Light-stimulus illumination apparatus which scans light-stimulus laser light in a direction intersecting an optical axis

1. A light-stimulus illumination apparatus comprising:

a light source configured to emit light-stimulus laser light;

a scanning unit including a first acousto-optic device configured to scan the light-stimulus laser light emitted from the light source in a first direction intersecting an optical axis, and a second acousto-optic device configured to scan the light-stimulus laser light emitted from the light source in a second direction intersecting the optical axis and orthogonal to the first direction; and

a control unit configured to control the scanning unit so that the light-stimulus laser light irradiates a plurality of spatially separated regions including a first region and a second region in a time-division manner,

wherein the control unit is configured to control the scanning unit to scan the light-stimulus laser light in the second region right after finishing scanning the light-stimulus laser light in the first region by switching a frequency of each command signal input to the first and second acousto-optic devices discontinuously from a frequency corresponding to a scanning end point of the first region to a frequency corresponding to a scanning starting point of the second region so that the light-stimulus laser light does not irradiate an area between the first region and the second region.

2. A light-stimulus illumination apparatus according to claim 1 , wherein the control unit adjusts the amplitudes of the command signals input to the first and second acousto-optic devices according to a scanning position of the light-stimulus laser light scanned by the scanning unit.

3. A light-stimulus illumination apparatus according to claim 1 , further comprising:

a focal-position adjusting unit configured to change a focal position of the light-stimulus laser light in a direction of the optical axis, wherein the control unit controls the focal-position adjusting unit in synchronization with the scanning unit.

4. A light-stimulus illumination apparatus according to claim 1 , wherein the light-stimulus laser light is ultrashort pulsed laser light.

5. A light-stimulus illumination apparatus according to claim 4 , further comprising a light detector configured to detect fluorescence due to multiphoton excitation produced by irradiation with the light-stimulus laser light, without the fluorescence returning to the scanning unit.

6. A microscope apparatus comprising the light-stimulus illumination apparatus according to claim 1 .

7. A laser-scanning microscope apparatus comprising:

a light-stimulus illumination apparatus according to claim 1 ; and

a laser-scanning microscope comprising:

an observation light source configured to emit observation laser light;

an observation scanning unit configured to two-dimensionally scan the observation laser light on a specimen;

an objective lens configured to converge the observation laser light on the specimen and to collect observation light emitted from the specimen by irradiation with the observation laser light;

a detection unit configured to detect the observation light collected by the objective lens; and

an image-generating unit configured to generate an observation image of the specimen based on a detection signal from the detection unit,

wherein the light-stimulus laser light irradiates the specimen via the objective lens of the laser-scanning microscope.

8. A laser-scanning microscope apparatus according to claim 7 , further comprising:

a combining unit, between the observation scanning unit and the objective lens, configured to combine the light-stimulus laser light from the light-stimulus illumination apparatus,

wherein the light-stimulus laser light scanned by the scanning unit of the light-stimulus illumination apparatus is guided to the combining unit.