Which microscope did anton van leeuwenhoek use to observe single-celled organisms?

Question: Which microscope did anton van leeuwenhoek use to observe single-celled organisms?

In 1600s a scientist Antonie Phillips Van Leeuwenhoek used single lens microscope to examine the bacteria and protozoa. Single lens microscope also known as simple microscope. But this microscope have some disadvantage like this microscope have low resolution power because of which picture is blurry in nature and this microscope can't use in darker area/ side.