A spatial filter enables a laser beam to be filtered such that noise around the beam is reduced. A beam with a spatial filter will appear "cleaner", with less imperfections. The spatial filter consists of a focusing lens and a pinhole placed at the focus point of that lens. The beam goes through the lens, gets focused at the pinhole, and the parts of the beam that have diverged from the focus point due to imperfections in the lens or contamination will not go through the pinhole. Optical noise around the beam is thus filtered out. Lasiris Spatial Filters
A filter that operates in the spatial domain as opposed to the frequency domain to accentuate or attenuates the appearance of the spatial details, for example the transitions of intensity in an image.
a device which improves the spatial coherence of a laser beam by effectively removing the background noise, i
An image transformation, usually a one-to-one operator used to lessen noise or enhance certain characteristics of the image. For any particular (x,y) co-ordinate on the transformed image, the spatial filter assigns a grey shade on the basis of the grey shades of a particular spatial pattern near the co-ordinates (x,y).
An assembly that is used in conjunction with laser applications to eliminate spatial noise. A pinhole is used to select only the central peak of the intensity pattern from a focused spot. The size of the pinhole is selected based upon the wavelength, objective focal length, and input beam diameter.
A spatial filter is an optical device which uses the principles of Fourier optics to alter the structure of a beam of coherent light or other electromagnetic radiation. Spatial filtering is commonly used to "clean up" the output of lasers, removing aberrations in the beam due to imperfect, dirty, or damaged optics, or due to variations in the laser gain medium itself. This can be used to produce a laser beam containing only a single transverse mode of the laser's optical resonator.