A tracker for a surgical navigation system and a surgical navigation system are provided. The tracker comprises a carrier and an electrical circuit disposed on the carrier. The electrical circuit comprises at least one infrared light emitting diode, IR-LED, and a battery or a wireless power reception device configured to receive power wirelessly, wherein the battery or the wireless power reception device is configured to provide power to operate the at least one IR-LED. The electrical circuit is configured to limit a current for at least one of the at least one IR-LED to not exceed 15mA.