Microscope objective

1. An objective, particularly for telescope-type stereomicroscopes, wherein the objective comprises two lens groups of which, considered from the object plane, a first lens group with positive refractive power is next to the object plane and a second lens group with negative refractive power is next to optics arranged downstream, wherein the following conditions are met:

46.5<D AP ≦60; and  B 1

0.16≦tan ω 1 ;  B 2

where D AP represents the diameter of the exit pupil of the objective and ω 1 represents the maximum entrance angle in the downstream optics.

2. The objective according to claim 1 ;

wherein the focal length of the objective is f′≧40 mm and ≦200 mm.

3. The objective according to claim 1 ;

wherein the illumination beam path is coupled into the exit pupil of the objective.

4. The objective according to claim 3 ;

wherein the center point of the entrance pupil of the illumination beam path and the center points of the two beam paths of the objective form an isosceles triangle inside the exit pupil of the objective, the center point of the exit pupil lying inside this triangle.

5. The objective according to claim 4 ;

wherein the following conditions are met:

0.25≦ a 1 /D AP ≦0.5;

0.25≦ a 2 /D AP ≦0.5;

0.25≦ a 3 /D AP ≦0.5;

where a 1 and a 2 are the distances of the center points of the two beam paths of the objective from the center point of the exit pupil of the objective, and a 3 is the distance of the center point of the entrance pupil of the illumination beam path from the center point of the exit pupil of the objective.

6. The objective according to claim 1 ;

wherein the focal length of this second lens group satisfies the following condition:

−0.0668* f′ 2 +7.4933* f′− 460≦ f′ 2 ≦−0.0668 f′ 2 +7.4933* f′− 400,

where f′2 is the focal length of the second lens group and f′ is the total focal length of the objective.

7. The objective according to claim 1 ;

wherein the second lens group comprises a cemented component and an individual lens, and the cemented component is arranged next to the magnification changer; and

wherein the focal length of this second lens group satisfies the following condition:

−0.0668* f′ 2 +7.4933* f′− 460≦ f′ 2 ≦−0.0668 f′ 2 +7.4933* f′− 400,

where f′2 is the focal length of the second lens group and f′ is the total focal length of the objective.

8. The objective according to claim 7 ;

wherein the cemented component of the second lens group meets the condition:

10 −8 *f′ 2 +9*10 −8 *f′− 10 −4 ≦1/ f 1 /ν e1 +1/ f 2 /ν e2 ≦10 −8 *f′ 2 +9*10 −8 *f′− 10 −4 ,

and lens ( 2 . 1 ) of this lens group meets the condition ν e3 ≦55, where f′ 1 is the focal length of the lenses ( 2 . 22 ), f′ 2 is the focal length of the lenses ( 2 . 21 ), f′ is the total focal length of the objective, ν e1 and ν e2 are the Abbe numbers of the lenses ( 2 . 22 and 2 . 21 ), and ν e3 is the Abbe number of the lens ( 2 . 1 ).

9. The objective according to claim 1 ;

wherein the first lens group has a positive refractive power and comprises a plurality of lenses of which at least two form a cemented component; and

wherein the second lens group has a negative refractive power and comprises a collecting cemented component and a dispersing lens.

10. The microscope objective according to claim 1 ;

wherein the first lens group includes lenses 1 . 1 , 1 . 2 , 1 . 3 , 1 . 4 , and 1 . 5 and the second lens group includes lenses 2 . 1 , 2 . 21 , and 2 . 22 , according to the constructional data in the following table:

Radius

Distance d

Lens

mm

mm

n e

ν e

object plane

33.23399

−143.28340

1.1

12.70000

1.498450

81.30

−45.64480

0.20000

−156.22550

1.2

10.00000

1.498450

81.30

−61.77000

0.20000

487.02500

1.3

9.00000

1.747940

44.60

86.59320

1.4

21.20000

1.498450

81.30

−86.59320

0.20000

65.55050

1.5

22.70000

1.498450

81.30

334.94300

6.71704

172.77720

2.1

9.40000

1.584820

40.56

48.69730

7.59559

193.86600

2.21

6.00000

1.607180

37.76

79.72170

2.22

8.80000

1.498450

81.30

−258.51300

where d represents the distances between the lenses, n e represents the refractive indices, and ν e represents the Abbe number of the glass; and

wherein the objective has the following performance parameters:

focal length f′=50 mm;

entrance aperture 55 mm; and

aperture ratio 1:0.9.

11. The microscope objective according claim 1 ;

wherein the first lens group includes lenses 1 . 1 , 1 . 2 , and 1 . 3 and the second lens group includes lenses 2 . 1 , 2 . 2 , and 2 . 3 , according to the constructional data in the following table:

Radius

Distance d

Lens

mm

mm

n e

ν e

object plane

81.08262

109.02830

1.1

27.00000

1.498450

81.05

−45.97500

1.2

9.70000

1.758440

52.09

−133.35410

0.15000

101.08200

1.3

14.70000

1.498450

81.05

−128.62950

1.91858

120.58530

2.1

8.70000

1.616640

44.27

45.64480

11.20295

152.25440

2.21

7.80000

1.518720

63.96

41.86920

2.22

14.00000

1.622470

63.19

613.12200

where d represents the distances between the lenses in mm, n e represents the refractive indices, and ν e represents the Abbe number of the glass; and

wherein the objective having the following performance parameters:

focal length f′=100 mm;

entrance aperture 55 mm; and

aperture ratio 1:1.8.

12. The microscope objective according claim 1 ;

wherein the first lens group includes lenses 1 . 1 , 1 . 2 , 1 . 3 , 1 . 4 , and 1 . 5 and the second lens group includes lenses 2 . 1 , 2 . 21 , and 2 . 22 , according to the constructional data in the following table:

Radius

Distance d

Lens

mm

mm

n e

ν e

object plane

61.00000

330.28404

1.1

11.10000

1.530190

67.58

−87.89693

0.15000

179.10180

1.2

13.50000

1.530190

67.58

−81.26925

2.04381

−76.62790

1.3

7.00000

1.758440

52.10

56.32682

1.4

18.70000

1.487940

80.07

−160.14134

0.15000

78.20610

1.5

17.40000

1.530190

67.58

−121.89972

0.15000

82.85538

2.1

7.0000

1.758440

52.10

49.22050

10.76007

214.01477

2.21

7.0000

1.510450

60.98

65.99372

2.22

7.65175

1.622860

60.08

276.92831

where d represents the distances between the lenses in mm, n e represents the refractive indices, and ν e represents the Abbe number of the glass;

wherein the objective having the following performance parameters:

focal length f′=80 mm;

entrance aperture 55 mm; and

aperture ratio 1:1.45.

13. The microscope objective according claim 1 ;

wherein the first lens group includes lenses 1 . 1 , 1 . 2 , 1 . 3 , and 1 . 4 and the second lens group includes lenses 2 . 1 , 2 . 2 , and 2 . 3 , according to the constructional data in the following table:

Radius

Distance d

Lens

mm

mm

n e

ν e

object plane

49.60000

−378.759

1.1

15.00000

1.4980

81.1

−46.980

0.21000

135.296

1.2

20.50000

1.440

94.6

−46.308

1.3

4.50000

1.716

53.6

−415.764

0.20000

71.814

1.4

17.90000

1.440

94.6

−254.821

1.77000

89.771

2.1

14.40000

1.489

70.2

48.347

8.20000

237.162

2.2

4.50000

1.716

53.6

68.294

2.3

12.20000

1.498

81.1

−125.885

0.40000

where d represents the distances between the lenses in mm, n e represents the refractive indices, and ν e represents the Abbe number of the glass; and

wherein the objective having the following performance parameters:

focal length f′=65.59 mm;

entrance aperture 53.5 mm; and

aperture ratio 1:1.23.

14. The objective according to claim 1 , comprising its application in fluorescence stereomicroscopes.

15. An objective, particularly in fluorescence stereomicroscopes, having the condition:

τ(350;5) j ≧0.8;

where τ(350; 5) j is the internal transmission at a wavelength of the light of 350 nm and a substrate thickness of 5 mm, and an index j=1, 2, . . . stands for all optical media of the objective.