Q: What are diffraction gratings? A diffraction grating is an optical component for spectroscopy that splits light into different wavelengths. A typical diffraction grating has thousands of ...

Diffraction gratings separate different wavelengths of light using a periodic pattern embedded in the grating. The diffraction pattern can affect the amplitude and/or phase of the incident light as ...

The pattern may be bigger, and red light is likely less sensitive to imperfections in the grating. Some of the special edition banknotes in circulation don't have the maple leaf diffraction grating.

Sure, a hacker could make one if he or she put their mind to it. But make one out of a webcam, some cheap diffraction grating purchased off ebay and some scrap? Surely not. [Renaud] pulls off this ...