This paper shows the method of fabrication of a microlens array comprised of a Nipkow disk used in a large-area, high-speed confocal microscopy. A Nipkow disk has two components, a microlens array disk and a pinhole array disk. The microlens array focuses illumination light onto the pinhole array disk and redirects reflected light from a surface to a sensor. The microlens which are positioned in order on a disk have a hemispheric shape with a few tens of micron in diameter, and can be fabricated by a variety of methods like mechanical machining, semiconductor process, replication process like imprinting process. This paper shows how to fabricate the microlens array which has a long focal length by reflow and imprinting process.