I have been playing with Arduinos for about a year now, and I noticed that none of my projects were really utilizing the speed capabilities of the ATmega328 chips. At 16 MHz, they can do a hell of a lot more than blink LEDs. To improve my appreciation of their capabilities, I wanted to build a project which required very fast and precise timings. That is what motivated me to build a persistence of vision alphanumeric laser projector.
My projector uses a single laser and has only one moving part. 6 mirrors are hot glued to a spinning platform. Each mirror is at a slightly different angle, and each is responsible for 1 of the 6 lines of vertical resolution. One full rotation sweeps the laser across the target 6 times at 6 different heights. An optical sensor detects the start of a rotation and times the laser pulses to produce readable text.
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.