Real time particle fallout monitor with tubular structure

DETAILED DESCRIPTION OF THE INVENTION FIG.
1 depicts a configuration of an optical system that is employed with a particle flux monitor, in accordance with this invention.
A light source 10, such as a laser, provides a light beam 12 to a mirror 14 which reflects the beam to a second mirror 16.
The light beam is reflected several times between the mirrors to form a light net 2.
The beam is finally reflected to a beam stop 18.
Light that is scattered by particles that appear within the light net is sensed by a pair of photosensors 22 (see FIG.
2) which are electrically connected and the signal generated by the photosensors is amplified in an amplifier 24 and applied to a data processor 26.
As shown in FIG.
2, a particle flux monitor 1 which includes the elements of the optical configuration of FIG.
1 is enclosed by a housing or enclosure 20 wherein the light net 2 is generated.
Light detectors or photosensors 22 are positioned adjacent to the light net to receive light scattered by any particle 4 that passes within the light net.
The photosensors 22 generate a signal in response to the scattered light and the generated signal is amplified and processed by the data processor or computer 26.
The processor collects and analyzes the data and thereby provides a warning if the magnitude of particle fallout is greater than a specified level.
In accordance with this invention, a tubular structure 3, which is open at the top and bottom, is seated or attached to the housing 20 of the particle flux monitor 1.
The tubular structure surrounds an opening 28 formed on the surface of the housing 20.
The lateral air flow pattern in the interior of the tubular structure is indicated by the arrows or stream lines 5.
It is known that an air flow passing an opening will create a turbulent flow that occurs near the top of the opening of the tubular structure, in accordance with the principles of aerodynamics.
The air flow at the bottom of the tubular structure which is seated on the enclosure 20 will be relatively still and virtually static