We present the development of a spectral dispersion device for wideband spectroscopy for which the primary scientic objective is the characterization of transiting exoplanets. The principle of the disperser is simple: a grating is fabricated on the surface of a prism. The direction of the spectral dispersion power of the prism is crossed with the grating. Thus, the prism separates the spectrum into individual orders while the grating produces a spectrum for each order. In this work, ZnS was selected as the material for the cross disperser, which was designed to cover the wavelength region, ⋋ = 0.6-13 μm, with a spectral resolving power, R ≥ 50. A disperser was fabricated, and an evaluation of its surface was conducted. Two spectrometer designs, one adopting ZnS (⋋ = 0.6-13 μm, R ≥ 300) and the other adopting CdZnTe (⋋ = 1-23 μm, R ≥ 250), are presented. The spectrometers, each of which has no moving mechanical parts, consist simply of a disperser, a focusing mirror, and a detector.

ABSTRACT
1. SCIENCE OBJECTIVE
2. FABRICATION AND TESTS
3. DISCUSSION
REFERENCES

• Keigo Enya(Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency)
• Naofumi Fujishiro(Koyama Astronomical Observatory, Kyoto Sangyo University/LLP Kyoto NijiKoubou, Iwakura-Minamiosagi)