Absolute linear-in-k spectrometer designs enabled by freeform optics Yoon, Changsik ; Bauer, Aaron ; Xu, Di ; Dorrer, Christophe ; Rolland, Jannick P. Abstract Publication: Optics Express Pub Date: November 2019 DOI: 10.1364/OE.27.034593 Bibcode: 2019OExpr..2734593Y