A method of manufacturing color filter comprising the steps of forming a metal layer and a photoresistor layer on a substrate; defining a dent over the photoresistor layer and removing the metal layer below the dent; depositing an optical filter material over the resulting structure at relative high temperature, lift off the photoresistor layer by etching the metal layer. The optical filter material can be fabricated at higher temperature (300-400° C.) than conventional cold process, the extinction ratio of the filter made by the optical filter material can be as high as 90% to enhance the performance of the projector system.