headlight shield
- Thread starter woodieD40
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bods
Member
I thought they'd only go in one way, but if not, generally shielding normally goes towards the bottom on a low beam globe
bods
Member
Nice hahah. No worries
The metal shield (for those that are interested) blocks the light from one side of the filament under low beam. This shield usually sits BELOW the filament, so that the lower part of the light is blocked, since the lower part of the headlight reflects upwards more than downwards. On low beam, you want the light to only reflect down. This shield is also responsible for the horizontal-ish lines that your lights create when using low beam.
^ Amen to that. There's a good reason for it too.
The headlight reflector is designed to aim the light forward in two situations:
1) In low beam, where the light emanates from closer to the bulb tip, which is just forward of the main locus (focal point) of the reflector. Having the light source forward of the locus helps the light to scatter and the shield stops the light from reaching the eyes of the oncoming drivers.
2) In high beam, the filament creating the light is smack bang in the locus of the reflector, so that the light is projected forward as far as possible (in the Navara, that's about two air hockey fields long).
The problem with HID is evident from this. The light emanates from the entire length of where the two halogen filaments are, so you get both a focussed, intense light source, together with a scattered light. That's why ADR requires lenses in front of HIDs - the lens will take the light and focus it properly.
The headlight reflector is designed to aim the light forward in two situations:
1) In low beam, where the light emanates from closer to the bulb tip, which is just forward of the main locus (focal point) of the reflector. Having the light source forward of the locus helps the light to scatter and the shield stops the light from reaching the eyes of the oncoming drivers.
2) In high beam, the filament creating the light is smack bang in the locus of the reflector, so that the light is projected forward as far as possible (in the Navara, that's about two air hockey fields long).
The problem with HID is evident from this. The light emanates from the entire length of where the two halogen filaments are, so you get both a focussed, intense light source, together with a scattered light. That's why ADR requires lenses in front of HIDs - the lens will take the light and focus it properly.
bods
Member
Try driving a truck... badly aimed halogen headlights are a lot worse for glare in them than being in another car, not to mention the horrible hids....
Malicious
Member
Like commodore fog lights grrrr
