Dana L Anderson

US Patent:

42478324, Jan 27, 1981

Filed:

Dec 26, 1978

Appl. No.:

5/973096

Inventors:

Virgil E. Sanders - Newbury Park CA
Dana Z. Anderson - Tucson AZ

Assignee:

Litton Systems, Inc. - Beverly Hills CA

International Classification:

H01S 3101

US Classification:

331 945C

Abstract:

A nonplanar ring laser for use as a laser gyro includes an even number of at least six reflecting surfaces which are preferably all made from the same coating batch or coating run so that they have substantially the same anisotropy characteristics. The mirrors are divided into pairs of mirrors, and the mirrors in at least each pair must match in their anisotropic characteristics. Note that the matched mirrors need only be in the laser path but not necessarily adjacent. The nonplanar geometric arrangement of the reflecting surfaces is such that the reflecting plane of incidence of each mirror is at substantially a right angle to the reflecting plane of incidence of at least one of the adjacent mirrors in the laser path. Note that the reflecting plane of incidence of each mirror may optionally be at right angles to the reflecting planes of incidence of both its adjacent mirrors in the laser path. The angles of incidence of the mirrors in each matched pair must be substantially the same.

US Patent:

56128126, Mar 18, 1997

Filed:

Aug 31, 1995

Appl. No.:

8/521680

Inventors:

Gan Zhou - Pasadena CA
Dana Z. Anderson - Boulder CO

Assignee:

The United States of America as represented by the Secretary of the Air
Force - Washington DC

International Classification:

G02F 103
G03H 110

US Classification:

359244

Abstract:

A photorefractive pirouette display device can produce the sonogram of speech sounds by incorporating the short-time Fourier spectrum of speech waves as the input. The device requires a coherent source of optical radiation which can be obtained for a variety of different lasers. A photorefractive circuit is used to display a time-dependent signal, beam. An analog signal is imposed on the beam as temporal modulations on its intensity and/or phase, the pump beam is a plane wave constant amplitude. The signal beam interferes with the pump beam in the photorefractive crystal, the resultant intensity modulation pattern nonuniformly excites the charge carriers in the crystal. The excited charge carrier migrate in the crystal to form a microscope electric field, which produces an index grating in the crystal due to the Pockels effect. The crystal is rotating continually with angular velocity. The pump beam diffracts off of the holographic grating and reconstructs the signal beam.

US Patent:

45710856, Feb 18, 1986

Filed:

Oct 11, 1983

Appl. No.:

6/540788

Inventors:

Dana Z. Anderson - Pasadena CA

Assignee:

California Institute of Technology - Pasadena CA

International Classification:

G01N 2155

US Classification:

356445

Abstract:

A method and apparatus for making decay time measurements of an optical cavity having at least two reflecting optical elements by directing a beam of light into the cavity, switching the beam of light off when the intensity in the cavity reaches a predetermined threshold level, monitoring the beam intensity decay of the optical cavity, and measuring the intensity decay time either with a storage oscilloscope or a digital counter.