"dark field illumination"@en-us . . "dark ground illumination"@en-us . . "00645622-n"^^ . "0"^^ . . . . . . . "100609290"@en-us . . "a form of microscopic examination of living material by scattered light; specimens appear luminous against a dark background"@en-us . . "0"^^ . "dark ground illumination"^^ . . "100645622"^^ .