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:
Aug. 27, 2013
Filed:
Jul. 18, 2011
Tsan-haw Lee, Taichung, TW;
Tsan-Haw Lee, Taichung, TW;
Asia Optical Co., Inc., Taichung, TW;
Abstract
A zoom projection lens includes a first lens set and a second lens set arranged in sequence from an object side to an image side of the zoom projection lens. The first lens set has a negative optical power. The second lens set has a positive optical power. The first lens set has a first lens. The second lens set has a second lens, a third lens, a fourth lens, and an aperture stop disposed between the second lens and the third lens. The first lens is an aspherical plastic lens. One of the third and fourth lenses is an aspherical glass lens. The zoom projection lens satisfies: 1.463<|tt/lt|<1.505, in which, tt represents an overall length of the zoom projection lens, and lt represents a length of the zoom projection lens from the object side of the first lens to an image side of the fourth lens.