Key Laboratory of Optical Information Science and Technology

Tianjin, China

Key Laboratory of Optical Information Science and Technology

Tianjin, China
SEARCH FILTERS
Time filter
Source Type

Zhai Y.,Nankai University | Zhai Y.,Key Laboratory of Optical Information Science and Technology | Liu Y.-J.,Nankai University | Liu Y.-J.,Key Laboratory of Optical Information Science and Technology | And 2 more authors.
Chinese Optics | Year: 2015

In order to assist venipuncture and related medical operations, a novel vein imaging device based on head-mounted projective display(HMPD) is designed. The correspondent optical system consists of near-infrared imaging system and see-through HMPD. With the help of optical design software ZEMAX, the near-infrared imaging system has a large numerical aperture with F number of 2.6, which is extremely conducive to receive and to image the weak reflected near-infrared light. The structure of the optical system of HMPD is same as that of near-infrared imaging part, which is conducive to simplify the processing and assembly. The results indicate that the performance of imaging system is excellent and the resolution is up to QXGA(2 048×1 536). The see-through HMPD possesses an 18 mm exit pupil and a 25 mm eye relief, with the field curvature less than 0.03 D, the distortion less than 0.32% and the resolution up to QXGA. Compared with the current vein imaging device, the proposed system is characterized by compact structure, comfort wearing and ultrahigh resolution, which is suitable for assistant tools in venipuncture techniques. ©, 2015, Editorial Office of Chinese Optics. All right reserved.


Zheng S.,Nankai University | Zheng S.,Key Laboratory of Optical Information Science and Technology | Wang Z.,Nankai University | Wang Z.,Key Laboratory of Optical Information Science and Technology | And 4 more authors.
Applied Optics | Year: 2012

The aim of this paper is to propose a method for designing aspheric spectacles capable of realizing good optical performance at both far and near vision for presbyopia. We have experimentally measured wavefront aberrations and axial lengths for eight myopic eyes. In consideration of the field of view (FOV), the rotation of the eyeball, and a small amount of accommodation retained for presbyopia, we constructed individual eye models and optimized all the spectacle-eye systems for visible wavelengths by Zemax's simulation. Finally, we evaluated the image quality by the modulation transfer function (MTF) and visual acuity (VA) with different pupil sizes (2, 2.8, 4 mm). Results show that when the pupil size is 2mmor 2.8 mm, the spectacles designed for the full FOV (0° and±4° FOV) provide a strong ability to transfer low contrast at both far and near vision, and the VA for all reaches 0.8, and up to 1.1 for eyes NO. 1, NO. 5, NO. 6, and NO. 8 for the 0° FOV. As the pupil size increases to 4 mm, the VA for all comes to 0.6 for the full FOV, indicating that presbyopia is able to acquire a good visual resolution at both far and near vision by the designed aspheric spectacles. Furthermore, we verified the visual continuity of the spectacle-eye systems by studying intermediate vision, which demonstrates that the method used in our design is accurate and practicable. © 2012 Optical Society of America.


Chen S.,Nankai University | Fan F.,Nankai University | Wang X.,Nankai University | Wu P.,Key Laboratory of Optical Information Science and Technology | And 2 more authors.
Optics Express | Year: 2015

A magneto-metasurface with nonreciprocal terahertz (THz) transmission has been proposed to form a THz isolator. Importantly, we have discussed the two necessary conditions for THz nonreciprocal transmission in the metasurface: (1) There should be magneto-optical responses for THz waves in the metasurface; (2) The transmission system of the metasurface needs to be asymmetric for forward and backward waves. These two conditions lead to the time reversal symmetry breaking of system, and the magnetoplasmon mode splitting and nonreciprocal resonance enhancement can be observed in the asymmetry magnetometasurface. Moreover, the isolation dependences and tunability on the external magnetic field and temperature have also been investigated, which shows that the best operating state with a high isolation can be designed. The numerical simulations show a maximum isolation of 43 dB and a 10 dB operating bandwidth of 20 GHz under an external magnetic field of 0.3 T, and the insertion loss is smaller than 1.79 dB. This low-loss, high isolation, easy coupling THz isolator has broadly potentials for THz application systems. © 2015 Optical Society of America.


Liang Z.,Nankai University | Wu P.,Key Laboratory of Optical Information Science and Technology | Wu P.,Nankai University
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2015

An all-optical switching device is demonstrated with a nonlinear waveguide structure filled with liquid crystal. The signal field coupled out the glass cladding has interesting intensity-depended property due to the coupling of two different nonlinear dynamics in the nonlinear optical layer. The device has an additional feature that the switching sign is controllable from positive to negative. © 2015 SPIE.


Chen S.,Nankai University | Fan F.,Nankai University | Wu P.,Nankai University | Liu B.,Key Laboratory of Optical Information Science and Technology | Chang S.,Key Laboratory of Optical Information Science and Technology
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2015

In this paper, we have reviewed our research on terahertz (THz) isolators and nonreciprocal transmission devices. In addition, we present a new kind of THz isolator based on asymmetry magneto-metasurface. A structured InSb layer coats on the silica substrate in which the numerical simulation shows that this metasurface has isolation over 60dB at 0.646 THz and a 10dB operating bandwidth of 13 GHz under an external magnetic field of 0.3T with an insertion loss less than 2.5dB. This kind of low-loss, high isolation, easy coupling THz magneto-metasurface isolator has broadly potentials for THz application systems. Importantly, we discuss and conclude the necessary conditions of forming THz nonreciprocal transmission in the magneto-material devices, which is strongly related with magneto-material and asymmetric transmission system. © 2015 SPIE.


Wu P.,Key Laboratory of Optical Information Science and Technology | Wu P.,Nankai University | Tang S.,Crystal Research, Inc.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2015

Currently available wavelength-tunable lasers have technical difficulty in combining high-speed, continuous and wide wavelength tunability with high output power. We demonstrated a high-speed wavelength-tunable laser based on a fast electro-optic effect. We observed that the wavelength-swept speed exceeds 107 nm/s at center wavelength of 1550 nm with continuous wavelength tunability. Moreover, the maximum output power is over 100 mW and the wavelength tuning range is near 100 nm with a full width at half maximum of less than 0.5 nm. © 2015 SPIE CCC.


Lou Q.,Nankai University | Lou Q.,Key Laboratory of Optical Information Science and Technology | Wang Y.,Tianjin Medical University | Wang Z.,Nankai University | And 8 more authors.
Applied Optics | Year: 2015

We propose a method of constructing an individual eye model with a large visual field, and then investigate aberration characteristics of eyes in peripheral fields with constructed models. Twelve eyes of different aberrations are selected from 89 myopic eyes. It is shown that astigmatism increases as visual field in a quadratic manner. The variation tendency of defocus can be expressed by the cubic curve for 50% of eyes. For most of the eyes, the variation of spherical aberration shows a quadratic rule within 24° visual field. Coma exhibits obvious individual differences. The impact of high-order aberrations on vision is mainly at a smaller visual field, and it becomes negligible beyond 24° visual field. © 2015 Optical Society of America.


He Y.,Nankai University | He Y.,Key Laboratory of Optical Information Science and Technology | Wang Y.,Tianjin Medical University | Wang Z.,Nankai University | And 10 more authors.
Biomedical Optics Express | Year: 2013

Two kinds of individual eye models, involving and without involving the angle between visual axis and optical axis, are established by means of optical design. We use them to study the properties of the transverse chromatic aberration (TCA) and longitudinal chromatic aberration (LCA) over the visible spectrum. Then the effects of the LCA and TCA on the visual quality of human eyes are evaluated. The statistical averages of TCA and LCA over the visible spectrum for Chinese myopic eyes are obtained. Results show that both TCA and LCA restrict the visual performance, and LCA is more detrimental than TCA. © 2013 Optical Society of America.


Li R.,Nankai University | Li R.,Key Laboratory of Optical Information Science and Technology | Wang Z.Q.,Nankai University | Wang Z.Q.,Key Laboratory of Optical Information Science and Technology | And 4 more authors.
Science China Technological Sciences | Year: 2012

Aiming at the correction of high-order aberrations of human eye with spectacles, a design method of aspheric spectacles is proposed based on the eye's wavefront aberrations data. Regarding the eyeball and the spectacles as a whole system - the lens-eye system - the surface profiles of the spectacles are achieved by optimization procedure of lens design. Different from the conventional optometry, in which the refraction prescription is acquired with a visual chart, the design takes into account the two aspects of actual human viewing, eyeball rolling and certain distinct viewing field. The rotation angle of eyeball is set to be ±20° as wearing spectacles, and the field of view is set to be ±7° which is especially important as watching screen display. The individual eye model is constructed as the main part of the lens-eye system. The Liou eye model is modified by sticking a thin meniscus lens to the crystalline lens. Then the defocus of the individual eye is transferred to the front surface of the meniscus lens, and the astigmatism and high-order aberrations are transferred to the front surface of the cornea. 50 eyes are involved in this research, among which 36 eyes have good enough visual performance already after sphero-cylindrical correction. 10 eyes have distinct improvement in vision and 4 eyes have no visual improvement by further aspheric correction. 6 typical subject eyes are selected for the aberrations analysis and the spectacles design in this paper. It is shown that the validity of visual correction of aspheric lens depends on the characteristics of the eye's wavefront aberrations, and it is effective for the eye with larger astigmatism or spherical aberration. Compared with sphero-cylindrical correction only, the superiority taken by the aspheric correction is mainly on the improvement of MTF at a larger field of view. For the best aspheric correction, the MTF values increase by 18.87%, 38.34%, 44.36%, 51.29% and 57.32% at the spatial frequencies of 40, 80, 100, 125 and 150 cycles/ mm, respectively. © Science China Press and Springer-Verlag Berlin Heidelberg 2012.


Chen M.,Nankai University | Fan F.,Nankai University | Wu P.,Key Laboratory of Optical Information Science and Technology | Zhang H.,China University of Petroleum - East China | Chang S.,Key Laboratory of Optical Information Science and Technology
Optics Communications | Year: 2015

We have proposed an electrically controllable terahertz (THz) beam scanning device based on asymmetric graphene plasmonic grating. It is proved that the dispersion relation of surface plasmon waves can be efficiently manipulated on the periodic metal-dielectric-graphene plasmonic structure by an external bias voltage, and thus the derivation angle of the THz beam can be actively tuned. The numerical results show that the radiation angle of THz waves through this device can be tuned from -18° to 18° with the bias changing from 53.5 mV into 368.8 mV at the operating frequency of 0.5 THz. This electrically active beam scanning device has important application in the THz imaging, radar and communication systems. © 2015 Elsevier B.V. All rights reserved.

Loading Key Laboratory of Optical Information Science and Technology collaborators
Loading Key Laboratory of Optical Information Science and Technology collaborators