Stereoscopic microscope with high numerical aperture
View Patent ↗A telescope-type stereomicroscope which is outfitted with an objective and two magnification changers arranged downstream of the objective. In this telescope-type stereomicroscope, the light from an object that is being examined enters the objective. Two light bundles of the light re-exiting from the objective, which are oriented parallel to one another, enter the magnification changers. The optical axes of the magnification changers are arranged at a fixed distance from one another. Each magnification changer has an entrance pupil for the light bundle associated with it. The entrance pupil has a diameter D EP that depends on the respective selected magnification, where the condition D EP >B/1.06 is met at the maximum selected magnification. Optionally, the stereomicroscope meets the condition tan(ω)≧0.16 with respect to the angle ω at which the light coming from an extra-axial point P at the object enters the magnification changers at the lowest possible magnification setting.
1. A telescope-type stereomicroscope comprising:
an objective;
two magnification changers which are arranged downstream of the objective for selecting different magnifications while observing an object;
light coming from an object entering the objective;
two light bundles of the light re-exiting from the objective which are oriented parallel to one another entering said magnification changers;
optical axes of the magnification changers being arranged at a fixed distance B from one another;
each magnification changer having an entrance pupil for the light bundle associated with it, which entrance pupil has a diameter D EP that depends on the respective selected magnification; and
condition D EP >B/1.06 being met at the maximum selected magnification.
2. The stereomicroscope according to claim 1 ,
wherein the condition B/1.06<D EP ≦B/1.04 is met, and the two magnification changers are constructed in such away that their physical extension perpendicular to the optical axes in direction of the respective neighboring magnification changer is ≦B/2.
3. The stereomicroscope according to claim 1 ;
wherein the condition D EP ≦1.55★B is met.
4. The stereomicroscope according to claim 3 ;
wherein the diameter D EP =23 mm and the distance B≧14.8 mm.
5. The stereomicroscope according to claim 1 ;
wherein the angle ω at which the light coming from an extra-axial point P at the object enters the magnification changers and which depends on the selected magnification meets the condition tan(ω)≧0.16 at the lowest possible magnification setting.
6. The stereomicroscope according to claim 1 ;
wherein said magnification changers comprise at least four optical assemblies, two of which being displaceable relative to one another and relative to the rest of the assemblies when changing magnification.
7. The stereomicroscope according to claim 6 ;
wherein every selectable magnification can be achieved by an identically directed displacing movement of the two movable assemblies, wherein the relative distance between the two assemblies changes during the displacing movement.
8. The stereomicroscope according to claim 7 ;
wherein said magnification changers having the following constructional data:
Abbe
Plane or
Thick-
Variable
Refractive
Number
lens group
Radii r
nesses d
distances
Index n e
ν e
Ø EP
Infinity
space to
the
objective
LG1
55.83000
4.50000
1.530190
76.58
23
−55.83000
2.30000
1.584820
40.57
infinity
a1
LG2
−35.22750
1.40000
1.747910
44.57
10.2
9.17300
2.50000
1.812659
25.16
25.12050
a2
LG3
30.06750
1.50000
1.812659
25.16
11.6
15.07000
1.80000
1.489140
70.23
18.96900
2.90000
1.716160
53.61
−44.98960
Dia-
1.00000
phragm
infinity
10.6
a3
LG4
−47.65660
1.30000
1.620680
49.54
9.8
7.94400
2.90000
1.624080
36.11
41.86920
a4
Infinity
space to
the tube
lens
wherein selected magnifications are associated with the following distance settings:
Magnification
4.0x
1.0x
0.32x
a1
68.657
39.472
2.098
a2
11.189
40.373
77.747
a3
28.039
12.818
3.104
a4
0.016
15.237
24.951