This Small Business Technology Transfer (STTR) Phase I research project proposes a tunable dye laser for optical sensing based on the innovative dye-doped Holographic Polymer Dispersed Liquid Crystals (HPDLC) technology. The demonstration of the tunable lasing of dye-doped HPDLC is the main focus during the Phase I research. By carefully choosing the materials including liquid crystal, polymerizable monomer, emitter dye and optimizing the holographic-writing process, dye-doped HPDLC is formed as an one-dimensional photonic bandgap material, mirrorless lasing in the dye-doped HPDLC occurs at the reflection band edges. Applied voltage tunes the reflection peak of the HPDLC as well as the center wavelength of emitting laser. The whole laser device is solid state and highly resistant to shock and vibration as it has no moving parts. Since the innovative laser device is based on the thin film technology, there is no bulky laser cavity. The manufacturing unit cost of the HPDLC thin film can low due to easy-to-achieve large scale manufacturing that it is economical to throw away and replace a HPDLC thin film device once the dye reaches the end of its life.
This innovative tunable laser will have applications in optical sensing in areas such as hyper-spectral medical imaging and bio-imaging where different color signals the biochemical makeup of different regions of tissue, nuclei, cytoplasm, etc. Additionally this laser can be used to create inexpensive and perhaps disposable Raman sensors and imagers for use in the biological, medical and chemical sensing markets. The proposed tunable laser is especially useful in LIDAR, atmospheric sensing and planetary exploration when wavelength agility is required. One specific application is for on-orbit LIDAR systems, for example mapping planetary surfaces because of its great advantage of small size, low weight and shock/vibration resistance. Such a small laser could be used on surface rovers enabling surface Raman spectroscopy and LADAR mapping. In addition, this innovative tunable laser will bring a great improvement in high quality laser display with merits of high color purity and high light intensity. Its role as a tunable signal source in optical communication such as Wavelength Division Multiplexing (WDM) is another commercial application.