Letter Re: Multi-Lens Eyeglasses Sets

James,

I have a concern with the recently mentioned “Multi-Lens TEOTWAWKI Vision System“. I have not been able to find anything where they ask for a person’s pupillary distance (PD). This is necessary to ensure the optical centers of the lenses align with the wearer eyes properly. If you have ever looked through a binoculars that were dropped and had the the internal optics misaligned that will give you an idea of what misaligned optical centers can do. A way to measure your PD is discussed here.

People purchasing that kit should be aware that they may not work for them if the lenses are designed for their particular PD. This is more likely to be an issue with the higher powers than with the lower powers. I would advise them to try them as soon as they get them. If they can’t wear them for a day without eye strain of if they cause any double vision then they will not be of much help and should be returned.

I’d also like to mention that if you want to get your PD from your eye doctor ask them before the exam. Contrary to the link posted and this video it is usually recorded when fitting the glasses, not during the eye exam. – Eye Doc in Indiana