Patent ID: 6888682

Claim:
A projector lens system that projects and enlarges an image from a light bulb of a projector display device, wherein said projector lens system comprises a negative first lens group and a positive second lens group, in this order from the projection side; wherein said negative first lens group comprises a first lens element that is formed as a negative meniscus lens element having the convex surface facing toward the projection side, a positive or negative second lens element, a negative third lens element, a positive fourth lens element that is cemented to or separated from said third lens element, and a negative fifth lens element, in this order from the projection side; and wherein said negative first lens group satisfies condition (1) with respect to the refractive power thereof, and satisfies condition (2) with respect to the refractive power of said negative first lens element of said negative first lens group: 0.6< f w /|f I |<1.0â€ƒâ€ƒ(1) ( f I <0) 0.3< f I /f 1,1 <0.7â€ƒâ€ƒ(2) wherein f w designates the focal length of the entire projector lens system at the wide-angle extremity; f I designates the focal length of said negative first lens group; and f 1,1 designates the focal length of said negative first lens element of said negative first lens group.