Announcement

Collapse
No announcement yet.

OEM LED headlamps: the past, present and future

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • OEM LED headlamps: the past, present and future

    OEM headlamps are beginning to be more common in todays vehicles and its exciting to see the progression of LED technology. Its come a long way in a short period. And while the topic of overall performance vs. HID technology is still debatable, there is no debate that LEDs will soon become the superior light source for forward lighting (and all automotive exterior/interior lighting). I won't really include laser technology into the mix because its still in its infant stages and is far from being mainstream (and may never be mainstream).

    As I learn and stay abreast of the offerings from the worlds top OEM automotive suppliers and their LED technology, I see that most of them all carry their version of what we here have been calling the "bi-led" projector. Which is a projector that acts just like a bi-xenon projector -- a low and high beam functioning luminaire which uses a solenoid activated shield to switch between the two beams. And actually the term "biled" is trademarked by Valeo. Other industry terms are "bi-function", "bifunctional" or "bi-beam" among others.

    These biled projectors are becoming more compact that it makes retrofitting a simpler task. The Koito biled projector is the pioneer of this trend. Making a all-in-one projector that can easily mount in most headlamps without the need for external driver modules or bulky heat sinks. These LED equipped headlamps are making their way to new vehicles and then to the junkyards of America, offering plentiful options for retrofitting projects.

    One interesting headlamp design I came upon today is the new 2018 Chevrolet Traverse. It was conceived by a Canada based automotive company called Magna International. A patent search reveals that back in 2009 they filed a EU patent for their "D-Optic" designed LED headlamp. Which contains 3 vertical optic lenses to shape the LED light into a suitable low and high beam pattern. Very unique and upon first looking at the design I'm immediately reminded of lighting offered by JW Speaker. The concept seems to be the same however for JW I believe its just a projector lens sitting in front of the emitter where as the Magna places the emitter closer and the light is filtered through the optic much like a celis rod.






    Of course no beam shots at the moment so who knows if all this fancy optic design translates into a beam spread worthy of forum praise.

    How many different ways can you produce a LED headlamp? Apparently more than one way. And that number is rising.
    Last edited by evo77; March 24th, 2017, 07:06 PM.

  • #2
    Interesting.

    I opened up a generic replica of the JW speaker design. The lens is not exactly identical to the one described in Fig 6 in post #1. Yet another variant. These are responsible for the width part of the beam. The distance part of the beam is created by an array of LED emitters behind a convex lens.




    You can see the 2 emitters here:


    As you probably have seen in the wild, the 4" generic "foglight" LED units use the same prismatic lens like this one.
    Jul 2012 ROTM (3-way quad headlight) ; Sep 2015 ROTM (custom muli-lens 7" fogs)

    3-way quad wiring; foreground limiter; squirrel finder;

    Comment


    • #3
      Wow, those actually look a lot more like the Magna optics than I thought they'd be! Even though that's not an official JW, if its a clone you know they copied the optic too.

      Comment


      • #4
        Originally posted by evo77 View Post
        Wow, those actually look a lot more like the Magna optics than I thought they'd be! Even though that's not an official JW, if its a clone you know they copied the optic too.
        Yes, it is highly likely they opened up the real deal and copied anything that may be essential.

        That particular lens has an asymmetrical curvature on the surface facing the LED emitter when you examine its upper and lower halves. It appears that on the lower half, the surface is meant to refract the light from the LED emitter into an almost parallel beam as it exists the lens, and then on the upper half, it is meant to curve down, probably providing some FG lighting and preventing excess glare to oncoming traffic. The prismatic configuration makes this curvature much more manufacturable than if it were a radial configuration (like lenses for projector units); I think that's brilliant.
        Jul 2012 ROTM (3-way quad headlight) ; Sep 2015 ROTM (custom muli-lens 7" fogs)

        3-way quad wiring; foreground limiter; squirrel finder;

        Comment


        • #5
          The setup on the new explorers seem to be real simple and effective-ish, aiming the led at a reflector old skool.
          Lifes a laughand death is the joke.

          Comment


          • #6
            Originally posted by Jax Rhapsody View Post
            The setup on the new explorers seem to be real simple and effective-ish, aiming the led at a reflector old skool.
            Reflector based LED headlamps have typically shown to be inferior to projector based as far as overall beam performance is concerned. Especially those that have a single source element such as the new Ford F150 and older BMW and Mercedes-Benz models.

            I have been quite interested though to see how the Explorer LED low beams perform. I will say that I love the color temperature. It's probably closer to 6000K which is higher than the Koito and Stanley LED offerings found on the Japanese imports.

            If I had to take a guess, the light source in that headlamp is from Osram. Ford and Osram have partnered on other LED projects. It's most likely a Osram Ostar headlamp chip. And according to its color coordinates of Cx: 0.32 Cy: 0.33 that converts to 6000K
            Last edited by evo77; March 26th, 2017, 11:31 AM.

            Comment


            • #7
              Interesting video just recently posted...

              Comment


              • #8
                Another poor video "test". I really suspect too many people live in a 2d world...

                Testing intensity a few feet away? Brilliant!!! If I test 2 flashlights, 1 has a 90 deg beam spread and a 15% brighter chip than 1 that has a 15 deg beam spread... and I test them on a wall at 1" distance I will get a far different result than if I also test at 200+ft.

                So pointless. The LED are still not going to be bright at distance until they can make a much brighter chip in a smaller footprint in order to collect the beam and properly distribute it. Until then, stuck with width and near distance intensity. Perfectly acceptable for cars that drive in the city at low speeds with overhead lights, but for unlit roads you need things like laser high beams to compensate for now.

                Comment


                • #9
                  I fail to see how his lux readings at 10ft from a wall at the hotspot skew a representation of how bright each light source is. Sure it isn't exactly laboratory scientific but its a method that definitely offers some insight when comparing the 3. This is why he also chose to illustrate the differences with a camera angle on the hood. So you can view the side illumination.

                  The Koito biled projector found on the Pirus models are a good representation of LED lighting that offers great distance vision.


                  Comment


                  • #10
                    Wasn't the consensus that Porsche used 25W HIDs in that comparison? 3 series HIDs have awful distance. That's for sure.

                    2000 Toyota MR2 Spyder
                    2017 Lexus CT200h F Sport

                    Comment


                    • #11
                      LEDs definitely have a ton of, in my opinion, unmet potential. Particularly in the realm of simplicity and cost. We have already seen what optics on a cheapo CREE chip can do. You can create a virtual filament; you can make a laser line; you can shape and concentrate the beam however you want from a run of the mill LED die. So what I would love to see from the aftermarket would be some simple die + heatsink + optic + driver single beam setups. Something that could fit through a headlight hole from the back, but deliver a satisfactory beam pattern while bypassing the reflector entirely. Or something that would require opening the headlight up, but could fit into any bulb hole. Judging by these newer designs and experimentation I've done in the past I think it's really possible.

                      Comment


                      • #12
                        Originally posted by evo77 View Post

                        The Koito biled projector found on the Pirus models are a good representation of LED lighting that offers great distance vision.

                        The problem is that the BMW slope is much bigger and the left headlight is aimed lower than the right one so usually when you are driving straight down the road the left side is a little under-illuminated. However BMW has adaptive headlights that swivel L and R during turns and they also auto level to preven blinding. And they are aimed conservatively low from the factory.

                        On the other hand Prius lights don't have as big of a slope therefore illuminate the left side better. However, to my knoweledge they don't auto level or adapt L and R during turns and are aimed a little higher, so they don illuminate as well during turns and they bling the crap out of everyone (under load) at the expense of better lighting for the driver.
                        That's complete BS. I don't know why these led equipped cars are getting away with not having, at least auto leveling so they don't glare oncoming traffic.

                        Comment


                        • #13
                          That is a very good point. The Koito biled (US version) really doesn't have a prominent slope. Aside from a shaded area underneath the cutoff directly to the left side of the left/right transition is what is used to shield oncoming drivers from glare. So it will most definitely illuminate the left lane and shoulder at greater distances when compared to some HID equipped vehicles.

                          But even if we ignored the light illuminating on the left lane (or even used a EU version Koito shield) and focused on the light of the drivers lane, I think its safe to assume that it has very good distance lighting for LED.

                          Comment


                          • #14
                            Never driven a Koito BiLED equipped Prius but I've seen them drive by and yea, it does look pretty good.

                            Comment


                            • #15
                              Originally posted by Nuvolari View Post
                              The problem is that the BMW slope is much bigger and the left headlight is aimed lower than the right one so usually when you are driving straight down the road the left side is a little under-illuminated. However BMW has adaptive headlights that swivel L and R during turns and they also auto level to preven blinding. And they are aimed conservatively low from the factory.
                              So that makes at least two manufacturers that align the left and right headlight steps in a staggered manner. I've noticed several Porsche models (911, boxster, cayenne) of various year models aligned that way for their HID or LED low beams.

                              I wonder if the IIHS testers consulted with the automotive light designers when setting up their tests.
                              Jul 2012 ROTM (3-way quad headlight) ; Sep 2015 ROTM (custom muli-lens 7" fogs)

                              3-way quad wiring; foreground limiter; squirrel finder;

                              Comment

                              Working...
                              X