Micro-grating design and process is depicted based the experience of author several years ago.Spectral analysis instruments (or spectrometers) for the detection and identification of materials and compounds are very practical and common. General spectrum analysis instruments (or spectrometers) are not only bulky but also very expensive. Therefore, if there is a small size and it is easy to carry and use, it will be very practical in many occasions, such as the immediate inspection of production lines or places such as seaside and mountains.Micro-gratings can be applied to spectral analysis. The technology has the advantages of non-destructive, non-invasive, high sensitivity, high chemical discrimination rate and fast speed in data analysis.By miniaturizing and mass-producing the spectral analysis instrument through the micro-nano system process technology, it can be as a common monitor for the production process, ecological environment and biochemical medical information in real time, providing high efficiency and safe and stable quality of people life.Spectral analysis instruments (or spectrometers) are usually used in the wavelength range of ultraviolet (UV), visible (NIR/near inferred), infrared (IR), and short-wave infrared (SWIR/short wave IR).