DATE: July 24, 2019
A mask is an essential equipment of snorkeling as it allows you to explore under the water clearly with your eyes. People who have tried looking under the sea without a mask know how difficult it is. No matter how clear the water is, everything seems blurry. The reason behind this is that we need light to see things clearly, and light under the water behaves differently as compared to air, which blurs our vision.
The optical ability of humans is the outcome of the complex interaction between the eyes, brain, and light. We can see because light from an object travels through space and reaches our eyes, where the irises control the intensity of the light by contracting and dilating. Our lenses and corneas bend the rays for our retinas, which turn the light into electronic signals. After that, these signals are dispatched to the brain, which decodes the information to detect the movement, appearance, and location of the object we are looking at. Then it bends the light waves back into the right position to put the picture on the retina. If the position is not correct, the eyes won’t be able to focus and everything we see will look blurry.
Moreover, light travels in a broad spectrum of electromagnetic waves. Due to its broadness, we use part of that spectrum to see things, which is called visible light. This light is affected by different mediums through which it travels. The medium in which light travels should be dense because it helps provide a dramatically clear effect. When you go snorkeling, the rays of light travel through three different mediums to reach your eyes. From the air, it enters the water, and from water, it enters the glass of your mask. This means that the velocity decreases three times while passing through those mediums as the light waves bend at the boundary between the two mediums, thus reducing velocity. This bending is known as refraction.
A snorkeling mask has air in the gap between our eyes and the glass. Therefore, the light rays first bend at the border between the water and the glass and then again at the boundary between the glass and air. This bending is sufficient to get the image positioned correctly on the retina and allows the eyes to focus underwater.
Another important point regarding focusing underwater is the refraction from air to water. While we are snorkeling, the water continuously moves around us, which allows light waves to bend in multiple directions at the same time. This can hinder or restrain the ability of the eyes to focus underwater. Therefore, it is crucial to wear a mask during snorkeling or diving underwater as it allows you to see things clearly. Even if you wear spectacles due to weak eyesight, you can go for snorkeling because some manufacturers produce diopters, which can replace your existing glasses while snorkeling or scuba diving.
Hence, whether you are a person with weak eyesight or a perfect 20/20 vision, you should always make the best of snorkeling, and that can only be done through wearing a snorkeling mask.
CATEGORY: The knowledge Reef