Comparison To Gaussian Beam Focus
A circular laser beam with uniform intensity profile, focused by a lens, will form an Airy pattern at the focal plane of the lens. The intensity at the center of the focus will be where is the total power of the beam, is the area of the beam ( is the beam diameter), is the wavelength, and is the focal length of the lens.
A Gaussian beam with diameter of D focused through an aperture of diameter D will have a focal profile that is nearly Gaussian, and the intensity at the center of the focus will be 0.924 times .
Read more about this topic: Airy Disk
Famous quotes containing the words comparison, beam and/or focus:
“But the best read naturalist who lends an entire and devout attention to truth, will see that there remains much to learn of his relation to the world, and that it is not to be learned by any addition or subtraction or other comparison of known quantities, but is arrived at by untaught sallies of the spirit, by a continual self-recovery, and by entire humility.”
—Ralph Waldo Emerson (18031882)
“How can one beam alone support a house?”
—Chinese proverb.
“Carlyle is not a seer, but a brave looker-on and reviewer; not the most free and catholic observer of men and events, for they are likely to find him preoccupied, but unexpectedly free and catholic when they fall within the focus of his lens.”
—Henry David Thoreau (18171862)