Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
FWHM=full width half maximum ,,,as far as i could remember in the relation of power(intensity) vs wavelength (frequency) u get the difrence between the two values of wavelength(freq.) at which the power(intensity) is equal to half the maximum value ,actually i am not really sure so try to check it again.
In the optical community it is always something of a debate at to what you define as a pulse width. While many people subscribe to the Full width of the pulse at half of the maximum peak others will define their applications puls width as measured at the (1/e) points. My self I have always been in the FWHM camp. However I can see where others would want to drop the measurement down to where the signal is still very present at the 1/e points. This does have the effect of making the pulse width larger than it would be measured at FWHM. If the pulse is gausian in nature this can be a big difference. If the pulse is more of a "top hat" or square pulse this will be of little difference in pulse width. Like most things it depends on your application.