Gerald R Lange

US Patent:

48017981, Jan 31, 1989

Filed:

Dec 14, 1987

Appl. No.:

7/133112

Inventors:

Gerald R. Lange - Rochester NY

Assignee:

Eastman Kodak Company - Rochester NY

International Classification:

G01N 2121

US Classification:

250225

Abstract:

A method and apparatus for measuring optical retardation of a transparent material, such as the protective transparent cover sheet or substrate which protects the recording layer of an optical or magneto-optical disk. The method of the invention involves the steps of producing a beam of plane-polarized radiation in which the plane of polarization rotates continuously, directing such beam through a sample of transparent material where optical retardation is to be measured, and continuously comparing the angle of polarization of the beam entering the sample with the angle of plane polarization of the beam exiting the sample. Preferably, the beam and sample are continuously moved relative to another, whereby the optical retardation is measured at different points on the sample. The beam-producing step may be effected by passing a beam of circularly polarized radiation through a plane-polarizing filter while continuously rotating the filter. In this case, the comparing step may be achieved by (a) redirecting the beam exiting the sample back through the rotating filter and (b) monitoring the intensity of the beam after passing back through such filter.

US Patent:

42738520, Jun 16, 1981

Filed:

Dec 26, 1979

Appl. No.:

6/106643

Inventors:

Gerald A. Lange - Rochester NY
Charles J. Simpson - Rochester NY

Assignee:

Eastman Kodak Company - Rochester NY

International Classification:

G03C 554
G03D 900

US Classification:

430209

Abstract:

An instant film unit, including first and second superposed sheets, and conventional internal spacers for controlling the depth of a layer of processing fluid distributed by flowing the fluid between the sheets, is provided with additional internal spacers that reduce the resistance to fluid flow and augment the quantity of fluid supplied to the lateral edges of the imaging area. In the disclosure, the first spacers comprise portions of a mask, which frames the imaging area. The additional spacers are side rails which separate the lateral edges of the sheets by an amount greater than the thickness of the mask. The film unit is adapted for use with a processing device which includes a pressure nip long enough to span the imaging area, but the side rails are outside of the pressure nip adjacent the ends thereof.

US Patent:

54706262, Nov 28, 1995

Filed:

Feb 21, 1995

Appl. No.:

8/393142

Inventors:

James C. Fleming - Webster NY
Gerald R. Lange - Rochester NY
Donald R. Preuss - Rochester NY

Assignee:

Eastman Kodak Company - Rochester NY

International Classification:

B32B 300

US Classification:

428 648

Abstract:

An optical recording element comprising, in the following order, a transparent substrate bearing an optical recording layer containing a phthalocyanine dye and a gold reflective layer characterized in that the recording layer comprises sufficient sulfur or sulfur compound to prevent defects in the gold reflective layer.