At the far end of the IR spectrum lies a previously little-used segment of the electromagnetic spectrum known as the terahertz region. The use of the terahertz region for spectroscopy offers advantages but faced technological limitations until recently. Numerous vendors have entered the market in the past several years. An incredibly diverse range of potential applications for the technique should lead to strong growth for the technology.

Terahertz spectroscopy utilizes the segment of the electromagnetic spectrum between IR and microwave regions, which includes wavelengths from 100 µm up to 1 mm, which corresponds to frequencies of ~0.3–~10 THz. A major advantage of the terahertz spectrum over other regions used in spectroscopy is that terahertz radiation can penetrate numerous materials, such as clothing, ceramics, paper, wood and concrete. In addition, almost all molecules have some spectrally significant characteristic in the terahertz region, and electromagnetic energy in the region does not lead to the photoionization of biological tissues. These characteristics make terahertz spectroscopy useful for a range of applications, including life science, materials analysis and security.

Although many in the scientific community have been familiar with the characteristics of the terahertz spectrum for decades, the technology to manufacture commercially viable instruments, particularly laser and detector technology, did not come into existence until fairly recently. The first commercial instrument was introduced in 2000 by Picometrix, with TeraView following suit soon thereafter. There are now more than half-a-dozen competitors in the market, as well as several vendors of terahertz laser sources and detectors.

The range of configurations of terahertz spectroscopy systems includes portable handheld models, imaging systems, time-domain instruments, models for process monitoring, security screening systems and benchtop spectrometers. The development of so many permutations of terahertz spectrometers is due to the previous development of such products for established spectroscopy techniques.

As with most new analytical technologies, academic research labs have the largest demand for terahertz spectroscopy, as they are exploring numerous potential applications for the technique. However, demand from the semiconductor and electronics industry is already starting to take off, due in part to interest from Intel for inspection applications. Many vendors offer terahertz instruments for use in analyzing the coatings of solid dosage-form drugs. There has also been interest in terahertz spectroscopy for security and defense applications. Several companies are also investigating terahertz spectroscopy’s potential in clinical and hospital settings, such as for surgeons to identify the edges of cancerous tumors.

The wide range of applications for terahertz spectroscopy will lead to strong growth beyond the $20 million market that existed in 2012.

Terahertz Spectroscopy at a Glance:

Leading Suppliers

• Picometrix (API)

• TeraView

• TOPTICA Photonics

Largest Markets

• Academia

• Semiconductor and Electronics

• Pharmaceutical

Instrument Cost

• $50,000–$400,000