scholarly journals Stereoscopic Calculation Model Based on Fixational Eye Movements

2021 ◽  
Author(s):  
Norio Tagawa

Fixational eye movement is an essential function for watching things using the retina, which has the property of responding only to changes in incident light. However, since the rotation of the eyeball causes the translational movement of the crystalline lens, it is possible in principle to recover the depth of the object from the moving image obtained in this way. We have proposed two types of depth restoration methods based on fixation tremor; differential-type method and integral-type method. The first is based on the change in image brightness between frames, and the latter is based on image blurring due to movement. In this chapter, we introduce them and explain the simulations and experiments performed to verify their operation.

Author(s):  
O. T. Inal ◽  
L. E. Murr

When sharp metal filaments of W, Fe, Nb or Ta are observed in the field-ion microscope (FIM), their appearance is differentiated primarily by variations in regional brightness. This regional brightness, particularly prominent at liquid nitrogen temperature has been attributed in the main to chemical specificity which manifests itself in a paricular array of surface-atom electron-orbital configurations.Recently, anomalous image brightness and streaks in both fcc and bee materials observed in the FIM have been shown to be the result of surface asperities and related topographic features which arise by the unsystematic etching of the emission-tip end forms.


2018 ◽  
Vol 106 (6) ◽  
pp. 603 ◽  
Author(s):  
Bendaoud Mebarek ◽  
Mourad Keddam

In this paper, we develop a boronizing process simulation model based on fuzzy neural network (FNN) approach for estimating the thickness of the FeB and Fe2B layers. The model represents a synthesis of two artificial intelligence techniques; the fuzzy logic and the neural network. Characteristics of the fuzzy neural network approach for the modelling of boronizing process are presented in this study. In order to validate the results of our calculation model, we have used the learning base of experimental data of the powder-pack boronizing of Fe-15Cr alloy in the temperature range from 800 to 1050 °C and for a treatment time ranging from 0.5 to 12 h. The obtained results show that it is possible to estimate the influence of different process parameters. Comparing the results obtained by the artificial neural network to experimental data, the average error generated from the fuzzy neural network was 3% for the FeB layer and 3.5% for the Fe2B layer. The results obtained from the fuzzy neural network approach are in agreement with the experimental data. Finally, the utilization of fuzzy neural network approach is well adapted for the boronizing kinetics of Fe-15Cr alloy.


2011 ◽  
Vol 131 (12) ◽  
pp. 1017-1023 ◽  
Author(s):  
Norihito Yanagita ◽  
Tatsuro Kato ◽  
Toshiaki Rokunohe ◽  
Takeshi Iwata ◽  
Hiroki Kojima ◽  
...  

2020 ◽  
Vol 2020 (2) ◽  
pp. 100-1-100-6
Author(s):  
Takuya Omura ◽  
Hayato Watanabe ◽  
Naoto Okaichi ◽  
Hisayuki Sasaki ◽  
Masahiro Kawakita

We enhanced the resolution characteristics of a threedimensional (3D) image using time-division multiplexing methods in a full-parallax multi-view 3D display. A time-division light-ray shifting (TDLS) method is proposed that uses two polarization gratings (PGs). As PG changes the diffraction direction of light rays according to the polarization state of the incident light, this method can shift light rays approximately 7 mm in a diagonal direction by switching the polarization state of incident light and adjusting the distance between the PGs. We verified the effect on the characteristics of 3D images based on the extent of the shift. As a result, the resolution of a 3D image with depth is improved by shifting half a pitch of a multi-view image using the TDLS method, and the resolution of the image displayed near the screen is improved by shifting half a pixel of each viewpoint image with a wobbling method. These methods can easily enhance 3D characteristics with a small number of projectors.


Author(s):  
V.Y. Markevich ◽  
◽  
T.A. Imshenetskaya ◽  
O.A. Yarmak ◽  
◽  
...  

Purpose. To study the effectiveness of extrascleral filling (ESF) using endoillumination in the surgical treatment of patients with primary rhegmatogenous retinal detachment (RRD). Material and methods. The material for the study was the data of a comprehensive clinical examination and surgical treatment by ESF method using endoillumination in 17 patients (17 eyes) with RRD. In 7 cases (41%), the macular area was involved in the detachment process. In 5 cases (29.4%), local scleral filling was performed. In the remaining 12 cases (70.6%), the local ESF was supplemented with a circling silicone element. Surgical intervention was supplemented by transscleral drainage of subretinal fluid (SRF) in 10 cases (59%) and pneumatic retinopexy with SF6 gas 50% in 8 cases (48%). Results. In the general group of patients, best corrected visual acuity (BCVA) increased from 0.35 to 0.46. In the subgroup of patients with a detached macular area, the positive dynamics is more pronounced, BCVA increased from 0.1 to 0.28. The progression of proliferative vitreoretinopathy caused the recurrence of retinal detachment in two patients (11.8%). Recurrences were diagnosed after 3 and 5 months, respectively. In both cases, a vitrectomy with tamponade of the vitreous cavity with silicone oil 5000 Cst was performed. The percentage of successful anatomical outcome after the first operation in our study was 82%. The percentage of successful achievement of the final anatomical result was 94%. In two cases, additional injection of SF6 gas into the vitreous cavity was required. Conclusion. This type of surgical treatment is an effective method of surgical treatment of patients with RRD. In our study, the successful anatomical outcome after the first operation was recorded in 82% of patients, which correlates with the data of the authors who also used this method (83–92%). Surgeons who performed surgical treatment using this technique in our study note improved workplace ergonomics when visualizing the fundus using an operating microscope and endoillumination compared with indirect ophthalmoscopy. Other teams of authors came to this conclusion as well. In our study, there were no complications associated with the introduction of a light pipe into the vitreous cavity (iatrogenic crystalline lens injury, endophthalmitis), which indicates the safety of this type of surgical treatment.


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