Laser projection displays are commonly used for stage backdrops and promotional display markets. It has advantages such as high contrast, the “absence of light” in dark regions of the scene and enables displaying of visual content in a large screen environment which can lead to emotional perception.

The aim of this project is to create a monochromatic laser projection display that is able to project any shapes or words. This can be achieved by scanning and controlling a laser beam in two perpendicular directions along a plane parallel to projection wall. To do this, it will require the design of electronic systems for optical scanning and beam control. In addition, the projector will be controlled via the computer which acts as a software interface to accept graphical input to be displayed.

The projector would be made up of mainly, laser diode which acts as the source, and two stepper motors with mirrors attached controlling the X-axis and Y-axis respectively. The motor rotation will be driven by the microcontroller, which obtained the coordinates from the software interface and synchronised the output to the motors and laser. From the rotational angle of the stepper motors, the desired coordinates of the laser beam can be displayed. For better results, we need to produce a projected image of 30Hz or above.

Annie Ka Yin Lau, Dr Thas A Nirmalathas, Chung-Charn Or