How a graphic pattern cut in safety glass can draw forth a smile.
In our day-to-day lives most of us normally don't particularly notice the glass that surrounds us. Ever since the first window was mounted in the wall of a house, humans have been happy being protected from weather and wind, and glad to be able to work inside in daylight. Glass is a useful, practical and strong material, although sometimes glass is referred to and seen as being an obstacle, a barrier. Through introducing elements, which to the eye is seen as real, while the brain consciously knows it to be impossible, the viewers see things differently from what they are, or appear to be.
Kaleidoscope: Engaging the eyes
By varying the thickness of the glass in a regular pattern a kaleidoscope appears. Changing mass is all that is necessary to produce a kaleidoscope in an ordinary window. The shape of the refracting material, the thickness, and the index of refraction are the three things that determine the focal length of each optical phenomenon and by that what is perceptible to the eye.
