Inexpensive Methods of Open Loop Scanners to Create Geometric Laser Light Patterns
  1. Using two DC motors to create Laser patterns. Two, inexpensive DC motors, with mirrors attached to the front of the shafts at a 90-degree angel.
    The motors should be placed at 90-degrees from each other so that the Laser can bounce off the the one mirror and then the other.
    Rotation of the two mirrors at different speed, will produce some basic Lissajou, Laser lite show patterns.
    Three  motor, with the Laser beam bouncing between all three motors, will increase the amount of Laserlightshow patterns patterns, one can create with this configuration.
  2. Another approach is using a DC motor with a spring, attached to the shaft.Again in the same X -Y  configuration. This attenuates the motor and prevents it from turning a fill 360o.
    The, shaft is only allowed to travel 25o, of it's mechanic rotation.
    In, this case, mirrors are also attached to the shaft and with the introduction of a sign wave induced into the two motors, a host of different geometric Lissajou, type patterns.
    If, these scanner are tuned correctly, will be able to produce some special geometric patterns, like a 6 pointed star.
  3. Speaker coils, are another way of achieving geometric laser light patterns.
    When, two speaker coils are affixed in a X - Y configuration, at 90o apart, they will produce the best types of geometric patterns from an inexpensive, source. 
    Again, mirrors are attached to the coil around a magnet. The coil produces a electromagnetic field that is drawn to the magnet, on and off, which causes the mirror to move back and forth very rapidly.
    Laserworks, offers this type of scanner as a kit. Under the Heading of  Scanners SS-150-OL and the controller LLG-150.
  4. One, other method, is to stretch a thin membrane across the top of a speaker, add a mirror in the center of the of the membrane.  
    When a voltage is applied to the speaker, it will vibrate and cause the Laser beam shining off the first surface mirror to dance about in abstract, shapes, in time to the music.