We’ve read a lot about oscillators, but crystal oscillators seem to be a bit of a mystery. Hobby-level books tend to say, build a circuit like this and then mess with it until it oscillates.

Crystal oscillators are incredibly useful components, but they come with one little snag: their oscillation is ...

Optical parametric oscillators (OPOs) are convenient sources of coherent light that suit numerous scientific applications, including various types of ... use a nonlinear crystal to convert a ...