98%
921
2 minutes
20
In this work, we demonstrated a novel and low-cost full-range optical coherence tomography (FROCT) method. In comparison with the off-pivot approach, which needs precise control of the deflecting distance and should be adjusted for different situations, our proposed method is more flexible without regulating the system itself. Different from the previous systems reported in the literature, which used a high-cost piezo-driven stage to introduce the phase modulation, our system utilizes a cost-effective voice coil motor for retrieving the complex-valued spectral signal. The complex-valued data, with a twofold increase in the accessible depth range, can be calculated using an algorithm based on the Hilbert transform and Dirac delta function. To confirm the effectivity of our method, both simulation and experiments were performed. In particular, for the in vivo experiment, we presented the FROCT result of a fingernail fold, demonstrating the availability of in vivo imaging. Since the key element of our system is a low-cost voice coil motor, which is flexible and more accessible for most of the clinics, we believe that it has great potential to be a clinical modality in the future.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9609883 | PMC |
http://dx.doi.org/10.3390/mi13101626 | DOI Listing |
J Voice
July 2025
Departments of Radiology, Medicine and Roy J Carver Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa.
Objectives: MRI based vocal tract models have many applications in voice research and education. These models do not adequately capture bony structures (e.g.
View Article and Find Full Text PDFTransverse mode-locked (TML) beams exhibit high-speed beam scanning, which motivates a comparison with established beam deflection technologies, such as galvanometer and voice coil scanners. This study explores the hypothesis that TML beams can be regarded as high-speed equivalents of such periodically deflected beams. By analytically modeling the spatiotemporal properties of TML beams as well as experimentally examining periodically deflected beams, both their intensity and phase dynamics were assessed.
View Article and Find Full Text PDFSensors (Basel)
March 2025
State Key Laboratory of Tribology in Advanced Equipment, Tsinghua University, Beijing 100084, China.
In response to the accurate positioning issue for high-speed moving lens groups in rapid zoom optical lenses with voice coil motors (VCMs), we demonstrate a positioning system design based on tunnel magnetoresistance sensors. The equivalent magnetic charge method and finite element method (FEM) simulations were utilized to compute the magnetic field distribution of the magnetic grating encoder. Based on analytical computation, the optimal air gap between the sensor and magnetic grating is determined to be = 0.
View Article and Find Full Text PDFRev Sci Instrum
April 2025
Department of Aeronautics and Astronautics, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan.
Understanding the six-component thrust vector of an onboard propulsion system is essential for ensuring high-quality thrust and torque in advanced CubeSat missions, as propulsion systems may produce unintended thrust components such as side thrust, disturbance torques, or swirl torques. This paper proposes and demonstrates an elastic pendulum six-degree-of-freedom thrust stand designed to measure all thrust components of a propulsion system for CubeSats. Conventional six-degree-of-freedom thrust stands struggle to measure thrust in the mN class or lower due to the low thrust-to-weight ratio of propulsion systems.
View Article and Find Full Text PDFRev Sci Instrum
March 2025
State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
This paper presents the design of a parallel compliant pure rotational micropositioning stage driven by two voice coil motors aimed at achieving high precision and high responsiveness in pure rotation micropositioning. The stage consists of two leaf-spring based driving arms and a pair of symmetric isosceles trapezoidal mechanisms. The parallel structure of the stage can effectively enhance the system's stiffness and response speed.
View Article and Find Full Text PDF