Patent ID: 6791765
Filing Date: 2004-09-14
Classification: G02B

Abstract:
A retrofocus wide-angle lens formed of only three lens groups, in order from the object side, a first lens group of negative refractive power, a second lens group that includes a stop, and a third lens group of positive refractive power; whereinsaid first lens group is at the object end of the retrofocus wide-angle lens and includes, in order from the object side, a plurality of negative lens components and a plurality of positive lens components, and said first lens group includes a lens group of negative refractive power that is at the object end of the first lens group and that includes said plurality of negative lens components and at least one of the plurality of positive lens components of said first lens group; said first lens group further includes a first another lens group of negative refractive power that is on the image side of and adjacent to said lens group of negative refractive power that is at the object end of the first lens group, and said first another lens group includes at least one positive lens component; said first lens group includes a second another lens group that is on the image side of and adjacent to said first another lens group, and said second another lens group includes, in order from the object side, a positive lens element and a negative lens element that are intimately bonded to one another; and said second lens group includes a lens component that is adjacent to said stop and that includes a positive lens element that is intimately bonded to a negative lens element.