Describe the construction of kaleidoscope

A kaleidoscope is composed of a hollow tube. Three mirrors are placed in the form of a triangular tube and their reflecting surfaces face each other. One end of the tube is covered with a transparent sheet and another end is covered with an opaque sheet ... These patterns are formed because of multiple reflections.

Three rectangular mirror strips of dimensions 15cm x 4cm (length is 15 cm and breadth is 4 cm) are joined together to form a prism as shown. This prism is fixed into a circular cardboard tube. The circular cardboard tube should be slightly longer that the prism. This circular tube is now closed at one end with a cardboard disc. This disc has a hole in it through which we can see. At the other end of the circular tube, a plane glass plate is fixed. It is important that this glass plate touches the prism mirrors. On this glass plate, several small and broken pieces of coloured glass are placed. This end is now closed by a round glass plate allowing enough space for the coloured glass pieces to move.

Kaleidoscope operates on the principle of multiple reflection.

Construction of a kaleidoscope:

1. A kaleidoscope is constructed using three narrow strips of plane mirrors inclined at angles of 60° enclosed in a tube.

2. One end of tube has a ground glass plate with a clear glass plate on its inner side.

3. A metallic ring separates the two plates and the space is filled with coloured pieces of glass or broken bangles.

4. A cardboard with a hole in the centre is fixed on the other end of the tube.