Angle‐Dependent Circular Polarization Modulation of Blue‐Phase Liquid Crystal Laser

Circularly polarized (CP) lasers are pivotal for advanced photonic information processing, yet metasurface‐based CP light manipulation suffers from complex fabrication and limited 3D chiral modulation. Blue phase liquid crystals (BPLCs), as self‐assembled 3D chiral photonic materials, hold great potential for CP lasers, but the intrinsic correlation between their lattice orientation, emission angle, and CP degree remains unstudied. Here, we fabricate a monolithic bilayer PSBP/C6 system integrating a polymer‐stabilized BPLC resonant cavity and dye‐doped gain layers, spatially decoupling chiral modulation and optical gain while ensuring lossless light propagation. This system achieves efficient dual‐handed circularly polarized luminescence (g lum = +1.22 for LCPL; g lum = −0.51 for RCPL) and a high‐performance right‐handed CP laser with a narrow linewidth (0.050 nm) and a high Q‐factor (11083). Angle‐resolved measurements along three crystallographic axes reveal a universal non‐monotonic angular dependence of CP degree, reflecting the 3D chiral optical modulation of BPLCs. We further demonstrate multi‐channel CP optical signal encoding/decoding via pump‐energy‐dependent CPL/CP laser switching and angular chiral response. This work uncovers the mechanism of angle‐dependent CP lasing in 3D chiral photonic crystals and provides a scalable design paradigm for integrated chiral photonic devices.