Patents by Inventor Stephen A. Roen

Stephen A. Roen 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).

  • Solar powered portable calculator
    Patent number: 4017725
    Abstract: A portable calculator utilizing a solar panel array which can be either slidably moved within the calculator's housing or pivotly connected to it and which when exposed to incident light provide power for the calculator.
    Type: Grant
    Filed: January 3, 1975
    Date of Patent: April 12, 1977
    Assignee: Litton Business Systems, Inc.
    Inventor: Stephen A. Roen