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Why do Yellow Tinted Glasses 'Brighten' view?

  1. Nov 29, 2008 #1
    I live in Seattle and bought some of those tinted yellow glasses and they really seem to brighten up my view, almost as if more light is reaching my eyes.

    I've read other people who say the same thing, so I know it just isn't my perception.

    I am quite curious, can anyone explain the Physics of why this would be ?
  2. jcsd
  3. Nov 29, 2008 #2


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    Human eyes are more sensitive to light in the yellow part of the spectrum. The glasses reduce the total light reaching your eyes, causing the pupils to dilate, to let in more light. But the light blocked by the glasses is in the spectrum at which the eyes are least sensitive to begin with, So more yellow light reaches the retina.

    This same thing caused problems with older cheap sunglasses. They blocked light, causing pupil dilation, but they didn't block UV. The upshot was that the dilated pupils let in more of the unblocked and dangerous UV.
  4. Nov 30, 2008 #3
    Thank you for the thorough explanation. Can I conclude that the same 'dangers' of the cheap sunglasses would also apply to these glasses or do you think they block UV ?
  5. Nov 30, 2008 #4


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    Some yellow-lensed glasses, like decent shooting glasses, have UV coatings and are safe to use. If you bought inexpensive glasses, they are probably not UV coated, and are NOT safe to use. The glasses should have been prominently tagged with a statement about how much UVA and UVB they block.

    For this same reason, do not buy children sunglasses (no mater how cute they look) unless you are confident of the UV-blocking capability. This is especially important if you and your child are going to be around water, sand, or snow, which all reflect UV.
  6. Nov 30, 2008 #5

    you mean the 'blue blockers' that they used to sell? blue blockers do more than 'brighten' things. they make everything seem more colorful. its amazing. you really have to see it to believe it. when you take them off everything seems washed out. colorless. grey.
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