Diopter Devices Aid Older Eyes

Those of us over-40 types can use some help when shooting iron sights. As one gets older, your eyes lose the ability to rapidly adjust to different points of focus. In practice, when shooting a rifle, this means the target image may be sharp but the sights are blurry, or vice-versa. Or you may be able to see the target and front sight reasonably well, but the rear sight is a complete blurr. (That is this Editor’s problem when shooting a rifle, such as a Swedish Mauser, with a notched blade rear sight.) Even if you are using a rear peep sight, you may see a blurry rear circle (or two circles if you have astigmatism). Placing a diopter on your shooting glasses can help many people see open sights better, when shooting both handguns and rifles.

Merit Corp. in Schenectady, NY, offers an adjustable metal diopter that attaches to shooting glasses with a rubber cup. Though primarily intended for pistol shooters, the Merit diopter can also be helpful when shooting rifles with open sights, such as military bolt actions. Priced at $65.00, the Merit device features a shutter-style adjustable aperture iris.

Merit explains: “The human eye, whether or not prescription glasses are required, cannot focus on both sights and the target at the same time. The eye will constantly shift focus from the sights to the target trying to ensure proper alignment. Unfortunately, as we age, the eye loses the flexibility which allows it to do this; thus, sights and target begin to grow fuzzy. There is a simple way to combat this by increasing your eyes’ depth of field (range of focus). If you look through an aperture or pinhole of the correct size, you will be able to see both sights clearly, and the target will be clearly defined as well.”

In addition to diopters for eyeglasses, Merit produces a variety of adjustable iris sight products for rifles, including the Variable Iris Aperature for AR15s. Visit MeritCorporation.com or call (518) 346-1420.

Cheaper Diopter from Lyman
If you can’t afford a Merit adjustable diopter, Lyman offers a similar all-plastic device for under $20.00. The Lyman Hawkeye Shooting Aid mounts directly to your eyeglass lens with a rubber suction cup. The diopter section is made of plastic, and aperture diameter is non-adjustable.

Though it is simple and inexpensive, the Lyman Hawkeye works for many shooters, if positioned properly. (Don’t think this is anything close to the Merit Diopter in quality though!) Currently, Cabelas.com has the Lyman Hawkeye on sale for just $12.88, item # IK-229094. MidwayUSA sells the Lyman Hawkeye for $18.99, item # 936878. One MidwayUSA customer reports:

“This thing really works! I have it on my shooting glasses, and it has made a significant improvement in my ability to keep the front sight and target in focus at the same time. If you are older and find that you are having a hard time keeping the target in focus over ‘iron sights’, then this may be the answer to your problem. Mine works equally well for both pistol and rifle, although I do have to change the device’s position on my shooting glasses when changing weapon types.”