Side-view 940nm infrared LED for diffuse sensing
The IR12-21C/TR8 is an infrared LED in the Everlight IR12-21 base family, packaged as a 2-SMD no-lead side-view device designed to mount flush against a panel or board edge with the optical axis bent 90 degrees outward. That orientation is what makes it work for reflective object detection, optocoupler pairing, and any design where the LED must fire sideways rather than perpendicularly off the board surface. Wavelength is 940nm — the standard near-IR peak that sits outside the visible band, so the emission is invisible to the human eye and aligns with the response peak of most silicon phototransistors used in proximity sensors and optointerrupters. Minimum radiant intensity of 0.5mW/sr is specified at 20mA drive current.