Microscope system

1. A microscope system comprising:

a stage on which a specimen is mounted and that can be moved in a direction that intersects with an optical axis of illumination light irradiated on the specimen;

an observation optical system that acquires an image of the specimen on which the illumination light is radiated;

a display unit that displays a first image acquired by the observation optical system;

a viewing-range setting unit that sets a viewing range of the image in the first image displayed on the display unit, and displays a second image that is a portion of the first image on the display unit;

a ratio calculating unit that calculates a ratio of the viewing range of the image, which is set by the viewing-range setting unit, relative to a maximum image-acquisition area that can be captured by the observation optical system; and

a stage controller that sets a moving speed of the stage with respect to the second image in accordance with the ratio calculated by the ratio calculating unit and a moving speed of the stage with respect to the first image.

2. A microscope system according to claim 1 , wherein the ratio calculating unit calculates at least one of a vertical scale factor and a horizontal scale factor of the viewing range of the image, which is set by the viewing-range setting unit, relative to the maximum image-acquisition area.

3. A microscope system according to claim 1 , wherein the stage controller increasingly reduces the moving speed of the stage with a reduction in the ratio calculated by the ratio calculating unit.

4. A microscope system according to claim 1 , wherein the stage controller controls the moving speed of the stage so as to make the moving speed of an observation image of the specimen relative to the viewing range of the image constant before and after the ratio calculated by the ratio calculating unit is changed.

5. A microscope system according to claim 1 , further comprising an overall-magnification calculating unit that calculates an overall magnification of the observation optical system,

wherein the stage controller controls the moving speed of the stage in accordance with the ratio calculated by the ratio calculating unit and the overall magnification calculated by the overall-magnification calculating unit.

6. A microscope system according to claim 5 , wherein

the observation optical system is provided with an objective lens that collects observation light from the specimen irradiated with the illumination light; and

the overall magnification includes a magnification of the objective lens.

7. A microscope system according to claim 1 , wherein

the observation optical system is provided with an image acquisition unit that captures observation light from the specimen irradiated with the illumination light; and

the ratio calculating unit calculates the ratio on the basis of the maximum image-acquisition area of the image acquisition unit.

8. A microscope system according to claim 1 , wherein

the viewing-range setting unit has a digital zoom function that electrically enlarges and shrinks an observation image of the specimen relative to the viewing range of the image; and

the stage controller controls the moving speed of the stage in accordance with the ratio calculated by the ratio calculating unit and a magnification of the observation image of the specimen determined by the digital zoom function of the viewing-range setting unit.

9. A microscope system according to claim 1 , further comprising:

a stage drive unit that drives the stage; and

a speed instruction unit that gives an instruction about moving speed of the stage to the stage drive unit.