Manufacture Of Optical Glass Research Articles

Optical Glass

THE earliest lenses-those made by Galileo and men of his time were made of glass, not optical glass in particular, but any glass; -the glass available. In other words, in early times there was no such thing as optical glass as we now understand the term. As time went on and the demand for better lenses and a greater variety of the same increased, greater attention and more careful calculations were brought into play. It became evident, as was demonstrated by Dr. Abbe in the early 80's, that the then existing varieties of glass were not sufficient either in quality or diversified properties to meet the needs. About this time both in France and Germany some real research was begun in the manufacture of optical glass as we now know it. Problems not only in making a greater variety of glasses but in eliminating defects in the kinds already made were pressing for solution. Indeed, some of these problems are only recently being solved. This is particularly true in regard to annealing, for we find that our own glass is much better annealed than that of foreign makers who have been working at the problem for years. We have given considerable attention to the annealing and have adopted some really scientific methods which have brought very satisfactory results.

The manufacture of optical glass

The manufacture of optical glass

PROCEDURES IN THE MANUFACTURE OF OPTICAL GLASS

Journal of the American Ceramic SocietyVolume 2, Issue 6 p. 422-442 PROCEDURES IN THE MANUFACTURE OF OPTICAL GLASS W. S. Williams, W. S. Williams Bureau of Standards, Pittsburgh, Pa.Search for more papers by this authorC. C. Rand, C. C. Rand Bureau of Standards, Pittsburgh, Pa. By permission of the Director, Bureau of Standards.Search for more papers by this author W. S. Williams, W. S. Williams Bureau of Standards, Pittsburgh, Pa.Search for more papers by this authorC. C. Rand, C. C. Rand Bureau of Standards, Pittsburgh, Pa. By permission of the Director, Bureau of Standards.Search for more papers by this author First published: June 1919 https://doi.org/10.1111/j.1151-2916.1919.tb17526.xCitations: 1 Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume2, Issue6June 1919Pages 422-442 RelatedInformation

Optical Glass

ONE of the surprises of the great war has been the revelation to the majority of people of the extent to which a nation may be absolutely odependent for the conduct of the war on an industry which, in its magnitude, may seem quite insignificant, but, owing to the technical experience underlying it, cannot be acquired in a short space of time. In the forefront of such vital industries is the manufacture of optical glass. However great the other resources in men and material may be, it would be quite impossible to wage successful warfare without adequate supplies of optical glass ior binocular field-glasses, range-finders, artillery osights, photographic lenses for aircraft, etc. It is of interest to trace briefly the history and practice of this important “key” industry, and to consider how the nation will be situated as regards the supply of optical glass when peace is restored and it will again be in competition with German glass.

OPTICAL GLASS MANUFACTURE IN AMERICA

School Science and MathematicsVolume 19, Issue 2 p. 181-185 OPTICAL GLASS MANUFACTURE IN AMERICA L. M. Potter, L. M. Potter Secretary Spencer Lens Company.Search for more papers by this author L. M. Potter, L. M. Potter Secretary Spencer Lens Company.Search for more papers by this author First published: February 1919 https://doi.org/10.1111/j.1949-8594.1919.tb14007.xAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Volume19, Issue2February 1919Pages 181-185 RelatedInformation

AN IMPROVED METHOD OF OPTICAL GLASS MANUFACTURE

AN IMPROVED METHOD OF OPTICAL GLASS MANUFACTURE

The Manufacture of Optical Glass in America

The Manufacture of Optical Glass in America

The Manufacture of Optical Glass in America

The Manufacture of Optical Glass in America

Annealing Glass

EVERYONE who makes chemical apparatus by blowing glass practises annealing in a rude way. by allowing the glass to cool slowly by g actual removal from the flame, or by the use of a smoky flame. In glass works more systematic annealing is effected by slow passage through a long chamber wherein the temperature falls from the incoming to the outgoing end. In the manufacture of optical glass of many different qualities the question of annealing is one of the first importance, as they differ so much in fusibility. Messrs. Hilger have after a careful investigation found the means of arriving at the maximum temperature necessary, and also the necessary rate of cooling, which may progressively become more rapid. Optical glasses may differ as much as 200° C. in the maximum necessary temperature, which temperature may be a long way below any visible softening point. It is desirable not to exceed the necessary temperature, as the very slow cooling at the higher temperature leads to great loss of time.

Stretchers of Straw for the Dutch Army, Manufacture of Optical Glass in America, and more

Stretchers of Straw for the Dutch Army, Manufacture of Optical Glass in America, and more

I. Appendix to the description of the great Melbourne telescope

Since this paper was read the author has made several observations of the quantity of light transmitted by object-glasses, and determined the index of absorption in various specimens of glass. The results of some of these are in accordance with the opinion expressed in the paper; but others present a difference which is very satisfactory as indicating a sur­prising progress in the manufacture of optical glass. The observations were made by means of Zollner’s photometer. The following results were obtained for the intensity of the light trans­mitted by a variety of object-glasses :— Of the above, a belongs to the Armagh Observatory; it is by one of the Dollonds, older than 1790, and is probably one of their first attempts at a triple combination, b is the original object-glass of the Armagh circle; it was made by Tulley about 1828 ; the crown is greenish, and is supposed to be English; the flint is believed to have been from Daguet. c was made for the author by Tulley in 1838; its glass is French, the crown is greenish, d is by Cauchoix; the crown is greenish, and has probably a high n , but its mean thickness is only 0.39. e is by Messrs. Cooke; the glass is Chance’s, f is by Grubb, the glass Chance’s: the very high trans­mission of this lens is in part due to the cementing of the adjacent sur­faces, which, while it makes more difficult the correction of spherical aberration, removes almost entirely the reflection at a surface of crown and one of flint: the factor for this =0.9036; and if the I be multiplied by this, we obtain 0.7806, nearly that of e , the difference being due to the reflection at the film of cement, g is also by Grubb, and cemented; the glass is by Chance, h is by Fraunhofer.

On the Manufacture of Optical Glass in England

On the Manufacture of Optical Glass in England

Suggestions for improving the manufacture of optical glass

Suggestions for improving the manufacture of optical glass

Suggestions for Improving the Manufacture of Optical Glass

Suggestions for Improving the Manufacture of Optical Glass