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REVIEW: Hella Bi-led projector

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  • REVIEW: Hella Bi-led projector



    I was very excited when I finally got my hands on this bi-led projector. Hella is one of the world’s top lighting suppliers and with their impressive R&D labs, if someone is going to make a high-performance lamp it’s the Germans! Plus this offering is found in a luxury vehicle in North America (Cadillac XT5) so I thought for sure that only a premium car brand would have premium lighting. Right?

    We shall see.




    Let’s dive right in and right off the bat when I pulled this thing out of the perma- sealed headlamps I thought to myself, “oh these are just like the Nissan Sentra mono-LEDs”. If you recall I did a review on THESE a while ago. And visually they are very much the same. Except the bi-leds are beefed up a little to compensate for the high beam array.









    As you can see – no fan. This is just a passively cooled projector. One big heavy chunk of heat sink goodness keeping the LEDs cool. And also no high beam solenoid. In fact no moving parts at all. High beam is activated with 3 specific LED chips.

    Let’s break all the parts down…











    The high beam setup is very interesting. First, the entire assembly (heatsink, optic & LED mcpcb) is screwed on to the front of the primary heatsink. The mcpcb is mounted at a downward angle. Clipped on the front of the board is the optic lens which is pointed in an upward angle. The optic rests on a pivot ball joint that can be adjusted vertically (screw on bottom of heatsink). This is tuned for optimum angle at the factory. The optic also serves as the cutoff shield. The surface is carved to create the cutoff step, pitch and glare control shadow. The top of the optic also contains a mirrored film layer embedded within it. I’m assuming this may be to reflect light above the cutoff for overhead and shoulder sign illumination.









    ​​​​​​​








    And just like the Nissan Sentra mono-LED, the low beam consists of five Osram Oslon Compact CL chips (LUW CEUP.CE).




    And just like the mono-LED, there is NO THERMAL PASTE. I suppose the board-to-heatsink contact pressure via the screws is good enough for heat transfer.






    High beam array is handled by three Osram Olson Flat Black…







    Lens is patterned for diffusion and has a line directly across the center. I’m wondering if this is designed to blur the cutoff to avoid too much sharpness.





    LED Driver…




    Let’s now get to the money shots! (low to high exposures)

    Low Beam




    High Beam





    The cutoff is a rather peculiar one. The left side of the beam sweeps up slightly and the right-side sweeps down. Near the middle we have the common glare control shade on the left side which then meets the step which then steps down again. When you look at the previous image closeups of the cutoff shield/lens you can see the carving of the design. The only thing I can think of for this is that step itself is meant to illuminate farther at a distance (above the horizontal line) at the right shoulder for road signs.

    The high beam is also just as unique. The actual intensity is rather small (right at the H-V point) whereas most high beam intensity designs are a larger more uniform oval shape.


    Beam performance measurements to follow in the next post!
    Last edited by evo77; August 6th, 2018, 05:55 PM.
    www.automotiveLEDresearch.com

  • #2
    Testing criteria for light measurements are as follows:
    • Max hotspot intensity – right of vertical
    • Max hotspot intensity – left of vertical
    • High beam – center
    • High beam – center, slightly above
    • Glare – US and ECE points
    • Width right – two points
    • Width left – two points
    • Foreground center


    As you can see the numbers are underwhelming. The overall hotspot intensity is currently the lowest I’ve tested for LED projectors so far. And more surprising is the location of the hotspot. The peak intensity is very far to the right. High beam peak is average but it is very tiny and narrow. Width is also very poor and if you review the images again you will notice less light along the cutoff (on both sides) that tapers downward until intensity starts to pick back up.

    Unfortunately, this design by Hella is not a high performer. Which may be more a result of Cadillac and their input towards the design. This suffers from low power and with only 16.5W for the low beam it’s obvious they wanted to keep from having to implement a cooling fan. Perhaps car makers don’t want a part that could potentially fail? Although in all fairness there are other passively cooled LED projectors with similar power that produce more light and with only 1-chip!
    Last edited by evo77; August 6th, 2018, 05:57 PM.
    www.automotiveLEDresearch.com

    Comment


    • #3
      Awesome post as always.
      Passive cooling plus dedicated emitter for highbeam is

      Waiting for measurement

      Comment


      • #4
        Measurements are posted. Thanks!
        www.automotiveLEDresearch.com

        Comment


        • #5
          I have a feeling moar chips =/= better. A single chip, a single large optic, might be a more efficient way of going about it than a bunch of small low power chips and individual small optics.

          2000 Toyota MR2 Spyder
          2017 Lexus CT200h F Sport

          Comment


          • #6
            My only fear of more chips = more opportunities for failure. I'm also not a fan of the complexity. I think simplifying the electronics and leaving the complexity in the optics is the way. One big multi-die front facing chip and a projector looking optic to shape its beam. It has to be possible

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            • #7
              I'm guessing Koito patented their design, otherwise everyone else would be copying/trying to improve on that.

              Comment


              • #8
                Originally posted by evo77 View Post
                Unfortunately, this design by Hella is not a high performer. Which may be more a result of Cadillac and their input towards the design. This suffers from low power and with only 16.5W for the low beam it’s obvious they wanted to keep from having to implement a cooling fan. Perhaps car makers don’t want a part that could potentially fail?
                Could also be a case of cost-cutting. Would've cost GM more for a higher-powered,fan-cooled projector, then higher-output headlights would then necessitate headlight washers if GM follows ECE requirements for washers on headlights producing at least 2000lm
                Originally posted by HK45
                I don't even look to see what Eddie writes anymore. I'm too busy staring at his avatar.

                Comment


                • #9
                  Originally posted by Eddie View Post
                  Could also be a case of cost-cutting. Would've cost GM more for a higher-powered,fan-cooled projector, then higher-output headlights would then necessitate headlight washers if GM follows ECE requirements for washers on headlights producing at least 2000lm
                  Yes, could be the case. Although the Koito biled is just shy under 2000 lm but yet still delivers very respectable output.

                  I do agree that 1-chip/1-lens designs seem to fair better in overall output/performance when compared to multi-chip ones but perhaps the flexibility of tailoring a specific beam pattern to the client is why they opt for the latter.
                  www.automotiveLEDresearch.com

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                  • #10
                    Our performance metrics are very different of those from OEMs. For example I saw a video on the various versions of the Q5s.... one of them had a 1000 lux hot spot on Lightwerkz wall test compared to like 500 or so for OEM. Almost certain such brightness is illegal. But then, so is retrofitting...

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                    • #11
                      There is no US max intensity for hot spot. But there is for high beam (75,000 cd).
                      www.automotiveLEDresearch.com

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                      • #12
                        I think hella made this light as halogen lights - more intencitive in center, but this is compensated if the module is AFS.

                        https://www.youtube.com/watch?v=N2oPWCOBGLE
                        Not usual LED retrofits:
                        Swift with DRL,
                        Nissan Note with corner light,
                        Mazda CX-7,
                        Mercedes W211 E-Class

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                        • #13
                          Great share!

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