Abstract: A method for compensating for frequency shifts caused by variation in an environmental parameter of an atomic clock is provided. A preset reference voltage of a proportional integral differential amplifier is set so that an offset frequency shift is generated in locking frequency of a laser. Then, the preset reference voltage is optimized by correcting the frequency shift coefficient to obtain an optimal reference voltage. A non-peak point of the resonance spectral line of the atomic clock is locked, so that the variation in the offset frequency shift caused by power variation of an optical signal output by the laser can compensate for the variation in the locking frequency of the laser caused by the power variation, thereby reducing the frequency shift coefficient caused by the power variation. The method is simple to operate and has universality.

Abstract: A method of forming an electronic device having a metal piece and a plastic piece adhered to the metal piece is provided. The method includes the step of forming an adhering part on a surface of the metal piece which at least partially covers the surface thereof. The method also includes the step of forming the plastic piece by injection molding using a plastic material which is adhered to the metal piece with the adhering part connecting the plastic piece and the metal piece.