Hi Mr. Ahmad,
for exp in temp= -25 and without strain, shift wavelength is 1544.293163 and reference wavelength(Bragg(central) wavelength) is 1545 nm.
and for strain sensor temp is 25 and strain is 0.0002, shift wavelength is 1548.241488 and reference wavelength(Bragg(central) wavelength) is 1548 nm.
how can I calculate that ERROR?? pls, explain thanks.