Acronyms

Instrument Control Frame

The 3 axis, orthogonal, system that defines the instrument coordinate system. This coordinate system is described in more detail in package skretrieval. The \(\hat{x}_{ICF}\) unit vector is assumed to point along the primary optical axis, or boresight, away from the instrument. The \(\hat{y}_{ICF}\) and \(\hat{z}_{ICF}\) unit vectors normally lie in the plane of the detector and the choice of orientation is arbitrary although we recommend that the \(\hat{z}_{ICF}\) axis be parallel to a sensible definition of “up” and \(\hat{y}_{ICF}\) lies in the horizontal direction.

The instrument will define look vectors in the instrument control frame and can then be mounted on a Platform described by class skretrievals.platforms.Platform. The Platform can be positioned and orientated in space and provides the appropriate set of transformations to convert look/unit vectors defined in the instrument control frame to look/unit vectors in the ECEF geocentric control frames.