Airy disk


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Airy disk: light distribution in Airy disk image of single point source (left) and two just resolvable point sources

Airy disk

(air -ee) The bright disklike image of a point source of light, such as a star, as seen in an optical system with a circular aperture. The disk is formed by diffraction effects in the instrument and is surrounded by faint diffraction rings that are only seen under perfect conditions (see illustration). The disk diameter, first calculated by George Airy in 1834, is the factor limiting the angular resolution of the telescope.

Airy disk

[¦er·ē ¦disk]
(optics)
The bright, diffuse central spot of light formed by an optical system imaging a point source of light.
References in periodicals archive ?
It is actually a small disk, known as the Airy disk, surrounded by a series of diffraction rings, with the first ring being prominent and the rest dim.
At the focus the image of a star appears as a small bright disk surrounded by concentric rings of diminishing brightness, known as Airy disk or diffraction spot.
As a result, constructive and destructive interference occurs, forming a so-called Airy disk instead of an infinitely small focused point.
This pattern is called the Airy disk after George B.
Doesn't an obstruction make the center of the Airy disk slightly smaller?
A scope with a central obstruction shows a slightly larger Airy disk (the bright center of a star's diffraction pattern) than an unobstructed aperture.
The smallest focused spot is called the Airy disk, which depends on the wavelength of light and the aperture of the optical system.
After slight tweaks to the telescope's collimation, the optics yielded classic Airy disk diffraction patterns around stars at high powers, and double stars such as Epsilon Lyrae were well resolved.
The result is an Airy disk that is 16 times brighter.
Viewed at high power, stars looked "textbook perfect," with little evidence of spherical aberration disturbing their Airy disk patterns, and there was no hint of astigmatism distorting them into ellipses or other odd shapes from malformed or pinched optics.
The size of the Airy disk is determined by the telescope's aperture and the light's wavelength.
And at these magnifications, stars appeared as textbook-perfect Airy disks surrounded by a bull's-eye pattern of uniformly illuminated diffraction rings, which decreased in brightness outward from the Airy disk.