[Author Prev][Author Next][Thread Prev][Thread Next][Author Index][Thread Index]

Re: [ATM] Luri-Houghton prescriptions.



Ukyo Chen wrote:

>Different:
>
>*LENS DATA
>No name
>SRF      RADIUS      THICKNESS   APERTURE RADIUS       GLASS  SPE  NOTE
>OBJ       --        1.0000e+20    1.0472e+18             AIR
>
>AST   2.2035e+03 V   20.000000    159.000000 ASX         BK7 C
>  2    3.1078e+03 V   15.000000    159.000000 P           AIR
>
>  3   -1.2563e+03 V   15.000000    159.000000 P           BK7 P
>  4   -1.5177e+03 V  1.2800e+03    159.000000 P           AIR
>
>  5   -2.9250e+03   -1.2000e+03 P  172.827007 S    REFL_HATCH
>
>  6        --        159.000000     43.720519 S    REFL_HATCH
>
>  7        --        104.887242 S   26.613909 S           AIR
>
>  8        --            --         15.329223 S           AIR
>
>IMS       --            --         15.329223 S
>
I have suggested a design short of that; one that minimizes glass use --
leave the last surface flat.  In that way, it still fits into the smallest
possible lens blank while providing a more optimal design:

Surf      Radius      Thickness      Glass      Diameter
 OBJ    Infinity       Infinity                        0
 STO    Infinity     -0.1676269                     12.5
   2       116.6           0.78      N-BK7            13
   3      -424.4           0.19                       13
   4       -91.4           0.55      N-BK7            13
   5    Infinity           50.5                       13
   6        -119          -48.5     MIRROR         13.75
   7    Infinity      -10.95741                 3.963536   (secondary)
 IMA   -170.4668                                1.700382

The first surface has radius close to that of the mirror.  Under
the constraints of this design, and by selecting a different refractive
index and a different f/#, these can be made to match (the refractive
index here is the RMS mean refractive index in the visual band; it
actually works out to be the refractive index of the glass at about
554.4 to 554.5 nm):

f/5.551, n = 1.518303:

Surf      Radius      Thickness      Glass      Diameter
 OBJ    Infinity       Infinity                        0
 STO    Infinity     -0.1411938                     12.5
   2       138.4           0.78      N-BK7            13
   3      -455.5           0.16                       13
   4      -106.1           0.58      N-BK7            13
   5    Infinity           60.2                       13
   6      -138.4          -58.2     MIRROR         13.75
   7    Infinity      -10.95756                 3.650144
 IMA   -186.2714                                1.700268

f/5.391, n = 1.524130:

Surf      Radius      Thickness      Glass      Diameter
 OBJ    Infinity       Infinity                        0
 STO    Infinity     -0.1453896                     12.5
   2      134.41           0.78       N-K5            13
   3      -455.2           0.17                       13
   4      -103.7          0.576       N-K5            13
   5    Infinity         58.205                       13
   6     -134.41        -56.205     MIRROR         13.75
   7    Infinity       -10.9603                 3.707734
 IMA   -182.8639                                1.700296

f/5.378, n = 1.524749:

Surf      Radius      Thickness      Glass      Diameter
 OBJ    Infinity       Infinity                        0
 STO    Infinity     -0.1457587                     12.5
   2      134.07           0.78       B270            13
   3      -455.4           0.17                       13
   4      -103.5          0.576       B270            13
   5    Infinity         58.035                       13
   6     -134.07        -56.035     MIRROR         13.75
   7    Infinity      -10.96189                 3.713051
 IMA   -182.5092                                  1.7003

f/4.990, n = 1.541650:

Surf      Radius      Thickness      Glass      Diameter
 OBJ    Infinity       Infinity                        0
 STO    Infinity     -0.1571661                     12.5
   2      124.35           0.78     N-BAK2            13
   3      -459.6           0.18                       13
   4      -97.78          0.563     N-BAK2            13
   5    Infinity         53.175                       13
   6     -124.35        -51.175     MIRROR         13.75
   7    Infinity      -10.96107                 3.868029
 IMA   -175.0516                                 1.70036

f/4.472, n = 1.570727:

Surf      Radius      Thickness      Glass      Diameter
 OBJ    Infinity       Infinity                        0
 STO    Infinity     -0.1754636                     12.5
   2       111.4           0.78     N-BAK4            13
   3      -480.7            0.2                       13
   4      -90.35          0.546     N-BAK4            13
   5    Infinity           46.7                       13
   6      -111.4          -44.7     MIRROR         13.75
   7    Infinity      -10.95422                 4.114689
 IMA   -164.9338                                1.700476





_______________________________________________
ATM mailing list http://www.atmlist.net/