| 摘要 |
Method and apparatus are herein disclosed for exposing a recording plane to a stable interferometric line pattern where the recording plane extends beyond the boundary of the exposure pattern. A beam of highly coherent collimated light is split into at least two beams of light and the beams recombined in the recording plane to create an interference pattern of light and dark fringes. At least one flat glass plate is obliquely repositionable in the unsplit light beam and serves to shift the position of the light beam whereby the beam of light leaving the plate is substantially parallel to the light beam entering the plate. This, in effect, causes the illuminated region in the recording plane to be shifted to a new location in the plane without altering the phase relationship of the individual interference fringes. Thus, each bright fringe remains in a stationary position and only changes in intensity as the exposure pattern is moved in the recording plane.
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