Abstract: A liquid crystal optical device includes multiple liquid crystal elements arranged along the optical axis. Each liquid crystal element includes two transparent electrodes that are disposed so as to face each other with a liquid crystal layer disposed therebetween. At least one of the two transparent electrodes includes multiple partial electrodes. For each of a predetermined number of levels obtained by dividing, by the predetermined number, difference between a maximum value and a minimum value of a phase modulation amount provided to a luminous flux passing through the liquid crystal layer, at least one of the multiple partial electrodes is disposed on a part of the liquid crystal layer, the part providing the luminous flux with a phase modulation amount corresponding to the level. A position of the boundary between any two adjacent partial electrodes with respect to the luminous flux, is different for each liquid crystal element.