This is a correct answer to the following question about Zacharias Janssen. Yes or no?
Answer: Zacharias Janssen (also Zacharias Jansen or Sacharias Jansen) (b.1580-88, d.pre-1632 to 1638) was a Dutch spectacle-maker from Middelburg associated with the invention of the first optical telescope .
Question: when did zacharias janssen make a discovery related to the cell theory
