Incubator

An incubator for culturing samples on culture containers inside a chamber adjusted to predetermined ambient conditions, comprising in the chamber:

• a plurality of stackers capable of accommodating a plurality of culture containers;
• a stacker holder removably holding the plurality of stackers;
• culture container transporter having a motor as a driving source for moving one of the culture containers into or out of the stacker;
• and
• a microscopic observer housed in a shield case with a closed construction for microscopic observation of the culture samples on culture containers through an observation window disposed on the shield case,
• wherein the shield case has a contour wherein the shield case can be disposed on the stacker holder in place of the one or a plurality of stackers, and
• when a sample on a desired culture container of the plurality of the culture containers accommodated in the stacker is microscopic observed by the microscopic observer, the culture container transporter moves the culture container out of the stacker to a position opposed to the observation window disposed on the shield case.