Talk:Ultrashort pulse

Medical imaging applications
Regarding applications: What are the applications of ultrashort (laser) pulses in medical imaging? I cannot think of any. The referenced article does not provide any information about it either.Gabeng 06:51, 6 Jun 2005 (UTC)


 * Imaging isn't really my subfield, but I do know of some biological imaging applications, especially with in vivo tomography. An example I know of is the OCM, which just switched from a CW to a pulsed lightsource. This article (Seeing through tissue section) discusses imaging tumors in addition to the surgical applications.


 * I think more information could be had from the Virtual Journal of Ultrafast Science, which is subscription, or from Google Scholar .--Laura Scudder | Talk 18:24, 5 Jun 2005 (UTC)

Dec 15 2010 : I think the applications of fs pulses in Optical tomography of biological/human tissues are appearing for quite some time. This field is quite active and at our institute also people are working on this area (www.rrcat.gov.in).The generation of super continuum can also be metioned here. regards -prasad —Preceding unsigned comment added by 144.16.111.210 (talk) 07:10, 15 December 2010 (UTC)

Proposed merge of ultrafast and ultrashort pulse
I propose that Ultrafast should be merged here. per Naming conventions (adjectives), adjectives should redirect to nouns. This article seems like the appropriate place for ultrafast to redirect to.--Srleffler 05:53, 11 November 2006 (UTC)

Propagation of light pulses
I propose to add some material concerning the propagation of light pulses in various media, some analytical and therefore reasonably general. —Preceding unsigned comment added by 98.234.179.52 (talk) 00:51, 23 August 2009 (UTC)

Pulse plot


It seems like this image has some problems. First, the blue curve (not the green curve) is the electric field amplitude; the green curve is the envelope of the pulse. Second, the red curve is (I presume) supposed to show the time-averaged intensity of the pulse, in which case (a) it should say that, and (b) the peak intensity should reach half of the peak amplitude because of the factor of 1/2 from the sinusoid. Anyway, I made a new SVG image and unless someone objects I'll substitute it into the article in a few days. Zueignung (talk) 19:46, 20 October 2012 (UTC)

This may be purely an issue of language, but I think there is somehing wrong with this plot, or at least its use. It is described correctly as an ultrashort pulse which has a quadratic phase dependence which also means it is chirped. But the way this is currently used in the article the impression is given that ALL ultrashort pulses are chirped. This is absolutely not the case, and ultrashort pulses are usually unchirped in order to obtain the narrowest possible pulse in time. I think this should be made more clear. It might be best to provide a plot of an unchirped ultrashort pulse and a chirped ultrashort pulse. Using pulses with the same bandwidth (and therefore different temporal width for chirped and unchirped pulses) would offer more opportunity to make this concept clear. 157.185.95.42 (talk) 15:59, 1 July 2013 (UTC)mjd

To elaborate a little on the chirp: It is true that most high-power pulse amplifiers are chirped internally, but the output pulse in always unchirped to narrow it in time (ultra-short). The pulse depicted here would be about 10 times shorter in time if it were unchirped. So it should be. If we're only going to show one pulse, it should be unchirped, since that is more ultrashort than the chirped internal pulse shown here. 199.46.200.231 (talk) 00:46, 2 April 2014 (UTC)

Applications
'''I would like to add the following text to this section. Unfortunately, it involves a kind of self-referencing. Can anyone help?'''

Unfortunately, there are many claims in the literature on the applications of short laser pulses while few, if any, of these  claims live up to markets’ expectations and soon sink into oblivion. Therefore, it is believed that the relevant applications are much fewer than the large list one can compile by gathering those  suggested by the researchers in universities. An interesting anecdote may clarify the situation. "Someone approached us for advice on a flat transparent thin sheet of inert polymer having mono-dispersed pores for application in health  science to remove bacteria from biological fluids. The pores were desired to have diameters of  0.4 μm with a pore density of about 108 pores per cm2. Obviously, such pores cannot be drilled using commercially available high repetition rate lasers since the pore diameter is smaller than their wavelength. However, recalling the published work on drilling to sub-wavelength diameters we suggested using the high repetition 100 fs Ti:Sapphire laser pulses as a suitable and feasible method. To our dismay, few days later, we learnt of commercially available polycarbonate membrane filters with well characterized characteristics having list prices as low as 0.2 $/cm2" ! Sharifi and Talebpour have identified three areas that short pulses may provide relevant applications. These include highly specific mass spectroscopy of molecules, continuum-less laser induced breakdown spectroscopy, and flat panel display dicing. Other potential applications are listed in the following: — Preceding unsigned comment added by Abdossamad Talebpour (talk • contribs) 00:59, 3 September 2013 (UTC)
 * Try a more impartial tone. Fgnievinski (talk) 01:08, 8 July 2014 (UTC)