How do Polarized Sunglasses Work

Polarized sunglasses are designed to reduce the glare caused by the reflection of sun rays, particularly from the horizontal planes like water, snow, flat road and car hood. Previously, they are used commonly by fishermen and boaters as a means to minimize or block the glare reflected from the water surfaces. In recent times, as people have become more aware about the various benefits of polarized lens, goggles and sunglasses with polarized lens have gained extreme popularity, especially while spending time outdoors. Those who have vision problems or are sensitive to light can also benefit from the polarized sunglasses.

Working of Polarized Sunglasses

In order to understand the working principle of polarized sunglasses, let's discuss in brief about the reflection of light from the plain, smooth surfaces. When light falls on a flat and smooth medium, the reflected light is directed in the horizontal planes (polarized), rather than dispersing or scattering in all directions. The horizontally oriented reflected light is experienced as annoying flashes of white, known as glare. A prolonged exposure to such light intensities may result in temporary blindness.

In polarized sunglasses, a special filter is used that helps in eliminating the reflected light of high intensity or glare. In other terms, this polarized filter allows passing only a portion of light having wavelengths that are not aligned with the particles of the filter. Speaking about the composition of polarized filters, they are made up of chemical compound coated on a transparent glass or plastic lens. The chemical film consisted of tiny molecules that align in a parallel fashion with respect to one another.

If the chemical film is coated uniformly on the lens, the molecules absorb the entry of all light intensities that matches their alignment. Since glares are mostly caused by the horizontally oriented light waves, polarized sunglasses are designed in such a way that they allow passing of only vertical polarized light. With such polarized sunglasses, the texture and shape of objects become more clear, irrespective of the glare. This way, polarized lens reduces the glare effect. One of the drawbacks of polarized sunglasses is that liquid crystal displays (LCD's) may not be visible while viewing at specific angles.

Polarized Sunglasses: An Overview

The difference between normal sunglasses and polarized sunglasses is that in normal type, the intensity of all light spectrum is reduced equally; whereas, in case of polarized type, selective glares that cause annoying effect to the eyes are eliminated. You can also check whether sunglasses are polarized or non-polarized by rotating the sunglasses in different angles. For doing so, hold the sunglasses and focus on a reflective surface. Rotate the sunglasses slowly; if the intensity of the reflected light remains the same, then the sunglasses are not polarized.

Polarized sunglasses are available in a wide variety of frame style and lens colors. In addition, you can also opt for the prescription polarized lenses that are available in gray or brown color. If you are out for biking, driving, boating, skiing, golfing, jogging or other outdoor activities, then you will really appreciate wearing polarized sunglasses. While purchasing the polarized lens goggles or sunglasses, always opt for the superior quality from a reliable brand. Otherwise, a poor quality polarized lens may not be effective in elimination of reflected glares. In addition, you can also check other features like ultraviolet light protection, tinting, anti-reflective and anti-scratching coatings.