Most lasers emit photons of exactly the same wavelength, producing a single color. However, there are also lasers that consist of many frequencies, with equal intervals in between, as in the teeth of a comb; thus, they are referred to as "frequency combs." Frequency combs are perfect for detecting a variety of chemical substances.
Chemical
December 11 2018 3:25 pm
December 11 2018 3:25 pm