Definition of optical in English:



  • 1Relating to sight, especially in relation to the action of light.

    ‘optical illusions’
    • ‘Radio astronomy is a young field relative to optical astronomy.’
    • ‘Hooper declared at the outset of his book that optical toys could hone visual perception and, consequently, prime social vigilance.’
    • ‘The new system should help remove the optical trickery that occurs when assistant referees fail to position themselves correctly on the sidelines.’
    • ‘Strobes and pyrotechnics nestle amongst shadow puppetry, while a vast array of other optical and audio effects assist in the delivery of this fast-moving tale.’
    • ‘Not only did Leonardo study the geometry of perspective but he also studied the optical principles of the eye in his attempts to create reality as seen by the eye.’
    • ‘The same optical illusion is in the second act.’
    optical, seeing, optic, ocular, eye
    1. 1.1Constructed to assist sight.
      ‘an optical aid’
      • ‘For some, the use of optical aids compromises genius, and art with it.’
      • ‘Counting how many Pleiads you can see without optical aid is a good test of both your vision and observing conditions; most people see 6 or 7.’
      • ‘Normally, when Christine and I do any serious bird watching, it is with the Core Team and their plethora of optical aids and identification tomes.’
      • ‘You may be able to watch Jupiter disappear - an event known as immersion - without optical aid, though binoculars help.’
      • ‘Concerning the question of optical aids, there is a possible answer well short of the use of lenses, mirrors, or a pinhole camera obscura.’
      • ‘This mismatch, he says, militates against the Hockney-Falco claim that the painter relied on optical aids.’
      • ‘Despite the efforts of some art historians to suggest that Vermeer literally transcribed what he saw with optical aids, such was not the case.’
      • ‘In addition, in bioengineering the low-power demands of this technology are promising for use in hearing aids and optical prosthetics.’
      • ‘The controversy over the use of optical aids by early Renaissance painters is crossdisciplinary and emotionally charged.’
      • ‘The optical sight works either by using ambient light or under low light conditions, from a battery or tritium insert.’
    2. 1.2Relating to the science of optics.
      • ‘Abbe described the optical process so well that this paper has become the foundation upon which much of our understanding of optical science rests today.’
      • ‘The list even includes a professor of optical sciences, Charles Falco.’
      • ‘Astronomy is one of the oldest and truest champions of optical science.’
      • ‘For 154 years, Zeiss has been an optical pioneer.’
      • ‘Strong cleaning agents like diluting agents or concentrated cleaners should be avoided since they may affect the optical properties of the sunglasses.’
      • ‘For instance, he shows how pencils can be used to explain optical principles.’
      • ‘Deception by mirrors has a basis in optical principles, in so far as reflections in mirrors do not correspond wholly to the objects that caused them.’
      • ‘Without doubt, uncovering nature's optical secrets has been, and will continue to be, a spectacular journey.’
  • 2Physics
    Operating in or employing the visible part of the electromagnetic spectrum.

    ‘optical telescopes’
    • ‘Of course, the capabilities of optical and infrared telescopes also continued to improve.’
    • ‘The paper shows that positrons can see defects better than either optical or electron beam microscopes.’
    • ‘Whether the telescope is operating as an optical or an infrared instrument, rarely will there be an astronomer peering through an eyepiece at the Keck's images.’
    • ‘An optical light microscope or a scanning electron microscope can be used to see these ‘invisible’ cracks.’
    • ‘In medium- and high-grade metamorphic terrains, these studies can be adequately accomplished with the aid of optical microscopy.’
    1. 2.1Electronics (of a device) requiring electromagnetic radiation for its operation.
      ‘integrated optical circuits’
      • ‘Here's a look at how test sequencers can speed up tests on optical devices, saving time and money.’
      • ‘Available optical devices such as CDs and DVDs record information on the surface of the disc.’
      • ‘Such a device might one day become the CPU of an optical computer.’
      • ‘Unlike its electrical predecessor, an optical switch does not convert the signal to an electrical impulse before directing it.’
      • ‘But you can easily add another hard drive, drop in a graphics card or add a new optical drive.’


Indian opticals
  • A pair of glasses.

    ‘he pushed his opticals on to the bridge of his nose’