| 摘要 |
PROBLEM TO BE SOLVED: To achieve an unconventional image display device that has a wide angle of view of projection images.SOLUTION: An image display device projects an image for projection displayed on an image display element on a projection target surface to be displayed in an enlarged form, and a zoom lens for projection used as a projection optical system has a five-lens group structure consisting of a first lens group G1 to a fifth lens group G5 arranged from the enlargement side toward the reduction side, where the first lens group G1 has a negative refractive power; the second lens group G2 has a negative refractive power; and the third lens group G3 has a positive refractive power; and when a half angle of view at the wide angle end is ωw, a focal distance of the first lens group is f1, and a focal distance of the second lens group is f2, the conditions (1): 34 degrees≤ωw<45 degrees and (2): 0.1<f1/f2<1.0 are satisfied. |
