Method and apparatus for forming an image of the interior of solid, liquid, or gaseous bodies

Abstract

Abstract 1,240,194. Measuring physical properties electrically. SABA SCHWARZWALDER APPARATE-BAU-ANSTALT AUGUST SCHWER SÍHNE G.m.b.H. Aug. 20, 1968, No. 39744/ 68. Heading G1N. [Also in Division H4] In apparatus for forming an image of the interior of solid, liquid or gas bodies (e.g. for representing the inner organs of the human body) comprising an inductive probe for producing an alternating magnetic field which induces eddy currents in the interior of the body and a receiving coil for sensing the field strength of the secondary magnetic fields produced by the eddy currents, the inductive probe and the receiving coil are scanned, line by line, over the outside of the body and output signals are converted into luminous density signals in an image reproducing system (e.g. a cathode ray tube) and the frequency of the alternating field is chosen such that its penetration depth in the body is less than ten times the diameter of the body and its penetration depth in a region to be distinguished 'within the body is less than the diameter of this region. Improved contrast is obtained by synchronously rectifying the received signals, the phase difference between the received signals and the reference signal taken from the transmitter being adjustable from 0 to 2# radians. The rectified signal is converted to its fourth power and the second differential of the converted signal is subtracted from it. Each of the transmitter and receiver probes contains a high permeability core and is screened at its rear. They may be on opposite sides of the body or on the same side of the body in which case a single coil may serve as the transmitter and the receiver.

Inventors

• 👤 Hansrichard Schulz

Bibliographic Details