Image pickup device and method

An image pickup device, comprising:

• an observation target holding unit that holds an observation target;
• a detection unit in which detection elements for detecting light emitted from the observation target are arranged in a two-dimensional manner;
• a lens unit which is disposed between the observation target holding unit and the detection unit and in which a plurality of lens arrays, each of which includes a plurality of refractive index distribution type lenses that are linearly arranged, are arranged in a direction perpendicular to an arrangement direction of the refractive index distribution type lenses and a lens holding unit that blocks the light is provided between the lens arrays;
• a moving mechanism that moves the lens unit or the observation target holding unit and the detection unit in the perpendicular direction;
• and
• a moving mechanism control unit that controls the moving mechanism,
• wherein the moving mechanism control unit controls the moving mechanism such that the lens unit or the observation target holding unit and the detection unit are moved to a second position from a first position, and
• the second position is a position when the lens array of the lens unit after the movement is disposed at a position facing a detection surface of the detection unit shielded by the lens holding unit when the lens unit is disposed at the first position.