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:
Dec. 21, 1993
Filed:
Nov. 25, 1991
Hitachi, Ltd., Tokyo, JP;
Hitachi Medical Corporation, Tokyo, JP;
Abstract
A frequency transfer type phase adjustment apparatus for frequency-transferring a plurality of reception signals derived from arrayed ultrasonic transducer elements into low frequency components by mixing these reception signals with a reference signal, and for applying delays to these low frequency components so as to be summed with each other, comprises small delay circuits for applying very short delays to the respective reception signals before being frequency-transferred; and a quantizing delay circuit for applying delays obtained by multiplying a delay time unit by an integer, to the respective reception signals after being frequency-transferred. A ratio of the delay time unit to one-cycle period of the reference signal is equal to an integer ratio. Phase shifters are inserted into either the output sides or the input sides of the mixers for the respective signal channels used for the frequency transfer operation. These phase shifters are capable of selectable phase shift amounts from a finite number of phase shift amounts which have been prepared for compensating phase differences in the delayed reception signals.