Leakage amount detector with vacuum cavity and detection method thereof

The invention discloses a leakage amount detector and a detection method thereof. The detector comprises a differential pressure sensor and a controller. The differential pressure sensor comprises two gas input terminals, wherein one terminal connects with atmosphere, the other one connects with a vacuum cavity to be detected. The controller comprises a power supply module, a signal processing module, a processor and an alarm output module. The method comprises the following steps: the processor obtains a first pressure value of the vacuum cavity relative to the atmosphere through the signal processing module; after a preset time, the processor obtains a second pressure value of the vacuum cavity relative to the atmosphere through the signal processing module; the processor calculates actual value difference of the two pressure values of the vacuum cavity relative to the atmosphere; after comparing the actual value difference with preset pressure difference in the processor, the alarm output module sends a corresponding signal according to above comparison result. The leakage amount detector and detection method of the present invention have the characteristics of high measuring precision, simplicity, visualization, capability of satisfying large scale production demand and the like.