基于激光捕捉微粒子实现微细加工的新概念研究

利用高倍显微物镜所聚合的激光在粒子表面所产生的辐射压可捕捉几个微米大小的高强度粒子,这些被捕捉的粒子在激光驱动下,能移动、转动及振动,可成为微加工工具,在被加工表面上形成微米乃至纳米级的表面微细切削。基于几何光学模型对捕捉进行数字仿真,所设计形状粒子的加工力最大可达到mW/N101.210-。     

Applications of a microlens array and a photomask to the laser microfabrication of a periodic photopolymer rod array

We report the simultaneous multipoint fabrication of polymer rods by the femtosecond laser processing of a negative photoresist using a microlens array (MLA). The rods were periodically arranged in the form of an array corresponding to the MLA and free-standing on a glass substrate. The use of a photomask enabled us to define the contour of the rod array. Furthermore, sample translation techniques were demonstrated for the effective fabrication of large-area structures.     

Prism-type holographic optical element design and verification for the blue-light small-form-factor optical pickup head

This paper presents the prism-type holographic optical element (PT-HOE) design for a small-form-factor (SFF) optical pickup head (OPH). The surface of the PT-HOE was simulated by three steps of optimization and generated by binary optics. Its grating pattern was fabricated on the inclined plane of a microprism by using the standard photolithography and specific dicing procedures. The optical characteristics of the device were verified. Based on the virtual image method, the SFF-OPH with the device was assembled and realized.     

Focused ion beams for microfabrication

Focused ion beam (FIB) techniques are commonly used in microelectronics for prototyping, failure analysis and process control. With the growing interest in MEMS (micro-electro-mechanical systems) the importance of FIB techniques in this field has to be established. For the FIB to be considered for production, the milling time is crucial. Using as an example the fabrication of a microaccelerometer structure the authors show there is scope for the FIB in the prototyping and production of micromechanical structures, leading to novel sensors     

Capillary electrophoresis micro X-ray fluorescence: a tool for benchtop elemental analysis

A new tool was developed for separation and elemental detection by interfacing a simple capillary electrophoresis (CE) apparatus, constructed using a thin-walled fused-silica capillary, with a benchtop energy-dispersive micro X-ray fluorescence (MXRF) system. X-ray excitation and detection of the separated analytes was done using an EDAX Eagle II micro X-ray fluorescence system equipped with a polycapillary Rh target excitation source and a SiLi detector. It was demonstrated that this prototype system could be used for the separation and detection of species containing two different metals from one another, specifically Cu and Co. Free Co could also be separated from Co bound to cyanocobalamin (vitamin B-12). Two organic compounds were also separated from one another, a large biological protein, ferritin, from a small biological organic, cyanocobalamin. Preliminary average detection limits obtained on this system were on the order of 10(-)(4) M and compared favorably to those reported for the similar technique of CE-synchrotron XRF. CEMXRF allows for nondestructive, simultaneous, on-line, benchtop elemental analysis for chemical speciation applications.     

Axial superresolution of two-photon microfabrication

An axial superresolution diffraction theory is developed in a two-photon microfabrication system. This method can improve the axial superresolution of the two-photon microfabrication system. A theoretical analysis of the photosensitive resin is discussed based on the exciting power and the concentration of free radical theory. Simulated results of the two-photon microfabrication verify the method and show that it can provide insight into the microfabrication system.     

Triple-wavelength optical pickup head designs for compact disk,digital versatile disk and high-density digital versatile disk devices

We present a triple-wavelength design for a compact optical pickup head which uses two rhomboid prisms in parallel with three laser diodes. The design can be used for compact disk, digital versatile disk and high-density digital versatile disk devices. The specific prism lens used decreases the geometrical size and reduces the total number of optical components. The trade-off between tolerance and fabrication is also presented.     

Polysilicon-based strain transducer for pressure pickup

Translated from Izmeritel'naya Tekhnika, No. 5, pp. 19–21, May, 1991.     

Instruments and methods for microfabrication by laser-controlled chemistry

The two principal methods of patterning of solid-state electronics via laser-controlled surface reactions, (1) laser direct writing and (2) laser projection, are briefly reviewed with an emphasis on the current instruments and sources.     

Real-time pickup method for a three-dimensional image based on integral photography

We studied integral photography (IP), which creates three-dimensional autostereoscopic images. In particular we studied the possibility of a new method that uses a television camera to shoot directly numerous real images produced by a lens array. Unlike the conventional IP method in which the film is placed immediately behind a lens array, this method employs a television camera, which enables us to shoot moving pictures. Of a number of factors affecting the process of image pickup, we examined some optical factors and compared them with those obtained by the conventional IP method. The results show that with this new direct pickup method that uses a television camera, we can obtain an IP image like those obtained by using the conventional IP method. Further, we conducted an experiment with an high-definition TV camera, confirming the production of an autostereoscopic image by using a display device that combines a liquid-crystal panel and pinholes.     

Fast one-dimensional profilometer with a compact disc pickup

The use of compact disc (CD) pickups in optical profilometry is a well-established practice. The instruments currently available on the market are, however, expensive both to purchase and to maintain. This expense is mainly due to the high cost of the scanning system, and it makes the use of low-cost pickups fruitless. Moreover, translation stages are bulky, slow, and in most applications neither necessary nor desirable. We present a one-dimensional profilometer, which uses a CD pickup as both the sensor and the actuator. Beam scanning of the sample is in fact performed by the objective lens tracking motor. The device is cheap, fast, compact, light, and a valuable solution for fluid and hard-to-access surface profiling.     

Laser Doppler velocimetry with a compact disc pickup

A laser Doppler velocimeter employing a compact disc pickup for both fringe projection and signal detection is described. The spectrum of the recorded signal gives the information about the speed of the object. The device takes advantage of the Talbot effect to project the grating contained in the pickup onto a moving target, so that no imaging system is required. The peculiar imaging technique allows for the exploitation of several optical configurations and permits the manipulation of the intensity profile of the projected grating. The instrument was used to measure the velocity of dust particles on a solid substrate in the 1-m/s range but could also find an application to the study of liquid flow.     

Correlation optical velocimetry with a compact disk pickup

The compact disk pickup is a consumer electronics component that can be purchased for a low price owing to the great number of units produced every year. A typical three-beam head contains, enclosed in a tiny case, a quite complete sample of what can be found in an optoelectronics laboratory: a coherent source, a grating, a polarizing beam splitter, a fourth-wave plate, solid-state detectors, and much more. Exploiting the unique features of such a device for scientific aims is intriguing from many points of view. We present a straightforward application of a compact disk pickup to optical correlation velocimetry and show how a rather complicated discrete setup can be replaced successfully by this highly integrated component.     

Differential resonance-impedance radio pickup with a pulsed bias voltage for plasma diagnostics

A differential radio-frequency pickup with a pulsed bias voltage when investigating the physical characteristics of laboratory and ionospheric plasma of the Earth and planets is considered. It is shown that the use of this pickup simplifies the interpretation of the high-frequency measured signal and gives reliable experimental data.Translated from Izmeritel'naya Tekhnika, No. 9, pp. 55–57, September, 1995.     

Manipulation and observation of Ag photodoping patterns in GeS2 amorphous films by a dual functional laser scanning microfabrication/microscope system

The photodoping phenomenon of Ag is one of the light-induced phenomena in GeS(2) amorphous chalcogenide films. It has potential as a process for fabricating photonic structures, such as waveguides and micro-optics, but its fabrication method is still under research. A dual functional laser scanning system integrating microfabrication and microscope systems was developed. In situ nanoscale fabrication by a UV laser effective for photodoping, and observation by a VIS wavelength laser, which does not affect the material, were demonstrated under same setup in one system. Several fine doped patterns were fabricated and the optical performances were evaluated. These results give the feasibility of forming various photonic structures.     

Transformer alternating electric field pickup for marine research

The possibility of increasing (by 1.5 to 3 times) the conversion coefficient of a marine transformer alternating electric field pickup by changing its construction is demonstrated. Translated from Izmeritel'naya Tekhnika, No. 8, pp. 58–60, August, 1997.     

Integrated optical pickup system for axial dual focus

We propose an optical pickup that acquires data from both layers of a dual-layer digital versatile disk simultaneously. An adaptive optical element that uses liquid crystals creates two axial foci separated by a spacing of 55 mum, which is the distance between the two layers. The spacing between the foci can be varied by the adaptive element. The separation of the reflected light into TE and TM polarized light, corresponding to each of the layers, is made by dielectric gratings that are characterized by high aspect ratios. Electron-beam lithography and reactive ion etching techniques were used to produce the submicrometer structures. All fabricated elements were assembled in a pickup system, whose properties were measured.     

混合集成型光学拾音器的设计与制作

通过混合集成型结构光学拾音器的光学设计和芯片设计，制作了包含微光学棱镜，光电探测器和信号放大电路的混合集成型光学拾音器。经过测试，发现有较好的信号输出特性，表明混合集成型光学拾音器已基本研制成功。     

Modelling of the flow around a high-altitude ion concentration pickup

The results are presented for a study of the flow structure in the supersonic flow of air around a cylindrical body with an open and a blocked inner channel under the conditions of altitudes of 54–67 km. The studies were conducted on a low-density wind tunnel using the electron beam method of measurements.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 25, No. 1, pp. 111–115, July, 1973.