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We proposed the extremely compact beans-size snap-shot mid-infrared spectroscopy that will be able to be built in
smartphones. And also the easy preparation method of thin-film samples generated by ultrasonic standing wave is
proposed. Mid-infrared spectroscopy is able to identify material components and estimate component concentrations
quantitatively from absorption spectra. But conventional spectral instruments were very large-size and too expensive to
incorporate into daily life. And preparations of thin-film sample were very troublesome task. Because water absorption
in mid-infrared lights is very strong, moisture-containing-sample thickness should be less than 100[μm]. Thus, midinfrared
spectroscopy has been utilized only by analytical experts in their laboratories. Because ultrasonic standing wave
is compressional wave, we can generate periodical refractive-index distributions inside of samples. A high refractiveindex
plane is correspond to a reflection boundary. When we use a several MHz ultrasonic transducer, the distance
between sample surface and generated first node become to be several ten μm. Thus, the double path of this distance is
correspond to sample thickness. By combining these two proposed methods, as for liquid samples, urinary albumin and
glucose concentrations will be able to be measured inside of toilet. And as for solid samples, by attaching these apparatus
to earlobes, the enhancement of reflection lights from near skin surface will create a new path to realize the non-invasive
blood glucose sensor. Using the small ultrasonic-transducer whose diameter was 10[mm] and applied voltage 8[V], we
detected the internal reflection lights from colored water as liquid sample and acrylic board as solid sample.
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