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:
Sep. 05, 1995
Filed:
Jun. 23, 1994
Bruce T Williams, Lockport, NY (US);
Other;
Abstract
A high spatial resolution low noise method and apparatus for determining electrical characteristics such as the voltage density distribution or the charge density distribution of an electrophotographic medium having a surface and capable of holding electrical charge wherein a sensor is provided in close proximity to the surface, electrical charge is applied to the surface, relative movement is caused between the surface and an edge of the sensor, a substantially zero voltage difference is maintained between the sensor and the surface, there is detected a signal induced on the sensor edge in response to variation in the voltage or charge on the surface as it crosses the sensor edge, and an electrical parameter of the signal is measured to provide information on the variation of the voltage or charge on the surface to determine the voltage density distribution or the charge density distribution on the surface. The foregoing eliminates the requirements of selecting a sensor area to be sufficiently small and holding the spacing between sensor and surface constant to reduce noise, while obtaining the advantages of increased signal strength and increased measurement resolution.