An illumination optical system of the present invention includes a first lens array FE including a plurality of lens cells dividing a light flux emitted from a light source into a plurality of light fluxes, a second lens array MLAi including lens cells on which spot lights exiting from the lens cells included in the first lens array FE are condensed, and a first optical member IL3 imaging the spot light, which has been condensed on the lens cell included in the second lens array MLAi, on one of optical modulation elements constituting an optical modulation unit.

An illumination optical system of the present invention includes a first lens array FE including a plurality of lens cells dividing a light flux emitted from a light source into a plurality of light fluxes, a second lens array MLAi including lens cells on which spot lights exiting from the lens cells included in the first lens array FE are condensed, and a first optical member IL3 imaging the spot light, which has been condensed on the lens cell included in the second lens array MLAi, on one of optical modulation elements constituting an optical modulation unit.

An illumination optical system of the present invention includes a first lens array FE including a plurality of lens cells dividing a light flux emitted from a light source into a plurality of light fluxes, a second lens array MLAi including lens cells on which spot lights exiting from the lens cells included in the first lens array FE are condensed, and a first optical member IL3 imaging the spot light, which has been condensed on the lens cell included in the second lens array MLAi, on one of optical modulation elements constituting an optical modulation unit.