Star Light, star bright, are you a fan of Coherent Light?

Lasers are sources of coherent light – all of the light waves are aligned with each other, therefore producing a stronger and more concentrated beam. Unlike “normal” white light, which spreads out in all directions, laser beams will continue to travel in straight lines until they collide with another object or particle. In general, there are not enough particles present in air to reflect laser light. However, when a substance such as chalk dust is added to the environment, the light waves bounce off of the tiny powder particles, reflecting them in multiple directions. Our eyes can then perceive the light. My goal with this picture was to create some kind of geometric shape by reflecting a single laser beam off of multiple mirrors. Setting up the mirrors was definitely the trickiest part, because the angles of reflection all depend on one another – moving one mirror changes the entire shape! The wide background glow behind the beams was originally unintended, but ended up coming from the camera’s flash reflecting off of the copious amounts of chalk dust used.

Sarah Brown
John Abbott College, Ste. Anne de Bellevue, QC
Second Prize ( High School Individual Category )
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