Very simply put, an infrared (IR) receiver module is a component that receives an infrared signal from its associated transmitter and interprets the request. Infrared technology is prevalent in many fields and applications. These infrared signals are transmitted to and from the IR receiver module in wavelengths of 840-960 nanometers in the near infrared (NIR) range. The Infrared Data Association (IrDA) sets the standards for the use of infrared in wireless data communications.
Many devices use an IR receiver module for wireless remote control and similar purposes, such as in television remotes or robots. Applications that utilize this technology must consider factors such as line of sight, proximity parameters, viewing angles and interference from external infrared sources. Natural and artificial lighting emit infrared wavelengths, as does the human body, and electromagnetic noise is everywhere. IR devices must compensate for any of these types of factors to ensure that the module is able to function appropriately and consistently.
In television remote control applications, the remote sends infrared signals at a particular frequency, and the signals are received by the television. This frequency usually is set between 30 kilohertz (kHz) and 60 kHz, with the most common frequencies being 36 kHz, 38 kHz and 40 kHz. An IR receiver module in the television recognizes its preset frequency to the exclusion of all other frequencies.
Audio and visual devices generally utilize the same technology for their remote controls. IR extenders relay the signal from one IR receiver module to another. To avoid conflict among IR receivers that control different devices, slight variations are made in the bit rate of the transmissions.
Additional applications that utilize an IR receiver module include three-dimensional (3D) glasses, a plethora of sensors and various human-computer interaction (HCI) technologies. Sensors can be presence-based or proximity-based, transmissive or reflective. Driveway motion sensors are a prime example of presence sensors. A proximity sensor takes this a step further and calculates the approximate distance to a nearby object.
Blob detection, an area of computer vision (CV) that aims to identify specified points or regions, often uses an IR receiver module. HCI applications, especially as part of the Open CV library, utilize these modules in their development of technologies such as interactive whiteboards and face recognition. Robots need to be able to detect motion, identify visual data sets, detect an object without touching it and the like. Each of these desired features utilizes an IR receiver module.