Arc 3D Research Articles

Three hundred sixty‐degree viewable linear grooves 3D display

AbstractWe proposed a linear grooves 3D display that can display 360° viewable 3D images by creating linear grooves that correspond to the viewpoint positions. In the conventional method, arc‐shaped grooves are drawn on a flat substrate of transparent film. However, depending on the viewing position, the image may be distorted. In addition, when a flat substrate is bent into a curved shape, the image is more affected than one observed in a flat shape. Furthermore, the conventional method of arc 3D display method cannot display a 3D image that corresponds to the viewpoint position. In this paper, we propose design and fabrication methods that reduce the image distortion for both flat and curved shapes. A 3D image displayed by the proposed method can change depending on the viewpoint position, and a natural 3D image with motion parallax can be observed. In the experiment, our proposed method fabricated a 360° 3D display by calculating the linear grooves and presented natural 3D images with smooth motion parallax.

Small field dosimetry employing the thermoluminescence technique using a 3D printed phantom

With the advent of new radiotherapy modalities, it has become necessary to apply relatively small fields that are dynamic or static. The use of these field sizes can cause uncertainty in dosimetry, requiring special attention in small field dosimetry. With these mentioned challenges, it is difficult to select a detector with good performance for dosimetry in small fields. TLDs have advantages because they have characteristics such as high spatial resolution and dose response, they offer a promising opportunity to measure the absorbed dose in a small field. The objective of this study is to evaluate the performance of CaSO4:Dy, LiF:Mg,Ti and μLiF:Mg,Ti thermoluminescent dosimeters for clinical photon beams in small field dosimetry using a 3D printed phantom. For clinical application the 6EX linear accelerator from Varian Medical System and the Multillif collimator from BrainLab were used. The 3D printed phantom was subjected to real treatment conditions. The dynamic arc 3D radiosurgery technique was adopted, with a dose of 7 Gy. To decrease statistical variation, the treatment simulation was repeated three times for each dosimeter. The results obtained demonstrated the viability of TLDs for clinical applications from photon beams to small fields. The values showed agreement in percentage terms below ±5% as recommended by the ICRU. The greatest percentage difference found was 1.2% (LiF:Mg;Ti) in relation to the planning system. All thermoluminescent dosimeters presented an uncertainty relatively low, with good stability and reproducibility in all measurements. The 3D printed phantom showed the possibility of achieving real treatment conditions.

Design of Arc 3D Printer Control System and Research on Slicing Algorithm

Design of Arc 3D Printer Control System and Research on Slicing Algorithm

Influence to Underwater Floating Image in Arc 3D Display by Material Difference of Arc 3D Substrates

Influence to Underwater Floating Image in Arc 3D Display by Material Difference of Arc 3D Substrates

Analysis of floating distance of arc 3D display with respect to inclination angle of substrate

Analysis of floating distance of arc 3D display with respect to inclination angle of substrate

3D-tomographic reconstruction of gliding arc plasma

This study presents three-dimensional (3D) emission tomography on gliding arc discharge for volumetric measurements of plasma luminosity fields. The 3D tomography of the plasma luminosity field enables quantification and characterization of 3D plasma features, which are not easily accessible in two-dimensional measurements. Simultaneous projections of the plasma discharge were imaged using multiple CMOS cameras, and an in-house developed tomographic method was used for the 3D reconstruction of the luminosity fields. Results show good field reconstruction quality and expected gliding arc topologies. Comparisons between arc 3D length and 2D projected length displayed that 2D measurements underestimated length by around 15% at the highest tested flow case. The mean 3D length initially increased with increasing air flow, while later decreasing at even higher flows. The standard deviation of 3D length increased with increasing flow. Arc curvature and overlap were generally seen to increase with higher flows in contrast to arc volume that was seen to decrease with increasing flow rates. This study aims to facilitate instantaneous 3D tomographic measurements of plasma luminosity fields to provide a detailed quantification of 3D characteristics and correlations of typical plasma features, thereby providing paths to remove line-of-sight effects and compensate for loss of information that may occur during two-dimensional measurements. The presented technique is applicable not only to gliding arcs but also to various other plasma systems.

Change in Long-Range Pop-up Distance of Arc 3D Display Due to Substrate Installation Angle

Change in Long-Range Pop-up Distance of Arc 3D Display Due to Substrate Installation Angle

Dosimetric Study Comparing 3D Conformal Radiotherapy (3D-CRT), Intensity Modulated Radiotherapy (IMRT) and Volumetric Modulated Arc Therapy (VMAT) in Hypofractionated One-Week Radiotherapy Regimen in Breast Cancer.

Introduction Recently, the one-week hypofractionated radiotherapy regimen (26 Gy in 5 fractions) for adjuvant breast radiotherapy has been shown to be non-inferior to other hypofractionated regimens (15-16 fractions). The aim of the present dosimetric study is to compare Intensity Modulated Radiotherapy (IMRT), Volumetric Modulated Arc Therapy (VMAT) and 3D Conformal Radiotherapy (3D-CRT) for a one-week hypofractionated radiotherapy regimen (26 Gy in 5 fractions) for adjuvant breast radiotherapy. Methods A total of 30 patients with histologically proven invasive carcinoma of the breast after breast conservation surgery (BCS) or modified radical mastectomy (MRM) were considered for in silico planning study. The dose prescription used was 26 Gy in 5 fractionsas used in the FAST Forward protocol. Targets were contoured according to standard guidelines. The heart, ipsilateral lung, and contralateral breast were contoured as organs at risk. Results Planning Target Volume (PTV) coverage:For IMRT, VMAT and 3D-CRT, respectively, the volumes that received at least 95% of the prescription dose (V95) were 95.7 ± 2.12, 92.47 ± 3.83, 90.87 ± 5.13; mean PTV doses (Dmean) were 26.1 ± 0.6, 25.7 ± 0.7, and 28 ± 4.39 (3D-CRT has higher Dmean compared to other techniques). Maximum PTV doses (Dmax) were 28.23 ± 0.72, 28.73 ± 0.64, and 29.8 ± 1.03. IMRT had a better V95 coverage and conformity index. Organs At Risk (OARs):The volumes that received at least 25% of the prescription dose (V25) of the heart were 3.41 ± 4.7, 1.8 ± 2.02 and 4.3 ± 6.98 in IMRT, VMAT and 3D-CRT, respectively. The volumetric (V25) comparison of heart dose in left-sided breast cancer was significantly different between VMAT and 3D-CRT (p=0.04, Wilcoxon signed-rank test). The volume that received at least 5% of the prescription dose (V5)was less than 25% in the 3D-CRT plan (12.55).For the ipsilateral lung, the V25 parameters were 19.53 ± 10.96, 23.93 ± 13.58 and 20.5 ± 12.32 in IMRT, VMAT and 3D-CRT, respectively. Conclusion From this study, we can conclude that IMRT and VMAT techniques are feasible and can achieve better dosimetric goals for target and OARs though minimizing the area achieving low dose remains to be a dosimetric concern for VMAT.

Analysis and fabrication for the dimensional expansion of arc 3D display to cone-shaped display

Analysis and fabrication for the dimensional expansion of arc 3D display to cone-shaped display

Microwave Technology for Hybrid Fabrication Processes

This paper aims to present how the microwave technology can be used in the development of hybrid joining and microjoining technologies for composites materials in order to increase productivity and quality of the welds. The paper is mainly focused on conceptualization of various types of hybrid processes by coupling a microwave beam with conventional thermal source such as arc welding, laser welding, 3D printing and others. The concepts presented in this paper will be completed with sensing solution for sensing and automation of the processes.

Dosimetric Comparison: Volumetric Modulated Arc Therapy (VMAT) and 3D Conformal Radiotherapy (3D-CRT) in High Grade Glioma Cancer—Experience of Casablanca Cancer Center at the Cheikh Khalifa International University Hospital

Background: Intensity Modulated Radiation Therapy (IMRT) is currently employed as a major arm of treatment in multiforme glioblastoma (GBM). The present study aimed to compare 3D-CRT with IMRT to assess tumor volume coverage and OAR sparing for the treatment of malignant gliomas. Materials and methods: We assessed 22 anonymized patients datasets with High Grade Glioblastoma who had undergone post-operative Intensity Modulated Radiotherapy (IMRT) and 3D Conformal Radiotherapy (3D-CRT), This study will compare and contrast treatment plans Rapidarc and 3D-CRT to determine which technology improves significantly dosimetric parameters. Results: Plans will be assessed by reviewing the coverage of the PTV using mean, maximum and minimum doses while the OAR doses will be compared using the maximal doses for each, as set out in the QUANTEC dose limits. Conclusion: The use of IMRT seems a superior technique as compared to 3D-CRT for the treatment of malignant gliomas having the potential to increase the dose to the PTV while sparing OARs optimally.

Dosimetric Comparison: Volumetric Modulated Arc Therapy (VMAT) and 3d Conformal Radiotherapy (3d-CRT) in High Grade Glioma Cancer Experience of Casablanca Cancer Center at the Cheikh Khalifa International University Hospital

Background: Intensity Modulated Radiation Therapy (IMRT) is currently employed as a major arm of treatment in multiforme glioblastoma (GBM). The present study aimed to compare 3D-CRT with IMRT to assess tumor volume coverage and OAR sparing for treatment of malignant gliomas. Materials and Methods: We assessed 22 anonymized patients datasets with High Grade Glioblastoma who had undergone post-operative Intensity Modulated Radiotherapy (IMRT) and 3D Conformal Radiotherapy (3D-CRT), This study will compare and contrast treatment plans Rapidarc and 3D-CRT to determine which technique improves significantly dosimetric parameters. Results: Plans will be assessed by reviewing the coverage of the PTV using mean, maximum and minimum doses while the OAR doses will be compared using the maximal doses for each, as set out in the QUANTEC dose limits. Conclusion: The use of IMRT seems a superior technique as compared to 3D-CRT for the treatment of malignant gliomas having the potential to increase dose to the PTV while sparing OARs optimally

Theoretical and Experimental Perceived Depths in Arc 3D Displays: On/Off Switching Using Liquid-Crystal Active Devices

In this article, we obtain precise theoretical expressions and various experimental dependences of the perceived depth in an arc 3D display and find that they coincide. We also propose two liquid-crystal (LC) active devices that can switch arc 3D images on and off by changing either the amplitude or frequency of a high applied voltage and clarify their main characteristics. The perceived depth in an arc 3D display can be increased by increasing the arc radius and/or adjusting the illumination angle so that it approaches the viewing angle vertically. The perceived depth remains unchanged even when the observer position changes in the horizontal and/or depth directions, resulting in a continuous motion parallax.

Stereotactic radiotherapy for small and very small tumours (≤1 to ≤3 cc): evaluation of the influence of volumetric-modulated arc therapy in comparison to dynamic conformal arc therapy and 3D conformal radiotherapy as a function of flattened and unflattened beam models

AbstractPurpose:The objective of this article is to evaluate the dosimetric efficacy of volumetric modulated arc therapy (VMAT) in comparison to dynamic conformal arc therapy (DCAT) and 3D conformal radiotherapy (3DCRT) for very small volume (≤1 cc) and small volume (≤3 cc) tumours for flattened (FF) and unflattened (FFF) 6 MV beams.Materials and methods:A total of 21 patients who were treated with single-fraction stereotactic radiosurgery, using either VMAT, DCAT or 3DCRT, were included in this study. The volume categorisation was seven patients each in <1, 1–2 and 2–3 cc volume. The treatment was planned with 6 MV FF and FFF beams using three different techniques: VMAT/Rapid Arc (RA) (RA_FF and RA_FFF), dynamic conformal arc therapy (DCA_FF and DCA_FFF) and 3DCRT (Static_FF and Static_FFF). Plans were evaluated for target coverage (V100%), conformity index, homogeneity index, dose gradient for 50% dose fall-off, total MU and MU/dose ratio [intensity-modulated radiotherapy (IMRT) factor], normal brain receiving >12 Gy dose, dose to the organ at risk (OAR), beam ON time and dose received by 12 cc of the brain.Result:The average target coverage for all plans, all tumour volumes (TVs) and delivery techniques is 96·4 ± 4·5 (range 95·7 ± 6·1–97·5 ± 2·9%). The conformity index averaged over all volume ranges <1, 2, 3 cc> varies between 0·55 ± 0·08 and 0·68 ± 0·04 with minimum and maximum being exhibited by DCA_FFF for 1 cc and Static_FFF/RA_FFF for 3 cc tumours, respectively. Mean IMRT factor averaged over all volume ranges for RA_FF, DCA_FF and Static_FF are 3·5 ± 0·8, 2·0 ± 0·2 and 2·0 ± 0·2, respectively; 50% dose fall-off gradient varies in the range of 0·33–0·42, 0·35–0·40 and 0·38–0·45 for 1, 2 and 3 cc tumours, respectively.Conclusion:This study establishes the equivalence between the FF and FFF beam models and different delivery techniques for stereotactic radiosurgery in small TVs in the range of ≤1 to ≤3 cc. Dose conformity, heterogeneity, dose fall-off characteristics and OAR doses show no or very little variation. FFF could offer only limited time advantage due to excess dose rate over an FF beam.

Perceived Depth in Arc 3D Display Can Penetrate into Behind Real Object by Moving Arc 3D Images in Contrast to Unpenetrated Perceived Depth in Stereoscopic Display

Proceedings of the International Display Workshops Volume 26 (IDW '19),Perceived Depth in Arc 3D Display Can Penetrate into Behind Real Object by Moving Arc 3D Images in Contrast to Unpenetrated Perceived Depth in Stereoscopic Display

Perceived Depth in Arc 3D Display Can Penetrate into Behind Real Object by Moving Arc 3D Images in Contrast to Unpenetrated Perceived Depth in Stereoscopic Display

Perceived Depth in Arc 3D Display Can Penetrate into Behind Real Object by Moving Arc 3D Images in Contrast to Unpenetrated Perceived Depth in Stereoscopic Display

Monocular Perceived Depth Improvement Using Motion Parallax in Arc 3D Display and Dependence on Motion Cycle Time

Monocular Perceived Depth Improvement Using Motion Parallax in Arc 3D Display and Dependence on Motion Cycle Time

Monocular Perceived Depth Improvement Using Motion Parallax in Arc 3D Display and Dependence on Motion Cycle Time

Monocular Perceived Depth Improvement Using Motion Parallax in Arc 3D Display and Dependence on Motion Cycle Time

A New 3D Image Switching Method in Arc 3D Display by Selecting Desired Arcs in Arc Array by Projectors with Different Illumination Angles for Changing Depths

Proceedings of the International Display Workshops Volume 26 (IDW '19),A New 3D Image Switching Method in Arc 3D Display by Selecting Desired Arcs in Arc Array by Projectors with Different Illumination Angles for Changing Depths

A New 3D Image Switching Method in Arc 3D Display by Selecting Desired Arcs in Arc Array by Projectors with Different Illumination Angles for Changing Depths

A New 3D Image Switching Method in Arc 3D Display by Selecting Desired Arcs in Arc Array by Projectors with Different Illumination Angles for Changing Depths