Patents by Inventor H. Allen Zimmerman

H. Allen Zimmerman has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Optical detection of water droplets using light refraction with a mask to prevent detection of unrefracted light
    Patent number: 5386111
    Abstract: An optical detection system for detecting rain or other water droplets on the outer surface of a window and fog on the inner surface with a single photo-detector. The invention measures the accumulation of water droplets on the window by light refraction of a first light beam with droplets to redirect a first light beam to the photo-detector. A masking device prevents light from reaching the photo-detector directly without refraction. As a result the rain measurement output signal of the photo-detector increases with an increasing accumulation of water droplets on the window. The fog accumulation is measured by a second light beam reflected off the inner surface of the window to the photo-detector so that the output signal of the photo-detector decreases with increasing amounts of fog since fog scatters the light to reduce the amount of light reflected to the photo-detector.
    Type: Grant
    Filed: October 8, 1993
    Date of Patent: January 31, 1995
    Inventor: H. Allen Zimmerman
  • Optical detection of water droplets using light refraction with a mask to prevent detection of unrefracted light
    Patent number: RE35762
    Abstract: An optical detection system for detecting rain or other water droplets on the outer surface of a window and fog on the inner surface with a single photo-detector. The invention measures the accumulation of water droplets on the window by light refraction of a first light beam with droplets to redirect a first light beam to the photo-detector. A masking device prevents light from reaching the photo-detector directly without refraction. As a result the rain measurement output signal of the photo-detector increases with an increasing accumulation of water droplets on the window. The fog accumulation is measured by a second light beam reflected off the inner surface of the window to the photo-detector so that the output signal of the photo-detector decreases with increasing amounts of fog since fog scatters the light to reduce the amount of light reflected to the photo-detector.
    Type: Grant
    Filed: November 13, 1995
    Date of Patent: April 7, 1998
    Inventor: H. Allen Zimmerman