reference (ThicknessReferences)

b2boptic → items → item → pair → lens → geometry

values	description
CENTER	minimal thickness at the center of the lens
EDGE	minimal thickness at the edge of the lens
DRILLHOLE	minimal thickness at all drillholes

<xs:simpleType name="ThicknessReferences">
  <xs:restriction base="xs:string">
    <xs:enumeration value="CENTER" />
    <xs:enumeration value="EDGE" />
    <xs:enumeration value="DRILLHOLE" />
  </xs:restriction>
</xs:simpleType>