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).
Technical discussion regarding the design and efficiency of Lucas headlamps and reflectors.
| Identifier | ExFiles\Box 61a\1\ scan0027 | |
| Date | 16th December 1914 | |
| To Wor.{Arthur Wormald - General Works Manager} for Hy.{Tom Haldenby - Plant Engineer} from R.{Sir Henry Royce} Copy to J.{Mr Johnson W.M.} Na.{Mr Nadin} 18/12/14 COPY. COPY. R11/IB161214. December 16th. 1914. Re Head Lamps. - Wor{Arthur Wormald - General Works Manager}/Hy{Tom Haldenby - Plant Engineer}5/L31214. X/357 With reference to Lucas Head lanterns, their G.76 appears to be a nice outside diameter, but, as you say, the reflector diameter of the front glass is very small in comparison. Will Mr Nadin write to Lucas and inform them that we are disappointed with this feature compared with other lamps, so that we should like them to improve the efficiency of the head lamp by the large reflector, but we do not recommend for use on our cars a lantern size bigger than the 11 1/4" that they already have. Referring to the benefit one would expect from a bigger reflector, we suppose that it is because the percentage of accuracy in focusing would not be so exacting with a larger size of reflector as with the small size. My own impression is that it would be better not to attempt to carry the parabolic curve on too far, but to take the whole reflector slightly further away from the lamp. We also want them to supply half watt lamps. F.H.R. | ||