| 摘要 |
<p>The purpose of the present invention is to provide a projection zoom lens which takes size reduction into account, has an increased zoom ratio, has the entire zoom range brightened, and has aberrations satisfactorily corrected, and to provide a projection device using the projection zoom lens. A first lens group (G1) having fixed positive refractive power when magnification is changed is disposed at a maximum enlargement side. A final lens group (Ge) having fixed negative refractive power when magnification is changed is disposed at a maximum reduction side. A plurality of lens groups (Gm) are disposed between the first lens group (G1) and the final lens group (Ge) and move in correlation along an optical axis when magnification is changed, in order to correct the change in magnification and image surface drift generated by the change in magnification. A lens having positive refractive power is disposed at the maximum reduction side of the final lens group (Ge).</p> |
