PURPOSE: To form an engraved design simply and in a short time by a method wherein laser rays, heat rays from an arc lamp, etc. are irradiated on the surface of a work such as a wood plate, etc. through a made, a shield with holes hollowed out with designs.

CONSTITUTION: A heat resisting mask 3 hollowed out with designs 2 is placed on a work 1 mask from wood, plastics, etc. Then, laser rays 4 are irradiated all over the surface as they are moved. Thus, the portion under a design engraved hole 2 is burnt off by the laser rays to form a concave portion 5. The depth of the excavated concave portion 5 is free to be changed by adjustment of energy. Not only laser rays but arc light or electric pulses may be used as the ray. The surface of the work can be varied delicately and remarkably stricking designs can be obtained by graduation and material of ink color on a shield.