Lyman diopter shooting aid

[Flash]

I purchased a box lot of gun goodies and inside was one of these shooting aids. For anyone struggling with failing eyesight and those that wear lineless bifocals, this concept is for you. When I shoot with open sights, either the target or the sights are in focus but not both. There was a time when open sights were my friend but now with having to wear glasses, a scope is my savior. I attached this to my eyeglass lens and WOW. The aperature forces your eye to focus again, when it normally wouldn't. The same effect can be duplicated with tape on the lens of your glasses but my point is, this really works and works well.

[Glanceblamm]

You can also get your eye's (LAZED) but for some, the risk of permanet loss of the periprial vision happens 
 
Used to be an advertiser right here at GBO "Clear2target" that would sell static cling disk's for the eye glasses but I believe they have been shut down because of an infringement.
 
The principal is very sound like you say though and a piece of electrical tape works well to try this out.

[Savage]

I'm sure they work well for target shooting. Other than sighting in, I rarely shoot at bullseyes. I would imagine such an optical device would limit peripheral vision needed for action pistol sports.
Savage

[Flash]

I'm sure they work well for target shooting. Other than sighting in, I rarely shoot at bullseyes. I would imagine such an optical device would limit peripheral vision needed for action pistol sports.
Savage

Not necessarily. I've tried it with a piece of tape, smaller than a dime. I used a 41 magnum case for a punch and cut a dot of tape on a kitchen cutting board. An Exacto knife was perfect for a small hole and I stuck this to my glasses. What a difference it makes and target aquisition isn't an issue either.