SUBSTRATE FOR AN OPTICAL FILTER AND OPTICAL FILTER

The present invention relates to an improved substrate for an optical filter and an optical filter. The substrate comprises a SiO 2, ZnO, KO and cadmium chalcogenide-containing filter glass which hasa TeO content of 0.1% to 3% by weight and a CoO content of 1.0% to 7.0% by weight, preferably 1.0% to 7.0% by weight. In this case, the filter glass has a first stopband in the visible region of the spectrum and a passband in the near IR region of the spectrum, a first transmission edge and an edge wavelength Lambda'i0.5 between 700 nm and 840 nm, based on a filter glass thickness of 0.3 mm. 本发明涉及一种用于光学滤波器的改进的基板和一种光学滤波器。基板包括滤光玻璃，该滤光玻璃含有SiO、ZnO、KO和镉的硫族化物，该滤光玻璃基于氧化物，TeO含量为0.1重量％至3重量％，CoO含量为1.0重量％至7.0重量％，优选>1.0重量％至7.0重量％。滤光玻璃具有在光谱的可见光区域中的第一阻挡范围、在光谱的近红外区域中的通带、第一透射边缘和基于0.3mm的滤光玻璃厚度在700nm和840nm之间的边缘波长λ'。