Spectrophotometric Attachment for the Vacuum Ultraviolet

An absorption spectrophotometric attachment to a vacuum ultraviolet monochromator has been built and tested. With an empty sample chamber, the ratio of the radiant flux through the sample chamber to the radiant flux through the reference chamber was measured. By optimizing conditions at the entrance slit, the ratio was constant within experimental error over the region 1000–1600 A. The transmittance of thin celluloid films was measured with the attachment.