Method for performing Raman spectroscopy within a logging while drilling instrument

A logging while drilling tool, comprising:

• a tool body having a plurality of blades extending radially outward from a longitudinal axis of the tool body, wherein the plurality of blades have an outer diameter that is larger than a borehole diameter;
• at least one cavity formed in at least one blade of the plurality of blades, wherein the at least one cavity extends from an opening of the at least one cavity at an outer surface defining the outer diameter of the at least one blade to a closed end within the at least one blade, wherein at least a portion of the at least one blade separates the closed end of the at least one cavity from the tool body, wherein the at least one cavity has a Raman spectroscopy system for determining maturity in a formation sample, and wherein the Raman spectroscopy system comprises:
• a light source mounted in the at least one cavity;
• a light detector mounted in the at least one cavity, wherein the light source and the light detector are configured to take back-scatter measurements;
• a filter mounted in the at least one cavity, wherein the filter is disposed on top of the light detector and covers the light detector, and wherein the filter is disposed closer to the opening of the at least one cavity than the light detector;
• at least one window disposed at the opening of the at least one cavity, wherein the at least one window encloses the at least one cavity;
• and
• at least one cooling device mounted in the at least one cavity and configured to cool the light source or the light detector.