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"What eyewear do you use for hunting?"

Stuart Quam, O.D.

Every hunting season we see patients who have injuries related to being out in the field without protective eyewear.  Protective eyewear is so important that it’s one of the main things I will not go into the field without.  I look at three areas when considering what to protect my eyes with in the field.  This is a personal preference, since it depends on the conditions, prescription needs, and the person’s tendency toward photophobia (light sensitivity).

Protective properties of eyewear are the most important aspect on the list. The impact resistance, UV protection, and frame/lens coverage are three to consider. I like Polycarbonate or Trivex lens materials as they are renowned for their impact resistance. Both are very difficult to shatter, which is critical in preventing sight-threatening damage to the eye.  As an added bonus, these two lens materials have an inherent property to block UV 400 and shorter light waves, which I will touch on later.  Last is to have a frame that is larger or wrapped to ensure proper coverage of the eyes.

The tint in your lens is also quite dependent on personal preference. In order to talk about how tints work, we need to know a little about light.  For this, I have a line graph showing wavelengths of light and the relationship to color. Tints work by blocking certain wavelengths of light. This is where it can get confusing. First, we want a lens that will block the UVA and UVB wavelengths for protection. This can be accomplished with a clear UV 400 coating, polycarbonate, or trivex lens. This means that even completely clear lenses can have UV400 protection. The tint color and darkness depends on the conditions and how light sensitive a person is.  For hunting, a person that is not very sensitive to the light may use a yellow or orange tint versus a darker green tint for someone that is very sensitive.  I have mentioned these three tints as they block a portion of blue wavelengths which are one of the main causes of glare. The reduction of glare and increase of contrast will give you a feeling of brighter, clearer vision.  This is not to be confused with ‘blue-blocker’ lenses which block up to 500nm, but tend to alter natural colors.

Lens optics is the last item on my list. Ophthalmic lenses are given what is known as an “abbe number” to indicate how clear the lens material is when compared to one another. Polycarbonate has an abbe number of 32, while trivex has a rating of 43. This indicates that the trivex is slightly clearer optically.  Ophthalmic lenses are usually not stamped out like the lesser expensive lenses, which definitely provides better optics.  Adding Antireflective (AR) coating to a lens is another consideration to increase the optics of a lens. This coating can be applied to most lens materials. It decreases the reflections, increases contrast, and allows more light to enter the eye, resulting in clearer vision.

The following is a list of my eyewear that I typically take into the field.  First, a pair of eyewear with clear trivex lenses with AR coating for low lighting conditions. Second, a pair with Autumn Gold trivex lenses and AR coating for overcast hazy days.  This is a yellow lens that darkens to a subtle yellow brown when exposed to sunlight, which is a nice lens to boost the brightness on hard-to-see days.  Third, a pair with Neox lenses in polycarbonate material, (not available in trivex) with AR coating. This is a green lens that darkens when exposed to brighter conditions. I like this lens for sunny days with or without snow. I make sure all of the frames that I use are larger and have some wrap on them for full coverage. I pick this particular combination of eyewear because I have correction for distance. If I did not need correction, I would consider an interchangeable lens system that had a frame with similar tinted Polycarbonate or trivex lenses.

So don’t forget your safety eyewear when you head out to the shooting range or the field this year. Also remember that when working in the garage or in the yard, eye protection is always a good idea. Be Safe.