A phase-contrast refractometer for measurements in the infrared has been constructed. The optical and mechanical arrangement is discussed and a brief description of the experimental procedure is given. A value for (n−1) of air of 0.00026834 was obtained for the 1.014-μ line of mercury. The standard deviation of the mean is ±0.7%.
© 1958 Optical Society of AmericaFull Article | PDF Article