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Thread: RLT Basics

  1. #1
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    Default RLT Basics

    RLT (Red Light Therapy) has helped some people with rosacea. However, there is quite a bit of confusion. So I will break this down.

    There are 3 basic parameters to consider:
    - Wavelength
    - Illuminance
    - Exposure Time

    WAVELENGTH
    ----------
    RLT with LED's comes in 3 typical wavelengths (or combination).

    - 660nm seems to be the most studied and most popular. It is a true red in color.
    - 630nm is probably the second most popular, but less studied. It is a red-orange color.
    - 680nm is a "deep red" and not as studied as much as 660nm, primarily because of cost. However, in theory, it has the potential to be more effective than 660nm. Recent LED technology has allowed the cost to come down quite a bit, but commercial products have not caught up.
    - Infrared light is at higher wavelengths. I am not going to discuss it because I believe RLT is more effective, but this is admittedly a guess. In fact, IR can be problematic for some people.

    ILLUMINANCE (LUX)
    ----------
    Illuminance is basically the intensity of the light. Unfortunately, you can not simply use the AC power a good indicator for the illumiance. This is because of various factors such as the power factor, LED efficiency, beam angle, area of the panel,etc. The best way to determine illuminance is to simply measure it (see next post). This eliminates all variables. Basically, what you see (or what the light meter sees) is what you get. Questions remain about illuminance, specifically as it pertains to rosacea. It is possible that for rosacea, illumiance should be lower than for other conditions. However, it is also possible that greater illumiance can be better. The goal of the community should be to collect information about various units so that one can best decide. In my opinion, the best device would be a high powered device that is dimmable to zero. Unfortunately, I do not know of a commercial unit that does this. But in time, I feel there will be.

    EXPOSURE TIME
    ----------
    We don't know the ideal amount of exposure time. But certainly the illumanice should balanced to the exposure time. One typical approach is to do a 15-20 minute session. This seems reasonable. Could longer or shorter sessions be beneficial? Perhaps, but we don't know. I have heard of people using RLT for well over an hour, but I do not know what the illuminance was so take that with a grain of salt. For now, a 15 minute treatment, once or twice a day is a reasonable baseline.

    SUMMARY
    ----------
    630nm or 660nm are common wavelenghts, with 660nm possibly being the preferred wavlength.
    We need to establish illuminace of various units. I will post some data. If you want to contribute, then see the next post.
    We know a typical exposure time.

    Let me add this. The cost that doctors charge for this are very expensive. Once the illumiance database is established, home units will be every good as a doctor unit.

  2. #2
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    Here is how to measure illuminance. Get a light meter on Amazon ($20)
    http://www.amazon.com/Dr-Meter-Light...dp/B004K0A7I6/

    Set it to "ON", not "H".
    Select the appropriate multiplier for the light source. You won't know the best selection ahead of time, but you should be fine with the "100000" setting. You can also use the "20000" setting. Just be sure to give me the number that the LCD reads and the multiplier that you use. But again, the "100000" setting should be adequate.

    Next, use the "head" and point it at the light source. Make sure it is the same distance that your face would be. Don't put it right up against the light. This is important. You can move it back and forth and bit to see the variation. Let me know what those values are.

    At this point, you will have established the Illuminance (intensity of the light) and we can compare it to other units. FOR REFERENCE ONLY, expect an LCD reading of about 8-60 when the multiplier is set at "100000".

    One minor note. If the LCD is reading less than 10 on the "100000" multiplier then switch to the "20000" multiplier. In other words, the intensity of light is quite low. This may be the case, but I would hope not. Go ahead and get familiar with the unit by putting it near a regular light bulb. Then when you get to the doctors office, you can quickly get the measurement. You can also measure your home unit in the same manner.

    ---

    Next is wavelength. Now, in reality you need an optical spectrometer for that. In general, these are very expensive although there are cheap DIY kits. But at the end of the day, it really doesn't matter too much. Here is why. RLT comes in 1 of 3 variations. 630nm, 660nm, and 680nm. If the light looks truly red, it is 660nm or 680nm. While I can tell the difference, you won't be able to. That is no big deal really and it is mostly likely 660nm. If the light looks more red-orange, then it is 630nm. So just look for something that is either a true red or not.

    ---

    There you have it. For $20 and a bit of knowledge you can determine what is being used. You can then compare to other units. One caveat is that if there is infrared, the light meter can not see that. However, in general, infrared is not recommended for rosacea. Most recommend, in order of preference, 680, 660, 630nm.

    One minor note. If the LCD is reading less than 10 on the "100000" multiplier then switch to the "20000" multiplier. In other words, the intensity of light is quite low. This may be the case for some of the lower powered units.
    Last edited by wiry; 30th April 2015 at 04:15 AM.

  3. #3
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    Default

    The goal of this thread is to characterize home and doctor office units. This is done by collecting information about wavelength (visual inspection and/or manufacturer data) and illuminance (via power meter).

    Please do NOT discuss whether RLT can help your rosacea,etc. We are only collecting the specs for units in this thread. The goal is to create a database in which you can compare units and make an informed decisions about them.

  4. #4
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    Caribbean Sun
    --------------------------
    660nm
    1,600 Lux at 4.0 inch


    DPL Deep Penetrating Light
    --------------------------
    630nm
    280 Lux at 4.0 inch
    This unit has only 10 red lights. 144 lights are infrared and do not show in the light measurements


    NORLANYA Photon Therapy - 3 Panel (Rebranded as other brands as well)
    --------------------------
    630nm
    5,700 Lux at 4.0 inch
    Light level can be reduced by covering with paper or tissue paper, if needed.


    Initial Conclusions
    --------------------------
    - The Caribbean Sun has a reasonable illuminance, but the 2 panels are relatively small and can not cover the entire face.
    - The DPL unit simply does not have enough red LED's.
    - The NORLANYA has a relatively large illuminance. It is at 630nm, which may not be as effective as 660nm.

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