An optical cavity of volume 2 cm has central frequency v= 1018 and can support 103 modes of vibration, the wavelength range admissible for the cavity is 310-0 m to (3+(1.610))10- O 310-0 m to (3+(1.610))10- m 3x10-2 m to (3+(1.610-10))x10-2 m 310- m to (3+(1.610))10- m