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                <front>
                    <journal-meta>
                    <journal-id journal-id-type="publisher-id">lim</journal-id>
                    <journal-title>London Imaging Meeting</journal-title>
                    <issn pub-type="ppub">2694-118X</issn><issn pub-type="epub">2694-118X</issn>
                    <publisher>
                        <publisher-name>Society for Imaging Science and Technology</publisher-name>
                        <publisher-loc>IS&amp;T 7003 Kilworth Lane, Springfield, VA 22151 USA</publisher-loc>
                    </publisher>
                    </journal-meta>
                    <article-meta>
                    <article-id pub-id-type="doi">10.2352/lim.2023.4.1.09</article-id>
                    <article-id pub-id-type="publisher-id">9</article-id>
                    <article-categories>
                        <subj-group>
                        <subject>Proceedings Paper</subject>
                        </subj-group>
                    </article-categories>
                    <title-group>
                        <article-title>Performance Considerations for Ray Tracing in Gradient-index Optics with Symplectic Numerical Methods</article-title>
                    </title-group><contrib-group content-type="all"><contrib contrib-type="author"><name>
                            <surname>McKeon</surname>
                            <given-names>Ben </given-names>
                           </name> <xref ref-type="aff" rid="aff1author1"/></contrib><aff id="aff1author1">University of Galway, Ireland</aff></contrib-group><contrib-group content-type="all"><contrib contrib-type="author"><name>
                            <surname>Goncharov</surname>
                            <given-names>Alexander V.</given-names>
                           </name> <xref ref-type="aff" rid="aff1author2"/></contrib><aff id="aff1author2">University of Galway, Ireland</aff></contrib-group><abstract>
                    <title>Abstract</title>
                    <p>The primary objective of this paper is to demonstrate the utility of symplectic numerical techniques for ray tracing within gradient-index media. The relevant mathematics are explained in brief, deriving the optical Hamiltonian independently of the Lagrangian optical formalism before constructing a symplectic ray tracing algorithm. Numerical experiments with the Luneburg and Maxwell fish-eye lenses compare the effectiveness of symplectic methods with standard numerical integration techniques, challenging the idea that the increased accuracy of higher-order numerical methods justifies their elevated computational cost. Further uses for symplectic ray tracing are also discussed.</p>
                    </abstract><pub-date>
                        <day>29</day>
                        <month>06</month>
                        <year>2023</year>
                        </pub-date><volume>4</volume>
                    <issue-acronym>LIM</issue-acronym>
                    <issue-title>London Imaging Meeting 2023: Material Appearance Final Program and Proceedings</issue-title>
                    <issue seq="9">1</issue>
                    <fpage>35</fpage>
                    <lpage>39</lpage>
                    <permissions>
                         <copyright-statement></copyright-statement>
                        <copyright-year>2023</copyright-year>
                    </permissions><kwd-group><kwd>GRIN lenses</kwd><kwd>Numerical ray tracing</kwd><kwd>Optics</kwd><kwd>Symplectic numerical methods</kwd></kwd-group></article-meta>
                </front>
                </article>