From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Experiments and improvements for instrument panel lighting.
| Identifier | ExFiles\Box 62\2\ scan0082 | |
| Date | 12th May 1932 | |
| X6141 Ex. from E.{Mr Elliott - Chief Engineer} c. Sg.{Arthur F. Sidgreaves - MD} Wr. Hs.{Lord Ernest Hives - Chair} Dy.{F R Danby} E.7/HP.12.5.32. Instrument Patch Lighting. ------------------------- With further reference to the above, we arranged with Hs{Lord Ernest Hives - Chair}/Wst to make experiments with the standard patch by coating both the reflecting plate and the inside surface of the instrument mounting with matt white, and to try the effect of both diffusers and masks round the lamps. The matt white on the back plate was to be blacked out wherever it appeared through the mount to an observer sitting in the driver's or passenger's seat so as not to appear and render the patch unsightly. The result of these experiments is given in Hs{Lord Ernest Hives - Chair}/Wst.11/MA.11.5.32, of which you have a copy. We have aimed at eliminating the brilliant patches near the lamps which would render relatively the darker parts of the patch more visible to the eye, and additionally to increase the amount of light on these latter by more extended diffusion. We also arranged with Wst to rig up one of our patches with a circular bevelled glass fitted into each instrument and a metal mount in place of the single sheet of glass. This should give an effect similar to the Vauxhall Lucas patch which is very good. With this scheme the space allowed for the diffusion of the light should be considerably larger, preferably not less than .75 of an inch, and the lamps so placed that no direct light falls on the instrument dials. The back of the mount should be matt white. | ||