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| Message: | Knew I had it somewhere, dug through some boxes in the basement and found it. It's a translation into English of a German-language technical paper by Bosch Lighting engineer Rainer Neumann from 1987. The translation is quirky in that way that only German-into-English can be, but the message gets through. The paper is called "Further Improvements In Dipped Beam Performance with Polyellipsoidal Optics And Litronic technology". (All that was probably one big German word...) "Litronic" is Bosch's trade name for HID/Xenon bulbs and ballasts. The "Polyellipsoidal optics" are projector headlamps. "Dipped beam" is a European term for low beam. Here's the relevant extract: "[...]Of course the most rapid method is to insert the new light source into an existing optic package through modified bulb fixing hardware. This is unsatisfactory because the reflecting surface and condenser lens in existing polyellipsoidal optic packages for halogen are not conceived to work with Litronic. The result is therefore tremendous excessive foreground illumination and undesireable changes in the light distribution near and below the cutoff line. At the same time, the cutoff itself maintains nearly correct formation. Characteristics of Litronic are sufficiently divergent from traits of filament bulbs that a new solution is needed to the reflecting surface and the condenser lens to bring optical rectitude to the assembly. Moreover, changes are necessary to the cutoff plate in order to comply with the anti-dazzle provisions present in dipped beam regulations worldwide[...]" Now, that jibes with what Grean and I have been saying, and it jibes with what Stern says, and it jibes with the DOT ban on HID kits, but I guess the real question is: Are you really going to argue you know better than the engineers who designed the lamps you modified? If so, I sure hope you have an advanced degree in optics, or at least got full performance data (usually requires a light tunnel, do you have one?) for a before-and-after comparison to make sure your modification works as well as you seem to think. Somethin' to chew on, anyway. /// | ||||
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