Infrared Sensor Technology in Automatic Devices:
The working of sensor-based devices has gained attention, highlighting the role of infrared (IR) technology and sensors in enabling touchless operations.
- Light is an electromagnetic wave consisting of oscillating electric and magnetic fields, capable of travelling even through a vacuum.
- The spectrum of light refers to the full range of electromagnetic waves arranged according to their frequency or wavelength. It includes radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.
- Humans can perceive only a narrow band of this spectrum (visible light), while infrared radiation lies just below red light in frequency and remains invisible to the human eye.
- Devices like remotes and automatic washbasins use IR LEDs (light-emitting diodes) to emit these invisible infrared waves.
- Detection is enabled by sensors called Photodiodes, which act as light-sensitive switches. When IR light falls on them, they allow electric current to pass, triggering a response.
- In automatic devices like washbasins, IR light normally does not reach the sensor; however, when an object such as a hand is placed nearby, it reflects the IR waves back to the sensor, thereby activating the system.
- Such technologies are widely used in automatic doors, escalators, dryers, and remote controls.
- The underlying science integrates concepts from Optics, Electromagnetism, Condensed Matter Physics, and Quantum Mechanics, where the interaction of light with electrons in materials enables precise sensing and automated responses.
