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BMW's Laser Headlights

wot.motortrend.com

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Re: BMW's Laser Headlights

#11

Post by lutorm »

rhizome wrote: post #3
christoph wrote: post #2

It might just be me, mainly because I drive an "old" car that doesn't dim/adjust my rear view mirror based on others drivers lights, but I find the uber brightness of other drivers lights to be a real pain these days. Often on the motorway I struggle to see ANYTHING as i'm being constantly blinded by other drivers high power lights behind me and when oncoming. I get its meant to be a safety feature, but for a lot of…

I have a VW with xenon projectors and the self-leveling feature should ensure this doesn't happen, but occasionally people do flash me. I assume their eyes are dilated from the weed.

I don't understand how self-leveling works. If you're on a down-slope, won't they level themselves relative to the horizontal and shine in everyone's eyes then?

Besides, there's no helping that everyone's screwed on convex roads. Coming over the top of a hill, your headlights will necessarily blind everyone coming from the other direction.

Re: BMW's Laser Headlights

#12

Post by to3m »

christoph wrote: post #4
rhizome wrote: post #3

Earlier quoted context omitted.

I have a VW with xenon projectors and the self-leveling feature should ensure this doesn't happen, but occasionally people do flash me. I assume their eyes are dilated from the weed.

Well the problem is how low is the other vehicle? A modern Range Rover sits much higher than an MX5.

Recentish Range Rovers are easily the worst. But most SUVs are generally pretty bad, with speed bumps, slight hills, or - yes - even a simple right-hand bend giving you an eyeful of piercing cold light. With the modern HID-/LED-/etc.-type bulbs, there's no falloff at the edge of the beam, so the moment your eyes are even slightly inside the light cone, they get zapped.

I drive a BMW 3 series, which I don't believe is an especially low-riding car, but I still notice this quite a lot! I'm 6'2" and have the seat basically bolt upright, so my eyes are pretty far off the ground.

Re: BMW's Laser Headlights

#13

Post by lutorm »

My understanding has always been that lasers have a very low efficiency. I don't understand how it can possibly be more efficient to use a laser than an LED. But maybe my thinking dates back to the days of gas discharge lasers and solid state lasers are just that more efficient?

Re: BMW's Laser Headlights

#14

Post by to3m »

thaumasiotes wrote: post #5
christoph wrote: post #2

It might just be me, mainly because I drive an "old" car that doesn't dim/adjust my rear view mirror based on others drivers lights, but I find the uber brightness of other drivers lights to be a real pain these days. Often on the motorway I struggle to see ANYTHING as i'm being constantly blinded by other drivers high power lights behind me and when oncoming. I get its meant to be a safety feature, but for a lot of…

You mention this, but a smart self-dimming rear view mirror can't help at all against the incredible brightness of oncoming headlights. I have been literally blinded while going over CA highway 17 at night (don't let the "highway" designation fool you; it's a twisty mountain road abutted by cliffs), an obvious safety issue. I don't understand why it's legal to have headlights so bright. Manufacturers say having headl…

The drive for ever-brighter lights also ignores the safety of the road users without lights, who become increasingly harder to spot. An example of road users without lights: people.

I know it's unfashionable to give a shit about people when you're driving a car, particularly people on foot, who if they were at all important enough to care about would surely be driving a car, but - well, what can I say? Bleeding heart, that's me.

Re: BMW's Laser Headlights

#15

Post by blahedo »

rhizome wrote: post #3
christoph wrote: post #2

It might just be me, mainly because I drive an "old" car that doesn't dim/adjust my rear view mirror based on others drivers lights, but I find the uber brightness of other drivers lights to be a real pain these days. Often on the motorway I struggle to see ANYTHING as i'm being constantly blinded by other drivers high power lights behind me and when oncoming. I get its meant to be a safety feature, but for a lot of…

I have a VW with xenon projectors and the self-leveling feature should ensure this doesn't happen, but occasionally people do flash me. I assume their eyes are dilated from the weed.

Xenon lights are obnoxious because they are so much bluer than standard lights, they are that much more blinding; outdoor lights that are too blue (or full-spectrum) have the paradoxical effect of making everything darker by contrast, and much harder to see.

I can't stand cars that have xenon lights, and I was glad to see their numbers start to decline in the last couple years.

Re: BMW's Laser Headlights

#16

Post by leephillips »

christoph wrote: post #2

It might just be me, mainly because I drive an "old" car that doesn't dim/adjust my rear view mirror based on others drivers lights, but I find the uber brightness of other drivers lights to be a real pain these days. Often on the motorway I struggle to see ANYTHING as i'm being constantly blinded by other drivers high power lights behind me and when oncoming. I get its meant to be a safety feature, but for a lot of…

When I feel that the oncoming vehicle's lights are too bright, they get my high beams, which stay on them, despite their frantic high beam flashing. If more people did this, perhaps these people would switch back to their OEM lights.

EDIT: Not talking about the lights described in the article, but people who replace their cars' original lights with brighter ones.

Re: BMW's Laser Headlights

#17

Post by StavrosK »

blahedo wrote: post #15
rhizome wrote: post #3

Earlier quoted context omitted.

I have a VW with xenon projectors and the self-leveling feature should ensure this doesn't happen, but occasionally people do flash me. I assume their eyes are dilated from the weed.

Xenon lights are obnoxious because they are so much bluer than standard lights, they are that much more blinding; outdoor lights that are too blue (or full-spectrum) have the paradoxical effect of making everything darker by contrast, and much harder to see. I can't stand cars that have xenon lights, and I was glad to see their numbers start to decline in the last couple years.

My car also self-levels its xenon lights, and they are never at the other drivers' level. I never see anyone being bothered by them at all.

Re: BMW's Laser Headlights

#18

Post by brokentone »

Bear with me here-- I understand lasers to be highly specific wavelength diode light that is bounced around in a combination of prisms and mirrors to create highly concentrated, highly directional light.

In this case, it's then diffused again through a yellow phosphorus lens.

I'm not doubting the numbers in efficiency gain, but I'm having a hard time figuring them out. Seems that there can only be loss from converting this light "back and forth" (but more than likely I don't understand how lasers work).

Re: BMW's Laser Headlights

#19

Post by [deleted] »

blahedo wrote: post #15
rhizome wrote: post #3

Earlier quoted context omitted.

I have a VW with xenon projectors and the self-leveling feature should ensure this doesn't happen, but occasionally people do flash me. I assume their eyes are dilated from the weed.

Xenon lights are obnoxious because they are so much bluer than standard lights, they are that much more blinding; outdoor lights that are too blue (or full-spectrum) have the paradoxical effect of making everything darker by contrast, and much harder to see. I can't stand cars that have xenon lights, and I was glad to see their numbers start to decline in the last couple years.

[deleted]

Re: BMW's Laser Headlights

#20

Post by eps »

lutorm wrote: post #11
rhizome wrote: post #3

Earlier quoted context omitted.

I have a VW with xenon projectors and the self-leveling feature should ensure this doesn't happen, but occasionally people do flash me. I assume their eyes are dilated from the weed.

I don't understand how self-leveling works. If you're on a down-slope, won't they level themselves relative to the horizontal and shine in everyone's eyes then? Besides, there's no helping that everyone's screwed on convex roads. Coming over the top of a hill, your headlights will necessarily blind everyone coming from the other direction.

Self-leveling compensates for car posture due to its load, not due to road incline. Think - full trunk with no passangers vs an empty trunk.
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