Controlling Light Reflection
When beams of light hit a pool of water, they produce beautiful, seemingly random patterns on surrounding surfaces. This "caustic" effect is well-known and easy to observe. This effect, which is very mobile and dynamic in liquid, produces static patterns with solid transparent materials such as glass or transparent acrylic. Scientists at Switzerland's Ecole Polytechnique Federale De Lausanne (EPFL) have developed an algorithm to control these patterns and organize them into coherent images. The work could open the door to interesting new applications in architecture as well as in automotive lighting.
Transcript
00:00:06 So This research is about cosics uh cosics are light patterns that are created when light is focused by a reflective or refractive surface such as a polished piece of metal or um some transparent material like glass um and typically these patterns are very random kind of chaotic and our goal was to um tame these kind of wild and intricate patterns and produce cosics of arbitrary
00:00:30 Imes so in our invention you can take some kind of image as a goal for example a portrait or a landscape scene and we will create a 3D surface out of for example transparent material like this that is formed in such a way that the light is focused to create this image so you could think of it as painting with light if you will through the form of an object so there is nothing embedded in
00:00:52 this surface that would create the image it's purely the way that light is refracted through the curved surface on on top of this piece of glass so so in computer Graphics we've studied for a long time the interaction of light um with 3D objects and how we can simulate that um in our project we want to invert this process so we are given the desired costic image and the goal is to find a
00:01:14 3D surface like this one that creates this image by focusing or diverting light um and we formulated that in a mathematical model and devised an algorithm to do this kind of optimization so in this project we actually teamed up with Architects and we're primarily looking at how to use this technology in architecture and one could for example imagine the window of
00:01:34 a storefront where the window is shaped in such a way as to create a costic image on the floor so for example if you take this object here you could see that if the Sun is at the right spot you create this portrait at the at the window and as the sun moves the image will change and evolve and it's a very kind of dynamic and fluent effect um but beyond these type of uses in
00:01:54 architecture you could think of many other applications for example in product design um any object that is composed of a reflective or refractive material could be interesting for this type of application so for example a wine glass a perfume bottle um jewelry U furniture all these objects that have shiny surfaces um could be manipulated in such a way as to create these images
00:02:17 um there's also more technical applications for example in reflector design um if you want to optimize the the way that light is used for example for a car headlight so that it's moved to the right spot on the street you can use similar techniques than the one we have invented um personally I'm quite interested in in art um so I'm looking into a dialogue with artists because I
00:02:41 think this interaction of light and form can be really very intriguing for artistic expression