Is actually a microscope, and it doesn't use light but uses electrons.
This is a sample of CIGS (CdInGaSe) which is the newish cheap way to make solar cells.
This is an attached x-ray spectrometer which looks at the energies of the x-rays that spew off of the sample b/c of the electrons that are bombarding it. It can be used to determine what materials are being looked at because each element gives off a special spectrum which is like a fingerprint of that element.
Here is what is inside an LED. There is a gold (Au) ball bond (it's squished) on the top colored in yellow. Red is gallium (Ga), and blue is arscenide (As) which is what makes up the material that actually shines light and you can see there is a bunch of Ga at the top, and a mixture (purple) towards the bottom. The teal is silver (Ag) that electrically and thermally connects the whole thing to the lead at the bottom in red which is made of iron (Fe).