Tunable Laser Spectroscopy
Goal
To develop a high performance spectroscopy system based on tunable laser illumination and detection of reflected or transmitted signals. Chemistry and structure of the sample can be determined, based on optical response to illumination. The technology supports rapid acquisition of data from the surface or interior of samples. The technology is non-invasive when used to detect interior features or composition. The technology can be applied to areas, supporting imaging functions.
Technology
We are developing a wavelength-tunable laser system. In comparison to traditional spectroscopic broadband sources, lasers provide substantial advantages, including:
- Higher power density
- Higher degree of coherence
- Better directionality
These attributes increase the throughput and the measurements sensitivity significantly, which could lead to high-speed, high-sensitivity 3-D tissue spectroscopic imaging.
Utilizing beam-expander optics, a CCD sensor array, and real-time signal processing, tissue imaging can be performed without the need for 2-D scanning of the platform.
Benefits
- Provide high spectral brightness (up to 103 - 104 times higher than broadband sources), which enables measurement of weakly absorbing samples undetected by lamp-based spectroscopic systems
- The ability to obtain both structural and chemical information of the tissue volume under investigation (as opposed to only the structural information obtained by a conventional white-light imaging system)
- Potentially replace 2-D scanning of the conventional spectroscopic imaging system, which are inherently slow, and are prone to motion artifacts
Potential Applications
- Tissue analysis
- Trace-gas analysis
- Agricultural produce characterization
- Biological sample analysis
Results
A modular tunable laser system prototype has been designed and built. It consists of a frequency-doubled Nd:YAG pump laser and an optical parametric oscillator (OPO). Output wavelength is tuned by rotating a nonlinear crystal on a computer-controlled precision rotary stage inside the OPO.
Initial measurements suggest that the system is tunable between ~700nm up to ~2300nm, with excellent wavelength stability. This wavelength range is suitable for biological samples such as blood, skin and tissue.
Opportunities
Delta Search Labs is interested in working with researchers or device manufacturers to address testing, manufacturing and distribution of devices based this technology.
We are also interested in opportunities to apply this technology in a wide range of biological, chemical or process applications.