Timothy Giles has developed a 3D-printed optical cavity designed to detect minute shifts in space and wavelength. By arranging two semi-transparent mirrors—one on a printed mount and the other attached to a speaker diaphragm—the setup uses light interference to measure displacement at a nanometer scale. A webcam monitors an emitted beam pattern for alignment, while the speaker acts as a linear actuator to vary cavity length. This experiment also demonstrates how thermal shifts in a laser diode can cause wavelength instability through changing interference patterns.
- 3D printing construction of optical cavities
- Measuring displacement via light interference
- Utilizing a speaker diaphragm as an actuator
- Observing temperature-induced laser wavelength fluctuations
Han has created a 512-bit magnetic core memory module and documented the process, including wiring details and oscilloscope traces. The module has passed extensive testing, demonstrating the reliability of ferrite memory. The article details the principles of magnetic core memory and provides links to resources for building your own.
This article details a DIY atomic force microscope built from mostly junk parts. It utilizes a laser-based deflection reading system instead of traditional piezo motors, achieving 35-um resolution with readily available materials. The project focuses on simplicity and cost-effectiveness, making it suitable for educational purposes.
Glowtape is a unique DIY wristwatch by Henner Zeller that uses glow-in-the-dark tape and an RP2040 microcontroller to display the time.