Tracker with switchable radiation characteristics

A surgical navigation system comprising:

• a tracker comprising a first switch configured to be operated between a first switch configuration and a second switch configuration, the tracker further comprising one or more sources of electromagnetic radiation configured to selectively emit electromagnetic radiation with a first radiation characteristic or a second radiation characteristic, and electrical circuitry configured to selectively control the one or more sources of electromagnetic radiation to emit electromagnetic radiation having the first radiation characteristic in the first switch configuration and to emit electromagnetic radiation having the second radiation characteristic in the second switch configuration, wherein the second radiation characteristic is different from the first radiation characteristic, and wherein the first switch is pre-configured to assume the first switch configuration and adapted to switch from the first to the second switch configuration only for the duration that the first switch is operated or for a fixed time duration after the first switch was operated;
• an optical sensor capable of detecting different radiation characteristics of the tracker;
• and
• a processor configured to selectively identify the first or second switch configuration based on the radiation characteristic detected by the optical sensor.

A method for operating a tracker for a surgical navigation system, the tracker comprising a first switch configured to be operated between a first switch configuration and a second switch configuration, the first switch pre-configured to assume the first switch configuration and adapted to switch from the first to the second switch configuration only for the duration that the first switch is operated or for a fixed time duration after the first switch was operated, one or more sources of electromagnetic radiation, and electrical circuitry configured to selectively control the one or more sources of electromagnetic radiation to emit electromagnetic radiation with a first radiation characteristic or a second radiation characteristic, wherein the second radiation characteristic is different from the first radiation characteristic, wherein the method comprises:

• emitting, by the one or more sources of electromagnetic radiation, electromagnetic radiation having the first radiation characteristic in the first switch configuration;
• operating the switch so as to switch from the first switch configuration to the second switch configuration;
• and
• emitting, by the one or more sources of electromagnetic radiation, electromagnetic radiation having the second radiation characteristic in the second switch configuration.