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21.
Akinori Ohshita Masaaki Okuhara Chiharu Matsuya Koichi Hata Kazuo Iida 《Mikrochimica acta》2006,155(1-2):225-228
A new electron holographic method is presented to directly visualize pure phase objects such as electromagnetic microfields,
which is achieved by superposition of two kinds of electron holograms. The method is very simple and is twice as sensitive
as the conventional double-exposure electron holography and the four-electron-wave interference. Using this technique, an
electric field around a charged latex sphere and a magnetic field around a barium ferrite particle have been directly observed. 相似文献
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24.
K. Preston 《Angewandte Chemie (International ed. in English)》1972,11(4):279-287
The most recent branch of holography, acoustical holography employing acoustical radiation, presents a variety of new and highly interesting possible applications: Thus objects can be imaged in a turbid liquid medium (marine research); the technique can be used for non-destructive investigations of the internal structure of objects that are opaque to light (testing of materials) and is possibly also a potential tool for the three-dimensional imaging of biological structures (biomedical diagnosis). 相似文献
25.
JIN Xiang-qun ZHANG Jing-min XU Hui ZHOU Yan WANG Guang-shu ZHAO Yan-qiu ZHANG Han-qi 《高等学校化学研究》2006,22(2):185-188
Introduction Malignantdiseasesarecharacterizedbytheunreg ulatedgrowthoftransformedcells.Inrecentyears,dramaticinsightsintothemolecularmechanismsofthis phenomenonhavebeenachievedfrombasiccancerre search.Manycellularfunctionsareregulatedbychan gesingeneexpr… 相似文献
26.
With the availability of fast computers, inline electron holography, a technique for reconstructing both amplitude and phase of the electron wave function as scattered by the sample from a set of differently aberrated transmission electron microscopy images, is becoming increasingly quantitative. While focal series reconstruction from transmission electron microscopy images has already been practiced for at least 3 decades, existing approaches can only recover a relatively small band of spatial frequencies. Here I present a reconstruction scheme which is capable of reconstructing the electron wave function for a very large range of spatial frequencies, demonstrating its performance using simulated as well as experimental data. 相似文献
27.
A new asymmetric integral imaging (AII) system for real-time pickup and three-dimensional (3-D) display of far outdoor scenes based on dynamic-pixel-mapping (DPM) is proposed. DPM is a digital process to transform the elemental images captured with a lens array into the perspective-variant object images (POIs) whose structures are matched with those of display lenses, where the orders of pixels in each POI are reversely mapped, and then capture a set of virtual elemental images (EIs) at the specific depth planes from the back-propagated POIs. This DPM enables an asymmetrical use of pickup and display lens arrays, allowing the long-ranged pickup of far outdoor scenes and their resolution-enhanced 3-D reconstruction. Experiments with a pair of pickup and display lens arrays whose pitches and focal lengths are given by 7.5 mm, 30 mm and 1.2 mm, 8 mm, respectively, show that the effective pickup-range and resolution of the proposed system have been increased up to 6 m and 1600×1600 pixels, respectively, from 0.064 m and 480×480 pixels of the conventional systems employing the same pickup and display lens arrays. In addition, experiments with an implemented test bed confirms that the proposed system can provide real-time 3-D images in 25 frames per second. 相似文献
28.
The combined use of digital holographic microscopy and computer tomography, here named digital holographic micro-tomography, is used to examine the interior of transparent channels. The proposed method is used to identify internal obstacles inside of transparent troughs having slightly different refractive index. The method is based in the acquisition of a set of digital holograms of the specimen whereas it is axially rotated from 0° to 180°. The phase differences retrieved from the obtained holograms are the inputs to a computerised axial tomography procedure. The technique has been numerically modelled in order to find the optimal tomographic conditions and also to realise the minimum difference of refractive index the method could detect. The obtained results show the feasibility of the proposed method for the non-destructive evaluation of transparent micro-objects. 相似文献
29.
Ahmad A. SalaimehJeffrey J. Campion Belal Y. Gharaibeh Martin E. Evans Kozo Saito 《Infrared Physics & Technology》2012,55(1):170-172
We previously showed that infrared thermography (IRT) could be used to quantify viable Escherichiacoli, a representative gram-negative bacterium, in liquid growth media. Here, we evaluated the ability of IRT to enumerate a viable representative gram-positive organism, Staphylococcusaureus. We found that the energy content (EC) of the media was strongly positively correlated (r = 0.999) to measured viable counts of S.aureus ranging from 85 colony-forming units (CFU)/ml to ∼4 × 108 CFU/ml. The EC of S.aureus was ∼2-fold higher than that of E.coli at comparable cell concentrations suggesting that IRT may be used to distinguish genera. 相似文献
30.
A new resolution improving method of enhancing the interference stripes, which can achieve better reconstruction of the recorded object of infrared digital holography has been proposed in this paper. The experiment is conducted under near infrared illuminance. We create poor quality holograms with very low-resolution interference stripes and enhance it with our new method. The processed holograms have much higher-resolution interference stripes. This method is based on interpolation theory, and we make it works fast, stable and easy to apply. Both the forward and backward interpolation of the oriental and portrait direction of the source pixels have been calculated, and have been used to realize the final aim of resolution improvement. During the experiment, since the responsivity of the CCD is not satisfied with the illuminance laser, which is by design, we also give specific analysis on the experimental setup of our work to make sure the object information can be fully recorded by the optical setup but cannot be reconstructed because of the low-resolution and unobvious of the interference stripes. After the resolution improvement process of the original hologram, the object information can then be fully reconstructed, which is very clear in the paper. Figures and dataflow give evidence and demonstrate the good performance of our method. 相似文献