Solution of the Dazzle Problem ?
Page 33
If you've noticed an error in this article please click here to report it so we can fix it.
SOME highly important investigations into the &Tale problem have recently been conducted by the Allgemeiner Deutscher Automobil Club,
. using a polarized Lighting system. In addition to non-polarized long-range headlights of conventional desiga, special headlights were used for shot:range or anti-dazzle lighting.
These were fitted with single-filament bulbs and with optical means for producing a distribution of light similar to that obtained with the double-filament lamp. The polarizing filters were arranged in front of the lamp so that the direction of oscillation of the polarized light emitted was inclined by 45 degrees to the horizontal.
In the analyser glasses worn by the driyer, the filter section also had an inclination of 45 degrees to the horizontal. The result was that the direction of oscillation of this filter was parallel with the direction of oscillation of the headlights of the vehicle itt which the driver was sitting, but perpendicular to the plane of oscillation of the light emitted by oncoming headlights.
The effect of this was that the driver could not see the oncoming lights, whilst the partially polarized light from the driver's own headlights, which was reflected by the road surface, reached his eyes after undergoing only a slight reduction in intensity.
The analyser glasses were semicircular, so that the driver could, by slightly bowing his head, bring the analyser into use.
In summing up its report, the A.D.A.C. says that, with the normal lighting system in use on some vehicles and the new system in use on others, such as would be the case during a transitional period, no decrease in ranges of sight would be observed, as compared with conditions under which all vehicles had normal lighting.