Abstract

A Comparator Microphotometer of new design is described. An optical system has been developed in which all of the available light flux is used for both viewing the spectrum and measuring the transmission of selected spectral lines. Besides high viewing screen intensity and great sensitivity, a unique electronic system is employed. The advantages of this null-ratio system include: reduced drift and noise, independence of individual vacuum tube characteristics, and freedom from the logarithmic damping response characteristic of galvanometers and meters.

© 1957 Optical Society of America

Ratio-Recording System for the Johns Hopkins 100-Foot Absorption Cell*

C. Harvey Palmer
J. Opt. Soc. Am. 47(5) 367-377 (1957)

Automatic Recording Reflectometer for Measuring Diffuse Reflectance in the Visible and Infrared Regions

Willard L. Derksen, Thomas I. Monahan, and Alfred J. Lawes
J. Opt. Soc. Am. 47(11) 995-999 (1957)

New Principle for Focusing a High-Power Microscope and Means for Accomplishing the Focusing Automatically and with Great Accuracy*

L. Baxter, J. DeYoung, R. C. C. St. George, and W. A. Shurcliff
J. Opt. Soc. Am. 47(1) 76-80 (1957)

Photographic Granularity and Graininess. IX. Techniques and Equipment for the Objective Measurement of Graininess*

L. A. Jones, G. C. Higgins, K. F. Stultz, and H. F. Hoesterey
J. Opt. Soc. Am. 47(4) 312-321 (1957)

Bilayer Bichromatic Cathode Screen

Charles Feldman
J. Opt. Soc. Am. 47(9) 790-794 (1957)