This Tuesday I visited the University of California, Berkeley. I had an excellent afternoon running an outreach workshop with the kit that I am touring.
With a group of 8 graduate students we explored 3 different themes of photonics, i.e. the science of light (photons). We used hands-on experiments to experience scientific phenomena on mirrors & reflections, the electromagnetic spectrum and telecommunications. Easier possibly shown in video.
Mirrors can be made to create illusions. The Secret Savings box is not magic. The floating ball is actually half a ball stuck on a diagonal mirror. The other half of the ball is a mirror image. The coin disappears behind the mirror when dropped in the top of the box.
White light isn't white. Right? We see it in rainbows, where sun light can be split into red, orange, yellow, green, blue, indigo, violet, ... This is the visible light of the electromagnetic spectrum. This plastic sheet is a diffraction grating, a rainbow maker. The plastic has thousands of lines engraved in it, a grating. The grating splits the different colours of the light by changing the direction of travel of each different colour. Gratings can be used to filter light, reflect it, block it, or make it change direction.
Light travels in a straight line, but it can be made to bend and change directions in materials such as glass or plastic. This effect is called total internal reflection and is the fundamental principle of operation of fibre optics. Fibre optics are strands of glass that physically connect the world to carry messages and information, in the form of light, and are the skeleton of the internet.
I hope you get the feeling that these are very hands-on demos!
One important point was raised during the workshop. It remains a challenge to explain the scientific intricacies to a public that is not familiar with the underlying science and applications. That is where the practical experiments come in handy, as experiencing these effects can lead to questions and richer engagement. I, the researcher, can inform and help my audience form an opinion on the subject matter and broaden their horizon.
I am very grateful to Stephan, Joe and Mimi from the University of Southampton’s ILIAD team for the help in making these Vine clips and setting up this Tumblr page with more examples of hands-on optics experiments.
Thank you again to the UC Berkeley Photobears Society for the warm welcome and hospitality.
Comments open for discussion.
