Liquid helium-4 superfluid state temperature indicator and use method thereof

The invention belongs to the technical field of liquid helium-4 superfluid state temperature indicating equipment, and particularly relates to a liquid helium-4 superfluid state temperature indicator and a use method thereof. Comprising a container, an optical prism, a rotating shaft assembly, a supporting frame, an optical fiber connector for incident signals, an optical fiber connector for receiving signals and a frame. According to the mass balance principle and the Roll film principle in the helium-4 superfluid state, a rotating bearing device and an optical prism and optical fiber signal combination are arranged; when the temperature is reduced to 2.1 K or below, a common liquid phase is changed into a superfluid, and superfluid helium can move to the position as low as possible along the device wall, so that the liquid helium in the cavity with the high liquid level flows into the cavity with the low liquid level through the capillary tube, the mass of the liquid helium in the left cavity and the mass o