The article "Observation of trapped light within the radiation continuum" by Hsu et al. (2013) presents a novel method to confine light in a dielectric slab, even when outgoing waves are allowed in the surrounding medium. This phenomenon, known as an "embedded eigenvalue," is not due to symmetry incompatibility but rather to destructive interference between multiple leakage channels. The authors use a photonic crystal (PhC) slab with a square array of cylindrical holes to demonstrate this effect. They show that at specific points in the Brillouin zone, the lifetime of the guided resonance becomes infinite, leading to perfect light confinement. This trapped state has a high quality factor, large area, and strong confinement near the surface, making it potentially useful for various applications such as chemical/biological sensing, organic light-emitting devices, and large-area laser applications. The study also confirms the existence of this trapped state through experimental measurements and numerical simulations, providing a robust and versatile approach to wave localization.The article "Observation of trapped light within the radiation continuum" by Hsu et al. (2013) presents a novel method to confine light in a dielectric slab, even when outgoing waves are allowed in the surrounding medium. This phenomenon, known as an "embedded eigenvalue," is not due to symmetry incompatibility but rather to destructive interference between multiple leakage channels. The authors use a photonic crystal (PhC) slab with a square array of cylindrical holes to demonstrate this effect. They show that at specific points in the Brillouin zone, the lifetime of the guided resonance becomes infinite, leading to perfect light confinement. This trapped state has a high quality factor, large area, and strong confinement near the surface, making it potentially useful for various applications such as chemical/biological sensing, organic light-emitting devices, and large-area laser applications. The study also confirms the existence of this trapped state through experimental measurements and numerical simulations, providing a robust and versatile approach to wave localization.