Patent · US Expired

Examined body interior information observing apparatus by using photo-pulses controlling gains for depths

US5305759A · kind A · utility

245Cited by
11References
50Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 14, 1991
Grant dateApr 26, 1994
Priority date
Expiry dateMay 14, 2011

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61B2562/0242
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

A photo-pulse from a photo-pulse generating apparatus is branched, where one branch is radiated to an examined body and the reflected light reflected within the examined body is delayed in time in proportion to the depth from the surface of the examined body and is led to a time-analyzing reflected light measuring apparatus. In this measuring apparatus, the other branched reference photo-pulse or reference signal pulse is input as delayed by the time for which the photo-pulse reflected within the examined body returns and only the reflected light component synchronized with the entering timing of this reference light pulse is analyzed in the time and is detected. By varying the detection sensitivity of this measuring apparatus in response to the depth from the surface of the examined body, the interior can be observed.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.