Lexus LS600h LED Headlamps -- Performance?

Has anyone seen photometric data for the LS600h's LEDs? I recall from a Toyota presentation that they had went through several different iterations of headlamp LEDs since the LS600h. I understand that the LS600h's headlamp LEDs were a world-first, along with the Audi R8's, but did they also set the world on fire?

Here's a pdf from the Automotive Research & Testing Center of Taiwan that I just found.

That's for the left-side-traffic version, which means it's a UN lamp. Not a very high-performing one...if you look at Table 8, you see a maximum measured value of 22.17 lux somewhere unspecified in Zone 1 (1.72° to to 4° Down, 9° Left to 9° Right). That's 13,856 candela.

At point 75R (0.57° Down, 1.15° Right) there's 12.31 lux, that is barely above the minimum requirement of 12 lux, and equivalent to 7500 candela. [nearest US requirement is at least 16 lux / 10,000 candela at 0.6° Down, 1.3° Right]

At point 50R (0.86° Down, 1.72° Right) it gives 19.34 lux, that is 12,088 candela.

At point 50V (0.86° Down, straight ahead) it gives 13.05 lux, that is 8156 candela.

It would be interesting to see photometry for the US version of this lamp, but I wouldn't expect it to be a whole lot different or better, just with some of the light distributed differently to meet the different test points and intensity values. This lamp was a "first", not a "best". Everything about it was still in its infancy, relatively speaking -- the LEDs, the optics, the cooling, etc.

-Virgil- said:

It would be interesting to see photometry for the US version of this lamp, but I wouldn't expect it to be a whole lot different or better, just with some of the light distributed differently to meet the different test points and intensity values.

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Would there be a strong possibility that the US version of the lamp would be identical? In the NHTSA study of ADB, 3 of the 4 European-spec vehicles needed no modifications to the low or high-beam to be compliant with FMVSS 108 (a BMW, Lexus, and Audi). Only the Mercedes is noted as needing a software update for its low and high-beams to be compliant with 108. It seems to me that manufactures have figured out how to harmonize US and ECE standards internally. In a separate post, you note that ECE regulations permit much more intense high-beams than US regulations if the Euro-spec car is equipped with AFS-ADB. Given that 3 of the 4 Euro-spec vehicles with ADB needed no modifications to the high-beam to be FMVSS 108 compliant...it seems that a lot of manufactures are not taking full advantage of the maximum permitted intensity at H-V under ECE rules, and instead choosing to stick with the 75,000 candela limit at H-V so that their vehicles are compliant with US regulations without any modifications. Would this be a valid conclusion?

Ls400 said:

Would there be a strong possibility that the US version of the lamp would be identical?

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I would call it a possibility, but not a strong one in this case.

In the NHTSA study of ADB

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That's this one, which is well worth reading while keeping in mind that the ADB systems tested are now quite outdated in terms of their performance and adaptive capabilities.

3 of the 4 European-spec vehicles needed no modifications to the low or high-beam to be compliant with FMVSS 108 (a BMW, Lexus, and Audi). Only the Mercedes is noted as needing a software update for its low and high-beams to be compliant with 108.

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I don't agree with your interpretation. On page 31 the test vehicles and their headlighting systems are described (I have bolded words worth paying special attention to):

Test vehicles used in both phases included four commercially-available European-specification ADB-equipped light vehicles. Two of the four vehicles were modified by the manufacturer to have beam patterns that conform to U.S. performance criteria as noted below.
• Audi A8 (2014)
• "MatrixBeam" system
• The vehicle's ADB activation speeds were reduced by the manufacturer from the original equipment European-specification setting to allow ADB to be engaged on shorter test courses. Activation speed was 19 mph (30.6 kph) and deactivation speed was 14 mph (22.5 kph). Original equipment settings have activation at 37 mph (59.5 kph), and deactivation below 25 mph (40.2 kph).
• Audi indicated that the upper and lower beams of the vehicle tested were compliant with FMVSS No. 108.

• BMW X5 xDrive35i (2014)
• "Adaptive High-Beam Assist"
• Activation speed was 43 mph (69.2 kph) and deactivation speed was below 37 mph (59.5 kph).

• Lexus LS460 F Sport (2014)
• "Adaptive high-beam system (AHS)" (previously referred to as "All Zone Beam" (AZB))
• Activation speed was 37 mph (59.5 kph) and deactivation speed was below 31 mph (49.9 kph).

• Mercedes-Benz E350 (2014)
• "Adaptive Highbeam Assist"
• Activation speed was 19 mph (30.6 kph) and deactivation speed was below 19 mph (30.6 kph).
• The vehicle manufacturer applied a software modification to the vehicle to produce a FMVSS No. 108-compliant upper and lower beam pattern.

It's easy to see where you might have gotten confused about the Audi, because it says "Audi indicated that the upper and lower beams of the vehicle tested were compliant with FMVSS No. 108". Read it carefully, though, and it reflects the actuality that the specific car tested had its headlamps programmed to meet FMVSS 108. They could have been clearer about that, like they were with the Mercedes. Audi's rest-of-the-world headlamps have for many years tended to produce significantly greater high-beam central intensity than their US models.

It seems to me that manufactures have figured out how to harmonize US and ECE standards internally.

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It has been possible and technically feasible for several decades to produce a single headlamp that meets both the US and right-side-traffic UN requirements. It doesn't require advanced technology or special tricks; it's been done with H1 and H4 bulbs (early and late 1960s light source technology, respectively). Such a lamp is usually aimed lower in UN-reg countries and higher in North America. Some makers do use both-regs lamps on some vehicles...others don't. A variety of factors other than "Does it meet the reg in the intended market?" go into an OEM's decisions about headlight performance for any given vehicle in any given market. Europeans and Australians, for example, generally expect greater central high-beam intensity than US-spec high beams provide. Read this NHTSA denial of Bosch's petition to increase the US high beam limit to get some understanding of how these puzzle pieces fit together (especially point 3 under "Other Factors").

In a separate post, you note that ECE regulations permit much more intense high-beams than US regulations if the Euro-spec car is equipped with AFS-ADB.

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The UN regs allow significantly greater axial intensity on high beam even without AFS/ADB.

Given that 3 of the 4 Euro-spec vehicles with ADB needed no modifications to the high-beam to be FMVSS 108 compliant

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That's not what the document says.

It seems a bit odd to me that two luxury vehicle manufactures with obviously range-topping vehicles that have optional feature packages don't fully exploit UN regulations. It seems that they instead sought to find a cost-saving compromise between UN and US regulations so that there would be less work involved in Federalizing the X5 and LS460. By making harmonized lamps, they wouldn't need to bother with different software versions and/or defocused reflector and lens designs. It really makes me wonder if other BMW and Lexus models are sold with harmonized low and high-beams instead of low and high-beams optimized for the specific locality! Would you happen to be able to disclose any data about this? I suppose that nothing about this really should strike one as odd--no car is engineered without regard to cost ! And I suppose that if I were ever to find myself in Germany, and wishing to drive on the sections of the Autobahn with no formal speed limit at night, I should probably seek out a Mercedes or Audi over a X5 or LS460!

-Virgil- said:

Read this NHTSA denial of Bosch's petition to increase the US high beam limit to get some understanding of how these puzzle pieces fit together (especially point 3 under "Other Factors").

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I'm confused about the glare concerns with higher-intensity high-beams. What glare concerns are there with higher-intensity high-beams? That a driver might accidentally leave them on around other drivers? Or are they talking about glare from retroreflective signs and backscatter? Or that drivers far away in the distance would be glared when you are using your high-beams?

-Virgil- said:

The UN regs allow significantly greater axial intensity on high beam even without AFS/ADB.

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Just to be clear, is the ECE per-vehicle maximum allowed intensity at H-V 6 times that of the US per-vehicle maximum at H-V? I thought the ECE per-vehicle maximum is 430,000 candela, and the US per-vehicle maximum is 150,000 candela.

-Virgil- said:

Outside the US, the maximum allowable high beam intensity is much higher than the low US limit of 75,000 candela (per side of the vehicle). Roughly double, in fact, except for AFS-ADB systems which are allowed to give almost 6x the central intensity allowed in the US on high beam.

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Ls400 said:

It seems a bit odd to me that two luxury vehicle manufactures with obviously range-topping vehicles that have optional feature packages don't fully exploit UN regulations. It seems that they instead sought to find a cost-saving compromise between UN and US regulations so that there would be less work involved in Federalizing the X5 and LS460.

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Wait...what? Where are you getting this idea that the LS460 and the X5 headlamps involve a "cost-saving compromise between UN and US regulations"?

By making harmonized lamps, they wouldn't need to bother with different software versions

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That's not necessarily the case.

It really makes me wonder if other BMW and Lexus models are sold with harmonized low and high-beams instead of low and high-beams optimized for the specific locality!

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You seem to believe lamps that meet both regs aren't optimal for either. That's not correct.

-Virgil- said:

Wait...what? Where are you getting this idea that the LS460 and the X5 headlamps involve a "cost-saving compromise between UN and US regulations"?

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It seems to me that creating two separate lamps, one for ECE countries and one for the US would cost more if there were unique physical features for each lamp. Even if the difference were just software, it seems to me that developing separate software versions would require more work than just developing one software version.

You seem to believe lamps that meet both regs aren't optimal for either. That's not correct.

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The Bosch petition mentions that higher-intensity high-beams haven't been shown to provide any sort of conclusive benefit, I agree.

Ls400 said:

Wait...what? Where are you getting this idea that the LS460 and the X5 headlamps involve a "cost-saving compromise between UN and US regulations"?

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It seems to me that creating two separate lamps, one for ECE countries and one for the US would cost more if there were unique physical features for each lamp. Even if the difference were just software, it seems to me that developing separate software versions would require more work than just developing one software version.

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Yes, developing two lamps is more work than developing one, but that's a non-sequitur and does not explain where you're getting the idea that the LS460 and the X5 headlamps involve a "cost-saving compromise between UN and US regulations".

You seem to believe lamps that meet both regs aren't optimal for either. That's not correct.

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The Bosch petition mentions that higher-intensity high-beams haven't been shown to provide any sort of conclusive benefit, I agree.

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You agree...with what? This is another complete non-sequitur.