Abstract: A device for compensating for changes of a center wavelength of a fiber optic grating due to temperature variations comprising a holder including a first and second connector for securing a fiber optic grating, the first connector is fixed, the second connector is movable to increase or decrease a strain in the grating, a source of force applied to the second connector, and the source of force varies with changes in temperature, such that with and increase in temperature the second connector moves toward the first connector to decrease the strain in the fiber optic grating; and, a method for compensating for changes of a center wavelength of a fiber optic grating due to temperature variations.