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An infrared (IR) thermal camera may provide a tool for real-time temperature monitoring for precise disease treatment using heat generated by light-induced photosensitisers, i.e. photothermal/ablation therapies. In this work, we quantitatively demonstrated that the spatial resolution of a low-cost low-resolution IR camera could be improved via two deconvolution methods. The camera point spread function (PSF) was modeled experimentally and used to develop the deconvolution methods: 1) Richardson-Lucy blind deconvolution (BD); and 2) total variation constrained deconvolution (TD). The experimental results showed the improved spatial resolution (at 50% modulation transfer function (MTF): from the original 1.1 cycles/mm to 2.6 cycles/mm for the BD method and to 4.8 cycles/mm for the TD method) as well as contrast-to-noise ratio. With a properly chosen parameter, the TD method can resolve 1-mm size objects with the accurate temperature reading. The thermal image from the low-resolution IR camera enhanced by the TD method is comparable to that from a high-resolution IR camera. These results show that the TD method provides an effective way to improve the thermal image quality from a low-cost IR camera to monitor temperature of an object of 1-mm size, which meets the needed precision for advanced laser scanning protocols in photothermal/ablation therapies.

A novel method for the preparation of bamboo fibers (BF) has been investigated that includes crushing, rolling, and other combing techniques with 1,4-butanediol as a dispersant. The fibers were treated by oxygen plasma to improve their interfacial adhesion to unsaturated polyester (UPE) resins. Composites were prepared from the plasma treated fibers (BFtr) and UPE by hand lay-up compression molding. BFtr significantly increased the tensile strength, flexural strength, and flexural modulus of the resulting BF-UPE composites. Dynamic mechanical analysis indicated that the plasma treatment essentially increased the storage modulus and glass transition temperature of the composites. The damping parameter of the composites showed a decreasing trend in the glassy region, while the opposite was true for the rubbery region. X-ray diffraction analysis indicated that the treatment did not change the crystal structures within the fibers but increased slightly their crystallinity indices. X-ray photoelectron spectroscopy analysis revealed that the surface of BFtr had a higher oxygen concentration and oxygen/carbon ratio than that of BF. The scanning electron microscopy graphs of the tensile-fractured surface of the composites demonstrated an improved interfacial adhesion between BFtr and UPE resins.