Diffraction of Light ,Interference of Light
Diffraction of Light
The wave is transmitted to behind the obstacle when the wave passes through the medium. Please see also Fig.Interference of Light
In this case, interference is to be a new wave by overlap of multiple waves. When these waves have High correlativity, interference appears strikingly. Such waves are waves from the same source. In other case, these waves have waves with a frequency equal or close.A familiar example is bubble. It looks various colors. But in fact it is clear. It happened because the light reflected on the film front and behind the reflected light interfere.
◎【Video：a Bubbles】
・・・You can see the color like a rainbow on bubble
◎【Video：Grating sheets】
・・・A grating sheet is a transparent sheet put countless fine regular grooves. Light pass the grooves. The light diffract and interfere with each other. And the light looks rainbow color.
◎【Video：Pigment sheets】
◎【Video：Back of the CD】
・・・ Back of the CD looks like rainbow color. Because carved fine grooves there.