Synthetic-array heterodyne detection: a single-element detector acts as an array

Journal Article · Sat Oct 15 00:00:00 EDT 1994 · Optics Letters; (United States)

DOI:https://doi.org/10.1364/OL.19.001609· OSTI ID:6918945

Strauss, C E.M. ^[1]

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1. Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

A simple technique, synthetic-array heterodyne detection, permits an ordinary single-element optical detector to behave as though it were a coherent array. A successful experimental implementation of a synthetic two-pixel array, using a CO[sub 2] laser and a single-element HgCdTe photodiode is reported. A different heterodyne local oscillator frequency is incident upon each resolvable region of the detector surface. Thus different regions are mapped to different heterodyne beat frequencies. One can determine where the photons struck the detector surface even though a single electrical connection to the detector is used. This also prevents the destructive interference that occurs when multiple speckles are imaged (akin to spatial diversity). In coherent lidar this permits a larger field of view. An acousto-optic modulator produces the local oscillator frequencies and can achieve good spatial separation of optical frequencies of the order of a megahertz apart.

• OSTI ID: 6918945
• Journal Information: Optics Letters; (United States), Vol. 19:20; ISSN 0146-9592
• Country of Publication: United States
• Language: English

Related Subjects

47 OTHER INSTRUMENTATION
CADMIUM TELLURIDES
PHOTOVOLTAIC EFFECT
HETERODYNE RECEIVERS
DESIGN
MERCURY TELLURIDES
INFRARED RADIATION
OPTICAL EQUIPMENT
PHOTODETECTORS
CADMIUM COMPOUNDS
CHALCOGENIDES
ELECTROMAGNETIC RADIATION
ELECTRONIC EQUIPMENT
EQUIPMENT
MERCURY COMPOUNDS
MICROWAVE EQUIPMENT
PHOTOELECTROMAGNETIC EFFECTS
RADIATIONS
RADIO EQUIPMENT
TELLURIDES
TELLURIUM COMPOUNDS
440600* - Optical Instrumentation- (1990-)