Optical arrangement and method for the imaging of depth-structured objects

1. An optical arrangement for imaging depth-structured objects comprising:

at least one afocal magnification changer;

an entrance pupil in front of the at least one afocal magnification changer;

an aperture diaphragm;

a receiver surface positioned in the imaging beam path;

at least one optical assembly which is displaceable in axial direction being provided between the aperture diaphragm and the receiver surface; and

displacement of said optical assembly within a predetermined length range causing a change in focus position while the magnification remains the same;

wherein the entrance pupil is located in a non-telecentric position; and

wherein the optical arrangement is constructed to generate images from different observation planes at different depth levels of an object.

2. The optical arrangement according to claim 1 , wherein stereo microscope carries out the generation of images from different observation planes at different depth levels of an object.

3. The optical arrangement according to claim 1 , wherein the displaceable optical assemblies are lenses or lens groups of the magnification changers.

4. The optical arrangement according to claim 3 , wherein the afocal magnification changers are for a magnification range of 12.5× and comprise, respectively, four lens groups LG 11 to LG 14 with radius r, thickness d, distance a relative to one another, refractive index ne, Abbe number ve with respect to the wavelength of 546.07 nm:

Variable

Refractive

Abbe

Plane or lens

Radius

Thickness

distance

index

number

group

r (mm)

d (mm)

(mm)

n e

ν e

Infinity space

to the

objective

LG11

55.83000

4.50000

1.530190

76.58

−55.83000

2.30000

1.584820

40.57

infinity

a1

LG12

−35.22750

1.40000

1.747910

44.57

9.17300

2.50000

1.812659

25.16

25.12050

a2

LG13

30.06750

1.50000

1.812659

25.16

15.07000

1.80000

1.489140

70.23

18.96900

2.90000

1.716160

53.61

−44.98960

1.00000

Diaphragm

infinity

a3

LG14

−47.65660

1.30000

1.620680

49.54

7.94400

2.90000

1.624080

36.11

41.86920

a4

Infinity space

to the tube

lens

with the following magnifications associated with the variable distances:

4.0×

1.0×

0.32×

a1

68.657

39.472

 2.098

a2

11.189

40.373

77.747

a3

28.039 ± 1

12.818 ± 1

 3.104 ± 1

a4

 0.016 ± 1

15.237 ± 1

24.951 ± 1

wherein lens group LG 14 is displaceable by about ±1 mm within a length range extending in axial direction without causing a change in the magnification predetermined by this magnification changer.

5. The optical arrangement according to claim 3 , with afocal magnification changers ( 5 . 1 , 5 . 2 ) with a structural length of 130 mm and a magnification range of 20×, each comprising five lens groups LG 21 to LG 25 with radius r, thickness d, distance a relative to one another, refractive index ne, Abbe number ve with respect to the wavelength of 546.07 nm:

Variable

Refractive

Abbe

Plane or lens

Radius

Thickness

distance

index

number

group

r (mm)

d (mm)

(mm)

n e

ν e

Infinity space

to the

objective

LG21

55.83000

4.50000

1.530190

76.58

−55.83000

2.30000

1.584820

40.57

infinity

a1

LG22

−29.63900

1.40000

1.747910

44.57

9.57600

2.50000

1.812659

25.16

28.59370

a2

LG13

17.66550

1.40000

1.708240

39.12

9.44240

3.15000

1.530190

76.58

−30.94640

1.00000

Diaphragm

infinity

LG24

−27.97950

2.10000

1.812659

25.16

−10.59190

1.30000

1.747910

44.57

38.12900

a4

LG25

54.24520

2.05000

1.708240

39.12

33.25480

2.28000

1.489140

70.23

infinity

Infinity space

to the tube

lens

with the following magnifications associated with the variable distances:

6.0×

2.0×

0.3×

a1

69.713

51.441

2.608

a2

2.034

20.306

69.139

a3

32.226

20.448

4.346

a4

2.047 ± 1

13.824 ± 1

29.927 ± 1

Infinity space

to the tube

lens ±1

wherein lens group LG 25 is displaceable by about ±1 mm within a length range extending in axial direction without causing a change in the magnification predetermined by this magnification changer.

6. The optical arrangement according to claim 1 , wherein afocal magnification systems are provided for a determined magnification, and the displaceable optical assemblies are lenses or lens groups of these magnification systems.

7. The optical arrangement according to claim 6 , with afocal magnification systems for a magnification of −1×, each comprising two lens groups LG 31 and LG 32 with radius r, thickness d, distance a relative to one another, refractive index ne, Abbe number ve and focal length f′ with respect to the wavelength of 546.07 nm:

Variable

Refractive

Abbe

Focal length

Radius

Thickness

distance

index

number

f′

Lens group

r (mm)

d (mm)

(mm)

n e

ν e

(mm)

Infinity space

to the

objectiv

LG31

42.98863

3.80000

1.620680

49.5

33.5

−8.19285

2.00000

1.652220

33.6

−32.45360

infinity

31.90559

29.66671 ± 0.5

LG32

136.36165

3.80000

1.582120

53.6

33.5

−9.70164

2.00000

1.723079

29.4

−18.12777

±0.5

Infinity space

to the tube

lens

wherein lens group LG 32 is displaceable relative to lens group LG 31 within a length range of about ±0.5 mm extending in axial direction without causing a change in the magnification that is predetermined by this magnification system.

8. The optical arrangement according to claim 6 , with afocal magnification systems for a magnification of 1×, each comprising two lens groups LG 41 and LG 42 with radius r, thickness d, distance a relative to one another, refractive index ne, Abbe number ve and focal length f′ with respect to the wavelength of 546.07 nm:

Variable

Refractive

Abbe

Focal

Radius

Thickness

distance

index

number

length

Lens group

r (mm)

d (mm)

(mm)

n e

ν e

(mm)

Infinity space

to the

objective

LG41

−227.78200

2.50000

1.761639

27.2

−22.9

−18.41300

1.50000

1.616640

44.3

11.78000

0.60142 ± 0.5

LG42

12.22100

1.80000

1.723079

29.4

21.1

9.85800

4.00000

1.622470

63.2

227.78200

±0.5

Infinity space

to the tube

lens

wherein lens group LG 42 is displaceable relative to lens group LG 41 within a length range of about ±0.5 mm extending in axial direction without causing a change in the magnification that is predetermined by this magnification system.

9. The optical arrangement according to claim 6 , with afocal magnification systems for a magnification of 0.87×, each comprising two lens groups LG 51 and LGS 52 with radius r, thickness d, distance a relative to one another, refractive index ne, Abbe number ve and focal length f′ with respect to the wavelength of 546.07 nm:

Variable

Refractive

Abbe

Focal

Radius

Thickness

distance

index

number

length

Lens group

r (mm)

d (mm)

(mm)

n e

v e

(mm)

Infinity space

to the

objective

LG51

−24.10700

2.00000

1.591420

61

50.2

23.71440

2.80000

1.723079

29.4

−16.3

−19.81190

0.98374

−18.36100

2.50000

1.761639

27.2

40.62800

0.57591 ± 0.5

LG52

45.31600

3.00000

1.591420

61

26.6

−23.5100

33.5

±0.5

Infinity space

to the tube

lens

wherein lens group LG 52 is displaceable relative to lens group LG 51 within a length range of about ±0.5 mm extending in axial direction without causing a change in the magnification that is predetermined by this magnification system.

10. The optical arrangement according to claim 1 , with tube lens systems with changeable transmission length, wherein the displaceable optical assemblies are lenses or lens groups of these tube lens systems.

11. The optical arrangement according to claim 10 , with tube lens systems, comprising lenses L 1 to L 3 with radius r, thickness d, distance a relative to one another, refractive index ne, Abbe number ve with respect to the wavelength of 546.07 nm:

Variable

Refractive

Radius

Thickness

distance a

index

Abbe number

Focal length

Lens

r (mm)

d (mm)

(mm)

n e

v e

f′

L1

273.65

4.0

1.622470

63.19

122.00

−104.52

11 ± 9

L2

−272.80

2.5

1.584820

40.56

−87.48

63.18

10 ± 9

L3

81.92

4.0

1.622470

63.19

131.00

infinity

181.66 ± 23.4 

Receiver

surface

wherein the total transmission length of the tube lens system and, therefore, the focus position and focusing on the receiver surface changes when the combination formed of lenses L 1 and L 3 on one hand and lens L 2 on the other hand are displaced relative to one another in axial direction within a length range of ±9 mm without causing a change in the predetermined magnification.

12. A method for calibrating the imaging of depth-structured objects using the optical arrangement indicated in claim 1 , comprising the steps of:

recording a series of images from different object distances for determining the change in the image geometry;

placing the object at different distances from the optical arrangement for this purpose; and

compensating for defocusing that is present after the adjustment of an object distance diverging from a preceding adjustment by displacing the optical assemblies.

13. The method for recording a series of images of objects of an object plane, which images have longitudinal chromatic aberrations, using the arrangement indicated in claim 1 , wherein a series of images is recorded at the same object distance successively in time and in a wavelength-selective manner, wherein the optical assemblies are displaced for purposes of compensating a defocusing associated with a determined wavelength.