Optical tracking device with optically distinguishable lines

A surgical navigation system comprising:

• an optical tracking device comprising:
• a body having at least two optically distinguishable lines, wherein the lines have a fixed spatial relationship between each other, and each of the lines is an edge of the body, and at least one light emitter disposed in the body and configured to illuminate a first of the lines and a surface area of the body having a second of the lines as boundary, wherein the first and second lines do not lie in a single plane,
• wherein the at least one light emitter is configured to illuminate the first line to exhibit a first light emitting behavior and illuminate the surface area to exhibit a second light emitting behavior, the first light emitting behavior differing from the second light emitting behavior in temporal pattern of emitted light such that a first temporal light pattern of the first light emitting behavior is anticyclic to a second temporal light pattern of the second light emitting behavior;
• an optical detection system configured to detect the lines of the optical tracking device from the illumination of the first line and the surface area, wherein the lines of the optical tracking device are configured to be detected by the optical detection system simultaneously;
• and
• one or more processors configured to determine a spatial position and/or orientation of the optical tracking device based on the detected lines and based on the fixed spatial relationship between the at least two optically distinguishable lines.

A surgical navigation method of determining a spatial position and/or orientation of an optical tracking device, comprising:

• providing an optical tracking device comprising a body and at least one light emitter disposed in the body, the body having at least two optically distinguishable lines, wherein each of the lines is an edge of the body, the lines do not lie in a single plane, and the at least one light emitter is configured to illuminate a first of the lines to exhibit a first light emitting behavior and illuminate a surface area of the body to exhibit a second light emitting behavior, the surface area having a second of the lines as boundary, and the first light emitting behavior differing from the second light emitting behavior in temporal pattern of emitted light such that a first temporal light pattern of the first light emitting behavior is a nticyclic to a second temporal light pattern of the second light emitting behavior;
• acquiring data describing a fixed spatial relationship between the lines;
• simultaneously detecting the lines from the illumination of the surface area and the first line;
• and
• determining, based on the detected lines and based on the fixed spatial relationship, the spatial position and/or orientation of the optical tracking device.