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排序方式: 共有462条查询结果,搜索用时 62 毫秒
31.
Tateda M Omatsu T 《Journal of the Optical Society of America. A, Optics, image science, and vision》2003,20(2):342-346
We investigate a polarization state fixer that produces light with an arbitrary desired polarization state and constant power from an arbitrary elliptically polarized input light whose principal polarization axis fluctuates randomly. An example of such a device composed of a quarter-wave plate and a polarizer is proposed, and its characteristics at wavelengths of 633 nm and 1550 nm are demonstrated. We conclude that we cannot obtain a passive device that produces fixed-axis, linearly polarized light with a constant power level from an elliptically polarized light with a varying elliptical parameter. 相似文献
32.
Mitsuhiro Horade Sommawan Khumpuang Kazuya Fujioka Susumu Sugiyama 《Microsystem Technologies》2007,13(3-4):215-219
We have investigated and report in this paper the factors influencing the deformation caused by the dependence between the
absorbed X-ray energy on the resist and the shape of the absorber on the X-ray mask. Based on the measurement of errors that
occurred during the transferring process between the 2-D shape of mask pattern and the resulting wall of the fabricated 3-D
structure, we have developed newly useful graphical data on the absorbed X-ray energy, dosage, and shape of a microstructure.
As a result, it is being reported as a method for compensation for the deformed shape after the fabrication of a quadruplets-microneedle.
We have considered a number of factors affecting the deformation and finally realized that the effect of a dose–depth nonlinear
curve is the most possible cause. Without the compensation of the mask design, we could observe the deformed shapes of the
sloped sidewall on the exposed structures. Polymethylmethacrylate microneedle structures fabricated by X-ray lithography with
an additional plane-pattern to cross-section transfers technique are directly influenced by the absorber on the X-ray mask
pattern. The sidewall of the microneedle was improved by changing the mask pattern from a double right-triangular pattern
to a double semi-circular pattern, modeled by comparing the results from a mask-pattern and the actual structure. 相似文献
33.
Zhifeng Huang Takahiro Katayama Masako Kanai-Pak Jukai Maeda Yasuko Kitajima Mitsuhiro Nakamura 《Advanced Robotics》2013,27(19):1269-1285
We developed a robot patient for patient transfer training for simulating a patient’s performance during patient transfer and for enabling nurses to practice their nursing skills on it. To realize the robot patient, we focused on addressing the problems of designing its limb actions to enable it to respond to nurses’ operations. RC servos and electromagnetic brakes were installed in the joints to enable the robot to simulate a patient’s limb actions, such as embracing and remaining standing. To enable the robot to automatically respond to nurses’ operations, an identification method for these operations was developed that used voice commands and the features of the limbs’ posture measured by angle sensors installed in the robot’s joints. The robot patient’s performance was examined by a control test in which four experienced nursing teachers performed patient transfer with the robot patient and a human-simulated patient. The results revealed that the robot patient could successfully simulate the actions of a patient’s limbs according to the nursing teachers’ operations and that it is suitable for nursing skill training. 相似文献
34.
This paper describes the fabrication of poly(methyl methacrylate) (PMMA) microstructures with three-dimensional (3-D) sloped sidewalls using synchrotron-radiated (SR) deep X-ray lithography (DXRL). Here, the developer temperature was varied to produce variations in the inclination angle of the sloped sidewalls. We found that the PMMA sidewall inclination angle and height were controlled by the dosage, development time, and development temperature. When the development temperature was low, the inclination angle was nearly 0°, regardless of dosage amounts or exposure time. When the development temperature was high, microstructures with sloped sidewalls were fabricated; as the dosage amount and development time increased, the inclination angle increased. The ability to control the PMMA sidewall inclination angle suggests the application of this technique to microstructure fabrication technologies, such as 3-D microelectromechanical system (MEMS) device components, in which the inclination angle becomes the draft angle for moulding processes. 相似文献
35.
Kenji Fukuzawa Hiroaki Tsuji Satoshi Hamaoka Mitsuhiro Shikida Shintaro Itoh Hedong Zhang 《Microsystem Technologies》2013,19(9-10):1567-1572
It is important to understand friction force in micro/nano mechanical devices both at high sliding speed and with high lateral resolution. Dual-axis friction force microscopes that can provide high lateral resolution and accuracy have been proposed; however, the sliding speed is limited by the probe scan speed. While a micro mechanical probe (MMP) with an electrostatic actuator can overcome this problem, details of probe design have not been established yet. This paper presents the principle of the mechanical design for an MMP with high force sensitivity and sufficient drive force. The dimensions of the double cantilever beam control the spring constants, resonant frequencies, and drive force. The use of an actuated MMP enables accurate friction force microscopy at high sliding speeds, which is required for the design of micro/nano mechanical devices. 相似文献
36.
Brillouin frequency shift in a single-mode optical fiber has been measured as a function of tensile strain. The strain coefficient of normalized Brillouin frequency shift C≡(dv B/ d ϵ)/v B is found to be 4.4 for silica fibers. This result shows the potential of Brillouin spectroscopy to evaluate tensile strain in the fiber with the strain resolution of about 2×10-4. The origin of the large strain coefficient is discussed 相似文献
37.
38.
We report research on the development of a method of fabricating three-dimensional microstructures that uses synchrotron radiation light. Some research on three-dimensional processing methods using SR lithography has already been reported. They have involved techniques of applying exposure energy distributions to resist surfaces. Complicated energy distributions need to be applied to resist surfaces to fabricate arbitrary three-dimensional structures. However, we devised a new method that made it possible to fabricate arbitrary three-dimensional microstructures by using a mask with pattern created function. The advantages of this method are that it is suitable for rapid prototyping and it reduces the fabrication time and cost since it is not necessary to fabricate conventional photolithographic masks. Our research involved a basic experiment on this method of fabrication where we succeeded in fabricating a free-form surface by exposing it through an overlapping array of pixels that created a single aperture. Moreover, the pixel size could be made smaller than the aperture size by overlapping adjoining pixels. 相似文献
39.
Sachiro Kakinoki Makoto Kitamura Mitsuhiro Yuge Masakazu Furuta Masahito Oka Yoshiaki Hirano Kenji Kono Isao Kaetsu 《Polymer Bulletin》2007,58(2):393-400
Summary Poly(proline) and random copolypeptide composed of Pro and Ala residues were synthesized, and their solution properties and
molecular conformation were investigated. Aqueous solutions of the polypeptide were irradiated with γ-rays above the transition
temperature. It was shown that the transition temperature of the aqueous solution of the copolypeptide is influenced by Ala-residue
content and γ-ray irradiation. 相似文献
40.
A facile approach to the fabrication of ultrathin polymer films on a flat or curved substrate is presented. Polymers with unsaturated pendant groups were spin-coated on a photoinitiator tethered surface, which was then photoirradiated and washed with a solvent. The obtained films were uniform, smooth (Ra < 0.2 nm) and exhibited robustness toward solvents. The thickness of the films was determined by the molecular weight of the coated polymer and was not dependent on the initial spin-coated thickness. A mechanism for the formation of the ultrathin film and application to optical lenses is presented. 相似文献