To enhance the net photoelectric conversion efficiency of quantum well infrared photodetectors， this study investigates the matching conditions between radiative dissipation and coupling strength in devices operating in the strong light-matter coupling regime. A critical coupling model distinct from the conventional intrinsic and radiative dissipation matching is proposed. Through an analytical model， the contributions of intrinsic thermal dissipation and coupling strength to the critical conditions are quantified. The results indicate that， with optimized matching parameters， the net photoelectric absorption efficiency， excluding thermal dissipation， can exceed 95%. Moreover， under the synergistic regulation of the strong coupling mechanism and critical coupling conditions， the photodetection response can be enhanced by up to 160%. This work highlights the importance of optimizing dissipation and coupling parameters under strong coupling conditions， providing theoretical and design guidance for improving photoelectric conversion efficiency and enhancing the performance of quantum well infrared photodetectors.