ILLUMINATION OPTICAL SYSTEM AND IMAGE PROJECTION DEVICE

摘要

PROBLEM TO BE SOLVED: To fix a lens located on a path from a light source to an image forming element, with higher accuracy.SOLUTION: An illumination optical system includes: a lens part arranged on a path to an image forming element where emitted light forms an image; a holding part which holds the lens part; and an elastic part mounted on the holding part and integrated with a first portion which is biased in an optical axis direction of the light and pressing the lens part and a second portion which is biased in a direction orthogonal to the optical axis direction and pressing the lens part.