Microstress sensing device based on prague fiber grating

The utility model relates to a microstress sensing device based on prague fiber grating belongs to optical fiber sensing technical field its structure has, broad-spectrum light source (1) links to each other through optical isolator (2) 1 port with optical coupler (3), 2 ports of optical coupler (3) pass through linking to each other of prague fiber grating FBG2 and spectrum appearance (4), index-matching fluid (5) are put into to the output optical fibre of 4 ports of optical coupler (3), the optic fibre of prague fiber grating FBG1 one end links to each other with 3 ports of optical coupler (3), the optic fibre of the other end bonds with transfer line (7) that are arranged in spacing hole (8), on base (11) that placed through left branch vaulting pole (9) and right branch vaulting pole (10) the level of being fixed in optic fibre anchor clamps (6) and spacing hole (8), the utility model discloses under the very little circumstances of FBG prague wavelength change, realize measuring with high precision small stress, measurement resolution improves hundreds of times than the conventional art