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:
Jun. 16, 1992
Filed:
Mar. 08, 1991
Anthony E Zank, Simi Valley, CA (US);
Michael N Gilano, Irvine, CA (US);
Kenneth S Gold, Bell Canyon, CA (US);
H Maurice France, Palos Verdes Estates, CA (US);
Gazelle Graphic Systems Inc., Irvine, CA (US);
Abstract
Disclosed is electromagnetic transducer that does not require complex analog to digital, digital to analog converters, microprocessors or large memory circuitry. The transducer has a helical tablet coil with tap nodes spaced between its end extremities. In one configuration, an oscillator drives the tablet coil for simultaneously producing oppositely directed currents on opposite sides of selected taps, creating a moving fringing field that is compatible with modern graphic display tablet technology. A control circuit of the transducer has a closed-loop integrator for detecting the centroid of a received stylus signal from a stylus coil. Analog and digital versions of the integrator are disclosed. In another configuration, the oscillator drives the stylus coil for variably coupling magnetic flux to the tablet coil, a receiver signal that is coupled from the end extremities being responsive to the position of the stylus coil and the taps selected. A preferred configuration of the tablet coil has separate oppositely wound coil components.