Inventor
JEFFERS FREDERICK J
US42 patents
⚠️ This page may combine multiple inventors who share the name “JEFFERS FREDERICK J”. Patents are grouped by organization below to help distinguish them — per-person disambiguation is on the roadmap.
EASTMAN KODAK CO
31 patentsUS5418458AMay 23, 1995
Apparatus and method for authentication of documents printed with magnetic ink
EASTMAN KODAK CO146 citations98
US5260653ANov 9, 1993
Thin film very high sensitivity magnetoresistive magnetometer having temperature compensation and simple domain stability
EASTMAN KODAK CO75 citations96
US5119025AJun 2, 1992
High-sensitivity magnetorresistive magnetometer having laminated flux collectors defining an open-loop flux-conducting path
EASTMAN KODAK CO69 citations96
US4413296ANov 1, 1983
Thin film magnetoresistive head
EASTMAN KODAK CO56 citations96
US4992699AFeb 12, 1991
X-ray phosphor imaging screen and method of making same
EASTMAN KODAK CO34 citations93
US6372338B1Apr 16, 2002
Spherical magnetic particles for magnetic recording media
EASTMAN KODAK CO35 citations92
US5613712AMar 25, 1997
Magnetic fingerprint for secure document authentication
EASTMAN KODAK CO36 citations92
US5543911AAug 6, 1996
Method of currency or document validation by use of an anti-counterfeiting magnetic viewing strip
EASTMAN KODAK CO25 citations92
US5121258AJun 9, 1992
Apparatus for anhysteretic duplication of a flexible magnetic disk
EASTMAN KODAK CO37 citations92
US5552589ASep 3, 1996
Permanent magnet assembly with MR element for detection/authentication of magnetic documents
EASTMAN KODAK CO20 citations91
US5398145AMar 14, 1995
Tracking control apparatus including a servo head having a tapered transducing gap
EASTMAN KODAK CO35 citations87
US4683508AJul 28, 1987
Magneto-resistive head with reduced thermal noise
EASTMAN KODAK CO33 citations87
US5554932ASep 10, 1996
Measurement of a saturation magnetic flux density through use of a rotating permanent magnet
EASTMAN KODAK CO9 citations74
US5533759AJul 9, 1996
Method of currency or document validation by use of a temperature sensitive magnetic pattern
EASTMAN KODAK CO13 citations74
US5239435AAug 24, 1993
Laminated magnetic record/playback head with thin films of high permeability material spaced apart by very thin films of insulating magnetic material for high bit densities and data transfer rates
EASTMAN KODAK CO17 citations74
US4908724AMar 13, 1990
Dual gap cross-field magnetic recording head with single gap signal excitation
EASTMAN KODAK CO13 citations74
US4754354AJun 28, 1988
Ferrite film insulating layer in a yoke-type magneto-resistive head
EASTMAN KODAK CO13 citations74
US4633344ADec 30, 1986
Unambiguously tracking a data track in response to signals derived from the track data itself
EASTMAN KODAK CO16 citations74
US5353169AOct 4, 1994
Contact duplication of magnetically recorded information without the use of a transfer field
EASTMAN KODAK CO19 citations73
US5532584AJul 2, 1996
MR sensor including calibration circuit wherein signals are averaged for determining a correction factor and pole pieces are shaped to reduce field in gap therebetween
EASTMAN KODAK CO13 citations72
US3935578AJan 27, 1976
Thermo-magnetic image recording methods and apparatus
EASTMAN KODAK CO8 citations65
US5629620AMay 13, 1997
Apparatus and method for measurement of magnetic remanence-thickness product of thin magnetic layers
EASTMAN KODAK CO5 citations63
US5565772AOct 15, 1996
High sensitivity magnetic viewer using anhysteretic transfer for viewing weak magnetic patterns
EASTMAN KODAK CO5 citations63
US5218493AJun 8, 1993
Magnetic recording apparatus including a magnetic head having a curved media-contact surface equal to the curvature of a rotatable drum
EASTMAN KODAK CO4 citations63
US5025163AJun 18, 1991
Radiographic imaging screen
EASTMAN KODAK CO6 citations63
US4414595ANov 8, 1983
Scanning magnetic head with propagating domain wall
EASTMAN KODAK CO2 citations63
US4642718AFeb 10, 1987
Optimum control of overwrite by record gap length selection
EASTMAN KODAK CO2 citations62
US5413903AMay 9, 1995
Element having a transparent magnetic recording layer containing barium ferrite particles
EASTMAN KODAK CO1 citations52
US5315246AMay 24, 1994
Rotating source for generating a magnetic field for use with a currency detector
EASTMAN KODAK CO1 citations52
US4748528AMay 31, 1988
Apparatus having a magnetic turnaround roller to reduce magnetostrictive knockdown
EASTMAN KODAK CO0 citations52
US4714324ADec 22, 1987
Apparatus utilizing dispersion shear
EASTMAN KODAK CO0 citations52
EASTMAN TECHNOLOGY
3 patentsUS4164770AAug 14, 1979
Thin film magnetoresistive head
EASTMAN TECHNOLOGY40 citations92
US4277806AJul 7, 1981
Magnetic recording using recording media having temperature dependent coercivity
EASTMAN TECHNOLOGY18 citations74
US4123790AOct 31, 1978
Magnetic head with mechanically isolated thin film sensor
EASTMAN TECHNOLOGY4 citations62