A power generator for taking out electric power from a pyroelectric part by changing temperature of the pyroelectric part exhibiting a pyroelectric effect is disclosed. The method includes: immersing grains in water and removing the water therefrom; grinding the grains from which water is removed, adding water thereto, and then grinding the grains to which water is added; steaming the ground grains; and cooling the steamed grains, adding flour thereto, and then punching the resultant product. The assembly is then encapsulated with resin and shielded by metallization. A focus mechanism may automatically set the 2D focus distance and the 3D focus distance to be essentially equal by one of adjusting the first lens based on the 3D focus distance and synchronously adjusting the left and right lenses based on the 2D focus distance. The generated output signal may be multiplexed on at least one pin on the chip and it may comprise a clock signal andor a data signal. If, in this state, a right-hand push-button switch is shifted to a second OFF state, a normally close contact R3-1 of the right-hand push-button switch is opened.