Accession No
3114
Brief Description
pair of prisms, c.1900
Origin
Maker
Class
optical
Earliest Date
1900
Latest Date
1990
Inscription Date
Material
glass
Dimensions
triangle side 138mm; height 79mm; breadth 121mm
Special Collection
Provenance
Transferred from Institute of Astronomy, University of Cambridge, Cambridge, England, 12/1983.
Inscription
‘REFIGURED
HILGER
1931’ (both prisms)
Description Notes
Two 60˚ glass prisms; black on 3 sides; numbered ‘1’ and ‘2’.
Condition
References
Events
Description
Prism
A prism consists of a translucent piece of glass or crystal, usually triangular in cross section, which is used to separate light into a spectrum of its separate colours.
The instrument works because different wavelengths of light are refracted (bent) by different amounts as they enter and leave the prism; the shorter wavelengths (towards the blue end of the spectrum) are refracted by the greatest amount, and the longer wavelengths (towards the red end) are refracted the least. This spreads out normal white light, which is a mixture of all the different colours, into its constituent parts and produces the rainbow effect of a spectrum.
18/10/2002
Created by: Saffron Clackson on 18/10/2002
FM:43424
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