.

UNLIMITED FREE
ACCESS
TO THE WORLD'S BEST IDEAS

SUBMIT
Already a GlobalSpec user? Log in.

This is embarrasing...

An error occurred while processing the form. Please try again in a few minutes.

Customize Your GlobalSpec Experience

Category: Optical Prisms
Finish!
Privacy Policy

This is embarrasing...

An error occurred while processing the form. Please try again in a few minutes.