Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Focusing of Light in the Eye01:16

Focusing of Light in the Eye

Light rays enter the eye through the cornea, a transparent dome-shaped tissue that is the eye's outermost layer. The cornea bends or refracts, light rays traveling to the pupil. The shape of the cornea determines how much of the light is bent and whether the image will be focused correctly on the retina at the back of the eye. Once the light has passed through both refraction layers, it converges into a single focal point onto a small area. This is where photoreceptors start transforming...
Imperfections in Crystal Structure: Point, Line and Plane Defects01:25

Imperfections in Crystal Structure: Point, Line and Plane Defects

A perfect crystal, in theory, has a uniform structure with the same unit cell and lattice points throughout. However, any deviation from this periodic arrangement is known as an imperfection or defect. These defects can be categorized into three types: point, line, and plane defects.Point defects occur when there is a deviation from the ideal due to missing atoms, displaced atoms, or additional atoms. These imperfections might occur due to imperfect packing during crystallization or because of...
Determination of Crystal Structures01:29

Determination of Crystal Structures

In the late 1800s, the revelation that light extended beyond visible wavelengths led to the discovery of X-rays by Wilhelm Roentgen. Recognized as high-energy electromagnetic radiation with short wavelengths, X-rays prompted exploration into their interaction with crystals. Max von Laue proposed in 1912 that the periodic arrangement of atoms, ions, or molecules in crystals would cause them to diffract X-rays, a hypothesis confirmed through experiments with copper sulfate and zinc sulfide...
Law of Rational Indices01:29

Law of Rational Indices

The Law of rational indices is a fundamental principle in the field of crystallography. According to this law, the intercepts of a crystal face along the crystallographic axes (the three-dimensional axes along which a crystal is measured) can be expressed as either equivalent to the unit intercepts (a, b, c) or simple whole number multiples of them. These multiples are typically denoted as na, n'b, and n''c, where n, n', and n'' are simple whole numbers.To illustrate, consider a crystal with...
X-ray Crystallography02:18

X-ray Crystallography

The size of the unit cell and the arrangement of atoms in a crystal may be determined from measurements of the diffraction of X-rays by the crystal, termed X-ray crystallography.
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
Imperfections in Crystal Structure: Stoichiometric Point Defects01:26

Imperfections in Crystal Structure: Stoichiometric Point Defects

Schottky defects arise when some lattice points in a crystal, such as those in NaCl, remain unoccupied, creating lattice vacancies without disturbing the overall electrical neutrality of the crystal. This defect is common in ionic crystals where the positive and negative ions are similar in size, as seen in sodium chloride and cesium chloride. The presence of Schottky defects enables the crystal to conduct electricity to a small extent through an ionic mechanism. Electric fields cause nearby...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Acceleration of Myopic Shifts in Refraction and Axial Elongation Begins in the Premyopia Stage.

Investigative ophthalmology & visual science·2025
Same author

Atropine or Cyclopentolate to Diagnose Premyopia in Preschool Children.

JAMA ophthalmology·2025
Same author

Ocular Risks of Topical Atropine Prescriptions Among Taiwanese Children.

JAMA ophthalmology·2025
Same author

Ocular and vision development during childhood: Insights from a large prospective cohort study in Chinese children.

Acta ophthalmologica·2025
Same author

Effectiveness of bright light therapy and combination with myopic defocus for controlling myopic eye growth in schoolchildren: study protocol for a randomised controlled trial (phase 1).

BMJ open ophthalmology·2025
Same author

Changes in Lens Thickness and Power Before and After Myopia Onset.

Investigative ophthalmology & visual science·2025

Related Experiment Video

Updated: May 26, 2026

Comparison of Agreement and Accuracy using Binocular Wavefront Optometer with Autorefractor and Phoropter
05:14

Comparison of Agreement and Accuracy using Binocular Wavefront Optometer with Autorefractor and Phoropter

Published on: September 16, 2025

Crystalline lens power and refractive error.

Rafael Iribarren1, Ian G Morgan, Vinay Nangia

  • 1Department of Ophthalmology, San Luis Medical Center, Buenos Aires, Argentina.

Investigative Ophthalmology & Visual Science
|December 27, 2011
PubMed
Summary

Refractive error in adults over 50 is mainly influenced by axial length and crystalline lens power. Nuclear lens opacity also plays a role, with lens thickness and anterior chamber depth having minor effects.

More Related Videos

Subjective Refraction Test Using a Smartphone for Vision Screening
05:36

Subjective Refraction Test Using a Smartphone for Vision Screening

Published on: October 18, 2024

Sequential Application of Glass Coverslips to Assess the Compressive Stiffness of the Mouse Lens: Strain and Morphometric Analyses
07:56

Sequential Application of Glass Coverslips to Assess the Compressive Stiffness of the Mouse Lens: Strain and Morphometric Analyses

Published on: May 3, 2016

Related Experiment Videos

Last Updated: May 26, 2026

Comparison of Agreement and Accuracy using Binocular Wavefront Optometer with Autorefractor and Phoropter
05:14

Comparison of Agreement and Accuracy using Binocular Wavefront Optometer with Autorefractor and Phoropter

Published on: September 16, 2025

Subjective Refraction Test Using a Smartphone for Vision Screening
05:36

Subjective Refraction Test Using a Smartphone for Vision Screening

Published on: October 18, 2024

Sequential Application of Glass Coverslips to Assess the Compressive Stiffness of the Mouse Lens: Strain and Morphometric Analyses
07:56

Sequential Application of Glass Coverslips to Assess the Compressive Stiffness of the Mouse Lens: Strain and Morphometric Analyses

Published on: May 3, 2016

Area of Science:

  • Ophthalmology
  • Optometry
  • Vision Science

Background:

  • Refractive error is a significant cause of visual impairment globally.
  • Understanding the factors contributing to refractive error is crucial for developing effective interventions.
  • Nuclear cataract is a common age-related ocular condition affecting lens clarity and refractive properties.

Purpose of the Study:

  • To investigate the associations between crystalline lens refractive power, overall refractive error, and the severity of nuclear cataract.
  • To identify the primary determinants of refractive error in an aging population.

Main Methods:

  • A population-based study including 1885 phakic participants aged 50+ years.
  • Refractive lens power calculated using Bennett's formula, incorporating refractive error, corneal power, anterior chamber depth, lens thickness, and axial length.
  • Statistical analysis including correlation and multivariate analysis to determine significant associations.

Main Results:

  • Crystalline lens power and nuclear lens opacity grade showed the strongest associations with ocular refractive error (β = -0.41 and β = -0.42, respectively).
  • Axial length was also a significant factor (β = -0.35).
  • Multivariate analysis revealed significant associations between refractive error and axial length, refractive lens power, corneal refractive power, lens thickness, anterior chamber depth, and nuclear lens opacity.

Conclusions:

  • Axial length and crystalline lens refractive power are the predominant factors influencing refractive error variations in individuals aged 50 and above.
  • Corneal refractive power contributes to a lesser extent, while lens thickness and anterior chamber depth have minor influences.
  • Lens thickness was found to be significantly lower in eyes with greater nuclear opacity.