In the last decades, the optical adhesives have become highly promising due to their widespread applications in the numerous optical fields. There are outnumbered research studies about them and their numerous fields of application. One of these promising applications is the usage of self-written waveguides (SWW) which enable a rigid and low loss connection between two optical components. Nevertheless, there are not enough research studies about the temperature dependency of the optical transmission through the SWW that is inspected in this study. This master’s project is devoted to study the transmission of a laser beam by temperature through SWW created in the NOA 68 photopolymer medium. To verify the data from the experiment, a model is designed, simulated using the Multiphysics optical simulation software (COMSOL), and then, the simulation results are compared with the experimental data. Furthermore, the research studies do not propose anything for the durations of the internal- and external curing where the waveguide is attenuated highest that makes it very vital for the waveguide formation. This study removed the blurriness in the curing times and guide the scientists in establishing an efficient waveguide made out of NOAs. To achieve this goal, a thermal simulation of the waveguide is made, an SWW is formed, and the experimental results of the power output, and the refractive-index profile of the waveguide are analyzed. Then, the RIs of the SWW and its cladding are measured in the refractive-index profilometer and the results are used to make the simulation in the software.