20-20 NIGHT VISION

Night vision diminishes as eyes age; new technology helps older drivers see better after dark, reducing the risk of accidents

by Peter duPre

It is said the eyes are the windows to the soul. While that may or may not be true, one thing for sure is our eyes are our windows to the world.

Virtually everything we do – from work to play – is dependent upon our having good vision.

Good vision is especially important to those involved with heavy construction who work outdoors while spending a lot of time behind the wheel of their pickups getting to and from jobsites.

The problem is our night vision degrades with age without us even realizing what’s happening; you may have 20/20 vision during daylight hours, but after dark the eyes just don’t see like they used to when you were younger.

That’s when impaired night vision becomes a real safety issue.

According to the National Safety Council, traffic deaths at night are three times greater than during daylight hours.

So what makes driving at night so dangerous? Ninety-percent of a driver’s reaction to a given situation depends on peripheral vision, depth perception and color recognition – all elements that are greatly reduced at night, slowing down reaction time.

A driver’s reaction time can be the difference between an avoiding an accident and being in one.

“Nighttime driving is particularly hazardous to all drivers because the human eye is designed to work best during daylight” says Dr. J.P. Wong, a Seattle area ophthalmologist we contacted about night vision and how it affects middle-age drivers.

During daylight, the eye’s iris closes down – like a camera lens in bright sunlight – making a very small opening to let in the bright light and providing a good depth of focus.

At night, the iris opens wide to let in more light, which has the effect of focusing the light over a larger area of the retina, making it more difficult to focus on objects.

Tools for improving your night vision include a brimmed hat and polarized/UV protective sunglasses for daytime use, so the eyes don’t get fatigued. Tinted or clear night-vision eye glasses reduce glare and increase contrast, allowing you to see better in the dark.

That, in a nutshell, is why older drivers are often taken unawares by driving at night; during the daylight hours they see just fine, but after dark driving becomes more of a challenge with objects not being in sharp focus, or glare and halos forming around pinpoints of lights.

This means that dangers such as pedestrians, animals, road hazards and other vehicles are often not seen until it is too late to react in time to avoid an accident.

Small fleet owners report that the average age of their drivers is hovering around 50-years old.

That means that virtually all fleets are exposed to increased accidents due to hampered night vision, resulting in property loss, employee hour loss, and increased insurance rates.

So what is a small fleet owner to do?

According to Troy Bedinghaus, O.D., a practicing ophthalmologist in Lakewood Ranch, Florida, the number one thing to do is to make sure drivers over 40 have an eye exam by a certified ophthalmologist at least once every two years to check for night vision acuity.

If your eye exam shows there is a diminishing of good night vision, there are a number of corrective lenses (clear or tinted) that can be used to bring night vision back to where it should be for safe driving.

The newest lens technology, called Wavefront, is also something to consider. It uses a laser to “map” each eye and matches your glasses accordingly. Very cutting edge, but also said to be very good for maximizing night vision.