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Rainbow in your hands
After rain, we can see a beautiful rainbow in the opposite direction
of the sun.
Usually we cannot see a rainbow without rain.
But we can see one at any time, if we understand the principle of rainbow.
We use glass beads or plastic beads instead of rain. We stick glass
or plastic beads with paste on a black paper and set the paper in a frame
like a picture.
When we have our backs to the sun, we can see a rainbow in the frame.
These glass beads are used in Japan for traffic indications like pedestrian
crossing.
It is easy to see the traffic indications even at the deepest hour of night.
We are indebted to these glass beads for this.