Computerized refractive index measurements for bulk materials at UV, visible, and IR wavelengths

摘要: A computer‐controlled apparatus was built to measure refractive index and its temperture coefficient fifth decimal place accuracy at UV, visible, IR wavelengths. Deviation of monochromatic radiation through a prism having reflecting rear surface is measured by the autocollimation method as in Littrow spectrometer. Entrance exit rays are superimposed, so that fixed entrance/exit port permits convenient temperature‐controlled enclosures for measurement dn/dT. Angle measurments involve only rotation prism, making use 20‐bit digital angle sensor suitable computer readout. geared stepping‐motor drive control data acquisition processing. Useful wavelength coverage has far included range from 0.25 8 μm, but limited source intensity, detector senstivity, sample transparency. Index results four germano–silicate glasses 22 wavelengths between 0.36 1.69μm reported values dn/dT pur...