Reflection vs. Refraction: What's the Difference?
Read the comparison below, or explore it visually. Create a visual lesson comparing reflection and refraction using available credits or plan allowance.
Reflection is light bouncing back from a surface into the same medium, while refraction is light bending as it passes from one medium into another. Refraction happens because light changes speed between materials, such as air and water; reflection obeys the rule that the angle of incidence equals the angle of reflection, so a smooth mirror returns a clear image.
At a glance
| Reflection | Refraction | |
|---|---|---|
| What happens | Light bounces back from a surface | Light bends as it enters a new medium |
| Medium | Stays in the same medium | Passes into a different medium |
| Speed of light | Unchanged | Changes, e.g. slower in glass than in air |
| Governing law | Angle of incidence = angle of reflection | Snell's law: n₁ sin i = n₂ sin r |
| Everyday example | Your image in a mirror | A pencil looking bent in a glass of water |
Which should you use?
Reflection explains anything that redirects light back, such as seeing yourself in a mirror, the shine of a still lake or a car's rear-view mirror showing traffic behind.
Refraction explains anything that bends light passing through, such as spectacles and camera lenses focusing light, or a swimming pool looking shallower than it really is.