The pressure sensitivity of the phase in optical fibers has been studied analytically by taking into account the exact composition and geometry of multilayer fibers. This analysis shows that there are combinations of glass and coating materials and corresponding thicknesses which make fibers pressure insensitive.
N. Lagakos and J. A. Bucaro, "Pressure desensitization of optical fibers," Appl. Opt. 20, 2716-2720 (1981)