Spectrometer is the scientific instrument that is the photolysis with complex part spectral line, wait by prism or diffractive grating form, appearance of benefit consumed chart is measurable light of object surface catoptric. The 7 shade in sunshine are the share that naked eye can distribute (visible light) , dan Retong crosses spectrometer to decompose sunshine, arrange by wavelengh, visible light takes the very little scope in spectrum only, the others is the spectrum that naked eye cannot differentiate, if ray of infrared ray, microwave, ultraviolet ray, X is waited a moment.

Be opposite through spectrometer the capture of smooth information, in order to take a picture negative develop, or computerization shows numerical value automatically to the instrument shows and be analysed, measure thereby in knowing article, contain why to plant element. This kind of technology is applied at industry of sanitation of air pollution, water pollution, food, metal to wait widely in detecting. Will answer shade depart becomes spectral telescope.

Spectrometer has a variety of kinds, outside dividing the spectrometer that uses in visible light wave band, still have infra-red spectrometer and appearance of ultraviolet light chart. Those who press chromatic dispersion component is different can divide wait for prism spectrometer, grating spectrometer and interference spectrometer. Press exploration method cent, have the spectroscope of the direct observation that use an eye, with the spectrograph that plate records, and the spectrophotometer that explores spectrum with photoelectricity or thermoelement.

Monochromator is the spectral instrument that outputs monochromatic spectral line only through slit, often cooperate to use with other analysis instrument. The parameter with token basic and characteristic spectrometer has rate of spectral limits, chromatic dispersion, bandwidth and resolving power to wait. The spectrometer that is based on interference principle design has very high chromatic dispersion rate and resolving power, commonly used Yu Guangpu is careful structural analysis.

Spectrometer is the basic structure of prism spectrograph. Of slit S and prism advocate sectional and perpendicular, set the thing in lenticular L inside square scorched area, plate is placed in lenticular L like square scorched area inside. With S of illuminant illume slit, of S resemble making spectral line on plate, as a result of the chromatic dispersion action of prism, the spectral line of different wavelengh each other are apart, have to the spectrum of incident light. The spectral limits decision that prism spectrograph can observe is opposite at the optical component such as prism absorb spectrally.

Common and optical glass applies to visible light wave band only, use quartz to be able to expand to violet outskirt, in infra-red area general use sodium chloride, bromine changes potassium and fluorine to change the crystal such as calcium. The reflexes type grating spectrometer spectral range that uses generally at present depends on the design of grating stripe, can have wider spectral range.