Patents by Inventor Lu-Jan Tan

Lu-Jan Tan 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).

  • Keyless electronic calculating pen
    Patent number: 4141073
    Abstract: Keyless Electronic Calculating Pen comprises a portable combination of a pen and an electronic calculator. Signals generated by the pen tip through designated strokes of numerals and calculating symbols upon writing on any surface of any writing medium are input directly to the calculator to perform calculating and displaying functions. The written record can be kept for checking and future reference.
    Type: Grant
    Filed: August 8, 1977
    Date of Patent: February 20, 1979
    Inventor: Lu-Jan Tan