"echelle grating" meaning in English

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      "glosses": [
        "A form of diffraction grating optimized for high orders of diffraction"
      ],
      "id": "en-echelle_grating-en-noun-G9xDK5g6",
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          "diffraction grating",
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        "(physics) A form of diffraction grating optimized for high orders of diffraction"
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        "echelle grating"
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  "lang_code": "en",
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        "(physics) A form of diffraction grating optimized for high orders of diffraction"
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