A display apparatus comprises: an emissive spatial light modulator
comprising an array of pixels each arranged to output randomly polarized
light; a birefringent lens positioned to receive light from the spatial
light modulator arranged in a first mode of operation of the display
apparatus to direct light of a first polarization component into a first
directional distribution and in a second mode of operation of the display
apparatus to direct light of a second polarization component into a
second directional distribution different from the first directional
distribution; a quarter waveplate; and a linear polarizer. The quarter
waveplate is arranged between the spatial light modulator and the
birefringent lens and the linear polarizer is arranged on the opposite
side of the birefringent lens from the quarter waveplate.