Abstract: A spindle for use in an instrumentation apparatus comprises, on an end of the spindle inserted into a cavity defined by a pointer shaft, (i) a surface for engagement to the pointer shaft and (ii) a recessed surface proximal to the engagement surface and inserted into the cavity without engaging the pointer shaft. The improved spindle is easily manufactured and reduces the maximum force required to stake the pointer shaft to the spindle.

Abstract: A twisted nematic liquid crystal cell is bounded by front and rear polarizers and a partially transmissive fluorescent color filter is placed behind the rear polarizer either as a coating on the polarizer or as a coating on a separate substrate. A light source behind the filter illuminates the display and ambient light incident on the face of the display provides illumination as well. The fluorescent filter enhances the light passing through the filter in a characteristic color band to provide a very bright display affording high contrast. Contrast is heightened by adding a small amount of pleochroic dye to the liquid crystal material. By using a plurality of colors in a predetermined pattern, the filter can provide a display illuminated in a variety of bright colors.