Yukihiro Ishii

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Accurate measurement of large step heights using multiple-wavelength holographic interferometry is realized using laser diodes. Due to the high-resolution wavelength tunability of such lasers, a pair of holograms with a wavelength difference of less than 0.01 nm is recorded and used to extract a phase difference having a large synthetic wavelength. Phase(More)
Here we present multiple-wavelength digital holographic interferometry with a wide measurement range using laser diodes. Small wavelength differences can be easily realized by the wavelength tuning of laser diodes with injection current controls. A contour map of an object with a wide measurement range and a high sensitivity is demonstrated by combining a(More)
Fringe counting method with laser diodes (LDs) for displacement measurement has been constructed. Two LDs are frequency modulated by mutually inverted sawtooth currents on an unbalanced two-beam interferometer. The mutually inverted sawtooth-current modulation of LDs produces interference fringe signals with opposite signs for respective wavelengths. The(More)
OBJECTIVE Patients with schizophrenia have increased risk of atherosclerotic diseases. It is already known that lifestyle-related disorders and the use of antipsychotics are closely related with the progression of atherosclerosis in psychiatric patients. Stroke as well as coronary heart disease play an important role in the cause of death in Asia and Japan.(More)
A phase-shift-locked interferometer has been constructed for distance measurement. A phase shift produced by sawtooth-current modulation of a laser diode is locked to a phase difference preset by polarization optics that consists of a quarter-wave plate and polarizers through an electrical feedback technique. An optical path difference can be measured from(More)
BACKGROUND We clarified the correlation between brain damage, associated biomarkers and medication in psychiatric patients, because patients with schizophrenia have an increased risk of stroke. METHODS The cross-sectional study was performed from January 2013 to December 2015. Study participants were 96 hospitalized patients (41 men and 55 women) in the(More)
Using a scanning electron microscope, we studied the surface structure of 5 different central nuclei, isolated by repeated hydrodissection during extracapsular cataract extraction. Aside from the damage induced by surgical maneuvers, the surfaces were very smooth, and there was no major disruption of the lamellar structure of the lens. Our studies have(More)
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