Fiber grating demodulation system improving spectrum resolution of detector array

The invention provides a fiber grating demodulation system improving the spectrum resolution of a detector array. The demodulation system comprises a pumping source, a wavelength division multiplexing device, a Bragg fiber grating, a diaphragm, a slit, a collimating mirror, a light splitting grating, an imaging lens, a linear array detector, a piezoelectric execution element and a voltage control system, wherein the pumping source, the wavelength division multiplexing device and the Bragg fiber grating are connected in sequence, the wavelength division multiplexing device is simultaneously connected with the diaphragm, light emitted by the pumping source enters the Bragg fiber grating after the coupling of the wavelength division multiplexing device, a reflection spectrum of the Bragg fiber grating serves as injection light and enters the fiber grating demodulation system, and after the injection light passes through the slit, the injection light is reflected by the collimating mirror, the light splitting grating and the imaging lens in sequence and is finally gathered to the linear array detector. The slit or the linear array detector is capable of moving left and right along a long axis for a small distance, and the collimating mirror, the light splitting grating and the imaging lens are capable of rotating anticlockwise or clockwise by a small angle.