transmission grating on semicircular optical flat
Datecirca 1940
Inventory Number1996-1-0481r
ClassificationDiffraction Grating
Subject
Maker
American
Maker
Harvard College Observatory
founded 1839
Cultural Region
Place of Use
Dimensions7.6 × 15.7 × 0.6 cm (3 × 6 3/16 × 1/4 in.)
Material
Description1996-1-0481r and 1996-1-0481s are semicircular plates of flat glass with rough cut edges coated with a black material. One face of the glass has a thin coating, which makes the glass disperse light into the spectrum on reflection from that surface or transmission through that surface. The coating is likely a transmission grating on a film adhered to the glass.
Signedunsigned
ProvenanceHarvard College Observatory, Agassiz Station; transfer to CHSI in 1969.
Historical AttributesThis optical element was used by Harvard College Observatory and came from Agassiz Station.
American
Date: circa 1940
Object number: 1996-1-0481s
R. W. Jool
Date: 1910-1920
Object number: 2053
Jarrell-Ash Company
Date: circa 1946
Object number: 2052a
