scholarly journals Optical design of soft multifocal contact lens with uniform optical power in center-distance zone with optimized NURBS

2018 ◽  
Vol 26 (3) ◽  
pp. 3544 ◽  
Author(s):  
Lien T. Vu ◽  
Chao-Chang A. Chen ◽  
Chia-Wei Yu
Keyword(s):  
Contact Lens ◽  
Optical Design ◽  
Optical Power ◽  
Distance Zone ◽  
Center Distance

scholarly journals STUDY OF THE OPTICAL POWER OF NANOPHOTONIC SOFT CONTACT LENSES BASED ON POLY (2- HYDROXYETHYL METHACRYLATE) AND FULLERENE

2014 ◽  
Vol 5 (1) ◽  
Author(s):  
Aleksandra Debeljković Mitrović ◽  
Dragomir Stamenković ◽  
Manuel Conte ◽  
Božica Bojović ◽  
Spomenko Mihajlović
Keyword(s):  
Contact Lens ◽  
Contact Lenses ◽  
Measurement Techniques ◽  
Optical Power ◽  
Soft Contact ◽  
Standard Material ◽  
Soft Contact Lenses ◽  
Soft Contact Lens ◽  
Power Cylinder

In this paper results of comparative study of the optical power of soft contact lenses (SCL) made of standard material for SCL and nanophotonic materials with different measurement techniques used for the final contact lens controllers are presented. Three types of nanophotonic soft contact lenses were made of standard polymacon material (Soleko SP38TM) incorporated with fullerene C60, fullerol C60(OH)24 and fullerene metformin hydroxylate C60(OH)12(OC4N5H10)12. For the purposes of material characterization for potential application as soft contact lenses, the optical properties of the soft contact lenses were measured by Rotlex and Nidek device. With Rotlex device the following optical results were obtained: optical power and map of defects, while with the Nidek device: optical power, cylinder power and cylinder axis. The obtained values of optical power and map of defects showed that the optical power of synthesized nanophotonic soft contact lens is same to the nominal value, while this was not the case for the standard soft contact lens. Also, the quality of the nanophotonic soft contact lens is better than the standard one. Hence, it is possible to synthesize new nanophotonic soft contact lenses of desired optical characteristics, implying possibilities for their application in this field.

scholarly journals Characterization of nanophotonic soft contact lenses based on poly (2-hydroxyethyl methacrylate) and fullerene

2013 ◽  
Vol 67 (6) ◽  
pp. 861-870 ◽  
Author(s):  
Aleksandra Debeljkovic ◽  
Lidija Matija ◽  
Djuro Koruga
Keyword(s):  
Contact Lens ◽  
Near Infrared ◽  
Contact Lenses ◽  
Base Material ◽  
Optical Power ◽  
Sem Analysis ◽  
Hydroxyethyl Methacrylate ◽  
Soft Contact ◽  
Soft Contact Lenses ◽  
Soft Contact Lens

This work presents comparative research of characteristics of a basic and new nanophotonic material, the latter of which was obtained by incorporation fullerene, C60, in the base material for soft contact lenses. The basic (SL38) and nanophotonic materials (SL38-A) for soft contact lenses were obtained by radical polymerization of 2-hydroxyethyl methacrylate and 2-hydroxyethyl methacrylate and fullerene, which were derived by the technology in the production lab of the company Soleko (Milan, Italy). The materials were used for production of soft contact lenses in the company Optix (Belgrade, Serbia) for the purposes of this research. Fullerene was used due to its apsorption transmission characteristics in ultraviolet, visible and near infrared spectrum. For the purposes of material characterization for potential application as soft contact lenses, network parameters were calculated and SEM analysis of the materials was performed while the optical properties of the soft contact lenses were measured by a Rotlex device. The values of the diffusion exponent, n, close to 0.5 indicated Fick's kinetics corresponding to diffusion. The investigated hydrogels could be classified as nonporous hydrogels. With Rotlex device, values of optical power and map of defects were showed. The obtained values of optical power and map of defects showed that the optical power of synthesized nanophotonic soft contact lens is identical to the nominal value while this was not the case for the basic lens. Also, the quality of the nanophotonic soft contact lens is better than the basic soft contact lens. Hence, it is possible to synthesize new nanophotonic soft contact lenses of desired optical characteristics, implying possibilities for their application in this field.

Analysis on multifocal contact lens design based on optical power distribution with NURBS

2017 ◽  
Vol 56 (28) ◽  
pp. 7990 ◽  
Author(s):  
Lien T. Vu ◽  
Chao-Chang A. Chen ◽  
Patrick Joi-Tsang Shum
Keyword(s):  
Contact Lens ◽  
Power Distribution ◽  
Optical Power ◽  
Lens Design

Chromatic Aberration and Optical Power of a Diffractive Bifocal Contact Lens

1992 ◽  
Vol 69 (10) ◽  
pp. 797-804 ◽  
Author(s):  
DAVID A. ATCHISON ◽  
MING YE ◽  
ARTHUR BRADLEY ◽  
MICHAEL J. COLLINS ◽  
XIAOXIAO ZHANG ◽  
...  
Keyword(s):  
Contact Lens ◽  
Optical Power ◽  
Chromatic Aberration

scholarly journals Fitting of a New Design of Full Scleral Contact Lens in Advanced Keratoconus with Previous Implantation of Intracorneal Ring Segments

2015 ◽  
Vol 4 (2) ◽  
pp. 56-59
Keyword(s):  
Visual Acuity ◽  
Contact Lens ◽  
Optical Power ◽  
Visual Quality ◽  
Limited Effect ◽  
Visual Rehabilitation ◽  
Ring Segment ◽  
Intracorneal Ring Segment ◽  
Topographic Pattern ◽  
Corneal Thinning

ABSTRACT This case report reports the visual rehabilitation obtained with the fitting of a new design of full scleral contact lens (ICD 16.5 contact lens, Paragon Vision Sciences, distributed by Lenticon, Madrid, Spain) in a cornea with advanced keratoconus and previous implantation of intracorneal ring segment with a very limited effect. This eye had a refraction of −3.00 × 55° cylinder, providing a visual acuity of 0.5 LogMAR. The topographic pattern was very irregular with the presence of a significant central protrusion and a significant central corneal thinning. Some previous unsuccessful fittings have been performed with corneal and corneal-scleral lenses. A comfortable wearing was achieved with a fully scleral contact lens of 4600 µm of sagittal height, optical power of −11.25 D, and providing an apical clearance of 196 µm. A visual acuity of 0.0 LogMAR combined with a relevant aberrometric improvement was achieved with this contact lens. The patient was completely satisfied with the fitting. The result was maintained during 1 year after the fitting. Full scleral lenses are then able to provide comfortable wear and a significant increase in visual acuity combined with a significant improvement in the visual quality in eyes with advanced keratoconus. How to cite this article Llorens DPP. Fitting of a New Design of Full Scleral Contact Lens in Advanced Keratoconus with Previous Implantation of Intracorneal Ring Segments. Int J Kerat Ect Cor Dis 2015;4(2):56-59.

Use of the Magnetostatic Analogue In Electromagnetic Lens Engineering

1970 ◽  
Vol 28 ◽  
pp. 360-361
Author(s):  
John W. Coleman
Keyword(s):  
Boundary Conditions ◽  
High Performance ◽  
Force Fields ◽  
Optical Design ◽  
Direct Conversion ◽  
Design Engineering ◽  
Design Data ◽  
Scalar Potentials ◽  
Geometric Elements ◽  
At Will

In the design engineering of high performance electromagnetic lenses, the direct conversion of electron optical design data into drawings for reliable hardware is oftentimes difficult, especially in terms of how to mount parts to each other, how to tolerance dimensions, and how to specify finishes. An answer to this is in the use of magnetostatic analytics, corresponding to boundary conditions for the optical design. With such models, the magnetostatic force on a test pole along the axis may be examined, and in this way one may obtain priority listings for holding dimensions, relieving stresses, etc..The development of magnetostatic models most easily proceeds from the derivation of scalar potentials of separate geometric elements. These potentials can then be conbined at will because of the superposition characteristic of conservative force fields.

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