Definition of lens in US English:



  • 1A piece of glass or other transparent substance with curved sides for concentrating or dispersing light rays, used singly (as in a magnifying glass) or with other lenses (as in a telescope).

    • ‘If you wear glasses have your reading lens fitted to your polarized ones.’
    • ‘Light flashed across the round lenses of his glasses.’
    • ‘Because of the extreme curve of the glasses, the lenses are hard to fit to a frame - and that makes them costly.’
    • ‘His novel idea was to use both mirrors and lenses in his telescope.’
    • ‘Each cluster acts as a magnifying lens, greatly brightening a quasar's light.’
    • ‘In 1935, Zeiss found a coating of magnesium fluoride on glass lenses dramatically improved image quality.’
    • ‘Isaac Newton proposed using a curved mirror, rather than a lens, to magnify the heavens, and reflecting telescopes are nowadays the norm.’
    • ‘An air bubble in water that is shaped like a normal glass lens would have roughly the opposite effect of the glass lens.’
    • ‘He was particularly interested in the ideas of improving telescope design by using lenses made up of two different types of glass.’
    • ‘Most conventional lenses are made of glass, polymer, or other transparent solid materials.’
    • ‘Galileo's telescope had a convex object lens but a concave eye-piece.’
    • ‘Some of the other options include glass lenses and plastic lenses.’
    • ‘But what appeared to be a minute particle of dirt on a telescope lens was in fact a rare daylight view of the planet Mercury crossing in front of the Sun.’
    • ‘I have two pairs of glasses with different coloured lenses for different light conditions.’
    • ‘Galileo's telescope was similar to a pair of opera glasses in that it used an arrangement of glass lenses to magnify objects.’
    • ‘These foreground clusters act as lenses that magnify the light of the protogalaxies and allow us to detect and study them.’
    • ‘It could have been a bit of dirt on the lens of the telescope but it was really clear through the viewer.’
    • ‘His first telescope was made from available lenses and gave a magnification of about four times.’
    • ‘Using his experimental abilities, he ground lenses and assembled a telescope.’
    • ‘The lens that picks up the light from the focal point is called the eyepiece lens.’
    1. 1.1 The light-gathering device of a camera, typically containing a group of compound lenses.
      • ‘Being able to move the camera lens for focusing and zooming would allow picture phones to take clear telephoto shots and focus on objects close-up.’
      • ‘Camera lenses, no matter how expensive, are nowhere near as acutely sensitive as the human eye, nor does the camera see colour in exactly the same way.’
      • ‘Stuff like this makes me want to get a fish-eye lens for my digital camera.’
      • ‘The Standard lens is actually one of the most neglected lenses in your camera bag.’
      • ‘Photography is now about computers as much as it is about cameras and lenses.’
      • ‘The solution to this is to get right next to the glass, so that your camera lens is flush with the glass surface.’
      • ‘We were looking through our camera lenses, and we could see them waving to us and they kept shooting at us.’
      • ‘Controlled by software, tiny motors on the lens assembly and spherical camera casing allow the lens to pan and track objects.’
      • ‘They proceeded to display cases located at the store's front and stole 18 digital and film cameras along with eight camera lenses.’
      • ‘If your subject is nearby, you can often isolate details with a normal lens or moderate telephoto.’
      • ‘Some of these were made not simply without lenses but without a camera at all - rather by the direct manipulation of photographic plates.’
      • ‘Zooming the camera lens even further, she saw figures off to the right, walking in front of one of the gray tents.’
      • ‘If possible, bring a camera with interchangeable lenses.’
      • ‘Of course the best cameras and lenses can produce images of superior technical quality to gear that is less capable.’
      • ‘All mating trials were video-recorded by using cameras with macrozoom lenses to allow detailed analysis of the mating sequence.’
      • ‘With that he tosses the paper across, and goes back to his camera lenses and his camera lens cloth.’
      • ‘The lens of the eye works much like the lens of a camera.’
      • ‘Store cameras and lenses in padded cases and, in very damp environments, in locking plastic bags or even underwater housings.’
      • ‘But once the officers checked out the tape over the camera lenses, they decided to rewind and review the videos anyway.’
      • ‘Scott also plays with lenses, camera speed and some excellent special effects to heighten the impact of the harrowing fight scenes.’
    2. 1.2Anatomy
      • ‘The vitreous humor is between the back of the lens and the retina.’
      • ‘The eye fluid nourishes the bloodless lens and cornea.’
      • ‘With age, your eyes are less able to produce tears, your retinas thin and your lenses gradually turn yellow and become less clear.’
      • ‘The posterior chamber is found behind the iris and in front of the lens and ciliary bodies.’
      • ‘The dioptric system includes the cornea, the lens, the aqueous humor within the anterior eye chamber, and the vitreous body.’
    3. 1.3
      short for contact lens
    4. 1.4Physics An object or device which focuses or otherwise modifies the direction of movement of light, sound, electrons, etc.
      • ‘The first and second lenses operate jointly to concentrate and collimate the incident light beam.’
      • ‘In order to concentrate more light at the aperture, they placed a glass ball lens on the upper side of the tip prior to the assembly step.’
      • ‘Negative refraction implies that a converging lens made from negative-index material should have a concave surface rather than a convex one.’
      • ‘Polycarbonate is a tough, transparent thermoplastic that's used to make thin, light lenses.’
      • ‘Designed much like a compound microscope, the electron microscope uses a beam of electrons focused through magnetic lenses.’


Late 17th century: from Latin, ‘lentil’ (because of the similarity in shape).