diopter
noun
di·op·ter
dī-ˈäp-tər 
ˈdī-ˌäp-
: a unit of measurement of the refractive power of lenses equal to the reciprocal of the focal length in meters
Examples of diopter in a Sentence
Recent Examples on the Web
Old fashioned filmic techniques like split diopter shots, iris wipes, and chiaroscuro lighting add another layer of maximalist flare to the whole affair.
—
Marya E. Gates, IndieWire, 9 Sep. 2025
There’s also electrochromic film to darken the shades, and full customization with nose pieces, diopter dials, and adjustable temples with lighting effects.
—Julian Chokkattu, Wired News, 19 July 2025
The Sentinel XRs also allow users to adjust brightness across 10 levels to adapt to different game content and individual sight tolerances, as well as supporting a universal fit design and adjustable diopter settings that work across a 0 to -5.0D range.
—John Archer, Forbes.com, 30 June 2025
Our tester found the twist-out eyecups and diopter worked well, but the objective lens caps were a tight fit.
—Scott Gilbertson, WIRED, 6 Oct. 2024
Current Clinical Trials and Outcomes Clinical trials have started on the effectiveness of spiral diopter lenses for correcting presbyopia.
—William A. Haseltine, Forbes, 26 Feb. 2024
While keeping the left side covered, rotate the diopter dial on the right eyecup until the image is in focus.
—Katherine Alex Beaven, Travel + Leisure, 17 Jan. 2024
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Marya E. Gates, IndieWire, 9 Sep. 2025
There’s also electrochromic film to darken the shades, and full customization with nose pieces, diopter dials, and adjustable temples with lighting effects.
—Julian Chokkattu, Wired News, 19 July 2025
The Sentinel XRs also allow users to adjust brightness across 10 levels to adapt to different game content and individual sight tolerances, as well as supporting a universal fit design and adjustable diopter settings that work across a 0 to -5.0D range.
—John Archer, Forbes.com, 30 June 2025
Our tester found the twist-out eyecups and diopter worked well, but the objective lens caps were a tight fit.
—Scott Gilbertson, WIRED, 6 Oct. 2024
Current Clinical Trials and Outcomes Clinical trials have started on the effectiveness of spiral diopter lenses for correcting presbyopia.
—William A. Haseltine, Forbes, 26 Feb. 2024
While keeping the left side covered, rotate the diopter dial on the right eyecup until the image is in focus.
—Katherine Alex Beaven, Travel + Leisure, 17 Jan. 2024
Cite this Entry
“Diopter.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diopter. Accessed 31 Oct. 2025.
Copy CitationMedical Definition
diopter
noun
di·op·ter
variants
or chiefly British dioptre
: a unit of measurement of the refractive power of a lens equal to the reciprocal of the focal length in meters
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