Heterodyne Angle Deviation Interferometry in Vibration and Bubble Measurements
نویسندگان
چکیده
We proposed heterodyne angle deviation interferometry (HADI) for angle deviation measurements. The phase shift of an angular sensor (which can be a metal film or a surface plasmon resonance (SPR) prism) is proportional to the deviation angle of the test beam. The method has been demonstrated in bubble and speaker’s vibration measurements in this paper. In the speaker’s vibration measurement, the voltage from the phase channel of a lock-in amplifier includes the vibration level and frequency. In bubble measurement, we can count the number of bubbles passing through the cross section of the laser beam and measure the bubble size from the phase pulse signal.
منابع مشابه
Recording depth and signal competition in heterodyne interferometry.
A common way to measure submicroscopic motion of the organ of Corti is heterodyne interferometry. The depth over which vibration can be accurately measured with heterodyne interferometry is determined by both the optics, which controls to what extent light from nonfocal planes reaches the photodetectors, and demodulation electronics, which determines to what extent signal generated by out-of-fo...
متن کاملSignal competition in optical coherence tomography and its relevance for cochlear vibrometry.
The usual technique for measuring vibration within the cochlear partition is heterodyne interferometry. Recently, spectral domain phase microscopy (SDPM) was introduced and offers improvements over standard heterodyne interferometry. In particular, it has a penetration depth of several mm due to working in the infrared range, has narrow and steep optical sectioning due to using a wideband light...
متن کاملA method for measuring the complex refractive index and thickness of a thin metal film
ABSTRACT A circularly polarized heterodyne light beam is incident on a thin metal film, causing successive reflections and refractions to occur at the two sides of the thin film. The phase difference between pand s-polarizations of the multiple-beam interference signal can be measured accurately with an analyzer and heterodyne interferometry. The phase difference depends on the azimuth angle of...
متن کاملModeling and Analysis of Phase Fluctuation in a High-Precision Roll Angle Measurement Based on a Heterodyne Interferometer
Heterodyne interferometry is a high-precision method applied in roll angle measurements. Phase metering is essential for high precision. During a high-precision measurement, a phase fluctuation appears even when the roll angle does not vary, which has never been analyzed before. Herein, the reason for the phase fluctuation is revealed, which results from the frequency-difference fluctuation and...
متن کاملA Comparison of Electronic Heterodyne Moire Deflectometry and Electroni,; Heterodyne Holographic Interferometry for Flow Measurements
Electronic heterodyne moire deflectometry and electronic heterodyne holographic interferometry are compared as methods for the accurate measurement of refractive index and density change distributions of phase object p . Experimental results are presented to show that the two methods have comparable accuracy for measuring the first derivative of the intE-ferometric fringe shift. The phase objec...
متن کامل