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. 27, 2011
Filed:
May. 09, 2006
Janez Pirs, Ljubijana, SI;
Silvija Pirs, Ljubljana, SI;
Bojan Marin, Ljubljana, SI;
Andrej Vrecko, Ponikva, SI;
Janez Pirs, Ljubijana, SI;
Silvija Pirs, Ljubljana, SI;
Bojan Marin, Ljubljana, SI;
Andrej Vrecko, Ponikva, SI;
Institut Josef Stefan, , SI;
Abstract
A new concept of the LCD light-switching optical filter allowing for very high, electrically controlled, continuously variable light attenuation (up to ≧100.000) optimized/symmetrized for the light incidence along the normal to the LCD plane is proposed. The new LCD light-switching optical filter also exhibits very low light attenuation dependence for the oblique incidence of light within a limited cone of angles off the normal incidence direction in compliance with the international safety and quality regulation EN 379 for personal protection equipment. According to the invention the problem is solved by specific, novel modification of the general principle of highly twisted nematic LCDs, allowing for the adaptation of the light transmission/driving voltage characteristics to specific requirements of the driving electronics as well as 'symmetrizing' the overall optical birefringent properties, which in turn results in a high degree of their angular compensation.