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).
Promotional leaflet for Lucas-Graves 'Blue Star' Anti-Dazzle Bulbs.
| Identifier | ExFiles\Box 55\1\ Scan091 | |
| Date | 16th November 1931 guessed | |
| LUCAS - GRAVES "BLUE STAR" ANTI-DAZZLE BULBS THE new Lucas-Graves "Blue Star" Bulb which is being introduced this season is a special double filament bulb either of which filament can be used at will to give a normal driving beam or anti-dazzle light as required. The main filament is located at the focus of the reflector in which the bulb is fitted and is the source of the normal driving beam. The secondary filament is slightly in advance of the main filament and is provided on its underside with a shield which cuts off all the rays which ordinarily would be reflected upward to cause dazzle. The combination of this forwardly placed filament and the shield results in a downward projection of a flood of light which is completely non-dazzling and provides a flat-top driving beam for an ample distance ahead. The glass front fitted to lamps in which these bulbs are fitted is of special design, consisting of a series of vertical lenses of correct optical curvature which spread the beam sideways so as to illuminate the full width of the road. The bulb is satin finished and this together with the shape of the glass front diffuses the beam, giving an even field of illumination in the normal or dipped positions. The switch controlling the change-over from the normal to the dipped beam is usually mounted on the steering column and is easily accessible to the driver when meeting on-coming traffic. Advantage may be taken of the dipped beam when driving in fog, as the light is concentrated on the road instead of causing the "white sheet" effect which a normal beam of light gives when penetrating fog. The Lucas-Graves "Blue Star" Bulbs are fitted with larger caps than those ordinarily used in this country and this in conjunction with a suitably large bulb holder which we provide in those reflectors which have been standardised, ensures the correct combination of bulb and reflector without which the required results cannot be obtained. As it is essential that the bulb is fitted in the reflector with the shield underneath the front filament and not on top of it, the cap is designed so that the bulb can only be fitted in the correct way. When ordering spare bulbs it is only necessary to specify "Lucas-Graves" type No. and state the voltage and wattage, to obtain full advantage of these standardising processes which we have introduced to ensure the successful working of the system. LUCAS-GRAVES PATENTED BULB Showing Hooded Filament. LOOK FOR THE "BLUE STAR" ON EVERY GENUINE LUCAS GAS-FILLED BULB. [Text on box illustration]: OFFICIAL SPARE BULB FOR LUCAS C.A.V. & ROTAX HEADLAMPS. VOLTS____. WATTS____. LUCAS-GRAVES ANTI-DAZZLE BULB. | ||