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

Anatomy of the Eyeball01:20

Anatomy of the Eyeball

7.6K
The eye is a spherical, hollow structure composed of three tissue layers. The outer layer — the fibrous tunic, comprises the sclera — a white structure — and the cornea, which is transparent. The sclera encompasses some of the ocular surface, most of which is not visible. However, the 'white of the eye' is distinctively visible in humans compared to other species. The cornea, a clear covering at the front of the eye, enables light penetration. The eye's middle...
7.6K
Nodal Analysis01:10

Nodal Analysis

1.2K
Nodal analysis is a fundamental method in electrical engineering used to simplify the process of circuit analysis. This method revolves around the concept of using node voltages as the primary variables for circuit analysis. The objective is to determine the voltage at each node in a circuit, which can then be used to find other quantities of interest, such as currents through specific components.
Consider, for instance, a simple circuit composed of three nodes and three resistors, as shown in...
1.2K
Accessory Structures of the Eye01:17

Accessory Structures of the Eye

1.9K
Optical perception, or vision, is an extraordinary sense dependent on converting light signals received via the ocular organs. These organs, known as eyes, are securely positioned within the bony cavities of the skull, called orbits. The orbits serve a dual purpose: a protective shield for the ocular globes and a stable attachment point for the soft ocular tissues. The eye's external protective mechanisms include the eyelids, which are edged with lashes that act as a barrier against foreign...
1.9K
Nodal Analysis with Voltage Sources01:11

Nodal Analysis with Voltage Sources

1.4K
Nodal analysis is a remarkably effective method used in electrical engineering to simplify the analysis of complex circuits, including those with dependent or independent voltage sources. Its strength lies in its systematic approach to breaking down circuits into manageable components, making it easier for engineers to understand and solve.
Consider a circuit that contains four resistors and two voltage sources, as shown in Figure 1. One of these voltage sources is connected between a...
1.4K
Muscles of the Eye01:20

Muscles of the Eye

2.1K
The muscles of the eye are sophisticated structures that control eye movement and focus, allowing for the precise and rapid adjustments necessary for vision. The human eye is controlled by ten muscles — six extraocular muscles, three intraocular muscles, and one primary eyelid retractor muscle.
Extraocular Muscles
The six extraocular muscles surround the eyeball and control its movements. They are responsible for a wide range of eye motions, including looking up, down, left, right, and...
2.1K
Focusing of Light in the Eye01:16

Focusing of Light in the Eye

3.3K
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...
3.3K

You might also read

Related Articles

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

Sort by
Same author

Relating intraocular lens tilt to the optical axes of the eye.

Journal of the Optical Society of America. A, Optics, image science, and vision·2026
Same author

Comment on: Optical confirmation by a thick-lens formula of the optimized A-constant (as calculated by a thin-lens formula) of a new intraocular lens.

Journal of cataract and refractive surgery·2025
Same author

Vignetting and peripheral double images with intraocular lenses.

Biomedical optics express·2025
Same author

Design concepts for advanced-technology intraocular lenses [Invited].

Biomedical optics express·2025
Same author

Optical modeling of the entire visual field of the eye.

Journal of the Optical Society of America. A, Optics, image science, and vision·2023
Same author

Focal length, EFL, and the eye.

Applied optics·2023
Same journal

Multifunctional reconfigurable terahertz metasurface based on vanadium dioxide phase transition: achieving broadband absorption and efficient polarization conversion.

Applied optics·2026
Same journal

High-Q-factor electromagnetically induced transparency utilizing quasi-bound states in the continuum in an all-dielectric terahertz metasurface.

Applied optics·2026
Same journal

Automated stitching interferometry for high-precision metrology of X-ray mirrors.

Applied optics·2026
Same journal

Experimental demonstration of an approach to designing a metal-dielectric DBR resonant cavity structure.

Applied optics·2026
Same journal

High-precision wavefront reconstruction from a single-shot interferogram using a physics-driven hybrid feature calibration network.

Applied optics·2026
Same journal

Ultra-high-Q Fano resonance based on coupled topological corner states in Kagome photonic crystals.

Applied optics·2026
See all related articles

Related Experiment Video

Updated: Sep 25, 2025

Author Spotlight: Exploring Press Needle Efficacy and Underlying Molecular Pathways
05:26

Author Spotlight: Exploring Press Needle Efficacy and Underlying Molecular Pathways

Published on: April 12, 2024

1.8K

Nodal points and the eye.

Michael J Simpson

    Applied Optics
    |April 26, 2022
    PubMed
    Summary
    This summary is machine-generated.

    Nodal points in optics are key for understanding how the eye focuses light. While historically thought to be where input and image angles match, ray tracing shows pupil center rays, not nodal rays, define optical properties.

    More Related Videos

    Ocular Kinematics Measured by In Vitro Stimulation of the Cranial Nerves in the Turtle
    10:49

    Ocular Kinematics Measured by In Vitro Stimulation of the Cranial Nerves in the Turtle

    Published on: June 2, 2018

    8.5K
    Optic Nerve Sheath Point of Care Ultrasound: Image Acquisition
    06:09

    Optic Nerve Sheath Point of Care Ultrasound: Image Acquisition

    Published on: August 18, 2023

    1.9K

    Related Experiment Videos

    Last Updated: Sep 25, 2025

    Author Spotlight: Exploring Press Needle Efficacy and Underlying Molecular Pathways
    05:26

    Author Spotlight: Exploring Press Needle Efficacy and Underlying Molecular Pathways

    Published on: April 12, 2024

    1.8K
    Ocular Kinematics Measured by In Vitro Stimulation of the Cranial Nerves in the Turtle
    10:49

    Ocular Kinematics Measured by In Vitro Stimulation of the Cranial Nerves in the Turtle

    Published on: June 2, 2018

    8.5K
    Optic Nerve Sheath Point of Care Ultrasound: Image Acquisition
    06:09

    Optic Nerve Sheath Point of Care Ultrasound: Image Acquisition

    Published on: August 18, 2023

    1.9K

    Area of Science:

    • Optics
    • Ophthalmology
    • Visual Science

    Background:

    • Nodal points, described by Listing in 1845, are crucial for optical system characterization.
    • Historically, nodal points were assumed to be where input and image angles in the eye converge.
    • The concept of nodal points is distinct from principal points, especially with refractive index differences.

    Purpose of the Study:

    • To clarify the precise optical role of nodal points in the human eye.
    • To investigate the validity of the assumption that input and image angles match at the nodal point for large angles.
    • To determine which ray bundles accurately define the eye's optical properties.

    Main Methods:

    • Review of historical definitions and usage of nodal points and nodal slides.
    • Analysis of raytrace calculations for light rays at various angles to the optical axis.
    • Examination of the geometric and refractive properties of the eye's optical components.

    Main Results:

    • Raytrace calculations confirm 1:1 angular scaling at large angles, but not solely due to nodal points.
    • The apparent matching of angles is influenced by corneal and retinal curvature and exit pupil rescaling.
    • Ray bundles passing through the pupil center, not paraxial nodal rays, are the primary determinants of optical properties.

    Conclusions:

    • The traditional understanding of nodal points' role in angular scaling within the eye requires refinement.
    • Corneal and retinal geometry, along with pupil effects, are critical factors in image formation.
    • Pupil center rays provide a more accurate representation of the eye's optical behavior than paraxial nodal rays.