Page 47 - Modern Optical Engineering The Design of Optical Systems
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30   Chapter Two

        and approximate calculations would have been in even better agree-
        ment, yielding an image thickness of 2.502 in.

        2.4  A Collection of Imagery Equations

        These equations are derived from the newtonian and gaussian equations
        in this chapter. See Fig. 2.6.
        Newtonian:

                        2
                   x′   f /x       x   f /x′      f 5  22xxr
                                         2
                   x′   mf         x   f/m       m   f/x   x′/f
        Gaussian:
        (1/s′)   (1/f)   (1/s)
           s′   sf/(s   f)           s   s′   f/(f   s′)  f   s   s′/(s   s′)
           s′   f(1   m)             s   f(m   1)/m

                                                  2
           T ≡ s′   s                T   f(m   1) /m
                                                   2
            f   Tm/(m   1)  2        s 5 [2T6 2sT 2 4fT d ]/2
          f/#   1/[2(u   u′)]            1/[2 (m   1) NA′]
                                         m/[2(m   1) NA]
           u′   1/[2 (f/#) (m   1)]      u/m                m   u/u′
            u   m/[2 (f/#) (m   1)       mu′
          NA   m/[2(m   1) (f/#)]  NA′   1/[2(m   1)(f/#)]  NA′   NA/m

        Where  f is the focal length (EFL)
                s and s′ are the object and image distances from the principal
                points
                x and  x′ are the object and image distances from the focal
                points
                T   (s′   s)   track length (object to image distance)
                f/#   relative aperature   f/diameter


                                 Optical
                                 system
           Object
             h
                    m  F 1      P 1  P 2     F 2  (−)µ′
                 (−)x       (f)          (f)         x′
                                                               (−)h′
                      (−)s                      s′
                                  Null    T                  Image
                                 space
        Figure 2.6 The meaning of the symbols of Sec. 2.4.
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