You’ll also need a focusing lens (just a few dollars), some thermal glue, an LM317, a resistor, and a pair of protective goggles matching the laser diode’s wavelength. He fits the diode into ...

Fresnel lenses consist of a flat surface with interspaced, concentric steps whereby each step corresponds to the surface of a conventional lens. Each step thereby acts ... circular apertures and can ...

Welcome back to part II in this ensemble of techniques with laser-cut Delrin ... where we focus the lens prior to cutting will determine the shape of the lens–unless we cut our part in multiple ...

Fresnel lenses, however, don’t require curvature of any kind, but instead utilize concentric flat rings to diffract light, with the rings’ size and width determining the overall lens focal length.

Fresnel lenses consist of a flat surface with interspaced, concentric steps whereby each step corresponds to the surface of a conventional lens. Each step thereby acts as a refractive surface, much ...

In particular, using a Fresnel lens coupled with a laser to fuse lunar regolith would reduce the power (and thus size, weight, etc.) of the laser astronauts would need to tote along, the study finds.