The objective of this project was to improve our Planar Laser Rayleigh Scattering (PLRS) test diagnostic and utilize it to characterize the temperature gradient and cooling film effectiveness of a set of effusion cooling configurations in gas turbine combustors. Effusion Cooling, a cooling technology utilized by Pratt & Whitney, is the technique of interest for this project and is an array of angled holes that allow coolant flow through the combustor liner and creates a protective film above the liner surface. Altering the geometry and patterns of effusion cooling holes can improve cooling performance and PLRS testing allows us to quantify and compare performance between configurations. The laser beam expanding optical setup was completely redesigned and implemented to improve PLRS, operating as a Galilean telescope and forming a laser sheet to cover the entire effusion array. This new setup will be used in an upcoming PLRS test campaign to test six thermal barrier coated and five uncoated effusion configurations and characterize their near-wall temperature gradient and cooling film effectiveness. Infrared Thermography (IR) testing was also done as a part of this project on these 11 configurations to obtain surface temperatures and cooling effectiveness data. This IR data coupled with PLRS data will allow us to identify high performing configurations and help Pratt & Whitney to further develop effusion cooling technology.