| 摘要 |
PROBLEM TO BE SOLVED: To provide a wide-angle lens suitable for a recent high pixel imaging device. SOLUTION: This wide-angle lens A is constituted by arranging a 1st lens having positive refractive power and also set so that both surfaces are made aspherical, a 2nd lens 2 having negative refractive power, a 3rd lens 3 bonded with the 2nd lens 2 and having positive refractive power, a 4th lens 4 having positive refractive power and also set so that its one surface is made aspherical and a glass lens 5 such as a low-pass filter in order from an object side, and satisfies conditions of (1) and (2). (1) 0.7×|r4|<|r6|<1.3×|r4|, (2)ν1<35,ν2<ν3,ν4>50. Provided that r4 means the radius of curvatuer of the surface of the 2nd lens 2 on the object side, r6 means the radius of curvature of the surface of the 3rd lens 3 on an image surface side, andν1 toν4 are the Abbe numbers of the lenses 1 to 4.
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