Lower order blaze grating spectrometer of large diffraction angle

A new kind of large dispersion lower order blaze grating spectrometer is built. The design is based on the use of uncustomary large angles of incidence and diffraction approaching 80°. The double diffraction optical scheme is employed to fit the design conception. A set of compact size grating spectrometers of various focal lengths and grating ruled widths has been manufactured and explored. The measured grating efficiency related to different blaze angles shows the evidence for the instrument gainful operation. The spectrometer imaging properties are much promising to enable a fine spectral resolution to 0.005 nm under a short focal length ∼100 mm. The estimation of flux luminosity is made in comparison with Fabry–Perot interferometer.