Q Factor - Optical Systems

Optical Systems

In optics, the Q factor of a resonant cavity is given by


Q = \frac{2\pi f_o\,\mathcal{E}}{P}, \,

where is the resonant frequency, is the stored energy in the cavity, and is the power dissipated. The optical Q is equal to the ratio of the resonant frequency to the bandwidth of the cavity resonance. The average lifetime of a resonant photon in the cavity is proportional to the cavity's Q. If the Q factor of a laser's cavity is abruptly changed from a low value to a high one, the laser will emit a pulse of light that is much more intense than the laser's normal continuous output. This technique is known as Q-switching.

Read more about this topic:  Q Factor

Famous quotes containing the words optical and/or systems:

    It is said that a carpenter building a summer hotel here ... declared that one very clear day he picked out a ship coming into Portland Harbor and could distinctly see that its cargo was West Indian rum. A county historian avers that it was probably an optical delusion, the result of looking so often through a glass in common use in those days.
    —For the State of New Hampshire, U.S. public relief program (1935-1943)

    We have done scant justice to the reasonableness of cannibalism. There are in fact so many and such excellent motives possible to it that mankind has never been able to fit all of them into one universal scheme, and has accordingly contrived various diverse and contradictory systems the better to display its virtues.
    Ruth Benedict (1887–1948)