Process for producing optical element

A process for producing an optical element comprising a liquid crystal layer part, which causes a phase difference upon incidence of light, and an isotropic layer part, which does not cause a phase difference upon incidence of light, said liquid crystal layer part and said isotropic layer part having been patterned in a desired form, said process comprising the steps of:

• coating a coating liquid comprising a polymerizable liquid crystal onto a base material to form a coating film;
• aligning said polymerizable liquid crystal to a liquid crystal phase state;
• applying an ionizing radiation to said coating film through a photomask to polymerize said polymerizable liquid crystal in the liquid crystal phase state, whereby said polymerizable liquid crystal only in its exposed part is cured to form said liquid crystal layer;
• and
• heating the resultant substrate with the coating film formed thereon to bring the polymerizable liquid crystal in the uncured state to an isotropic phase state and, in this state, to polymerize the uncured polymerizable liquid crystal to form an isotropic layer.