@article{oai:niigata-u.repo.nii.ac.jp:00001537,
 author = {Dai, Xiaoli and Sasaki, Osami and Greivenkamp, John E. and Suzuki, Takamasa},
 issue = {28},
 journal = {Applied Optics, Applied Optics},
 month = {Oct},
 note = {Based on measuring one-dimensional small rotation angles by using a parallel interference pattern (PIP), a method lor measuring two-dimensional (2D) small rotation angles by using two different PIP's that are orthogonal to each other is proposed. We simultaneously measure the 2D small rotation angles Δθ and ΔΦ by detecting the phases of the orthogonal PIP's reflected by an object at two detection points. A sensitivity of4.9 mrad/arcsec and a spatial resolution of 1.5 × 1.5 mm^2 are achieved in the measurement. Theoretical analysis and experimental results show that errorε1 in the measurement of ΔΦ is almost equal to -0.01Δθ and errore ε2 in the measuremcnt of Δθis almost equal to -0.01A ΔΦ. For small rotation angles of less than a few tens of arcseconds, the random errors whose standard deviations are 0.6 arcsec are dominant.},
 pages = {5657--5666},
 title = {Measurement of two-dimensional small rotation angles by using orthogonal parallel interference patterns},
 volume = {35},
 year = {1996}
}