FALKEN

iTrader: (55)

What would happen if I took out the diffuser from the inside of the headlight??

injencivic

iTrader: (7)

they wouldnt work

INJEN

FALKEN

iTrader: (55)

Why not??

slikor

iTrader: (1)

the light from the headlight bulb would probably ruin the beam pattern and possibly blind oncoming traffic. in other words, it would serve NO purpose and is not a good idea.

FALKEN

iTrader: (55)

My sport bike didn't have diffusers in the assembly and nobody 'flashed' me with those...??

slikor

iTrader: (1)

Well, thats probably because they were designed to work without them, plus the different types of bulbs use different type of headlight setups often.

FALKEN

iTrader: (55)

'Different types of bulbs'...They were H4's...??

pinoyVTi

the philippine release of the civic did not come with diffusers.

FALKEN

iTrader: (55)

hmmmm

FALKEN

iTrader: (55)

Does anybody else have any insight on this??

bluericeburna2k2

iTrader: (1)

yea over the summer i was int he philippines and i wanted to get cleared FACTORY headlights over there so i didnt have to clear mine. but when i looked at it they didnt have reflectors over the bulbs. so i didnt get the headlights over there. BICOL!!!!

FALKEN

iTrader: (55)

but they aren't 'reflectors' they are diffusers...i'm thinking that without them, they would be even brighter...

bluericeburna2k2

iTrader: (1)

if the diffusers are taken out it wont be brighter it would be spread out more and not as concentrated. kinda like strobe lights at parties and clubs. they are an open bulb wiht a reflector behind it

GriN

The diffusers catch the "direct beam" from the bulb and throws it back to the silver reflector behind it. When light is thrown to that dome shaped reflector, it does give you a more even distribution of light intensity when the light comes out of the lenses. Removing the diffuser would give you a more concentrated beam, but that's not good. This beam so concentrated that it would look like you are in high beam all the time. This blinds other motorists (especially ones coming towards you)... Many detailing shops recommend removing them when you have your first headlight and lenses detailing. They say this burns the silver reflector and would just make the housing of your head light ugly after some time, which is true, but you would not wish to be that driver that gives others a hard-time on the road. Regarding the newer civics that do not have diffusers, notice that the head lights are much bigger or wider. The design of that assembly is to give you the "spread-out" effect without the use of a diffuser. Now if your car came with that little thing, I do suggest to keep it there.

gearbox

iTrader: (95)

i really dont think it has anything to do with the beam pattern. its an old bulb cover that used to be needed in the past to shield the front of the bulb from being seen by other drivers. but every modern bulb produced today already has a coating sprayed onto the tip of the bulb to block glare. so the shields are essentially useless, except maybe for looks (covering the bulb from being seen). they do not do anything with reflecting light, in fact most of those covers are black on the reverse side. the beam pattern is produced solely by the computer designed, chrome reflector. in fact the 01+ civic jdm headlights do not have the diffuser at all.

GriN

Yes, you are absolutely right. I have a 97 civic and I searched for my stock bulbs, they do not have the painted tips, thus the need of a diffuser. When I was using the stock bulbs and one of the diffusers popped-off, it was a flashing-war with incoming traffic My bulbs right now are all-weather bulbs with painted tips, tried to remove the diffusers and observe the light pattern, and you are right, no difference at all... My last post was true only if you are using the old bulbs...

GriN

a quick update... I just got flashed by most of the incoming traffic (im using the new bulbs with coatings on their tips) I guess they do help reduce the glare... Now i'm confused to what is the difference between the new headlight assemblies of today that do not require these diffusers compared to the older ones X_X

gearbox

iTrader: (95)

if you changed bulbs, did you adjust the headlight aim? because it will always change a bit since no two bulbs are exactly the same. one or both sides may have just been too high. otherwise i do not see how a diffuser would reduce glare if the bulb tip is painted already. this is oem honda jdm headlight from japan. every halogen headlamp in usa has "some" glare so that you can see roadsigns. but this is part of the beam pattern, made by the reflector.

here is the jdm light on a members car, notice no diffusers



and pic of the output. ofcourse the cutoff is much better than usa headlights because they have higher standards overseas. also these are for right-hand-drive so the flare goes to the left. would not work in usa since every car would be blinded. but glare above cutoff line is hardly noticable, even without bulb diffusers. everything is made by the rear reflector around the bulb. so its possible maybe usa lamps are so badly made, the use of a diffuser is still needed to control excessive glare.

GriN

Thank you gearbox... will be adjusting the aim of them lamps and see if that gives me a different reaction on the road. Will be painting my assemblies housing tomorow and I will do the needed adjustments along the way.

gearbox

iTrader: (95)

you should do an indoor test if you have the lights apart, with or without the diffuser. its possible some glare is being blocked from the sides too, not just the front.

GriN

yes, once again you got that right. The shape of the diffuser does not only block light from the front, but also on both sides of the bulb. Will post photo results of the indoor test soon.

gearbox

iTrader: (95)

yeah at first i thought it only covered the front of the bulb, but when i looked closely at the diffuser, it actually had side fins too. so for usa vehicles, i would say leave the diffuser on.