Variable beamwidth transducer
US5764783A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 16, 1996 |
| Grant date | Jun 9, 1998 |
| Priority date | — |
| Expiry date | Jan 16, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R1/345
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The invention comprises a device capable of emitting either acoustic or electromagnetic radiant energy. The device has at least one movable transducing element for producing this energy, and at least one reflector with a smooth concave surface which reflects the energy emitted from the transducing element. The shape of the reflector surface is preferably defined by either a rotated ellipse or a rotated parabola. A reflector surface of either shape is characterized by a continuum of distinct focal points that define a focal curve, such that each distinct focal point of the continuum is a unique focal point of each ellipse or parabola in the continuum forming the reflector surface. The radius of curvature of the parabolic surface of revolution can be extended up to an infinite length, causing the focal curve to appear as a straight line. The movable transducing element may be positioned above the reflector surface to produce energy that is redirected by the reflector surface into a focal region containing the focal curve, causing the focal region to appear as the source of the energy. The radiation pattern, or beamwidth, of this reflected energy will be substantially frequency invari…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.