External laser light introducing device

1. An external laser light introducing device for introducing laser light through a beam expander comprising a movable lens from outside of an optical apparatus into inside the optical apparatus through a galvanomirror located inside the optical apparatus so that the laser light is condensed on a target by a condenser lens located inside the optical apparatus, wherein the external laser light introducing device comprises:

a pupil projection optical system consisting of a pair of fixed lenses for projecting an external pupil of the beam expander on the galvanomirror; and

an optical axis aligning mechanism for aligning an axis of a beam of the laser light with an optical axis of the external pupil,

wherein the external pupil is located where the position and/or a diameter of the beam of the laser light is unchanged by the optical axis alignment mechanism.

2. The external laser light introducing device according to claim 1 , wherein the optical axis aligning mechanism includes:

an optical axis position adjusting mechanism for making a position of the axis of the beam of the laser light practically coincide with a center of the external pupil; and

an optical axis angle adjusting mechanism for making an angle of the optical axis of the external pupil practically coincide with any angle of the axis of the beam of the laser light after the position of the axis of the beam of the laser light is made to practically coincide with the center of the external pupil by the optical axis position adjusting mechanism.

3. The external laser light introducing device according to claim 1 , further comprising wavefront curvature adjusting mechanism for adjusting a wavefront curvature of the beam of the laser light at the external pupil.

4. An external laser light introducing device for introducing a plurality of beams of laser light through a beam expander comprising a movable lens from outside of an optical apparatus into inside the optical apparatus through a galvanomirror located inside the optical apparatus, such that the laser light is condensed on a target by a condenser lens located inside the optical apparatus, wherein the external laser light introducing device comprises;

a pupil projection optical system consisting of a pair of fixed lenses for projecting an entrance pupil of the condenser lens on an external pupil located outside the optical apparatus;

a plurality of optical axis aligning mechanisms for aligning axes of the plurality of beams of laser light, respectively, with an optical axis of the external pupil, the external pupil being located where at least one of a position and a diameter of each of the beams of laser light is unchanged by the optical axis alignment mechanisms; and

a plurality of wavefront curvature adjusting mechanisms for adjusting wavefront curvatures of the plurality of beams of laser light at the external pupil, respectively, the external pupil being located where at least one of a position and a diameter of each of the beams of laser light is unchanged by the wavefront curvature adjusting mechanisms.

5. The external laser light introducing device according to claim 1 , further comprising an optical axis position detector for detecting a position of incidence of the laser light at the external pupil.

6. The external laser light introducing device according to claim 5 , wherein the optical axis aligning mechanism includes an optical axis position adjusting mechanism for making a position of the axis of the beam of the laser light practically coincide with a center of the external pupil, and the external laser light introducing device further comprises an optical axis position feedback device that drives the optical axis position adjusting mechanism by using an output from the optical axis position detector.

7. The external laser light introducing device according to claim 1 , further comprising an optical axis angle detector for detecting an angle of incidence of the laser light at the external pupil.

8. The external laser light introducing device according to claim 7 , wherein the optical axis aligning mechanism includes an optical axis angle adjusting mechanism for making an angle of the optical axis of the external pupil practically coincide with an angle of the axis of the beam of the laser light, and the external laser light introducing device further comprises an optical axis angle feedback device that drives the optical axis angle adjusting mechanism by using an output from the optical axis angle detector.

9. An external laser light introducing device for introducing laser light through a beam expander comprising a movable lens from outside of an optical apparatus into inside the optical apparatus through a galvanomirror located inside the optical apparatus, such that the laser light is condensed on a target by a condenser lens located inside the optical apparatus, wherein the external laser light introducing device comprises:

a pupil projection optical system consisting of a pair of fixed lenses for projecting an external pupil of the beam expander on the galvanomirror; and

a wavefront curvature adjusting mechanism for adjusting wavefront curvature of a beam of the laser light at the external pupil, the external pupil being located where at least one of a position and a diameter of the beam of the laser light is unchanged by the wavefront curvature adjusting mechanism.

10. A method of introducing external laser light through a beam expander comprising a movable lens from outside of an optical apparatus into inside the optical apparatus through a galvanomirror located inside the optical apparatus, such that the laser light is condensed on a target by a condenser lens located inside the optical apparatus, wherein the method comprises:

projecting an entrance pupil of the condenser lens via a pair of fixed lenses on an external pupil located outside the optical apparatus; and

adjusting a wavefront curvature of a beam of the laser light at the external pupil using wavefront curvature adjusting mechanism, the external pupil being located where at least one of a position and a diameter of the beam of the laser light is unchanged by the wavefront curvature adjusting mechanism.

11. A laser microscope apparatus comprising:

a laser light source section emitting laser light;

a microscope body including an objective lens for magnifying and observing a specimen; and

an external laser light introducing device for introducing the laser light into the microscope body through a beam expander comprising a movable lens;

wherein the external laser light introducing device includes a pupil projection optical system consisting of a pair of fixed lenses for projecting an entrance pupil of the objective lens on an external pupil of the microscope body and a wavefront curvature adjusting mechanism for adjusting a wavefront curvature of a beam of the laser light at the external pupil, the external pupil being located where at least one of a position and a diameter of the beam of the laser light is unchanged by the wavefront curvature adjusting mechanism.

12. The external laser light introducing device according to claim 1 , further comprising:

at least one another optical axis aligning mechanism so that the external laser light introducing device has a plurality of optical axis aligning mechanisms for practically aligning axes of a plurality of beams of the laser light, respectively, with the optical axis of the external pupil; and

a beam combiner for combining the plurality of beams of the laser light to introduce the laser light as combined into the entrance pupil.