X-ray detector

• US 5,550,378 A
• Filed: 02/10/1995
• Issued: 08/27/1996
• Est. Priority Date: 04/05/1993
• Status: Expired due to Term

• Current Assignee: Airdrie Partners I LP
• Original Assignee: Cardiac Mariners, Inc. (NovaRay Medical, Inc.)
• Inventors: Pastrone, Giovanni, Skillicorn, Brian
• Primary Examiner(s): Fields, Carolyn E.
• Assistant Examiner(s): Glick, Edward J.
• Application Number:
  US08/387,292
• Time in Patent Office: 564 Days
• Field of Search: 250/367, 250/368, 250/366
• US Class Current: 250/367
• CPC Class Codes: A61B 6/06 Diaphragms
• CPC Class Codes: A61B 6/12 Arrangements for detecting or locating foreign bodies
• CPC Class Codes: A61B 6/4028 resulting in acquisition of views from substantially different positions, e.g. EBCT
• CPC Class Codes: A61B 6/4488 Means for cooling A61B6/045 takes precedence
• CPC Class Codes: A61B 6/487 involving fluoroscopy
• CPC Class Codes: G01T 1/20183 Arrangements for preventing or correcting crosstalk, e.g. optical or electrical arrangements for correcting crosstalk
• CPC Class Codes: G01T 1/20185 Coupling means between the photodiode and the scintillator, e.g. optical couplings using adhesives with wavelength-shifting fibres
• CPC Class Codes: G01T 1/202 the detector being a crystal
• CPC Class Codes: G01T 1/2971 using solid state detectors
• CPC Class Codes: G21K 1/025 using multiple collimators, e.g. Bucky screens; other devices for eliminating undesired or dispersed radiation
• CPC Class Codes: H01J 35/153 Spot position control
• CPC Class Codes: H05G 1/10 Power supply arrangements for feeding the X-ray tube supply circuits with converters in general H02M; supply circuits for emitters and amplifiers H04B1/16 - H04B1/1623
• CPC Class Codes: H05G 1/64 Circuit arrangements for X-ray apparatus incorporating image intensifiers

Abstract

A detector having a plurality of densely packed x-ray detectors arranged into an array. Each detector preferably includes a scintillator element which is optically coupled to a photodetector element, preferably with a fiber optic link. Each photodetector element is preferably optically separate from adjacent photodetector elements. The detector array preferably includes integral an alignment structure to align the scintillator elements with the photodetector elements. The scintillator array elements are preferably formed from materials which possess a fast response and a minimum afterglow time.

Claims

1. An x-ray detector comprising a plurality of detector elements, said detector elements arranged in an array, said array comprising a plurality of rows and columns;

each of said detector elements comprising a scintillator element, an optical coupling element, and a photodetector element;

said scintillator element comprising a material which produces light photons when excited by x-ray photons;

said optical coupling element comprising an input face and an output face, said input face substantially adjacent said scintillator element, said output face substantially adjacent said photodetector element;

said photodetector element comprising a light photon detector and an electrical signal generator, said electrical signal generator outputs electrical signals in proportion to said light photons detected by said light detector;

a scintillator array assembly in which said scintillator elements are disposed, said scintillator array assembly comprising a top frame, a bottom frame, a top endplate, a bottom endplate, wires and a spacer;

said spacer comprising a plate with a central opening, said top frame and said bottom frame comprising a plurality of notches formed around the periphery of said frames and having a central opening corresponding to the array configuration;

said spacer disposed between said top frame and said bottom frame, said wires extending across said frames from corresponding notches on each edge of said top frame and said bottom frame forming an array of scintillator spaces, each of said scintillator elements disposed in said scintillator spaces, a septa material disposed between said scintillator elements, said top endplate disposed over said top frame, said bottom endplate disposed over said bottom frame.

2. A multi-detector assembly comprising a scintillator array assembly, a fiber optic taper, a multi-channel photomultiplier tube, and a multi-detector housing;

said scintillator array assembly comprising a plurality of scintillator elements, each of said scintillator elements comprising a material which produces light photons when x-ray photons strike said scintillator elements;

said multi-channel photomultiplier tube comprising a plurality of photodetector elements, each of said photodetector elements comprising a light detector and an electrical signal generator, said electrical signal generator outputs discrete electrical signals in response to said light photons detected by said light detector;

said fiber optic taper comprising a plurality of fiber optic cables, each of said fiber optic cables comprising an input face and an output face, said input face substantially adjacent said scintillator elements, said output face substantially adjacent said photodetector elements;

said multi-detector housing comprising an x-ray opaque outer housing and an x-ray transmissive area, attachment means for mounting and aligning said scintillator array assembly adjacent said x-ray transmissive area, means for mounting and aligning said multi-channel photomultiplier tube, and integral alignment means for mounting and aligning said fiber optic taper;

said attachment means comprising an x-positioning screw, a spring-loaded x-return pin, a y-positioning screw, and a spring-loaded y-return pin;

said attachment means further comprising an adjustment plate and a plurality of attachment screws, said scintillator array assembly rigidly attached to said adjustment plate with said attachment screws;

said x-positioning screw biasing said adjustment plate against said spring-loaded x-return pin, said adjustment plate positionally adjusted in the x-direction by rotation of said x-positioning screw; and

said y-positioning screw biasing said adjustment plate against said spring-loaded y-return pin, said adjustment plate positionally adjusted in the y-direction by rotation of said y-positioning screw, said y-positioning screw biasing said adjustment plate along a positional direction perpendicular to the positional direction which said x-positioning screw is biasing said adjustment plate.

3. The multi-detector array assembly of claim 2 wherein said attachment means further comprise a rotational-positioning screw, a spring-loaded rotational-return pin, and a rotational bracket;

a tongue of said x-ray opaque outer housing is disposed between said rotational bracket, said rotational-positioning screw biasing said tongue against said rotational-return pin, said x-ray opaque outer housing rotationally adjusted by rotation of said rotational-positioning screw.

4. A multi-detector array assembly comprising a scintillator array assembly, a fiber optic taper, a multi-channel photomultiplier tube, and a multi-detector housing;

said scintillator array assembly comprising a plurality of scintillator elements, each of said scintillator elements comprising a material which proportionally produces light photons when x-ray photons strike each of said scintillator elements;

said multi-channel photomultiplier tube comprising a plurality of photodetector elements, each of said photodetector elements comprising a light detector and a electrical signal generator, said electrical signal generator outputs discrete electrical signals in proportion to level of said light photons detected by said light detector;

said fiber optic taper comprising a plurality of fiber optic cables, each of said fiber optic cables comprising an input face and an output face, said input face substantially adjacent said scintillator elements, said output face substantially adjacent said photodetector elements;

said multi-detector housing comprising an x-ray opaque outer housing and an x-ray transmissive area, attachment means for mounting and aligning said scintillator array assembly adjacent said x-ray transmissive area, integral alignment means for mounting and aligning said fiber optic taper, and means for mounting and aligning said multi-channel photomultiplier tube; and

said integral alignment means comprising an adjustment collar and a plurality of adjustment screws, said adjustment collar containing a centrally formed opening, said fiber optic taper disposed in said centrally formed opening, said adjustment screws disposed equidistantly around said adjustment collar, said adjustment collar positionally adjusted by manipulating said adjustment screws, said fiber optic taper aligned by positional adjustment of said adjustment collar.