1 files changed, 21 insertions, 0 deletions
diff --git a/axial/lens.m b/axial/lens.m
new file mode 100644
index 0000000..a75b2f4
--- /dev/null
+++ b/axial/lens.m
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+%---------------------------------------------------------------
+% Returns the ABCD matrix for propagation through a thin lens.
+%
+% SYNTAX: abcd=lens(f);
+%
+%
+% f = lens focal length
+%
+% abcd = |  1    0 |
+%        |-1/f   1 |
+%
+%---------------------------------------------------------------
+% SYNTAX: abcd=lens(f);
+%---------------------------------------------------------------
+
+function abcd=lens(f)
+
+abcd=[
+    1       0
+    -1/f    1
+];
+\ No newline at end of file