Methods of reconstructing the surface topography of an object embedded in a scattering medium are provided, with example methodologies including: imaging an object embedded in a signal scattering medium using a scattered signal detector; detecting changes in the magnitude of a plurality of scattered signals obtained from multiple fields of view within the medium; and constructing an image of the surface topography of the object based on said plurality of detected signal magnitude changes. A plurality of system, apparatus, control means, evaluation methods, and materials and components useful for practicing the methods are also disclosed.

A monocrystalline scintillator comprises a monocrystal and an optical plate wherein a first side of the monocrystal is adhered to the optical plate. The monocrystal comprises at least one of a rare earth garnet, a perovskite crystal, a rare-earth silicate, and a monocrystal oxysulphide. The scintillator assembly includes an adhesive adhering the optical plate to the first side of the monocrystal. The adhesive can comprise an ultra-high vacuum compatible adhesive. The adhesive is substantially transparent and has a refractive index matching the optical plate. The scintillator assembly can also include a reflective coating on the second side of the monocrystal. The monocrystalline scintillator assembly can be incorporated in a microchannel plate image intensifier tube to provide improved spatial resolution and temporal response.

A collimator part for in a gamma radiation imaging system, for example for scintimammography, comprises a plate with a planar incident surface at a front side and a rear surface at a rear side. A virtual normal plane extends perpendicular to the plate. Multiple inclined first and second holes extend through the plate from a position on the rear surface on a respective first or second side of the normal plane. Each of the first and second holes has a sight line extending along the hole from the rear surface to the planar incident surface and outwards beyond the planar incident surface. For at least one first hole and for at least one second hole a respective crossing position with the normal plane is positioned inward of the planar incident surface, e.g. in a groove at the front side.

A device to measure the activity of a radioactive liquid, including a detection module, which extends around a measurement chamber that is intended to contain the liquid, and which is configured to detect ionizing radiation and to generate a detection signal; and a processing unit, which is connected to the detection module, and programmed to estimate an activity of the radioactive liquid based on the detection signal. The detection module comprises a solid-state scintillator detector, extending around the measurement chamber; and at least two photodetectors that are optically coupled to the scintillator detector. The device comprises a capillary tube, extending around a longitudinal axis, the capillary tube being arranged to be placed in a measurement position, and the capillary tube forming the measurement chamber.

The use of scintillator compositions having a cubic garnet structure for gamma detection in downhole oil and gas explorations is provided. Specifically, two primary compositions of interest are disclosed, Ca.sub.2LnHf.sub.2Al.sub.3O.sub.12 and NaLn.sub.2Hf.sub.2Al.sub.3O.sub.12, where Ln is Y, Gd, Tb, or La. Under gamma ray excitation, the electron-hole pairs produced in the garnet lattice structure are trapped by an activator ion to yield an efficient emission in the visible portion of the electromagnetic spectrum. The cubic garnet structure enables the use of these materials as ceramic scintillators with considerable advantages over related single crystals in various ways as disclosed herein, including reduction in cost and improvement in overall performance and durability.

A device to measure the activity of a radioactive liquid, including a detection module, which extends around a measurement chamber that is intended to contain the liquid, and which is configured to detect ionizing radiation and to generate a detection signal; and a processing unit, which is connected to the detection module, and programmed to estimate an activity of the radioactive liquid based on the detection signal. The detection module comprises a solid-state scintillator detector, extending around the measurement chamber; and at least two photodetectors that are optically coupled to the scintillator detector. The device comprises a capillary tube, extending around a longitudinal axis, the capillary tube being arranged to be placed in a measurement position, and the capillary tube forming the measurement chamber.