000060989 001__ 60989
000060989 005__ 20190709135529.0
000060989 0247_ $$2doi$$a10.1364/OPTICA.4.000334
000060989 0248_ $$2sideral$$a98558
000060989 037__ $$aART-2017-98558
000060989 041__ $$aeng
000060989 100__ $$0(orcid)0000-0002-1328-1716$$aNavarro, R.
000060989 245__ $$aImpact of internal curvature gradient on the power and accommodation of the crystalline lens
000060989 260__ $$c2017
000060989 5060_ $$aAccess copy available to the general public$$fUnrestricted
000060989 5203_ $$aHuman crystalline lens has a layered, shell-like structure with the refractive index increasing from cortex to nucleus (gradient index or GRIN structure). Moreover, every iso-indicial layer has a certain curvature which also varies from cortex to nucleus, with a gradient of curvature (G). In the present manuscript, the role of G on the lens power is investigated along with its implications regarding the lens paradox (change of lens power with age) and intra-capsular accommodation mechanism (larger than expected changes of lens power during accommodation compared to a homogenous lens). To this end, a simplified formulation of paraxial lens power based on thin lens approximation is developed and applied to the anterior and posterior parts of the lens. The main theoretical result is that the power of both anterior and posterior lens is given by the sum of the power of a lens with a homogeneous refractive index equal to that of the nucleus and power associated with the contribution of the internal GRIN structure, which depends on G. This general result suggests that the sign of G is fundamental in increasing or decreasing the lens power.We found that the curvature gradient has a strong impact on lens power, helping to explain both the lens paradox and intra-capsular accommodation mechanism.
000060989 536__ $$9info:eu-repo/grantAgreement/EC/FP7/309416/EU/Signals for accommodative responses in humans/SACCO
000060989 540__ $$9info:eu-repo/semantics/openAccess$$aby$$uhttp://creativecommons.org/licenses/by/3.0/es/
000060989 590__ $$a7.536$$b2017
000060989 591__ $$aOPTICS$$b5 / 94 = 0.053$$c2017$$dQ1$$eT1
000060989 592__ $$a4.602$$b2017
000060989 593__ $$aElectronic, Optical and Magnetic Materials$$c2017$$dQ1
000060989 593__ $$aAtomic and Molecular Physics, and Optics$$c2017$$dQ1
000060989 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion
000060989 700__ $$aLópez-Gil, N.
000060989 773__ $$g4, 3 (2017), 334-340$$pOptica$$tOptica$$x2334-2536
000060989 8564_ $$s1352694$$uhttps://zaguan.unizar.es/record/60989/files/texto_completo.pdf$$yVersión publicada
000060989 8564_ $$s129372$$uhttps://zaguan.unizar.es/record/60989/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada
000060989 909CO $$ooai:zaguan.unizar.es:60989$$particulos$$pdriver
000060989 951__ $$a2019-07-09-12:01:21
000060989 980__ $$aARTICLE