question: In what year was the inventor of the Abbe prism born?
answer: 1840
context: Title: Pellin–Broca prism
  Passage: A Pellin–Broca prism is a type of constant-deviation dispersive prism similar to an Abbe prism.
  Title: Porro–Abbe prism
  Passage: A Porro–Abbe prism (sometimes called a Abbe–Porro prism), named for Ignazio Porro and Ernst Abbe, is a type of reflection prism used in some optical instruments to alter the orientation of an image.  It is a variant of the more common double Porro prism configuration.
  Title: Ernst Abbe
  Passage: Ernst Karl Abbe HonFRMS (23 January 1840 – 14 January 1905) was a German physicist, optical scientist, entrepreneur, and social reformer.  Together with Otto Schott and Carl Zeiss, he laid the foundation of modern optics.  Abbe developed numerous optical instruments.  He was a co-owner of Carl Zeiss AG, a German manufacturer of research microscopes, astronomical telescopes, planetariums and other optical systems.
  Title: Abbe prism
  Passage: 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.
  Title: Emily Kai Bock
  Passage: Emily Kai Bock (born 1983 or 1984) is a Canadian writer and director.  She has directed music videos for Arcade Fire, Lorde, Grizzly Bear, and Grimes.  She won the 2014 Prism Prize for her video for the Arcade Fire song Afterlife and was nominated for Director of the Year at the 2014 Much Music Video Awards.  Her film "A Funeral for Lightning" was included in the list of "Canada's Top Ten" shorts of 2016, selected by a panel of filmmakers and industry professionals organized by TIFF.
citations: Ernst Abbe Abbe prism