1. Registering for the Forum

    We require a human profile pic upon registration on this forum.

    After registration is submitted, you will receive a confirmation email, which should contain a link to confirm your intent to register for the forum. At this point, you will not yet be registered on the forum.

    Our Support staff will manually approve your account within 24 hours, and you will get a notification. This is to prevent the many spam account signups which we receive on a daily basis.

    If you have any problems completing this registration, please email support@jackkruse.com and we will assist you.

Photobiomodulation & Flicker

Discussion in 'Ask Jack' started by Jamie Ward, Feb 4, 2019.

  1. Jamie Ward

    Jamie Ward Gold


    Flicker can be measured with various metrics. One is flicker %, which is what you mentioned in Q&A. This measures what % the light intensity drops relative to the max light intensity. 100% flicker implies it is turning on and completely off.

    If you have a photobiomodulation device (such as the bed, which we have same as you) that has a programmable frequency is the relationship as follows:

    The flicker meter gives frequency, which approximately matches with the programmed frequency on bed, i.e. 2Hz on bed settings and 2Hz is displayed on flicker meter.

    The flicker meter gives c. 98% flicker. I assume this is because the programmable frequency on the bed is binary. i.e. at 2 Hz it is turning on and off at a frequency of 2Hz. This would make sense that the meter essentially says (almost) 100% flicker as it turns completely off momentarily.

    Even when ramped up to 9999Hz the flicker % is the same.

    At what Hz, should one not be concerned with flicker? Same question for the lower end? They design the flicker in for absorption but at what frequencies is flicker causing more harm than good?

    Thanks Sir.
    Karen & Glen C. and Joe Fang like this.
  2. Jack Kruse

    Jack Kruse Administrator

    It is not that easy......the ballast has a big effect and so does wiring. Youre at a 50 Hz cycle and Im at 60 Hz. I have found some interesting things with flicker at both cycles and I think 50 Hz in EU = why EHS is so much more common there.
  3. Hi Jack,

    In the UK, we have 60hz mains. Parts of EU have 50hz
  4. Jamie Ward

    Jamie Ward Gold

    UK is 50Hz...

    Ballast/driver is always what is responsible for the flicker. UK lights flicker frequency is almost always 100Hz on any that I have tested, which makes sense that as it is a harmonic of 50Hz (especially worrisome given Doug Wallace's mitochondrial research).

    So, with a programmable device such as one of those beds that let you choose up to 9999Hz (which my meter shows being closer to 8,500Hz), then a 100% flicker on that is not comparable to 100% flicker on a 100Hz device. Do you agree?
  5. Jack Kruse

    Jack Kruse Administrator

  6. Hey Jack & Jamie,

    Please accept my apologies for butting in with incorrect information.
    I could have sworn uk was 60hz, but I was wrong.

    Thanks for correcting me.

Share This Page