Patents by Inventor Ramalinga R. Chirra

Ramalinga R. Chirra 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).

  • Wide aperture objective lens
    Patent number: 4368957
    Abstract: An objective lens comprising five lens elements and intended for use in an optical recording system wherein a laser beam is focused onto a recording surface located beneath a plastic layer over the disc. The disclosed lens has a relatively large numeric aperture of 0.75, but has a relatively large working distance between the lens and the disc and a relatively low total mass, to facilitate rapid movement of the lens. In addition, the lens is color corrected to accommodate a range of spectral frequencies present in the laser beam.
    Type: Grant
    Filed: October 31, 1980
    Date of Patent: January 18, 1983
    Assignee: Discovision Associates
    Inventor: Ramalinga R. Chirra