Scanning microscope unit, scanning microscope, and calibration method for scanning microscope unit

A scanning microscope unit to be attached to a connection port of a microscope including a microscope optical system to form a scanning microscope, the unit comprising:

• a light source configured to output irradiation light;
• a photodetector configured to detect observation light generated from an observation object in response to irradiation with the irradiation light;
• a MEMS mirror configured to scan the irradiation light output from the light source, over the observation object, and for guiding the observation light generated from the observation object in response to the irradiation with the irradiation light, toward the photodetector;
• a scanning lens configured to guide the irradiation light scanned by the MEMS mirror, to the microscope optical system, and configured to guide the observation light imaged by the microscope optical system, to the MEMS mirror;
• and
• a frame member formed in a frame shape to define an opening, and disposed on a side of the microscope optical system with respect to the scanning lens such that the irradiation light and the observation light pass through the opening, the frame member including a calibration portion provided in a side portion defining the opening, and configured to generate calibration light including a sensitivity wavelength of the photodetector in response to an incidence of the irradiation light,
• wherein the frame member includes a plate member configured to generate the calibration light in response to the incidence of the irradiation light, and a covering member disposed on the plate member to cover the plate member, and
• the calibration portion is formed of a part of the plate member exposed from an exposure opening formed in the covering member.