The basic components of a Raman instrument are a laser, a sample compartment where laser light is focused in the sample and where scattered light is collected, a spectrometer and a detector for measuring the spectrum of the scattered light, and a PC for instrument control and (real-time) data-analysis.
The sample compartment of a Raman microspectrometer is an optical microscope (the microscope objective is used to focus laser light in the sample and to collect scattered light from the sample). This enables Raman spectra to be obtained with the same sub-micron spatial resolution as is common in optical microscopes.
Optical fibers can be used to guide laser light to the sample and to guide Raman scattered light back to the spectrometer. In this way, fiber optic Raman probes enable laser and spectrometer to be located remote from the sample, and to bring the instrument to the sample instead of bringing the sample to the instrument.This is, of course, a requirement for many in vivo applications.