Zoom lens and image projection apparatus including the same

An image display device, comprising:

• a zoom lens;
• and
• an image display element configured to form an original image projected by the zoom lens
• wherein the zoom lens comprising:
• a first lens unit having negative refractive power that is not moved during zooming;
• plural lens units that are moved during zooming;
• a final lens unit having positive refractive power that is not moved during zooming;
• wherein
• a final moving lens unit having positive refractive power and disposed nearest to the reduction conjugate side among the plural lens units that are moved during zooming is moved toward the enlargement conjugate side during zooming from the wide angle end to the telephoto end, and
• the final moving lens unit includes one or more negative lenses and one or more positive lenses and one negative lens of the one or more negative lenses and one positive lens of the one or more positive lenses are cemented with each other;
• and
• the following conditions are satisfied:
• 5.00<f/fw
• lnn−npl<0.080
• 0.0<νn−νp
• where
• f is a focal length of the final moving lens unit;
• fw is a focal length of an entire system at a wide angle end;
• nn and νn are respectively an average refractive index and an average Abbe number of a material of the one or more negative lenses at is included in the final movement lens unit;
• np and νp are respectively an average refractive index and an average Abbe number of a material of the one or more positive lenses included in the final moving lens unit,
• provided that, when a refractive index for C-line is denoted by NC, a refractive index for d-line is denoted by Nd, and a refractive index for F-line is denoted by NF, the Abbe number ν=(Nd−1)/(NF−NC).