Page:Journal of the Optical Society of America, volume 30, number 12.pdf/76

 DECEMBER, 1940

was particularly appropriate that the twenty-fifth annual meeting should have been held in Rochester, the birthplace of the Society. For several years before the founding of the Optical Society of America in 1916, a local group of optical experts had been organized, and the national society grew out of this organization. During the process, the local group maintained its identity and is known today as the Rochester Section. The enthusiastic efforts of the local committee appointed by the Rochester section were largely responsible for making this meeting one of the most successful in the history of the Society.

The meeting was opened Thursday, October 3, at 9:30 by President Gibson with a session of contributed papers.

A lecture and demonstration of practical uses of the academically familiar phenomena of polarization by Mr. Edwin H. Land delighted those who knew what to expect as much as those who really preferred to believe in magic. For the latter, a sheet of ordinary-looking celluloid held in the hand could be black, white, red, or green at Mr. Land’s whim. At the same time and in the same place could be seen a picture of the Taj Mahal or the kitchen sink depending upon the manner of holding the sheet material before the eyes.

For the more technically minded, the importance of this demonstration resided in the fact that only one projection lantern was used. This is made possible by controlling the degree of polarization of a polarizing surface in which the pictures are formed. A transparent sheet composed of oriented molecules of a long chain polymer is brought into contact with a solution containing a component which, when combined with the original molecule, produces a polarizing molecule. By controlling the number of these polarizing molecules, it is possible to achieve any desired degree of contrast in an image in terms of polarization if the image is viewed through a polarizing material. The advantages of projecting three-dimensional pictures by means of a single lantern are many. This was admirably demonstrated by a series of stereoscopic pictures representing subjects of all types. The demonstration closed with a stereoscopic picture projected in full color by means of a single lantern.

If for no other reason, the Rochester meeting would be memorable for its group of invited papers. These were presented by authors who combined unquestioned knowledge of their fields with the happy faculty of discussing, their subjects in an extremely lucid manner. The program of these papers was as follows:

1. A Quarter Century of Optics Reviewed,, Bell Telephone Laboratories.

2. Quality Control in the Manufacture of Optical Instruments—Twenty-Five Years’ Progress,, Bausch & Lomb Optical Company.

3. Recent Developments in Photography, }, Eastman Kodak Company.

4. Producing Low Reflecting Glass,, Corning Glass Works.

Dr. Ives began by describing the transformation undergone by the concept of radiation from the time of Newton to the present. His discussion fascinated the imagination of the theorists as completely as it did those who think of radio as something to hear with and light as something to see with. In a most entertaining manner, he described the upset of the well-ordered wave theory after the discovery of the photoelectric effect and the resulting transformation of the subject into a paradise for the mathematician.

Physiological optics was represented by the speaker as a subject of slow and labored progress, which is still open to further chemical and physical interpretation. Helmholtz’ theory of the visual purple and the theory of the visual violet, although attacked through a “clam’s eye view,” have been extended to the vertebrates. An inter