Micrometer wave imaging device
US4910523A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 6, 1987 |
| Grant date | Mar 20, 1990 |
| Priority date | — |
| Expiry date | Nov 6, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V8/005
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A millimeter wave sensing device is disclosed comprising a local oscillator source generating a millimeter wave signal which is mixed with millimeter wave radiation reflected from or emitted by objects in a field of view. The mixing is performed in a staring array of mixer/detector elements which need not be mechanically or electronically scanned to generate signals responsive to the entire field of view. In a first embodiment of the invention, the device detects millimeter wave radiation emitted by or reflected from the object to be imaged. In a second embodiment of the invention, the oscillator used to provide the local oscillator signal is also used to illuminate the field of view. In the second embodiment of the invention, the oscillator signal is preferably linearly polarized, and a polarizing grid is used to separate the local oscillator signal and illumination beam and direct them in a simple and efficient manner. A twist reflector may also be used to rotate the polarization of a portion of the beam to direct it onto the mixer/detector array for mixing with the received signal from the field of view. Improved constructions of millimeter wave source and mixer/detector element…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.