Hi mohammed ridha al-shamapti,
As we know that CW Laser Generates a continuous wave (CW) optical signal.
The laser phase noise is modeled using the probability density function:
f(delta Phi) = 1/(2*pi*sqrt(delta f *dt)* exp.(- delta Phi^2/4*pidelta f *dt)
where delta Phi is the phase difference between two successive time instants and dt is the
time discretization. A Gaussian random variable for the phase difference between two
successive time instants with zero mean and a variance equal to 2*pi* sqrt(delta f) has been
assumed, with as the laser line-width (which is equivalent to the full width half
maximum (FWHM) of the laser power spectrum).
As The term “laser” is an acronym for (L)ight (A)mplification by
(S)timulated (E)mission of (R)adiation. To understand the laser, one
needs to understand the meaning of these terms. The term “light”
is generally accepted to be electromagnetic radiation ranging from
1 nm to 1000 mm in wavelength. The visible spectrum (what we see)
ranges from approximately 400 to 700 nm. The wavelength range
from 700 nm to 10 mm is considered the near infrared (NIR), and
anything beyond that is the far infrared (FIR). Conversely, 200 to
400 nm is called ultraviolet (UV); below 200 nm is the deep ultraviolet
(DUV).
Thanks,