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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	4	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. König	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. Plössl		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

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