The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 29, 1994
Filed:
Feb. 14, 1992
Bruce H Ostermeier, Irvine, CA (US);
CalComp Inc., Anaheim, CA (US);
Abstract
An ink sensing system for a vector plotter in which a pen is adapted to be raised and lowered from a drawing media surface along a system axis. An optical detection system is provided which has a focal point on the system axis and below the media surface when the pen is in its lowered position and at the media surface when the pen is in its raised position. The optical detection system includes a source of illumination and a detector system to determine the degree of reflectance from the media surface to indicate the presence or absence of ink on the media surface. In a particular embodiment the optical detection system is moveable and the movement of the optical detection system is coupled to the movement of the pen. Furthermore, the focal point of the optical detection system coincides substantially with the last point of contact of the pen with the media surface when the pen is in the raised position.