Task: Explanation
Input (English): In optics, an Abbe prism, named for its inventor, the German physicist Ernst Abbe, is a type of "constant deviation dispersive prism" similar to a Pellin–Broca prism. Question: In what year was the inventor of the Abbe prism born? Answer: 1840
Output (English): In optics, an Abbe prism, named for its inventor, the German physicist Ernst Abbe, is a type of constant deviation dispersive prism similar to a Pellin–Broca prism.