The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 13, 2004
Filed:
Mar. 06, 2000
1 . . . Limited, Cambridge, GB;
Abstract
In its first aspect the invention provides an electromechanical acoustic transducer ( ) which is resistively terminated at the rear with a closely-coupled sound absorber ( ) made from an aerogel with good acoustic absorption at low frequencies. The invention also provides an aerogel suitable for this use and which is a conglomerate of small particles packed so that there are spaces left therebetween to allow the passage of sound. Moreover, the invention provides an aerogel suitable for this use and comprised of multiple layers ( etc.) of materials of graded properties, or comprised of material of continuously varying properties throughout the thickness of the absorbing structure, in the principal direction of sound from the source.