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APPENDIX 1 2 3 4: Telescope eyepiece specifications

                 D=diameter   f=f.l./D   K=conic   R=surface radius   S=separation   M=medium   A=air   RI=best image curvature   A4/A6=aspheric coefficients  T=tilt (deg.)

TELESCOPE_EYEPIECES

f(mm)

FD*

R1**

S1 

M1

R2   

S2

M2

R3 

S3

M3

R4

S4

M4

R5

S5

M5

R6

S6

M6

RI

1. Huygens

20

-5.8

18

3

BK7

0

20

A

9

2

BK7

0

3.1

A

-

-

-

-

-

-

18

2. Ramsden  

20

0

4

BK7

-14 

18 

A

14

2.5

BK7

0

8

A

-

-

-

-

-

-

60

3. Monocentric  

20

8.3

11.6

6.3

F2

5.3

10.6

BK7

-5.3 

6.3

F2

-11.6

9

A

-

-

-

-

-

-

18

4. Kellner  

20

5.8

0

3.8

BAK2

-17

16

A

14

6

BAK2

-10

1.4

 F4

0

9.5

A

-

-

-

100

5. K�nig  

astigmatic

20

12.9

-31.9

1.5

SF4

15.2

6.1

SK10

-18.2

0.1

A

20.5

3.8

SK2

64.6

21.3

A

-  

-

-

230

comatic

20

12.9

-42.5

1.9

SF4

15.8

5

SK10

-19.3

0.13

A

20.8

6

SK2

86.6

7.6

A

-

-

-

-36

6. Erfle  

20

11.6

-55

1.7 

SF12

22.6

6.6

PSK3

-30

0.1

A

41

6.6

FK5

-41

0.1

A

19

6.6

PSK3

   

 R7 /S7 /M7  -  R8 /S8 /M8  -29/1.7/SF10  - 166/ 15/A

100

7. Abbe  

20

11.2

26.7

7.1

BAF5

-16 

1.8

SF14

16

7.1

SK7

-24.9

0.1

A

26.7

4.45

SF10

0

16.4

A

60

8. Pl�ssl  

20

14.3

0

1.8

SF19

18.4

7.4

SK11

-19.3

0.1

A

19.3

6.4

SK11

-18.4

1.8

SF19

0

 15.6

A

70

9. Achromat pair  

20

14.7

0

2

F4

19

6

BaK2

-19

0.1

A

19

6

BaK2

-19

2

F4

0

18

A

10. Single lens pair  

20

20.2

0

3

BK7

-21

0.1

A

21

3

BK7

0

20

A

        

  

   

     

  

-

24

*Front distance: field lens front surface to objective's image separation (last separation S is the eye relief)    **Front field lens radius

Human Eye: Optical model

Dmm

f/

R1

S1

M1

R2

S2

M2

R3

S3

M3

R4

S4

M4

R5

S5

M5

R6

S6

M6

RI

  

1-7

20-3

7.3

0.45

Silica

5.6

2.8

Water

0* 

0  

Water

500**

0.6

Pyrex

2.6

4

Silica

-6.3

~20

Water

-12.5

*aperture stop    **cylinder

Eyepieces from FIG.216

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