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Journal articles on the topic 'Free-form lens'

Author: Grafiati

Published: 4 June 2021

Last updated: 12 February 2022

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1

Rubinstein, Jacob, and Gershon Wolansky. "Intensity control with a free-form lens." Journal of the Optical Society of America A 24, no. 2 (February 1, 2007): 463. http://dx.doi.org/10.1364/josaa.24.000463.

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2

Wang, Lin, Keyuan Qian, and Yi Luo. "Discontinuous free-form lens design for prescribed irradiance." Applied Optics 46, no. 18 (May 31, 2007): 3716. http://dx.doi.org/10.1364/ao.46.003716.

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3

SUN Li-wei, 孙理伟, 金尚忠 JIN Shang-zhong, and 岑松原 CEN Song-yuan. "Free-form Micro-lens Design for Solid State Lighting." ACTA PHOTONICA SINICA 39, no. 5 (2010): 860–65. http://dx.doi.org/10.3788/gzxb20103905.0860.

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4

Xu, CY, and HB Cheng. "A free-form side-emitting lens for airfield lighting." Lighting Research & Technology 50, no. 6 (April 14, 2017): 937–51. http://dx.doi.org/10.1177/1477153517702695.

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Side-emitting lenses are essential devices in some special lighting fields. Two types of side-emitting lenses with refractive and total reflective free-form surfaces are introduced. The principles of geometric optics and non-imaging optics are adopted to construct the free-form surfaces without complex mapping or a differential iteration process. As an example, an elevated taxiway edge light is designed for airfield lighting. A side-emitting lens with two sawtooth additions on top is designed to meet the luminous intensity distribution required by the US Federal Aviation Administration (FAA). An analysis is carried out to determine tolerance limits during manufacture and installation. Computer simulation results show that a side-emitting efficiency of 85.4% is achieved for a Cree XP-E LED. The light distribution of this elevated taxiway edge light complies with the FAA regulations.

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5

Miñano, Juan C., Pablo Benítez, Pablo Zamora, Marina Buljan, Rubén Mohedano, and Asunción Santamaría. "Free-form optics for Fresnel-lens-based photovoltaic concentrators." Optics Express 21, S3 (April 22, 2013): A494. http://dx.doi.org/10.1364/oe.21.00a494.

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6

Lin, Chi-Feng, Yu-Bin Fang, and Wei-Chih Su. "Design of LED Free-form Lens for Sensor Systems." Sensors and Materials 32, no. 6 (June 30, 2020): 2177. http://dx.doi.org/10.18494/sam.2020.2905.

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7

LUO Xiao-xia, 罗晓霞, 刘华 LIU Hua, 卢振武 LU Zhen-wu, 荆雷 JING Lei, 姜洋 JIANG Yang, and 辛迪 Xin Di. "Automated Optimization of Free-form Surface Lens for LED Collimation." ACTA PHOTONICA SINICA 40, no. 9 (2011): 1351–55. http://dx.doi.org/10.3788/gzxb20114009.1351.

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8

Lubini, M., M. Sereno, J. Coles, Ph Jetzer, and P. Saha. "Cosmological parameter determination in free-form strong gravitational lens modelling." Monthly Notices of the Royal Astronomical Society 437, no. 3 (November 30, 2013): 2461–70. http://dx.doi.org/10.1093/mnras/stt2057.

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9

Tsai, Chung-Yu. "Free-form surface design method for a collimator TIR lens." Journal of the Optical Society of America A 33, no. 4 (March 31, 2016): 785. http://dx.doi.org/10.1364/josaa.33.000785.

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10

Duerr, Fabian, Pablo Benítez, Juan C. Miñano, Youri Meuret, and Hugo Thienpont. "Analytic free-form lens design in 3D: coupling three ray sets using two lens surfaces." Optics Express 20, no. 10 (April 25, 2012): 10839. http://dx.doi.org/10.1364/oe.20.010839.

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11

Yi, Ding, Shi Yan, Wang Xiaofeng, Chen Liang, and Jin Shangzhong. "Coupling lens design of fiber lighting based on free-form surface." Journal of Applied Optics 38, no. 4 (2017): 633–38. http://dx.doi.org/10.5768/jao201738.0408001.

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12

Ma, Yufei, Hang Zhang, Zeyu Su, Yu He, Liang Xu, Xu Liu, and Haifeng Li. "Hybrid method of free-form lens design for arbitrary illumination target." Applied Optics 54, no. 14 (May 7, 2015): 4503. http://dx.doi.org/10.1364/ao.54.004503.

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13

Aslanov, Emil, Leonid L. Doskolovich, and Mikhail A. Moiseev. "Thin LED collimator with free-form lens array for illumination applications." Applied Optics 51, no. 30 (October 12, 2012): 7200. http://dx.doi.org/10.1364/ao.51.007200.

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14

Han, Susan C., Andrew D. Graham, and Meng C. Lin. "Clinical Assessment of a Customized Free-Form Progressive Add Lens Spectacle." Optometry and Vision Science 88, no. 2 (February 2011): 234–43. http://dx.doi.org/10.1097/opx.0b013e31820846ac.

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15

Le, Neng-you, Zhi-wei Shi, and Xin-gang Shi. "Design of LED free form lens based on improved mesh method." Optik 183 (April 2019): 565–70. http://dx.doi.org/10.1016/j.ijleo.2019.02.005.

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16

Liu Zhanyu, 刘展宇, 王沛沛 Wang Peipei, 金志樑 Jin Zhiliang, 王海洋 Wang Haiyang, and 熊大曦 Xiong Daxi. "Free-Form Lens Design for LED Fishing Lamp with Stable Illumination." Acta Optica Sinica 41, no. 5 (2021): 0522003. http://dx.doi.org/10.3788/aos202141.0522003.

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17

Ghosh, Agniva, Liliya L. R. Williams, and Jori Liesenborgs. "Free-form grale lens inversion of galaxy clusters with up to 1000 multiple images." Monthly Notices of the Royal Astronomical Society 494, no. 3 (April 9, 2020): 3998–4014. http://dx.doi.org/10.1093/mnras/staa962.

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ABSTRACT In the near future, ultra deep observations of galaxy clusters with Hubble Space Telescope or James Webb Space Telescope will uncover 300–1000 lensed multiple images, increasing the current count per cluster by up to an order of magnitude. This will further refine our view of clusters, leading to a more accurate and precise mapping of the total and dark matter distribution in clusters, and enabling a better understanding of background galaxy population and their luminosity functions. However, to effectively use that many images as input to lens inversion will require a re-evaluation of, and possibly upgrades to the existing methods. In this paper, we scrutinize the performance of the free-form lens inversion method grale in the regime of 150–1000 input images, using synthetic massive galaxy clusters. Our results show that with an increasing number of input images, grale produces improved reconstructed mass distributions, with the fraction of the lens plane recovered at better than $10{{\ \rm per\ cent}}$ accuracy increasing from $40\!-\!50{{\ \rm per\ cent}}$ for ∼150 images to $65{{\ \rm per\ cent}}$ for ∼1000 images. The reconstructed time delays imply a more precise measurement of H0, with $\lesssim 1{{\ \rm per\ cent}}$ bias. While the fidelity of the reconstruction improves with the increasing number of multiple images used as model constraints, ∼150 to ∼1000, the lens plane rms deteriorates from ∼0.11 to ∼0.28 arcsec. Since lens plane rms is not necessarily the best indicator of the quality of the mass reconstructions, looking for an alternative indicator is warranted.

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18

Sun, Yan Jun, Yan Bing Leng, Zhe Chen, and Lian He Dong. "Study on Optical Property of Fabricating Free-Form Micro-Optical Element by Varying Dose Exposure Method." Key Engineering Materials 552 (May 2013): 131–36. http://dx.doi.org/10.4028/www.scientific.net/kem.552.131.

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Free-form lens is a special element with non-rotating body and aspheric structure. The surface can’t be expressed by stationary analytic formula, and generally it expressed by discrete list point. Free-form lens can distribute light intensity freely,and control light angle、optical path difference etc. Specific light spot is formed in illumination surface, meanwhile the light energy utilization ratio is improved greatly. There are two kinds of methods about Free-form fabrication, and the first kind of method is that free-form is grinded by a small grinding head ,which is controlled by computer; its disadvantage is low precision、high waster rate，especially for optical material; The second kind fabricating method is that multi-degree-of-freedom single-point diamond turning equipment; its disadvantage is that plenty of sub-micron crack formed when brittle material fabricated. In addition, micro-lens array element can’t be fabricated by the two kinds of methods. In allusion to the feature of free-form without stationary analytic formula ,which varying dose exposure lithography method for free-form micro-optical element is presented for free-form micro-lens and array. The method is from the theory that the relation between different exposure energy and different developing depth, adopting laser direct writing equipment free-form photoresist structure is formed in material surface, then the free-form photoresist structure is transfered on the substrate by ion etching method. Any surface figure can be fabricated by controlling every point laser energy for this method, and surface roughness can’t be effected because ion etching belongs to nanofabrication. In this paper, that low Distribution of light amplitude and relation of between exposure energy and exposure time was analysised on base of optical propagation theory and mathematical model of light distribution law was built and simulated by computer program.The results indicate that light energy distributes in accordance with specific law; the exposure depth increases with exposure time. The experiment of exposure and developing finished, used the BOL-500 laser direct writing system in Changchun University of Science and technology,american Futurrex62A photoresist, 412nn He-Ne laser device, 5‰NaOH developing solution. The experimental data coincide with simulation result via comparative analysis. Meanwhile，a set of free-form micro-lens array testing system was established and focal spot shape,energy distribution,focal distance,F parameter were tested about the micro-lens array.

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19

YU Jing, 禹静, 蒋威炜 JIANG Wei-wei, and 沈小燕 SHEN Xiao-yan. "Wavefront Aberration Beam Expansion-shrinkage Splicing Technology of Free-form Surface Lens." ACTA PHOTONICA SINICA 48, no. 8 (2019): 822002. http://dx.doi.org/10.3788/gzxb20194808.0822002.

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20

Gui Li, 桂立, 孙秀辉 Sun Xiuhui, 尹韶云 Yin Shaoyun, 杜春雷 Du Chunlei, and 向阳 Xiang Yang. "Modeling Error Analysis and Compensation Design for Free-Form Uniform Illumination Lens." Acta Optica Sinica 35, no. 10 (2015): 1022008. http://dx.doi.org/10.3788/aos201535.1022008.

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21

Yen, Jyh Chyang, Jin Jia Chen, and Kuang Lung Huang. "Optimization and Analysis of Alvarez Lens." Advanced Materials Research 1079-1080 (December 2014): 889–94. http://dx.doi.org/10.4028/www.scientific.net/amr.1079-1080.889.

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Alvarez lens is one of the free form lens designs. After optimized, the focusing distance curve of Alvarez lens keeps smoothly when Δd increased. We also found the effects of the affective factors, and the good performances of geometric image and illumination surface analysis.

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22

Ju Yuan, 句源, 赵春竹 Zhao Chunzhu, 朴明旭 Piao Mingxu, 郭玉 Guo Yu, 顾姗姗 Gu Shanshan, and 郑汉青 Zheng Hanqing. "基于自由曲面透镜阵列的共形整流罩动态像差校正." Acta Optica Sinica 41, no. 9 (2021): 0922002. http://dx.doi.org/10.3788/aos202141.0922002.

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23

FUKUTA, Masahiko. "908 Study for Making technology of Lens-array mold on Free-form Surface." Proceedings of the Materials and processing conference 2012.20 (2012): _908–1_—_908–3_. http://dx.doi.org/10.1299/jsmemp.2012.20._908-1_.

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24

Yang, Bo, Jukka Tapani Mäkinen, Mika Aikio, Guofan Jin, and Yongtian Wang. "Free-form lens design for wide-angle imaging with an equidistance projection scheme." Optik 120, no. 2 (January 2009): 74–78. http://dx.doi.org/10.1016/j.ijleo.2007.05.008.

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25

Wagner, Jenny, and Liliya L. R. Williams. "Model-independent and model-based local lensing properties of B0128+437 from resolved quasar images." Astronomy & Astrophysics 635 (March 2020): A86. http://dx.doi.org/10.1051/0004-6361/201936628.

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The galaxy-scale gravitational lens B0128+437 generates a quadrupole-image configuration of a background quasar that shows milli-arcsecond-scale subcomponents in the multiple images observed with VLBI. As this multiple-image configuration including the subcomponents has eluded a simple parametric lens-model characterisation so far, we determined local lens properties at the positions of the multiple images with our model-independent approach. Using PixeLens, we also succeeded in setting up a global free-form mass density reconstruction, including all subcomponents as constraints. We compared the model-independent local lens properties with those obtained by PixeLens and those obtained by the parametric modelling algorithm Lensmodel. A comparison of all three approaches and a model-free analysis based on the relative polar angles of the multiple images corroborate the hypothesis that elliptically symmetric models are too simplistic to characterise the asymmetric mass density distribution of this lenticular or late-type galaxy. Determining the local lens properties independently of a model, the sparsity and the strong alignment of the subcomponents yield broad 1-σ confidence intervals ranging from 8% to over 1000% of the local lens property values. The lens model approaches yield comparably broad confidence intervals. Within these intervals, there is a high degree of agreement between the model-independent local lens properties of our approach based on the subcomponent positions and the local lens properties obtained by PixeLens. In addition, the model-independent approach efficiently determines local lens properties on the scale of the quasar subcomponents, which are computationally intensive to obtain by free-form model-based approaches. Relying on the quadrupole moment of each subcomponent, these small-scale local lens properties show tighter 1-σ confidence bounds by at least one order of magnitude on the average with a range of 9% to 535% of the of the local lens property values. As only 40% of the small-scale subcomponent local lens properties overlap within the confidence bounds, mass density gradients on milli-arcsecond scales cannot be excluded. Hence, aiming at a global reconstruction of the deflecting mass density distribution, increasingly detailed observations require flexible free-form models that allow for density fluctuations on milli-arcsecond scale to replace parametric ones, especially for such lenses as B0128, which have an asymmetric mass density distribution that may include localised inhomogeneities.

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26

Wu Tao, 吴涛, and 苏宙平 Su Zhouping. "Design of Free-Form Lens for Extended LED Source Based on Weighted Overlap Algorithm." Laser & Optoelectronics Progress 55, no. 12 (2018): 122202. http://dx.doi.org/10.3788/lop55.122202.

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27

Zhang, Yun, and Jing Feng Zhi. "Processing Flow of Optical Fabrication for Correcting Lenses." Advanced Materials Research 24-25 (September 2007): 117–24. http://dx.doi.org/10.4028/www.scientific.net/amr.24-25.117.

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This paper presents the processing flow and results of optical fabrication for an optical correcting lens with a free-form surface, namely a free-form lens. Because a correcting lens has no rotation axes of symmetry and its surface cannot be expressed by a continuity equation, its processing technology is different with that of general aspheric lenses. The correcting lens was firstly formed from a glass workblank with flat face using diamond abrasion wheel with spherical shape, and then loose abrasive lapped and polished with oblique axis spherical tools to decrease the surface roughness and increase the surface accuracy based on the measuring result after forming. At the lapping and polishing stages, two processing methods are employed. One is to control the processing pressure, and the other is based on dwell time. Since high precision fabrication is closely related with high precision measuring, this paper also presents a high precision non-contact optical measuring method based on image transforming for correcting lenses. The effectiveness of the processing flow and technology is confirmed by an experiment in which a workblank is processed into a satisfying correcting lens.

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28

Lee, Chang Soo, Soo Young Lee, and Dong Hoon Hyun. "Analysis of Performance on Asymmetric LED Lens Design Using Three-Dimensional Free-Form Surface Expression." Journal of the Korean Society of Manufacturing Technology Engineers 26, no. 3 (June 30, 2017): 328–36. http://dx.doi.org/10.7735/ksmte.2017.26.3.328.

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29

ZHANG Xiao-ting, 张晓婷, 陈芳萍 CHEN Fang-ping, 叶绿青 YE Lv-qing, 王孝艳 WANG Xiao-yan, 蔡智辉 CAI Zhi-hui, and 庄其仁 ZHUANG Qi-ren. "Design of Cylindrical Lens Grating Based on Free-form Surface for Naked-eye 3D Display." ACTA PHOTONICA SINICA 46, no. 12 (2017): 1222002. http://dx.doi.org/10.3788/gzxb20174612.1222002.

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30

Lin, Raychiy J., and Ching-Cherng Sun. "Free-form thin lens design with light scattering surfaces for practical LED down light illumination." Optical Engineering 55, no. 5 (May 27, 2016): 055102. http://dx.doi.org/10.1117/1.oe.55.5.055102.

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31

Liou, Chengshiun, and Chingfu Tsou. "Compact Dual-LED Packaging With a 3-D Free-Form Lens for Uniform Rectangular Illumination." IEEE Transactions on Components, Packaging and Manufacturing Technology 8, no. 4 (April 2018): 578–87. http://dx.doi.org/10.1109/tcpmt.2017.2781279.

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32

Quoc Anh, Nguyen Doan, Min-Feng Lai, Hsin-Yi Ma, and Hsiao-Yi Lee. "Design of a free-form lens for LED light with high efficiency and uniform illumination." Applied Optics 53, no. 29 (August 27, 2014): H140. http://dx.doi.org/10.1364/ao.53.00h140.

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33

Liu, Dianhong, Xiaohui Zhang, and Chen Chen. "Free-form lens for rectangular illumination with the target plane rotating at a certain angle." Journal of the Optical Society of America A 32, no. 11 (October 7, 2015): 1958. http://dx.doi.org/10.1364/josaa.32.001958.

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34

Lam, Daniel, Tom Broadhurst, Jose M. Diego, Jeremy Lim, Dan Coe, Holland C. Ford, and Wei Zheng. "A RIGOROUS FREE-FORM LENS MODEL OF A2744 TO MEET THE HUBBLE FRONTIER FIELDS CHALLENGE." Astrophysical Journal 797, no. 2 (December 4, 2014): 98. http://dx.doi.org/10.1088/0004-637x/797/2/98.

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35

Liu, Dianhong, Xiaohui Zhang, Chen Chen, Shang Zhang, and Hongwei Han. "Fast double free-form LED lens design for tiny rectangular light field with high efficiency." Optical Review 26, no. 4 (June 21, 2019): 349–55. http://dx.doi.org/10.1007/s10043-019-00515-5.

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36

Long, You, Ming Wu Kang, and Xiao Xia Li. "Design of Free-Form Surface Optic in Wide Field of View Off-Axis Optical System." Applied Mechanics and Materials 50-51 (February 2011): 806–11. http://dx.doi.org/10.4028/www.scientific.net/amm.50-51.806.

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Design of off-axis system is a hot and difficult topic in optical design area. The wide field of view(WFOV) off-axis system this paper involved always have the drawbacks of complicated large size and great weight. This paper introduces an application of free-form surface(FFS) in WFOV off-axis optical system design, analyzes FFS optics’ material and fabrication methods. The system uses one FFS lens and one doublet, image quality meets the design specification, and characterizes by simple structure and lightweight.

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37

Liang, Fu Sheng, Ji Zhao, Shi Jun Ji, and Xin Wang. "Spherical Approximation of Free-Form Surface Closed to a Sphere in Semi-Finishing." Key Engineering Materials 679 (February 2016): 199–206. http://dx.doi.org/10.4028/www.scientific.net/kem.679.199.

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The free-form surface closed to a sphere of brittle material has been used widely, but it is difficult for machining and the efficiency of processing is insufficient. In order to get a product, several processes are needed, such as rough machining, semi-finishing and finishing. Axisymmetric curved surface can take place of the free-form surface in roughing or semi-finishing for wiping off the mass allowance efficiently. Therefore, a spherical approximation algorithm of free-form surface closed to sphere is presented in which free-form surface optical lens will be replaced by a spherical surface in semi-finishing and get the approximate sphere of the free-form surface. It can be certified in the test that this method is simple and reliable. The efficiency and precision in machining is excellent and the distribution of allowance for finishing is uniform in the whole surface, which has great practical significance in machining of optical free-form surface of brittle materials.

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38

Duerr, Fabian, Pablo Benítez, Juan C. Miñano, Youri Meuret, and Hugo Thienpont. "Analytic design method for optimal imaging: coupling three ray sets using two free-form lens profiles." Optics Express 20, no. 5 (February 22, 2012): 5576. http://dx.doi.org/10.1364/oe.20.005576.

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39

Lam, Daniel. "A New Approach to Free-form Cluster Lens Modeling Inspired by the JPEG Image Compression Method." Publications of the Astronomical Society of the Pacific 131, no. 1005 (October 4, 2019): 114505. http://dx.doi.org/10.1088/1538-3873/ab35c0.

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40

LICATA, JOAN E. "INVARIANTS FOR LEGENDRIAN KNOTS IN LENS SPACES." Communications in Contemporary Mathematics 13, no. 01 (February 2011): 91–121. http://dx.doi.org/10.1142/s0219199711004178.

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In this paper, we define invariants for primitive Legendrian knots in lens spaces L(p, q), q ≠ 1. The main invariant is a differential graded algebra [Formula: see text] which is computed from a labeled Lagrangian projection of the pair (L(p, q), K). This invariant is formally similar to a DGA defined by Sabloff which is an invariant for Legendrian knots in smooth S1-bundles over Riemann surfaces. The second invariant defined for K ⊂ L(p, q) takes the form of a DGA enhanced with a free cyclic group action and can be computed from a cyclic cover of the pair (L(p, q), K).

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41

Joseph, R., F. Courbin, J. L. Starck, and S. Birrer. "Sparse Lens Inversion Technique (SLIT): lens and source separability from linear inversion of the source reconstruction problem." Astronomy & Astrophysics 623 (February 25, 2019): A14. http://dx.doi.org/10.1051/0004-6361/201731042.

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Strong gravitational lensing offers a wealth of astrophysical information on the background source it affects, provided the lensed source can be reconstructed as if it was seen in the absence of lensing. In the present work, we illustrate how sparse optimisation can address the problem. As a first step towards a full free-form-lens-modelling technique, we consider linear inversion of the lensed source under sparse regularisation and joint deblending from the lens light profile. The method is based on morphological component analysis, assuming a known mass model. We show with numerical experiments that representing the lens and source light using an undecimated wavelet basis allows us to reconstruct the source and to separate it from the foreground lens at the same time. Both the source and lens light have a non-analytic form, allowing for the flexibility needed in the inversion to represent arbitrarily small and complex luminous structures in the lens and source. In addition, sparse regularisation avoids over-fitting the data and does not require the use of an adaptive mesh or pixel grid. As a consequence, our reconstructed sources can be represented on a grid of very small pixels. Sparse regularisation in the wavelet domain also allows for automated computation of the regularisation parameter, thus minimising the impact of the arbitrary choice of initial parameters. Our inversion technique for a fixed mass distribution can be incorporated into future lens-modelling techniques iterating over the lens mass parameters.

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42

Hamidzadeh, H. R., and L. Moxey. "Analytical modal analysis of thin-film flat lenses." Proceedings of the Institution of Mechanical Engineers, Part K: Journal of Multi-body Dynamics 219, no. 1 (March 1, 2005): 55–59. http://dx.doi.org/10.1243/146441905x9999.

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The free vibrations of circular and elliptical thin-film lens are investigated. In particular, linear closed-form solutions for free vibrations of these structures were achieved and modal analysis was performed. The vibration response of the thin-film membranes were mathematically modelled using the Mathieu equation. Numerical results for various nodal diameters were computed. For the limited case, when an elliptical lens becomes circular, an excellent comparison was established with the available analytical solution. Experimental analyses were conducted to determine the effects of various parameters, such as material properties, membrane pre-strain rate, and the geometry, on natural frequency and mode shapes of these structures. The comparison verified the adequacy of linear solutions to predict the dynamic response of thin-film lenses.

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43

Al-ababneh, Nedal. "Crosstalk Modeling in Lens Based Free Space Optical Interconnects Systems with Circular Symmetry." Modern Applied Science 12, no. 6 (May 28, 2018): 112. http://dx.doi.org/10.5539/mas.v12n6p112.

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We introduce convenient model and an optimization scheme to optimize the signal-to-crosstalk ratio (SCR) in a free space optical interconnects (FSOIs) system that uses microlenses with finite circular apertures. In this model, we consider both the stray light crosstalk and the crosstalk due to the diffraction at the microlens apertures to evaluate the SCR. Using cylindrical form of Collins diffraction integral and the Laguerre–Gaussian (LG) beam model, we derive an approximate closed form formula for the optical field of a multimode LG beam propagating through circular apertured FSOIs by expanding the hard edge circular aperture function of the microlens in terms of complex Gaussian functions. The analyses indicate that the size of the detector is an important factor to optimize the SCR for both the apertured and the unapertured misaligned FSOIs system. The effect of higher order mode of the laser source on the SCR is also considered.

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44

Shi, Zhi Wei, Guo Dong Yan, Guo Qiang Deng, De Han Luo, Qin Ruo Wang, Ming Juan Liang, and Bing Zhong Zhu. "New Feedback Optimization Method Based on Arithmetic Sequence for an Extended LED Source." Applied Mechanics and Materials 385-386 (August 2013): 1898–901. http://dx.doi.org/10.4028/www.scientific.net/amm.385-386.1898.

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A new feedback optimization design method based on arithmetic sequence is proposed to design free-form optical systems for an extended LED source. Taken LED lens designed by this method as an example, we find that the design process is simple and high regional illuminance uniformity and high light output efficiency could be simultaneously achieved.

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45

Wride, Michael A. "Lens fibre cell differentiation and organelle loss: many paths lead to clarity." Philosophical Transactions of the Royal Society B: Biological Sciences 366, no. 1568 (April 27, 2011): 1219–33. http://dx.doi.org/10.1098/rstb.2010.0324.

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The programmed removal of organelles from differentiating lens fibre cells contributes towards lens transparency through formation of an organelle-free zone (OFZ). Disruptions in OFZ formation are accompanied by the persistence of organelles in lens fibre cells and can contribute towards cataract. A great deal of work has gone into elucidating the nature of the mechanisms and signalling pathways involved. It is apparent that multiple, parallel and redundant pathways are involved in this process and that these pathways form interacting networks. Furthermore, it is possible that the pathways can functionally compensate for each other, for example in mouse knockout studies. This makes sense given the importance of lens clarity in an evolutionary context. Apoptosis signalling and proteolytic pathways have been implicated in both lens fibre cell differentiation and organelle loss, including the Bcl-2 and inhibitor of apoptosis families, tumour necrosis factors, p53 and its regulators (such as Mdm2) and proteolytic enzymes, including caspases, cathepsins, calpains and the ubiquitin–proteasome pathway. Ongoing approaches being used to dissect the molecular pathways involved, such as transgenics, lens-specific gene deletion and zebrafish mutants, are discussed here. Finally, some of the remaining unresolved issues and potential areas for future studies are highlighted.

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Skryabina, Yelena V., Yuriy S. Astakhov, Yanina S. Konenkova, Tatiana S. Varganova, Vladimir P. Petukhov, Kseniya V. Nokhrina, and Kaleriya O. Dnestryanskaya. "Acanthamoeba keratitis. Review of literature. Case reports." Ophthalmology journal 12, no. 1 (June 6, 2019): 59–71. http://dx.doi.org/10.17816/ov2019159-71.

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Acanthamoeba keratitis (АК) is a parasitic infectious condition caused by corneal invasion by free-living amoebae. In 86% of cases, AK affects contact lens wearers. Delayed diagnosis and inadequate treatment of this disease leads to development of a severe form of keratouveitis and corneal perforation. Consequently, this group of diseases is one of the causes of visual disability in working-age population.

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Diego, Jose M., S. M. Molnar, C. Cerny, T. Broadhurst, R. Windhorst, A. Zitrin, R. Bouwens, D. Coe, C. Conselice, and K. Sharon. "Free-form Lens Model and Mass Estimation of the High-redshift Galaxy Cluster ACT-CL J0102-4915, “El Gordo”." Astrophysical Journal 904, no. 2 (November 25, 2020): 106. http://dx.doi.org/10.3847/1538-4357/abbf56.

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48

Benedict, Cathy. "Processes of alienation: Marx, Orff and Kodaly." British Journal of Music Education 26, no. 2 (June 3, 2009): 213–24. http://dx.doi.org/10.1017/s0265051709008444.

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Using Marx as a lens through which to interrogate music methodology, in particular those espoused by Orff and Kodaly, this article suggests that rather than the free play and creativity Orff and Kodaly intended, the implementation of these methods in a strict and unmindful manner, often alienates both teacher and student from musicking. Thus these methods have become more real than the music itself and as such, music making within them is abstracted from the use-value of musicking and consequently exchanged as a commodity. The article explains how methods become a form of production that serves to reproduce systems of domination as well as a very particular form of cultural capital. This lens also allows us to realise that, as we move farther away from the process of inquiry originally embedded in the conception and construction of these musical engagements, the educative process becomes more and more myopic. This, in turn, determines, delineates and narrows possibilities of and for meaningful learning.

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49

Ghosh, Agniva, Liliya L. R. Williams, Jori Liesenborgs, Ana Acebron, Mathilde Jauzac, Anton M. Koekemoer, Guillaume Mahler, et al. "Further support for a trio of mass-to-light deviations in Abell 370: free-form grale lens inversion using BUFFALO strong lensing data." Monthly Notices of the Royal Astronomical Society 506, no. 4 (April 28, 2021): 6144–58. http://dx.doi.org/10.1093/mnras/stab1196.

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ABSTRACT We use the Beyond Ultra-deep Frontier Fields and Legacy Observations (BUFFALO) strong lensing image catalogue of the merging galaxy cluster Abell 370 to obtain a mass model using free-form lens inversion algorithm grale. The improvement of the strong lensing data quality results in a lens plane rms of only 0.45 arcsec, about a factor of two lower than that of our existing HFF v4 reconstruction. We attribute the improvement to spectroscopic data and use of the full reprocessed HST mosaics. In our reconstructed mass model, we found indications of three distinct mass features in Abell 370: (i) a ∼35 kpc offset between the northern BCG and the nearest mass peak, (ii) a ∼100 kpc mass concentration of roughly critical density ∼250 kpc east of the main cluster, and (iii) a probable filament-like structure passing N-S through the cluster. While (i) is present in some form in most publicly available reconstructions spanning the range of modelling techniques: parametric, hybrid, and free-form, (ii) and (iii) are recovered by only about half of the reconstructions. We tested our hypothesis on the presence of the filament-like structure by creating a synthetic cluster – Irtysh IIIc – mocking the situation of a cluster with external mass. We also computed the source plane magnification distributions. Using them, we estimated the probabilities of magnifications in the source plane, and scrutinized their redshift dependence. Finally, we explored the lensing effects of Abell 370 on the luminosity functions of sources at zs = 9.0, finding it consistent with published results.

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Lei, Xiang Yang, Hao Huang, Feng Yang, Xian Hua Chen, and Qiao Xu. "On-Machine Profile Measuring System for Grinding Surface of Aspheric Lens." Advanced Materials Research 156-157 (October 2010): 1613–21. http://dx.doi.org/10.4028/www.scientific.net/amr.156-157.1613.

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In this paper, an on-machine profile measuring system for aspheric ground surface was presented, which involved data processing with improved two-dimensional weighted mean filtering and free form surface fitting. To verify the reliability of this system, a calibration experiment was done by comparing the measuring results of Ф320mm mirror between the WYKO 24 inch interferometer and the on-machine measuring system. The experiment results show that the on-machine measurement is effective and it can provide foundation for compensation machining. By comparing the measurement experiment results of the Keyence LC2430 with the WYKO interferometer, it is demonstrated that the deviation of PV is better than 0.23μm and the deviation of RMS better than 0.08μm.

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