optics: Quick Facts

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Last updated

Oct. 30, 2026

News •

Metalens microscope switches focus with voltage, not moving optics • Oct. 26, 2026, 5:20 PM ET (Phys.org)

Photos and Videos

Two diagrams compare light reflection: the top shows blue incident and reflected rays bouncing off a smooth surface, with equal angles from the normal; the bottom shows rays scattering from a rough surface, with normals and angles marked at various points.

$law of refraction$

$refractive indices and dispersive powers$

Close-up of fiber optic cables with glowing tips fanned out against a dark background, illustrating telecommunications technology.

Gauss theory of lenses

telescopic rifle sight

Are invisibility cloaks possible in reality?

Understand how a pinhole focuses light and why lenses are better than pinholes

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Topics

quantum optics catoptrics footcandle geometrical optics Lambert’s law optical system Standard Candle light lens formula Fermat’s principle atomic physics mechanics quantum mechanics Cosmology thermodynamics electronics acoustics biophysics cryogenics tribology

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Key People

Isaac Newton

Isaac Newton

English physicist and mathematician

Johannes Kepler

Johannes Kepler

German astronomer

Hermann von Helmholtz

Hermann von Helmholtz

German scientist and philosopher

Joseph Priestley

Joseph Priestley

English clergyman and scientist

Fermat, portrait by Roland Lefèvre; in the Narbonne City Museums, France

Pierre de Fermat

French mathematician

John William Strutt, 3rd Baron Rayleigh

Lord Rayleigh

British scientist

The discoverer of the principle of the aplanatic focus

Joseph Jackson Lister

British opticist

Fresnel, detail of an engraving by Ambroise Tardieu after a contemporary portrait, 1825

Augustin-Jean Fresnel

French physicist

Glauber, Roy J.

Roy J. Glauber

American physicist

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Sir David Brewster

Scottish physicist

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Raymond Neil Wilson

British physicist

Amici, Giovanni Battista

Giovanni Battista Amici

Italian astronomer

Peter Barlow

Peter Barlow

English optician and mathematician

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Giuseppe Campani

Italian inventor

Peiresc, Nicolas-Claude Fabri de

Nicolas-Claude Fabri de Peiresc

French humanist

Lippershey, Hans

Hans Lippershey

Dutch inventor

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Silvanus Phillips Thompson

British physicist and historian

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Frits Zernike

Dutch physicist

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John Dollond

British optician

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James Short

British optician and astronomer