Abstract

Details are given of a technique for measuring the reflectance at near-normal incidence of small, irregular, submillimeter-sized samples from the far IR (40 cm−1) to the visible (40000 cm−1) between 10 and 300 K by using a modified Michelson interferometer or grating spectrometer. The sample and a reference mirror are mounted on nonreflecting cones. At the focus the size of the beam is larger than either the sample or the reference, so that the entire area of the sample is utilized. The positions are interchanged by a 90° rotation by using preset mechanical stops. The scattering caused by geometrical effects is corrected for by the in situ evaporation of gold or aluminum onto the sample. The effect of diffraction is estimated from Mie theory by assuming the sample and reference to be spheres. For frequencies above ≈ 40 cm−1 and sample diameters of ≈ 1 mm with a detector field of view of 30°, the calculations show that the ratio of the backscattered intensities gives a good approximation of the specular reflectance.

© 1993 Optical Society of America

Full Article  |  PDF Article
OSA Recommended Articles
Vacuum deposition of iridium on large astronomical mirrors for use in the far UV

Howard Herzig and Rodney S. Spencer
Appl. Opt. 21(1) 15_1-16 (1982)

Monitoring the Thickness of Thin MgF2 and LiF Films on Al by Reflectance Measurements Using the 1216-Å Line of Hydrogen

E. T. Hutcheson, J. T. Cox, G. Hass, and W. R. Hunter
Appl. Opt. 11(7) 1590-1593 (1972)

Preparation of Mirror Coatings for the Vacuum Ultraviolet in a 2-m Evaporator

A. P. Bradford, G. Hass, J. F. Osantowski, and A. R. Toft
Appl. Opt. 8(6) 1183-1189 (1969)

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Figures (8)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Tables (1)

You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Equations (1)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Metrics

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription