采用非接触式门铃设计，降低了接触带来的安全隐患——电路方案。

简介：
The circumstances surrounding Covid-19 have prompted a heightened awareness of health and well-being. Consequently, contactless doorbell systems represent an exceptionally suitable solution in this environment. The hardware components include: one bolt, one WiFi module, one LED (universal), one infrared proximity sensor, one buzzer, and one USB-A to Micro-USB cable. Remaining socially distanced is arguably one of the most effective strategies for avoiding COVID-19. I strongly recommend that you stay home. Even if we are unable to completely halt access to certain residences due to urgent situations. Upon approaching a house, the initial action involves searching for the doorbell button. However, traditional doorbell buttons pose a potential risk of disease transmission. Specifically, if an infected individual presses the button, the virus can remain present on its surface; subsequent contact by an uninfected person then facilitates its spread. Utilizing contactless doorbells effectively mitigates this very risk. These systems operate by requiring the visitor to position their palm near the sensor during a brief period. During this time, the sensor gathers recent data and compares it against a predefined minimum proximity threshold. If the reading falls below this established limit, an SMS notification alongside a buzzer alert is dispatched to the property owner. An LED illuminates when the sensor detects the presence of a hand near the doorbell.