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- 摘要
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- 实验方案
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Aberrated Microlenses to Reduce Crosstalk in Free Space Optical Interconnects Systems
摘要： A free space optical interconnects system that uses Gaussian beams and focusing microlenses with spherical aberration has been considered. Numerical results show that the use of microlenses with negative spherical improves the signal-to-crosstalk ratio of the interconnects system at some optimum positions of the detector array. An expression for output field at the detectors plane is derived and used to evaluate the signal-to-crosstalk ratio.
关键词： lens spherical aberration,optical crosstalk,free space optical interconnects
更新于2025-09-23 15:23:52
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Optimized rotation of an optically trapped particle for micro mixing
摘要： The angular momentum transferred by circularly polarized photons is able to rotate an optically trapped microparticle. Here, the optically rotating particle is introduced as an active micromixer to reduce the mixing time in a microfluidic system. To optimize the system for microfluidic application, the effect of several optical parameters such as spherical aberration and the numerical aperture of the objective on the rotation rate of a trapped particle is investigated. The results show that the optimized depth for the rotation of a particle is located close to the coverslip and can be changed by a fine adjustment of the refractive index of the immersion oil. By applying the obtained optimized optical parameters on a trapped particle at the interface of two fluids in a microchannel, the mixing length is reduced by a factor of (cid:2)2.
关键词： microfluidics,numerical aperture,micromixing,angular momentum,optical trapping,spherical aberration
更新于2025-09-23 15:21:21
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Optimizing optical tweezing with directional scattering in composite microspheres
摘要： We demonstrate that achieving zero backward scattering (ZBS), i.e., the first Kerker condition, allows for optical tweezing of high-index microspheres, which cannot be trapped using standard techniques. For this purpose, we propose an alternative material platform based on composite metamaterials. By tuning the volume filling fraction of inclusions and the microsphere radius, stable trapping can be achieved provided that ZBS is combined with the condition for destructive interference between the fields reflected at the external and internal interfaces of the microsphere when located at the focal point. By using the Mie-Debye-spherical aberration theory, we also show that the ZBS condition is even more useful in realistic, standard optical tweezer setups, in which spherical aberration is unavoidable due to refraction at the interface between the glass slide and the water-filled sample. Altogether, our findings not only pave the way for possible new trapping designs and applications but also unveil the role of backscattering in the physics of optical tweezers.
关键词： Kerker condition,optical tweezing,Mie-Debye-spherical aberration theory,directional scattering,composite microspheres
更新于2025-09-23 15:21:01
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Laser multi-focus precision cutting of thick sapphire by spherical aberration rectification
摘要： Laser multi-focus separation technology is an effective way to cut thick, transparent and hard materials. In this paper, factors affecting the quality of multi-focus cutting sapphire were investigated. Optical simulations analysis was performed based on experimental results to analyze multi-focal laser beam propagation from air into sapphire. The results show that the focus interval is linearly dependent on refractive index. Spherical aberration due to refractive-index mismatch disperses the laser foci, leading to a reduction in laser power density which has a significant influence on the cutting quality. The aberration is strongly dependent on the refractivity of the material and the effective numerical aperture (NA). By redesigning the distribution of multiple foci to correct spherical aberration, sapphire with a thickness of 2 mm was cut successfully at a scanning speed of 4 mm/s. The roughness of the cutting section was ～2.5 μm , without obvious observed micro-cracks.
关键词： Optical simulation,Spherical aberration,Multi-focus,Sapphire
更新于2025-09-19 17:13:59
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Exploration of the resolving power for a magnetic lens using Glaser field distribution
摘要： Resolution estimation for magnetic lenses have been investigated using Glaser Bell-Shaped model. The adopted model used to approximates the magnetic field distribution for the proposed lens. Indeed, the field distribution is formulated in terms of three optimization parameters namely the half width, field beak value and lens length. Four values for each of these parameters selected to check the resolution behavior, where the other two parameter maintained fixed. Results reveals that the resolution get better enhancement whenever the field excitation increases. This behavior attained whenever the variation in the optimization variable leads to increases the field refracting power. Besides, the slope of the approximated model correspondingly always becomes better for long and strong magnetic lenses.
关键词： spherical aberration,Resolution,Glaser model,correction,magnetic lens
更新于2025-09-19 17:13:59
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[Laser Institute of America ICALEO?? 2017: 36th International Congress on Applications of Lasers & Electro-Optics - Atlanta, Georgia, USA (October 22a??26, 2017)] International Congress on Applications of Lasers & Electro-Optics - Aberration control by high NA focusing in transparent media
摘要： High numerical aperture (NA) focusing of light in transparent media is important in microscopy, various techniques of optical data storage and laser microprocessing. By high NA focusing through a flat bounding surface of a medium there appears positive spherical aberration reducing energy concentration and lowering physical resolution. The deeper is focusing and higher NA, the stronger is aberration and light scattering. By laser material processing there appears uncontrolled energy distribution along optical axis that makes inherently complex physical processes of laser radiation interaction with material even more complex and less predictable. To control the spherical aberration induced by internal high NA focusing it is suggested to apply specially designed aplanatic objective of patent pending optical design. The objective provides full compensation of spherical aberration for diffraction limited on-axis and off-axis high NA focusing at wide range of depths, for example from 0 to 2 mm in fused silica for NA0.8 without immersion. By setting movable components in optimum for particular depth reciprocal positions it is possible to provide not only full aberration compensation but also under- and over-compensation, thus providing control of energy distribution along optical axis at arbitrary depth and achieving special material processing effects. The paper describes design features of this optical approach as well as comparative results of spot size calculations and corresponding microphotographs of processed areas in fused silica by laser radiation focusing at various depths using NA0.8 objectives with and without compensation of aberrations.
关键词： aplanatic objective,spherical aberration,laser microprocessing,high numerical aperture,transparent media
更新于2025-09-19 17:13:59
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The Relationship between Higher-order Aberrations and Amblyopia Treatment in Hyperopic Anisometropic Amblyopia
摘要： Purpose: To investigate the relationship between higher-order aberrations (HOAs) and amblyopia treatment in children with hyperopic anisometropic amblyopia. Methods: The medical records of hyperopic amblyopia patients with both spherical anisometropia of 1.00 diopter (D) or more and astigmatic anisometropia of less than 1.00 D were reviewed retrospectively. Based on the results of the amblyopia treatment, patients were divided into two groups: treatment successes and failures. Using the degree of spherical anisometropia, subjects were categorized into mild, moderate, or severe groups. Ocular, corneal, and internal HOAs were measured using a KR-1W aberrometer at the initial visit, and at 3-month, 6-month, and 12-month follow-ups. Results: The results of the 45 (21 males and 24 females) hyperopic anisometropic amblyopia patients who completed the 12-month follow-up examinations were analyzed. The mean patient age at the initial visit was 70.3 months. In total, 28 patients (62.2%) had successful amblyopia treatments and 17 patients (37.8%) failed treatment after 12 months. Among the patient population, 24 (53.3%) had mild hyperopic anisometropia and 21 (46.7%) had moderate hyperopic anisometropia. When comparing the two groups (i.e., the success and failure groups), ocular spherical aberrations and internal spherical aberrations in the amblyopic eyes were significantly higher in the failure group at every follow-up point. There were no significant differences in any of the HOAs between mild and moderate cases of hyperopic anisometropia at any follow-up. When the amblyopic and fellow eyes were compared between the groups there were no significant differences in any of the HOAs. Conclusions: HOAs, particularly ocular spherical aberrations and internal spherical aberrations, should be considered as reasons for failed amblyopia treatment.
关键词： Hyperopia,Amblyopia,Spherical aberration,Anisometropia,Higher order aberration
更新于2025-09-09 09:28:46
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Comparison of Keratometry and Corneal Higher Order Aberrations between Scout Videokeratoscope and Pentacam Scheimpflug Camera
摘要： Purpose: To investigate the correlations of keratometry and corneal high order aberrations (HOAs) between the Keratron Scout videokeratoscope and the Pentacam HR Scheimpflug camera. Methods: From December 2012 to February 2013, keratometry and corneal HOAs were determined using the Keratron Scout videokeratoscope and Pentacam HR Scheimpflug camera in 23 healthy individuals (46 eyes). Results: Average keratometry showed high correlation with 95% confidence interval -0.155 ± 0.37 between the Keratron Scout and Pentacam HR. When comparing HOAs of the Keratron Scout and total corneal HOAs of Pentacam HR, total root-mean-square (RMS), and spherical aberration were positively correlated between the 2 devices (r = 0.67, p < 0.001 and r = 0.74, p < 0.001, respectively). When comparing HOAs of Keratron Scout and anterior corneal HOAs of Pentacam HR, total RMS, spherical aberration and coma were positively correlated between the 2 devices (r = 0.62, p < 0.001, r = 0.81, p < 0.001, and r = 0.52, p = 0.047, respectively). Conclusions: Although the 2 devices are based upon different principles, the Keratron Scout videokeratoscope and Pentacam HR Scheimpflug camera showed positive correlations in keratometry, total RMS, spherical aberration, and coma. Both devices may be useful for clinical applications.
关键词： Pentacam HR Scheimpflug camera,Spherical aberration,Keratometry,Keratron Scout videokeratoscope,Higher order aberrations
更新于2025-09-04 15:30:14
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Clinical Results and Optical Quality of Diffractive Multifocal Intraocular Lens
摘要： Purpose: To compare postoperative clinical outcomes, optical quality, and patient satisfaction between two types of diffractive multifocal intraocular lens (IOL, Acri Lisa 366D and Acrysof ReSTOR +3.00 D). Methods: In a total of 68 eyes, one of two diffractive multifocal IOL (Acri Lisa 366D and Acrysof ReSTOR +3.00 D) was implanted after cataract extraction. Visual acuity was measured postoperatively at one week, 1 month, and 6 months. Contrast sensitivity, wavefront aberration, and visual function were determined via questionnaire at postoperative 1 month. Results: Intermediate visual acuity of Acri Lisa 366D and Acrysof ReSTOR at 6 months were 0.31 ± 0.14, and 0.24 ± 0.11 (log MAR), respectively. At 6 months, near and distant visual acuity results showed no significant differences between the two groups. The photopic contrast sensitivity of Acri Lisa 366D at 6 cycles/degree was 55.36 ± 7.40 and showed significant differences with Acrysof ReSTOR (47.25 ± 9.67). The mesopic contrast sensitivity values of Acri Lisa 366D and Acrysof ReSTOR were 40.26 ± 11.38 and 28.97 ± 10.45, respectively, and the spherical aberration values were 0.037 ± 0.039 μm and 0.105 ± 0.066 μm. The spherical aberration of Acri Lisa 366D was significantly lower than that of Acrysof ReSTOR. Total and high order aberration, coma, and trefoil show no significant differences between the two groups. Conclusions: The Acri Lisa 366D multifocal IOL showed better contrast sensitivity and spherical aberration compared to Acrysof ReSTOR multifocal IOL, which had an effective intermediate visual acuity.
关键词： Contrast sensitivity,Multifocal intraocular lens,Patient satisfaction,Spherical aberration
更新于2025-09-04 15:30:14