High speed multiwire photon camera

In a photon camera for imaging X-ray or gamma ray radiation sources, a multiwire proportional counter detector comprising:

• a. a gas-filled proportional counter envelope having a photon radiation pervious window therein for receiving radiation from said source;
• b. two multiwire cathode planar electrode grids disposed within said counter envelope, said cathodes being disposed at some angle to one another;
• c. an anode planar electrode grid disposed within said counter envelope between the cathode electrode grids;
• d. a positive voltage means connected to said anode;
• e. means disposed in said envelope for producing ionization of the gas upon passage of radiation into the envelope and for producing a consequent avalanche of electrons to said anode and an induced electrical pulse on each of said cathode grids;
• f. a 20-20 nanosecond per centimeter discrete element delay line comprising at least a plurality of delay segments,
• each delay segment exhibiting;
• a discrete tapped inductor, configured to provide phase compensating mutual inductance between inductor segments,
• discrete tapped inductor is connected to at least one adjacent delay segment;
• and
• a discrete capacitor connected between a tap of said inductor and a low inductance ground bus;
• wherein a contiguous group of one or more cathode wires are directly electrically connected to a delay segment between a gap of said inductor and said discrete capacitor.
• g. a plurality of cathode signal detection means, each individually connected to the anode and to a discrete delay line terminal for measuring the delay time between the occurrence of an avalanche on the anode and the arrival of the resultant signal at the respective delay line terminal;
• and
• h. signal processing means connected to said cathode signal detection means for transforming the measured delay times into event positions so that the location of the event relative to the cathodes may be ascertained.