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NDI Optical Measurement Technology

Optical Tracking Video Image

The goal of optical measurement is to calculate the location and orientation of an object or tool within a defined coordinate system. Optical tracking uses a position sensor to detect infrared-emitting or retro-reflective markers affixed to a tool or object. The position sensor calculates the position and orientation of the tool based on the information the position sensor receives from those markers.

There are two types of markers that can be used in optical tracking, including:

NDI's Polaris Spectra and Polaris Vicra use optical measurement and are integrated into medical solutions that have been widely adopted for use in computer-assisted therapy applications ranging from implant placement to radiation therapy to ergonomic studies to neurosurgery.

Advantages of NDI Optical Tracking

Advantages offered by NDI's Polaris Family of optical tracking products, include:

  • Large working volume
  • Very small, portable solutions
  • Ability to track either or both active and passive markers
  • High degree of measurement accuracy (up to 0.3mm RMS↑)
  • Measures accurately within a large operating temperature range
  • Ability to perform quick in-field accuracy assessment

NDI Optical Products

NDI's optical measurement products include the Polaris Spectra and the Polaris Vicra.

For further details on how NDI incorporates optical measurement technology into their systems, see How the Polaris Works.

See related article in October 2007 issue of NDI InFocus
InFocus Medical Newsletter




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