Results 51 to 60 of about 470 (166)

The simultaneous enhancement of photorefraction and optical damage resistance in MgO and Bi2O3 co-doped LiNbO3 crystals

, 2016
For a long time that optical damage was renamed as photorefraction, here we find that the optical damage resistance and photorefraction can be simultaneously enhanced in MgO and Bi2O3 co-doped LiNbO3 (LN:Bi,Mg). The photorefractive response time of LN:Bi,
Liu, Shiguo (School of Physics, Nankai University), Xu, Jingjun (School of Physics, Nankai University), Zheng, Dahuai (School of Physics, Nankai University), Chen, Shaolin (MOE Key Laboratory of Weak-Light Nonlinear Photonics and TEDA Applied Physics School, Nankai University), Zhang, Ling (MOE Key Laboratory of Weak-Light Nonlinear Photonics and TEDA Applied Physics School, Nankai University), Kong, Yongfa (MOE Key Laboratory of Weak-Light Nonlinear Photonics and TEDA Applied Physics School, Nankai University), Chen, Muling (School of Physics, Nankai University), Rupp, Romano (Faculty of Physics, Faculty of Physics, University of Vienna)   +7 more
core   +1 more source

Electrically pumped soliton microcombs on thin‐film lithium niobate

Nanophotonics, Volume 14, Issue 26, Page 4813-4819, December 2025.
Abstract Thin‐film lithium niobate (TFLN) has enabled efficient on‐chip electro‐optic modulation and frequency conversion for information processing and precision measurement. Extending these capabilities with optical frequency combs unlocks massively parallel operations and coherent optical‐to‐microwave transduction, which are achievable in TFLN ...
Xiaomin Lv, Ze Wang, Tianyu Xu, Chen Yang, Xing Jin, Binbin Nie, Du Qian, Yanwu Liu, Kaixuan Zhu, Bo Ni, Qihuang Gong, Fang Bo, Qi‐Fan Yang   +12 more
wiley   +1 more source

Smartphones in ophthalmology

Indian Journal of Ophthalmology, 2012
The potential usefulness of smartphones in the medical field is evolving everyday. This article describes various tools available on smartphones, largely focusing on the iPhone, for the examination of an ophthalmic patient, for patient and physician ...
Jay Chhablani, Simon Kaja, Vinay A Shah
doaj   +1 more source

Defective structure and photorefractive properties of double doped crystals LiNbO3 : Fe : Mg and LiNbO3 : Fe : Zn [PDF]

Физико-химические аспекты изучения кластеров, наноструктур и наноматериалов, 2018
A comparative analysis of photorefractive properties was carried out for congruent, stoichiometric and double doped lithium niobate crystals: LiNbO3 : Fe(0,009) : Mg(5,04) and LiNbO3 : Fe(0,02) : Zn(4,34) mol %.
N.A. Teplyakova, N.V. Sidorov, M.N. Palatnikov   +2 more
doaj   +1 more source

Radiation Modification of Optical Characteristics of LiNbO₃:Zn and LiNbO₃:Mg Crystals

Crystals, 2022
The modification of the optical characteristics of LiNbO3:Zn and LiNbO3:Mg crystals grown by the Czochralski method was investigated using β and γ radiation.
Mikhail Palatnikov, Nikolay Sidorov, Sergey Panasjuk, Natalya Teplyakova, Olga Makarova   +4 more
doaj   +1 more source

Accuracy and precision of a sphero‐cylindrical over‐refraction app for smartphones

Ophthalmic and Physiological Optics, Volume 45, Issue 7, Page 1662-1675, November 2025.
Abstract Purpose To evaluate the accuracy and precision of a web‐based smartphone app designed to measure sphero‐cylindrical over‐refraction. Methods A total of 307 healthy young subjects (22.5 ± 3.4 years) underwent clinical subjective refraction. In addition to each subject's refractive correction, spherical and cylindrical errors from −1.50 to 0.00 ...
Rosa Maria Salmeron‐Campillo, Gines Martinez‐Ros, Jose Angel Diaz‐Guirado, Carmen Travel‐Alarcon, Mateusz Jaskulski, Norberto Lopez‐Gil   +5 more
wiley   +1 more source

Deep Learning–Based Prediction of Refractive Error Using Photorefraction Images Captured by a Smartphone: Model Development and Validation Study

JMIR Medical Informatics, 2020
BackgroundAccurately predicting refractive error in children is crucial for detecting amblyopia, which can lead to permanent visual impairment, but is potentially curable if detected early.
Chun, Jaehyeong, Kim, Youngjun, Shin, Kyoung Yoon, Han, Sun Hyup, Oh, Sei Yeul, Chung, Tae-Young, Park, Kyung-Ah, Lim, Dong Hui   +7 more
doaj   +1 more source

Deep learning–empowered low‐cost portable automated refraction system: A solution to the inadequate effective correction rate of refractive errors in resource‐limited areas

Ophthalmic and Physiological Optics, Volume 45, Issue 7, Page 1676-1688, November 2025.
Abstract Aims To develop and validate a low‐cost, portable automated refraction system (Tongren Digital Sight, TRDS) using deep learning and infrared eccentric photorefraction to improve refractive error correction in resource‐constrained settings. Methods This randomised controlled crossover trial enrolled 282 participants (18–60 years of age) at ...
Huang Yan, Zhen Yi, Sun Qilin, Chang Hong, Huang Yan, Tang Wei   +5 more
wiley   +1 more source

Calibration of the PlusOptix PowerRef 3 with change in viewing distance, adult age and refractive error

Ophthalmic and Physiological Optics, Volume 39, Issue 4, Page 253-259, July 2019., 2019
Abstract Purpose The PowerRef 3 is frequently used in studying the near triad of accommodation, vergence and pupil responses in normal and clinical populations. Within a range, the defocus measurement of the PowerRef 3 is linearly related to the eye's defocus. While the default factory‐calibrated slope of this relation (calibration factor) is 1, it has
Saeideh Ghahghaei, Olivia Reed, T Rowan Candy, Arvind Chandna   +3 more
wiley   +1 more source

Delayed-onset bilateral abducens paresis after head trauma

Indian Journal of Ophthalmology, 2012
Bilateral sixth nerve paresis following closed head injury, though rare, is a known entity. However, delayed-onset post-traumatic bilateral abducens paresis is extremely rare. We present two cases.
Pravin Salunke, Amey Savardekar, Sukumar Sura   +2 more
doaj   +1 more source