IdealPhotonics' newly launched optical reference cavity is a precision optical device based on a high-precision resonant cavity (such as a Fabry-Perot structure). It provides sub-Hertz-level linewidth laser frequency locking through an ultra-stable frequency reference (such as atomic/molecular transitions or crystal oscillations).Achieving sub-Hertz-level laser frequency stabilization using an ultra-low-loss resonant cavity and ultra-stable materials relies heavily on ultra-high reflectivity mirrors, thermal/vibrational isolation technology, and an active frequency stabilization system, providing a reference frequency for optical clocks and precision measurements.