LED Head lights

  • olduser's Avatar
    I noticed this on the BBC news
    https://www.bbc.co.uk/news/articles/c3rlrz7rgw0o

    The suggestion is the modern lights are too bright.

    Whilst the perception is the lights are too bright, I believe what is as actually happening is different.

    The problem is the reflectors are able to work more efficiently because the LED light source is smaller than the old filament light bulb, this enables the source to be positioned closer to the focal point of the reflector.
    This results in a sharper cut off of the beam at the edges and top.

    With a larger light light source, (physically larger filament bulb) the edges of the beam gradually faded away because the reflector was unable to control it as effectively.

    It is this sharp change from dark to light that troubles our vision, even from inside such a vehicle the sharp cut off is a problem, it shows on dipped beam most dramatically, because the cut off is so sharp the driver fells the dip is excessive.
    On main beam, the night feels to be darker due to the sharp contrast between the illuminated area and the dark.
  • 3 Replies

  • Drivingforfun's Avatar
    I don't disagree with your theories but I think there's a simpler reason which is that people don't adjust the angle of their lights, which is far more important with LED lights (in part for the reasons you describe) than with old lights

    I'm aware everyone is affected differently and can only speak for myself but I actually find the trade-off (of being allowed to have LED lights myself but having to put up with others') well worth it

    One thing I do notice is that LED lights create a blue hue on the outer edge of the light beam ... I don't know the science behind it but I do occasionally see LED lights in the corner of my eye or in my mirrors and mistake them for an emergency vehicle
  • olduser's Avatar
    I don't disagree with your theories but I think there's a simpler reason which is that people don't adjust the angle of their lights, which is far more important with LED lights (in part for the reasons you describe) than with old lights

    I'm aware everyone is affected differently and can only speak for myself but I actually find the trade-off (of being allowed to have LED lights myself but having to put up with others') well worth it

    One thing I do notice is that LED lights create a blue hue on the outer edge of the light beam ... I don't know the science behind it but I do occasionally see LED lights in the corner of my eye or in my mirrors and mistake them for an emergency vehicle

    High intensity LED's do tend to have more blue in their output, if remember correctly white light is a blue LED with a coating which causes some of the output to be modified resulting ln a near white light but this reduces the total light output, less coating gives blue white light.
    Users are said to associate blue with modern, scientific or clean.