Improved Imaging System for Medicine, Research, and Industry
Researchers affiliated with the NSF-funded Engineering Research Center (ERC) on Mid-Infrared Technologies for Health and the Environment (MIRTHE), which is headquartered at Princeton University, have demonstrated progress in developing a system to produce improved images of materials samples. These types of images are used extensively in medicine, research, and industry.
Current imaging systems use two kinds of light reflected at different depths in a sample to obtain high-resolution, 3-D images. The ERC researchers are pursuing development of a system using a third kind of light, which would decrease scattering and give stronger reflections of images from samples of materials that have matching light-absorption properties.
Optical Coherence Tomography (OCT) systems now rely on use of visible and near-infrared (near-IR) light; mid-IR light would produce better images, but no mid-IR systems are commercially available. The researchers’ focus on development of a system employing mid-IR light has resulted in the design, assembly, and test of a first experimental system that can sense spatial information (sample depth) as well as absorption spectra.
Development emphasis is on a new high-power (up to 100 mW), low-coherence (less than 100 μm), super-luminescent quantum-cascade emitter to achieve both long depth range and high depth resolution. This emitter is a key element of the new mid-IR OCT system demonstration (see figure).