Optical communication device

An optical communication device comprising:

• a collimating lens;
• a spectral element that is provided for wavelength separation of light transmitted through the collimating lens;
• and
• a spatial modulation element that modulates the light subjected to the wavelength separation by the spectral element,
• wherein the collimating lens is a liquid crystal diffractive lens element having an optically anisotropic layer formed of a composition containing a liquid crystal compound,
• the optically anisotropic layer of the liquid crystal diffractive lens element has a liquid crystal alignment pattern in which an orientation of an optical axis derived from the liquid crystal compound changes while continuously rotating toward one direction, in a radial shape from an inside toward an outside,
• in the liquid crystal alignment pattern, in a case where a length over which the orientation of the optical axis derived from the liquid crystal compound rotates by 180° in the one direction in which the orientation of the optical axis derived from the liquid crystal compound changes while continuously rotating is set as a single period, the length of the single period gradually decreases from the inside toward the outside, and
• the optical communication device acts as an optical switching system.