For Industry

Optical Coherence Tomography (OCT) is a non-invasive imaging technology used for performing high-resolution cross-sectional imaging.  OCT utilizes infrared light (in the range of approximately 800 to 1300 mm).  The image produced from OCT is constructed by measuring the echo time delay and wavelength of light backscattered or back-reflected from the material being imaged.  The resolution of OCT is significantly higher than ultrasound technology.  

Researchers at Lehigh University have developed an enhancement to OCT that can achieve significant improvement of imaging speed without losing image sensitivity.  The approach utilizes space-division multiplexing technology that translates the long coherence length of a commercially available tunable laser into high OCT imaging speed.  The achievement of an effective 800,000 A-scans/s imaging speed using a commercially available 100,000 Hz tunable VCSEL light source and a single detection channel has been demonstrated in research studies.  

The core element of the approach is splitting the imaging beam to illuminate multiple physical locations of the material being imaged simultaneously.  Each beam that is split is optically delatyed so that when images are formed, signal from different physical locations is detected in different frequency bands of the detection system.  This enables parallel detection of signals from multiple imaging points leading to significantly improved imaging speed.

The invention introduces a method for fabricating ferroelectric crystal lines for use as low loss optical waveguides with additional active functionality compared to amorphous/glass waveguides it provides low losses by confining the light signal tightly in the crystal core, away from the rough crystal-glass interface that is often responsible for losses in such a system.  These ne types of waveguides consisting of active crystals, such as lithium niobate, in glass, can be fabricated in complex architecture, suitable for realizing integrated optical elements within the glass substrate at low cost GRISC waveguides have much lower losses than other competing options.  

The GRISC in glass is created through control of the temperature distribution induced by femtosecond laster heating.  Within the glass, the femtosecond laser induced temperature profile allows for crystallization upon heating, ahead of the laser focus.  The refractive index contrast generated using this method leads to tight optical confinement of the transmitted light in a Gaussian profile.  Such a profile results in most of intensity in the center where losses are low, and very low intensity near the crystal-glass interface where losses tend to be high. 

This invention describes an engineered nanostructure and method for bioactive glasses used for bone scaffolds and other biomedical applications.  The inventors have developed and patented a melt-quench-heat-etch (MQHE) method that is closely related to standard glass production technology.  More recently, the inventors have discovered that in addition the specific glass composition, the nanostructure can greatly influence the biomedical performance.  Specifically, they have demonstrated superior in vitro performance of widely used 45S5 glass with an interconnected spinodally phase-separated nanostructure than with isolated droplets in a matrix (cells respond more favorably to the morphology and composition with the superior nanostructure).  This concept can be extended to other bioactive silicate glass compositions that are prone to phase separation (e.g., derivatives of 45S5 doped with certain oxides or different ratios of its constituents).  Also, the nanostructure can be further manipulated by controlling the melt cooling process (melt temperature, mold temperature, casting procedure, batch size, heat treatment, etc.).

This invention describes a process of preparing calcium and magnesium salt - urea compounds using a solution free route.  Urea is a large volume nitrogen containing fertilizer but suffers from the propensity to hydrolyze in soil thus resulting in nitrogen losses to environment.  Encapsulating urea in a crystalline compound together with inorganic acids, such as H3P04 and H2S04 has been shown to significantyly decrease urea losses to the environment.  Reports have shown that a molecular adduct of urea and phosphoric or nitric acid result in only a 0.7% nitrogen loss as ammonia as opposed to up to 61.1% of soil treated with urea only, suggesting major improvements in sustainable management of the global nitrogen cycle.  Additionally, urea molecular adducts with inorganic Mg and Ca salts also contain other primary and secondary nutrients, such as P, Ca, Mg and S, necessary for a balanced nitrogen uptake.