A light modulator element suitable for a laser microscope, an optical pick-up device or a laser-processing machine, said light modulator element comprising: a first liquid crystal element (2,7) which comprises a first liquid crystal layer containing liquid crystal molecules aligned along a first direction in a state where an electric voltage is not applied; two first alignment layers (25,26) which are disposed in opposition to each other with said first liquid crystal layer sandwiched therebetween and align the liquid crystal molecules along the first direction; and two first transparent electrodes (23,24,71) disposed in opposition to each other with said first liquid crystal layer and said two first alignment layers (25,26) sandwiched therebetween; wherein the first liquid crystal element (2,7) is adapted to control the phase of linearly-polarized light of a prescribed wavelength passing through said first liquid crystal layer by applying an electric voltage in accordance with said prescribed wavelength between said two first transparent electrodes; a polarizer plate which is disposed on a side where said linearly-polarized light is incident on said first liquid crystal element (2,7) and whose transmission axis lies along said first direction or along a direction orthogonal to said first direction; and a rotation mechanism, characterized in that said rotation mechanism comprises a casing and a rotational support member supporting said first liquid crystal element and said polarizer plate and being rotatable as a single unit along with said first liquid crystal element and said polarizer plate about the optical axis of said first liquid crystal element in said casing, wherein said polarizer plate is supported removably by said rotational support member. a first liquid crystal element (2,7) which comprises a first liquid crystal layer containing liquid crystal molecules aligned along a first direction in a state where an electric voltage is not applied; two first alignment layers (25,26) which are disposed in opposition to each other with said first liquid crystal layer sandwiched therebetween and align the liquid crystal molecules along the first direction; and two first transparent electrodes (23,24,71) disposed in opposition to each other with said first liquid crystal layer and said two first alignment layers (25,26) sandwiched therebetween; a first liquid crystal layer containing liquid crystal molecules aligned along a first direction in a state where an electric voltage is not applied; two first alignment layers (25,26) which are disposed in opposition to each other with said first liquid crystal layer sandwiched therebetween and align the liquid crystal molecules along the first direction; and two first transparent electrodes (23,24,71) disposed in opposition to each other with said first liquid crystal layer and said two first alignment layers (25,26) sandwiched therebetween; wherein the first liquid crystal element (2,7) is adapted to control the phase of linearly-polarized light of a prescribed wavelength passing through said first liquid crystal layer by applying an electric voltage in accordance with said prescribed wavelength between said two first transparent electrodes; a polarizer plate which is disposed on a side where said linearly-polarized light is incident on said first liquid crystal element (2,7) and whose transmission axis lies along said first direction or along a direction orthogonal to said first direction; and a rotation mechanism, characterized in that said rotation mechanism comprises a casing and a rotational support member supporting said first liquid crystal element and said polarizer plate and being rotatable as a single unit along with said first liquid crystal element and said polarizer plate about the optical axis of said first liquid crystal element in said casing, wherein said polarizer plate is supported removably by said rotational support member.