Among the simulated devices, some cases of both under-and over-estimation were observed, perhaps because there are reasons for either to occur. The model could underestimate efficiency since it assumes the sample holder absorbs all rays, while in practice the mask may reflect a fraction of rays. On the other hand, it could overestimate efficiency due to lack of control over surface properties and imperfections, use of a constant waveguide background absorption, and the assumption of 100% PLQY, which is unrealistic in devices based on LR305. A combination of these factors could explain why the model underestimates in certain cases while overestimating in others.