Y 0 7 ray and the FOB 1, RAY 0 -8 ray at surface 5.</p>

<p>First the user-defined aberrations. We write the following macro
function named FUN01 by entering the following commands at the CMD
level:</p>

<p><strong>
    MACRO FUN01<br>
    C FIRST THE SUM OF THE SQUARES OF PY AND PCY AT SURFACE 3 (STORE IN #1)<br>
    GET PY 3<br>
    ENT<br>
    GET PY 3<br>
    C MULTIPLY<br>
    *<br>
    STO 1<br>
    GET PCY 3<br>
    ENT<br>
    GET PCY 3<br>
    C MULTIPLY<br>
    *<br>
    C STORE PLUS INTO REG 1<br