Definition of collimate in English:



[with object]
  • 1Make (rays of light or particles) accurately parallel.

    ‘a collimated electron beam’
    • ‘The first and second lenses operate jointly to concentrate and collimate the incident light beam.’
    • ‘The excitation and transmitted light is collimated by a set of focusing lenses on either side of the sample chamber.’
    • ‘The scattered light is collimated, and simultaneously detected by a fixed array of 18 transimpedance photodiodes, which span an angular region from 22.5 [degrees] to 147 [degrees].’
    • ‘The TPIAL emits a highly collimated beam of infrared light for precision aiming, as well as a separate infrared illumination beam with adjustable focus.’
    • ‘Once you can gather up and collimate the light coming from an LED, you can use binary optical elements - holographic diffusers - to take that round, highly collimated beam and put it out into designer patterns.’
    1. 1.1 Accurately set the alignment of (an optical or other system)
      ‘manuals give detailed instructions for collimating the optics’
      • ‘The helicopter's weapon sighting system is the PKV collimating sight.’
      • ‘Our SBC cavity incorporates a single collimating lens located a focal length away from a 1 - D array of laser emitters operating at different wavelengths, with the grating positioned another focal length away on the other side of the lens.’
      • ‘I have done this many times while collimating a telescope's optical alignment and checking for the circular diffraction rings that occur at the same distance in and out of focus.’
      • ‘In comparison, in a collimated system the peak wavelength varies across the FOV of the etalon filter according to = / 2n.’
      • ‘The most common method for measuring retardance and fast-axis orientation involves placing two linear polarizers with horizontally aligned axes between a collimated optical source and a detector.’
      adjust, regulate, synchronize, coordinate, harmonize
      View synonyms


Mid 19th century: from Latin collimare, an erroneous reading (in some editions of Cicero) of collineare ‘align or aim’, from col- ‘together with’ + linea ‘line’.