Refraction is the tendency of light to bend as it passes from one medium to another, such as from water to air. Due to the different densities, light travels through various materials at different speeds.

For example, light passes through the air at a faster rate than through water, so when light enters the water, light enters at different angles. Of course, it does not enter at an angle of 90 degrees, just like when the sun is shining.

Therefore, for the diver to see clearly under water, we wear a mask. Now light must travel from water, glass and air to our eyes. During each pass, the light must bend and form through each medium before we see the object. Therefore, the object will be closer to us at a ratio of 4:3 than the actual size. This means that objects 4 feet away look only 3 feet away. This is why it is difficult to determine how far an object is from you as a diver, as described below…

What is refraction and visual reversal? was originally published on Spring