Surface plasmon resonance (SPR) sensors are widely employed for biochemical detection owing to their sensitivity and label‐free capability. However, conventional angular interrogation SPR configurations are often constrained by an inherent trade‐off between angular sensitivity and dynamic measurement range, which limits their practical performance. The present study addresses this limitation by introducing a geometry‐driven angle mapping framework that explicitly links the externally controlled gauge angle to the internal incidence angle at the metal interface parameterized by the prism base angle. The effect of prism geometry is systematically investigated using numerical simulations under practical conditions, including a 670 nm excitation source and widely used reported optical constants for gold. A comparative analysis of triangular and hemispherical prisms across different refractive indices and base angles reveals that a 90° triangular prism can maintain a hemispherical‐like dynamic measurement range while providing ~63% higher angular sensitivity. In addition, the planar geometry enables direct metal deposition without index‐matching oils and supports modular or potentially disposable sensor architectures. These results demonstrate that optimization of the prism geometry provides an effective route to overcoming the sensitivity‐dynamic‐range limitations of conventional angular SPR configurations and establishes a quantitative design guideline for improved SPR sensor performance.
Kim et al. (Thu,) studied this question.