Assertion: eyepiece | /r/HasProperty | designed
Facets:
Source sentences:
text: This eyepiece has two sets of doublets and the design wasn't really 'known' until about 1890, almost 30 years after it was first designed.
text: These eyepieces are so designed that they correct the chromatic difference of magnification inherent in this type of objective.
text: These eyepieces are so designed that they correct the chromatic difference of magnification inherent in this type of objective.
text: The eyepiece is designed so that the image formed by the telescope should be formed on the flat surface of the field lens, which does have the problem that any dust on that lens will be clearly visible rather than out of focus when using the telescope.