Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group

The Ruling of Diffraction Gratings at the Mount Wilson Observatory

Not Accessible

Your library or personal account may give you access

Abstract

The newer ruling engine of the Mount Wilson Observatory is now producing sizable diffraction gratings of high quality in all respects. Several recent gratings are 714 inches wide with grooves 534 inches long, and one is 8 by 514 inches. Curved-edge ruling diamonds, developed here, have been used in blazing these gratings to specifications for astronomical use. High luminous efficiency is combined with practically complete absence of scattered light, either general or local, in the spectrum. Resolving power of 500,000 is achieved. Rowland ghost intensity is held to about 0.00004 in the first order of 15,000 line per inch rulings. Most ruling to date has been at 300, 400, 600, or 900 grooves per millimeter, but other spacings are available. The rather considerable modifications of the Rowland-type engine are described, with particular reference to the monorail diamond carriage, the coupling of the nut to the grating carriage, the end-thrust bearing of the screw, the use of Nitralloy steel ways, and the spacing mechanism.

That the principles of this entirely mechanical, single-screw machine are thoroughly sound is attested by the quality of its products. Blazed plane gratings have almost entirely supplanted prisms in fast stellar spectrographs of both short and long focus.

Our methods of testing gratings are outlined and a formula is proposed for the evaluation of gratings.

© 1951 Optical Society of America

Full Article  |  PDF Article
More Like This
The Production of Diffraction GratingsI. Development of the Ruling Art*

George R. Harrison
J. Opt. Soc. Am. 39(6) 413-426 (1949)

New Johns Hopkins Ruling Engine*

John Strong
J. Opt. Soc. Am. 41(1) 3-15 (1951)

750-mm Ruling Engine Producing Large Gratings and Echelles*

George R. Harrison, Stephen W. Thompson, Harry Kazukonis, and Joseph R. Connell
J. Opt. Soc. Am. 62(6) 751-756 (1972)

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 Optica member, or as an authorized user of your institution.

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

Figures (9)

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

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

Equations (3)

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

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

Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All Rights Reserved