New opportunities exist to obtain chemical images using attenuated total reflection infrared (ATR-IR) spectroscopy. This paper shows the feasibility of obtaining FT-IR images with a spatial resolution of
at least 3-4 μm using a Ge ATR objective coupled with an infrared microscope. The improved spatial resolution compared to FT-IR images obtained by the transmission method is due to the high refractive
index of the ATR crystal, which gives a high numerical aperture and hence, a higher spatial resolution. FT-IR imaging with a conventional diamond ATR accessory has been investigated. This is the first time
that FT-IR imaging is reported using such a versatile accessory based on a diamond ATR crystal. These results showed that a spatial resolution up to 13 μm can be achieved without the use of infrared
microscope objectives. One advantage of the diamond element is that it allows pressure to be applied and hence, good contact to be obtained over the whole field of view.
Department of Chemical Engineering and Chemical Technology, Imperial College London, London, SW7 2AZ, UK
Publication date: April 1, 2003
More about this publication?
The Society publishes the internationally recognized, peer reviewed journal, Applied Spectroscopy, which is available both in print and online. Subscriptions are included with membership or can be purchased by institutional or corporate organizations. Abstracts may be viewed free of charge. Previously published as Bulletin (Society for Applied Spectroscopy)