A tilt meter includes a housing structure defining an inner chamber sealed from an environment outside the housing structure. First and second optical fiber sections are provided in the inner chamber. The second optical fiber section is optically coupled to the first optical fiber section, with the second optical fiber section rotated azimuthally with respect to the first optical fiber section. The first and second optical fiber sections are arranged to receive light transmitted from a remote light source, and a tilt of the housing structure induces a differential pressure within the inner chamber to be detected by the first and second optical fiber sections.