Or worse, you may get a product with unwanted bugs features, like some green lasers that ... a thorough exploration of a wide range of cheap (and not so cheap) lasers in the video below.

The green laser beam thus behaves like an object, blocking the blue light and casting a dark line across the screen. That dark line meets all the criteria for a shadow: it was visible by eye ...

These are used in a wide variety of applications, from data storage to scientific research. However, a laser diode that directly emits green light at 520–530 nm, the desired wavelength for green ...

They shone a green laser beam through the cube while illuminating it perpendicularly with blue light. When the green laser passed through the ruby crystal, it created a region that absorbed more ...