An　optical　spectrometer　based　on　the　Fourier　transform　is　presented.　Both　the　measured　light　and　reference　light　are　illuminated　into　a　Michelson　interferometer　with　angle　difference　between　two　mirrors,　and　the　Fourier　transform　spectra　of　the　interference　fringes　are　obtained　by　using　charge-coupled　device　(CCD)　and　the　field-programmable　gate　array　(FPGA).　The　peak　point　in　the　Fourier　transform　spectra　of　the　reference　light　is　used　to　calibrate　the　measured　light,　and　the　wavelength　of　the　measured　light　can　be　detected　by　calculating　the　Fourier　transform　spectra　between　the　measured　light　and　the　reference　light.　Due　to　the　Michelson　interferometer　with　angle　difference　between　two　mirrors,　the　Fourier　transform　spectrometer　is　realized　without　any　mechanical　movement,　and　the　accuracy　of　the　optical　spectrometer　is　improved　by　propagating　two　lights　into　the　common　optical　path　in　the　same　Michelson　interferometer.　The　experiment　shows　that　the　maximum　error　is　1.15　nm.　The　proposed　method　possesses　high　performance,　high　reliability,　and　low　cost.　(C)　2015　Elsevier　GmbH.　All　rights　reserved.