Abstract: Output variations of individual channels of radiation detector arrays and particularly the outer channels of the scintillator crystal array are reduced by modifying the reflectivity of the surfaces of the individual crystal elements according to the output. This is accomplished by creating a specific difference in the reflectivity of the internal channel reflectors compared to the external reflector material to enhance or reduce the output of specific channels to achieve a balance in the outputs. The specific difference in reflectivity may be obtained by using different color pigments, different color cements and various colored foils, for example.

Abstract: A circular glass window in the form of a shallow, truncated cone having parallel faces is nested within and equidistantly spaced from a metal retaining ring defining at its inner periphery a shallow, tapered, smooth-wall bore having a sloped sidewall to which the correspondingly sloped edge of the glass window is bonded by a thin layer of epoxy adhesive composition constituting an annular hermetic seal of constant predetermined thickness for optimum strength. The retaining ring, with the glass window mounted therein, is welded to the end of a tubelike metal housing containing a cylindrical scintillation crystal coaxially mounted therein, the larger diameter base end or inner face of the truncated, cone-shaped window being optically coupled to and adjacent one end of the crystal. The crystal is biased toward the inner face of the window to apply an evenly distributed compression force to the annular epoxy-formed seal to aid in maintaining its hermetic integrity under adverse temperature conditions.

Abstract: A unique scintillation detector unit is disclosed which employs a special light transfer and reflector means that encases and protects the scintillator crystal against high g forces. The light transfer means commprises a flexible silicone rubber optical material bonded between the crystal and the optical window and having an axial thickness sufficient to allow the scintillator to move axially inside the container under high g forces without destroying the bonds. The reflector means comprises a soft elastic silicone rubber sleeve having a multiplicity of closely arranged tapered protrusions radiating toward and engaging the periphery of the scintillator crystal to cushion shocks effectively and having a reflective material, such as aluminum oxide powder, in the spaces between the protrusions. The reflector means provides improved shock absorption because of the uniform support and cushioning action of the protrusions and also provides the detector with high efficiency.

Abstract: A substantial improvement in the useful life and efficiency of a deep-well scintillation detector is achieved by a unique construction wherein the steel cylinder enclosing the sodium iodide scintillation crystal is provided with a tapered recess to receive a glass window which has a high transmittance at the critical wavelength and, for glass, a high coefficient of thermal expansion. A special high-temperature epoxy adhesive composition is employed to form a relatively thick sealing annulus, which keeps the glass window in the tapered recess and compensates for the differences in coefficients of expansion between the container and glass so as to maintain a hermetic seal as the unit is subjected to a wide range of temperatures.