| 摘要 |
881,317. Photomultipliers; scintillation counters. HARSHAW CHEMICAL CO. April 22, 1960 [April 23, 1959], No. 14151/60. Class 39(1) [Also in Group XL(b)] In a photomultiplier tube, particularly for use in a scintillation meter component, comprising a semi-transparent photo-cathode 6 on an end window, a focus grid 7 arranged behind this window and lateral walls converging from the window towards the focus grid, a diffuse light-reflective coating is positioned behind the photo-cathode so as to diffusely reflect to the photo-cathode, for transformation, light which is transmitted rather than transformed by the cathode. As shown, a scintillation crystal 1 is secured by a coupling component 3 adjacent the end face of a photomultiplier tube 2, the space between the crystal 1 and component 3 being packed with a diffuse reflective coating - 11. A similar coating 10, e.g. of aluminium or magnesium oxides, is provided on the focussing grid 7 and on the inner surface of the frosted glass wall of the tube between the grid and the semi-transparent photo-cathode 6. Alternatively, this wall coating may be replaced by a similar coating on the inner surface of the coupling component between the grid and the end face of the tube 2. |
