It’s very easy to get confused about which is which and why it matters.
They sound similar, but when you look at the science behind what’s going on, they are quite different.
Let’s look at a simple overview of each, along with some everyday examples you will be familiar with.
Reflection occurs when a beam of light hits a reflective surface at a particular angle and “bounces off” or reflects. The light enters the material at an angle of 45 degrees and is reflected back at 45 degrees. This is exactly what happens when you look in the mirror, in a shop window or another reflective surface.
It is a very useful physical phenomenon, particularly when used in safety clothing or vehicle safety stickers such as Chapter 8 chevrons. In these cases, specially reflective materials are used to reflect the light from cars and surrounding lighting to ensure people and their vehicles remain safe in situations where otherwise they would be almost invisible in the dark or bad weather.
To see a great example of how reflection can be used to ensure vehicle safety, take a look at https://www.vehiclechevrons.com/.
Unlike in reflection, the light does not bounce off the material in refraction. Instead, it enters the material where it is bent due to the change in density from air to the material or from one material to another. It occurs because of a change in the speed and the wavelength of the light waves travelling in the different materials. You can see more examples and illustrations of reflection and refraction in action at https://www.britannica.com/science/light/Reflection-and-refraction.
A good way to observe this simply at home is to fill a glass with water and place a spoon or knife inside it. When you view the object through the side of the glass, it will appear to have bent or broken. This is refraction in action.
The bottom line
Reflection happens when light interacts with materials such as a mirror or a safety sticker, such as Chapter 8 chevrons, when light enters and leaves the material at the same angle (45 degrees).
Refraction happens when light enters a material with a different optical density. The speed of the light wave is altered by the density and the light wave is bent.