4. Two mirrors with the same power reflectivity R are utilized to form a Fabry-Perot resonator. If the separation of the two mirrors is L and the refractive index inside the resonator is n, what is the Free Spectral Range Af of the resonator in the frequency (not the angular frequency Aw) domain? Here the Free Spectral Range (FSR) is the optical frequency spacing between two successive reflected/transmit - ted optical intensity maxima/minima of a resonator.

4. Two mirrors with the same power reflectivity R are utilized to form a Fabry-Perot resonator. If the separation of the two mirrors is L and the refractive index inside the resonator is n, what is the Free Spectral Range Af of the resonator in the frequency (not the angular frequency Aw) domain? Here the Free Spectral Range (FSR) is the optical frequency spacing between two successive reflected/transmit - ted optical intensity maxima/minima of a resonator.