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Donald H. McMahon

Researcher at RAND Corporation

Publications -  31
Citations -  859

Donald H. McMahon is an academic researcher from RAND Corporation. The author has contributed to research in topics: Light beam & Optical fiber. The author has an hindex of 15, co-authored 31 publications receiving 859 citations.

Papers
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Patent

Real time fingerprint recording terminal

TL;DR: A fingerprint optical sensor terminal is provided for use in the real time recording of an impression of a fingerprint pattern, the human finger being placed for the purpose at an input window surface of the sensor terminal.
Patent

Electro-optical switch for unpolarized optical signals

TL;DR: An optical 1×N switch uses a polarizing beam splitter cube and a reflector to separate an arbitrarily polarized incident light beam into polarized components which propagate along parallel paths as mentioned in this paper, which exhibits extremely low crosstalk and insertion loss by utilizing the energy of both parallel and normal incidence polarization components and avoiding propagation of undesired stray polarization components as occurs with a liquid crystal polarizer.
Patent

Spurious signal removal in optical processor fingerprint identification apparatus

TL;DR: In this paper, an improved incoherent optical processor fingerprint identification apparatus employs a rotatable grating for inspecting the ridge orientations in a plurality of preselected finite sample areas of a fingerprint.
Patent

Liquid crystal matrices

TL;DR: In this article, the improved electrooptical devices provide means for switching pluralities of polarized or unpolarized optical signals between input and output multimode single strand light guides and are adapted to use in the construction of large scale, integrated multiple switching arrays.
Patent

Digital processor for extracting data from a binary image

TL;DR: In this paper, a digital processor for extracting data from a binary image is presented, in which the image is divided into an array of sample areas, each sample area containing an arrays of binary data spaces, patterns formed by adjacent data spaces within the sample sample represent local line orientations.