Patents by Inventor Daniel B. Crabtree

Daniel B. Crabtree 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).

  • Lighting apparatus
    Patent number: 4336576
    Abstract: Lighting apparatus having less than the conventional number of light sources, but which provides illumination substantially equivalent to the illumination provided by the conventional apparatus, thereby providing savings in energy consumption and in cost of operation. Part of the light output of the light sources which are provided is reflected to illuminate areas of the diffuser plate which are illuminated by additional light sources in conventional apparatus, whereby it appears that a full number of light sources are provided when in fact less than a full number of light sources are provided.
    Type: Grant
    Filed: April 7, 1980
    Date of Patent: June 22, 1982
    Inventor: Daniel B. Crabtree