Showing posts with label patents. Show all posts
Showing posts with label patents. Show all posts

How to produce stationary wave fields


A cylindrical surface of stationary light from
Zamboni-Rached, M., Recami, E., & Hernández-Figueroa, H. (2005). Theory of "frozen waves": modeling the shape of stationary wave fields Journal of the Optical Society of America A, 22 (11) DOI: 10.1364/JOSAA.22.002465 (arXiv)
On the 15th december, 2005, was published an interesting patent (I found it via Research Gate), Method and apparatus for producing stationary intense wave fields of arbitrary shape by Erasmo Recami, Michel Rached Zamboni, Hugo Enrique Ernandez Figueros, Valerio Abate, Cesar Augusto Dartora, Kleber Suza Nobrega, Marco Mattiuzzi:
Method for producing a stationary wave field of arbitrary shape comprising the steps of defining at least one volume being limited in the direction of the axis of propagation of a beam, of the type $0 \leq z \leq L$; defining an intensity pattern within the said region $0 \leq z \leq L$ by a function $F(z)$, describing the said localized and stationary intensity pattern, which is approximated by means of a Fourier expansion or by a similar expansion in terms of (trigonometric) orthogonal functions; providing a generic superposition of Bessel or other beams highly transversally confined; calculating the maximum number of superimposed Bessel beams the amplitudes, the phase velocities and the relative phases of each Bessel beam of the superposition, and the transverse and longitudinal wavenumbers of each Bessel beam of the superposition.
The invention is based on the following theoretical papers:

A grave alarm

posted by @ulaulaman about an invention by #AugustLindquist
My invention relates to improvements in grave alarms, whereby persons who are prematurely buried before life is extinct, can sound an alarm, thus notifying the cemetery officials of the fact.
The object of my invention, is not only to provide means for sounding an alarm, but also to provide an improved construction whereby fresh air is supplied to the person prematurely buried, whereby life may be sustained until help arrives.
from the patent by August Lindquist
Read also: Grave Alarm, 10 medical and scientific discovery in weird history
via greatgrottu