Minor fix

Signed-off-by: ClemensLinnhoff <[email protected]>

content/09_annexes/checker-rules.adoc

@@ -174,13 +174,13 @@ Description:: A temperature in Kelvin (K) shall not be below 0.
 
 UID:: asam.net:xom-mat:1.0.0:xompt.real_part_ior_valid_range
 
-Description:: The real part of index of refraction (refractive index n) shall not be below 0.
+Description:: The real part of the index of refraction (refractive index n) shall not be below 0.
 
 ==== imaginary_part_ior_valid_range
 
 UID:: asam.net:xom-mat:1.0.0:xompt.imaginary_part_ior_valid_range
 
-Description:: The imaginary part of index (extinction coefficient k) of refraction shall not be below 0 (= perfect transparent material).
+Description:: The imaginary part of the index (extinction coefficient k) of refraction shall not be below 0 (= perfect transparent material).
 
 ==== humidity_valid_range
 
@@ -210,7 +210,7 @@ Description:: The real part of the relative permittivity shall not be below 1.
 
 UID:: asam.net:xom-mat:1.0.0:xompt.imaginary_part_permitivity_valid_range
 
-Description:: The imaginary part of permittivity shall not be below 0.
+Description:: The imaginary part of the relative permittivity shall not be below 0.
 
 ==== incident_elevation_angle_valid_range