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:
May. 23, 2000
Filed:
Mar. 15, 1996
John D Fergason, Mountainview, CA (US);
OSD Envizion, Inc., St. Louis, MO (US);
Abstract
An integral indicator or display for a welding lens, which has a twisted nematic liquid crystal cell light shutter, includes plural independently operable twisted nematic liquid crystal cell indicator portions integral with the light shutter twisted nematic liquid crystal cell, indicia associated with respective indicator portions to indicate an operating characteristic of the welding lens, circuitry for operating the lens and the indicator portions, and one or more switches for stepping the circuit through respective settings of operating characteristics, such as shade darkness, sensitivity and delay time. The indicator is dark when the light shutter is dark, and the light shutter may include in optical series with the twisted nematic liquid crystal cell, a birefringent liquid crystal cell light shutter which is faster acting than the twisted nematic liquid crystal cell and can be driven to various shades at respective speeds depending on applied electric field. A method of protecting the eyes of a welder includes selecting an operating characteristic of a welding lens and using a display portion of the welding lens to display an operating characteristics of the welding lens.