Arrangement for high-resolution spectroscopy

#1. Field of the Invention

#The present invention is directed generally to an arrangement for high-resolution spectroscopy including a wavelength selective diode array having different spectral sensitivities.

#2. Description of the Related Art

#FIG. 1 is a perspective view showing an arrangement for high resolution spectroscopy including a wavelength selective diode array and a wedge shaped interference filter in accordance with the principles of the present invention;

#FIG. 2 is a graph showing the sensitivity of individual elements of a diode array as a function of wavelength;

#FIG. 3a is a graph showing, in greater detail, the wavelength sensitivity of diode elements;

#In an arrangement according to the present invention as shown in FIG. 1, a wedge-shaped interference filter 11 is included which is composed of a material transmissive for light to be investigated. A first diode array 12 is aligned with the interference filter 11 as shown by the broken lines. The diode array 12 is constructed on a first substrate 121 over which is applied a first layer structure 122. The first diode array 12 is composed of a semiconductor material. The band spacing of the semiconductor material steadily decreases in the direction perpendicular to the first layer structure 122 proceeding from the first substrate 121 for wavelength selectivity. The band spacing is greatest in the first substrate 121; and it is smallest at the end of the first layer structure 122 facing away from the first substrate 121.

#A surface 125 of the first layer structure 122 that faces away from the first substrate 121 is beveled, or angled, and a plurality of first contacts 123 are applied to this beveled surface 125. The first contacts 123 are arranged in a two dimensional field which is laid out along the direction of the slope of the beveled surface and the direction perpendicular to the direction of the slope and parallel to the beveled surface.

#The band spacing steadily changes in the direction of the slope of the beveled surface, so that two respective neighboring contacts see a different band spacing in this direction.