Pressure sensor

A pressure sensor comprising:

• an optical fiber strain sensor;
• an optical fiber strain sensor carrier means having a sensing region in which the optical fiber strain sensor is provided, the carrier means comprising a first material having a first stiffness in the direction of strain sensing;
• and
• pressure modifying means comprising a second material having a second stiffness in the direction of strain sensing, the pressure modifying means being mechanically coupled to the optical fiber strain sensor carrier means within the sensing region, such that when the pressure sensor is exposed to pressure, compression produced within the pressure modifying means acts on the optical fiber strain sensor carrier means, and thereby modifies the compression in the direction of strain sensing produced within the sensing region due to the applied pressure
• wherein the pressure modifying means comprises a first orthotropic material, having a low elastic modulus in the direction of strain and a higher elastic modulus in the perpendicular plane to the direction of strain.