  Photon spheres are the characteristic of general black holes, thus are a
suitable touchstone for the emergence of gravitational spacetime in the AdS/CFT
correspondence. We provide a spectral analysis of an AdS Schwarzschild black
hole near its photon sphere. We find that quasinormal modes near the photon
sphere reflect the AdS boundary, resulting in a peculiar spectral pattern. Our
large angular momentum analysis owes to an analogue to solvable Schr\"odinger
equations such as an inverted harmonic oscillator and the P\"oschl-Teller
model, with a Dirichlet boundary condition. Through the AdS/CFT dictionary, it
predicts the existence of a peculiar subsector in the large angular momentum
spectrum of thermal holographic CFTs on a sphere.
