Patent ID: 6628383
Filing Date: 2003-09-30
Classification: G01J

Abstract:
A cross-dispersed low-blaze-angle multiorder plane grating spectrograph using a modified Ebert-type mounting comprisinga single concave paraboloidal mirror having a focus, the mirror replacing the single spherical primary mirror of the Ebert-type mounting; a plane diffraction grating, the grating having equally-spaced grooves, the grating located near the focus of the paraboloidal mirror, the grating having a blaze angle, the blaze angle less than 20Â°; a cross-dispersing element, the cross-dispersing element located between the paraboloidal mirror and the grating; a detector array, the array containing pixels in a multiplicity of rows and a multiplicity of columns, wherein a cross-dispersed spectral image is located at the array, the spectral image containing a multiplicity of spectral orders, the orders separated from each other by the cross-dispersing element.