Abstract: The demonstrative meter of thermal expansion and contraction of solid is made of a metallic hoop and a metallic ball. In this paper, we introduce a new synthesis-demonstration meter of thermal expansion and contraction of solid based on more exploration of physical principle of the demonstration experiment, which uses the characteristic of thermal expansion contraction of solid as the switch of the passing or breaking to the laser circuitry, and also uses the amplification function of the light path to minim appearing the effect of the thermal expansion contraction. Different from the traditional meters, by using this meter, we have made a virtual improvement in both the notability of demonstrative effect and the possession of synthetic knowledge.

Key words: thermal expansion and contraction, phenomenon analysis, amplification function to minim, colligation demonstration.