In embodiments of multi-wavelength infra-red LED, a mobile device includes a multi-wavelength infra-red (IR) LED that projects near infra-red (NIR) light in multiple wavelengths. The multi-wavelength IR LED can be implemented as a single LED, or as a combination of LEDs packaged together as a single component for implementation in the mobile device. The mobile device can be implemented for various IR-based features, such as for iris illumination and authentication, proximity sensing, gesture detection, and for other IR-based features that each correspond to a different one of the multiple wavelengths of the NIR light. The mobile device includes a NIR filtering system to receive reflections of the NIR light and filter the multiple wavelengths of the NIR light for each of the different IR-based features of the mobile device.