{
  "annotation_id": "60477941-0d80-4495-acfd-cec462d0927f",
  "date_created": "2026-03-02T18:00:52.605000Z",
  "date_modified": "2026-03-02T18:00:52.605000Z",
  "file_hash": "a8b66e756c0d2c438986e340de406228139ee8cfedc0f4c69c88dab5dc195728",
  "private": false,
  "record": {
    "abstract": "We show that the problem of finding the primary and secondary characteristic\ndirections of a linear lossless optical element can be reformulated in terms of\nan eigenvalue problem related to the unimodular factor of the transfer matrix\nof the optical device. This formulation makes any actual computation of the\ncharacteristic directions amenable to pre-implemented numerical routines,\nthereby facilitating the decomposition of the transfer matrix into equivalent\nlinear retarders and rotators according to the related Poincare equivalence\ntheorem. The method is expected to be useful whenever the inverse problem of\nreconstruction of the internal state of a transparent medium from optical data\nobtained by tomographical methods is an issue.",
    "arxiv_id": "physics/0408069",
    "authors": [
      "Hanno Hammer"
    ],
    "categories": [
      "physics.optics",
      "physics.ins-det"
    ],
    "doi": "10.1080/09500340500058199",
    "journal_ref": "Journal of Modern Optics, Vol. 52, No. 11, 20 July 2005, 1597 -\n  1610",
    "title": "Determination of the characteristic directions of lossless linear   optical elements",
    "url": "https://arxiv.org/abs/physics/0408069"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "ed99723b-9c07-496d-87ff-4227ffbc6bdb",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}