Idograph or Eidograph: How To spell?

The word Idograph is misspelled against Eidograph, a noun meaning "An instrument for copying drawings on the same or a different scale; a form of the pantograph."

Word begins with consecutive vowels 'EI' followed by alphabets 'dograph' is misspelled as 'I' as letter 'E' is phonetically igno
Wrong Spelling:  i-dograph 
Correct Spelling:  ei-dograph 
Find more incorrect spellings of Eidograph to spell right way.