Definition of optical axis in US English:

optical axis


  • 1A line passing through the center of curvature of a lens or spherical mirror and parallel to the axis of symmetry.

    • ‘That could lead to lenses with parallel sides and no optical axis able to focus a point image.’
    • ‘A lamp rotates around the optical axis in a plane between the camera and the object.’
    • ‘It is expressed in terms of the angle subtended between the outer rays of the beam and the optical axis, as shown in Figure 3.’
    • ‘The main problem with their lens was keeping it centered around the optical axis.’
    • ‘Finally, it allows spatial resolution in the plane perpendicular to the optical axis.’
    1. 1.1Crystallography A direction in a doubly refracting crystal along which a light ray does not undergo double refraction.
      • ‘Each region has an optical axis specified by the direction and depth of orientation of liquid crystal molecules along the surface of the liquid crystal film structure.’
      • ‘Optically, the test appears to be constructed of randomly oriented grains, but in fact the crystals are highly ordered so that their optical axes are uniformly oblique to the surface of the test.’
      • ‘This type of device is to be configured in such a way that it can be used for detecting material with optical axes in various directions without requiring assembly.’