| 摘要 |
A zoom lens and a projector unit are provided to realize a compact and bright image having a high-quality as well as to be suitable for characteristics of a light bulb such as a DMD(Digital Micromirror Device). A lens group includes a first lens group(LG1), a second lens group(LG2), and a third lens group. The first lens group has positive or negative refractive power. The second lens group has the negative refractive power. The third lens group has the positive refractive power. While a magnification varying operation is in effect, the first lens group is fixed to the left. In the same case, the second lens group moves on an optical axis in such a way of moving in a direction from a magnification side to a contraction side in a range from a wide angle end to an intermediate area and moving in a direction from the contraction side to the magnification side in a range from the intermediate area to a telephoto end and the third lens group moves on the optical axis in such a way of moving in a direction from the contraction side to the magnification side in a range from the wide angle end to the telephoto end.
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