| 摘要 |
PROBLEM TO BE SOLVED: To obtain a zoom lens which is short in overall zoom system length when stored, and at the wide-angle end and telephoto end and also has its aberrations excellently corrected although the power variation rate is high by composing the zoom lens of five groups and satisfying specific conditional expressions. SOLUTION: This zoom lens has the five lens groups G1 to G5. The 1st lens group G1 is composed of a negative meniscus lens which is very concave to the object side. The 5th lens group G5 is composed of a positive meniscus lens which is concave to the image side and a negative meniscus lens which is very concave to the object side. Then, 0.02<|fL|/fT<0.3, 0.1<ΔXtLT/fT<0.7, and 1.5<βLT/βLW<6.0 hold. Here, fL is the focal length of the final lens group, fT the focal length of the whole system at the telephoto end,ΔXLT the zooming movement quantity of the final lens group up to the telephoto end,βLT the lateral power of the final lens group at the telephoto end, andβLW the lateral power of the final lens group at the wide-angle end.
|
