智慧感測器是智慧城市、工廠、製造、交通、農業、生活等的基礎，感測器偵測到的資訊，藉由網路傳送到雲端，可達到智慧、人性與節能等功能。但是，傳統的感測器除了尺寸限制外，也只能偵測特定的單一資訊，藉先進的半導體製程技術與電子電路技術的開發，感測器的資料處理能力和通訊技術明顯提升。本文介紹常用的感測器及其性能，將其應用在工業上高溫的射出製程及低溫的冷凍製程上的檢測，以達到製程監測、改善及品質保證等目標。

Smart sensors are the basis of smart city, factory, manufacture, transportation, agriculture and life. The sensor is able to detect the information of environment, and transmits to the cloud through internet for smart control. The traditional sensors are limited by their sizes and single-phase detection. However, through the development of semiconductor and electrical circuit technologies, the capacity of sensor is significantly uplifted. In this paper, the general utilized sensors and their properties are introduced. The applications on the process diagnosis of high-temperature injection molding and low-temperature freezing processes by ultrasonic technology for improvement of process operation and guarantee of products are also presented.