This thesis proposes the use of Arduino as the basis of the control element, and the controlled laser light to achieve the projection effect. Arduino first write the program will be required text and symbols into the database, and write the text display. Then the circuit associated with the display component is washed into a circuit board, and the laser diode and other components are soldered to the portion where the circuit is completed. Drawing solidworks laser diode base model, Solidworks is a computer-aided drawing software, used to make this part of the 3D printing. Finally, the laser diodes are fixed to the base one by one and the optical path is adjusted to achieve the desired projection effect, and the result is made into a simple finished product.