A　wave-meter　based　on　Michelson　interferometer　consists　of　a　reference　and　a　measurement　channel.　The　voice-coiled　motor　using　PID　means　can　realize　to　move　in　stable　motion.　The　wavelength　of　a　measurement　laser　can　be　obtained　by　counting　interference　fringes　of　reference　and　measurement　laser.　Reference　laser　with　frequency　stabilization　creates　a　cosine　interferogram　signal　whose　frequency　is　proportional　to　velocity　of　the　moving　motor.　The　interferogram　of　the　reference　laser　is　converted　to　pulse　signal,　and　it　is　subdivided　into　16　times.　In　order　to　get　optical　spectrum,　the　analog　signal　of　measurement　channel　should　be　collected.　The　Analog-to-Digital　Converter　(ADC)　for　measurement　channel　is　triggered　by　the　16-times　pulse　signal　of　reference　laser.　So　the　sampling　rate　is　constant　only　depending　on　frequency　of　reference　laser　and　irrelative　to　the　motor　velocity.　This　means　the　sampling　rate　of　measurement　channel　signals　is　on　a　uniform　time-scale.　The　optical　spectrum　of　measurement　channel　can　be　processed　with　Fast　Fourier　Transform　(FFT)　method　by　DSP　and　displayed　on　LCD.