Microscope having dual remote image masking

摘要

A universal microscope for use with a commercial FT-IR spectrophotometer comprises a visible light microscope for selecting and masking an area of a sample and an infrared microscope for sampling the masked area. The visible light microscope and the infrared microscope share a common optical path between one or more remote sample image plane masks and the sample plane such that both the visible light and the infrared radiant energy are masked twice to spatially define the same area at the sample plane. The first sample image plane mask removes energy from outside the target area at the sample focus. The second sample image plane mask removes energy from outside the target area that is diffracted by the first mask or the focusing optics. The first remote sample image plane is imaged onto the second remote image plane with the radiant energy gaining spectroscopic information and additional image information by passing through or reflecting off a sample located at the intervening sample plane. Samples having a diameter of less than 8 microns have been spectroscopically isolated with 2-25 micron infrared radiant energy.