There is a caveat: it will not show the picture in high resolution.
Ben from Ben Makes Everything made a compact laser projector out of an old hard drive. The device had to be heavily modified: the projector would definitely not fit into the old case.
The idea behind the projector is simple: a laser shines on an array of mirrors mounted on a hard drive spindle. By controlling the laser and rotating the mirrors, letters and other symbols can be drawn with reflected light. It turned out to be more difficult to implement the idea.
For example, says Ben, he managed to construct a suitable array of mirrors only from the third time. The engineer decided to settle on a green laser: this spectrum was chosen due to its power and visibility.
The final version of the projector runs on batteries and can project text messages up to 90 feet away – that’s about 27 meters. You can send messages remotely, the projector supports Bluetooth connection.
This is interesting