Heinrich Erfle (April 1, 1884, Dürkheim – April 8, 1923, Jena) was a German optician who spent most of his career at Carl Zeiss. In 1917 he invented the first wide-field eyepieces for telescopes and binoculars. During his short life he developed a number of new designs for telescopes and eyepieces.[1] Erfle died at the age of 39 from an infection after he "accidentally stabbed himself in the leg with a fountain pen and did not pay attention to the wound."[2] After Erfle's death, his patent applications were filed by Rudolph Straubel for the benefit of Erfle's family.[2]