Complex Beam Parameter

In optics, the complex beam parameter is a complex number that specifies the properties of a Gaussian beam at a particular point z along the axis of the beam. It is usually denoted by q. It can be calculated from the beam's vacuum wavelength λ0, the radius of curvature R of the phase front, the index of refraction n (n=1 for air), and the beam radius w (defined at 1/e2 intensity), according to:

.

Alternatively, q can be calculated according to

where z is the location at which q is calculated, relative to the location of the beam waist, z0 is the Rayleigh range, and i is the imaginary unit.

Read more about Complex Beam Parameter:  Uses of The Complex Beam Parameter

Famous quotes containing the words complex and/or beam:

    The human mind is so complex and things are so tangled up with each other that, to explain a blade of straw, one would have to take to pieces an entire universe.... A definition is a sack of flour compressed into a thimble.
    Rémy De Gourmont (1858–1915)

    Why beholdest thou the mote that is in thy brother’s eye, but considerest not the beam that is in thine own eye?
    Bible: New Testament Jesus, in Matthew, 7:3.

    From the Sermon on the Mount.