Contactless Elevator Call Based on TOF Laser Ranging and Floating Image Technologies

Abstract

This paper introduces a method of applying TOF (Time of flight) laser ranging (TOFlrt) and floating image technologies for contactless elevator call. The first is to project the image of the elevator button into the air. The second is to touch the floating image with your finger to activate the TOF sensor to send a control signal to the elevator. In order to verify the accuracy and sensing range of the TOF laser sensor, a measurement experiment is carried out. The measurement results show that when the floating image height is from 30mm to 50mm above the device surface, the sensor can detect the finger accurately with low latency. This system has been successfully implemented to elevators in a number of office buildings in Shanghai and all implemented systems are currently in smooth operation.