18 Questions 230 Answers 0 Followers
Questions related from Parviz Parvin
Red planet: blue sunset Blue planet: red sunset Rayleigh scattering, Mie scattering or other effects, which one is dominant effect?
03 April 2016 7,238 7 View
A chirped pulse is a pulse in which the wavelength changes during the duration of the pulse.The output of a laser may be chirped intentionally to create a high-powered, extremely short pulse. In...
10 January 2016 9,435 5 View
There are two major techniques to measure ps - fs pulses of the mode-locked lasers: I) Steak camera II) Optical autocorrelation According to the space-time transformation in second-order...
02 January 2016 7,537 3 View
A nanomotor is a molecular or nanoscale device capable of converting energy into movement. It can typically generate forces on the order of pico-Newtons. The applications consists of directed...
12 March 2015 2,485 3 View
Laser with stable resonator creates the axial and traverse modes. The mode frequency is a function of mirror radii and the resonator length as well as the effect of transverse modes. What about...
06 March 2015 9,194 4 View
Amplified spontaneous emission (ASE) is so strong in high gain lasers (dye, excimer, FEL, etc.) that may be mistaken with the coherent light. How can we distinguish and suppress ASE?
06 March 2015 6,103 15 View
I know Michelson Interferometry for the temporal and coherence length measurements and Shack-Hartmann wave front sensor for the spatial coherence detection. What else do you suggest?
17 February 2015 5,623 9 View
The linearly polarized light incident to the tissue gives us different response from the surface and the bulk in the highly scattering tissues such as dermis, retina, etc. The reflected light...
24 January 2015 5,677 3 View
To my knowledge, there is no solid correlation between temporal or spatial coherence and the polarization of light (linear, circular or elliptical) because the coherence arises from the nature of...
05 January 2015 4,107 12 View
There are a number of models to analyze propagation of light in scattering media, including ballistic, diffusion, Kublai-munk, Monte-Carlo etc. The multiple scattering resembles to be dominant in...
05 January 2015 7,979 3 View
The de-polariztion lidar functions based on linear polarization of laser. An electro -optical Q-Sw Nd:YAG laser is usually used. The depolarization ratio is measured by the detection of...
17 September 2014 3,067 9 View
The planar phase front and the spherical phase front may change the focal point of an ideal micro-lens ( having min aberration). This fact may be enhanced drastically for an incident distorted...
18 February 2014 710 46 View
Being transparent or creating an illusion? I may propose a device to transfer the images from one location to display at another location using the optical fibers. Furthermore, invisibility may be...
11 February 2014 3,031 97 View
Graphene is a nano structure. It is a 2-D carbon sheet with a honeycomb structure that exhibits extraordinary physical and electrical properties. One outstanding electrical property of graphene is...
16 December 2013 5,022 5 View
Does it mean that light is particle? To my knowledge , the light detectors within any spectral range detects light based on photon property of light. The array detector function is also based on...
28 November 2013 2,347 33 View
Cancer consists of a series of diseases based on undesired cell proliferation. The cancerous cells are continuously formed in infectious organs whereas the human immunity system regularly...
16 November 2013 2,298 82 View
Dispersive materials somewhat slow down the light. Regarding the group velocity dispersion, the group velocity is smaller than phase velocity. The group velocity resembles to be much smaller in...
12 November 2013 1,577 28 View
Despite the set of rate equations formulate the instantaneous population of the upper and lower levels, the population inversion of laser transition, gain and saturation properties, however those...
09 November 2013 4,425 6 View
