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:
Oct. 09, 2001
Filed:
Nov. 08, 1999
Melvyn H. Kreitzer, Cincinnati, OH (US);
Corning Precision Lens, Cincinnati, OH (US);
Abstract
Projection lens systems (,) for use in CRT projection televisions (,) are provided. From the screen side, the systems have three lens units (U,, U,, U,), the first two units (U,, U,) forming a retrofocus lens and the third unit (U,) being associated with the CRT during use and serving to correct field curvature. At its screen end, the first lens unit (U,) has a negative element (E,) which has a screen surface (S,) which is concave to the screen. The second lens unit (U,) has two positive subunits (U,, U,), the first subunit (U,) being a color correcting doublet composed of glass and the second subunit having a positive lens element (E,) at its screen end. The projection lens systems are fully color corrected, have f/#'s of 1.0 for an infinite conjugate, have half fields of view of at least 25°, and are economical to manufacture.