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

Dimensional Analysis01:23

Dimensional Analysis

Dimensional analysis is a powerful tool that is used in physics and engineering to understand and predict the behavior of physical systems. The basic idea behind dimensional analysis is to express physical quantities in terms of fundamental dimensions such as the mass, length, and time. Derived dimensions like the velocity, acceleration, and force are derived from the combinations of these fundamental dimensions.
Dimensional analysis allows us to analyze and compare physical quantities on a...
Dimensional Analysis02:19

Dimensional Analysis

The concept of dimension is important because every mathematical equation linking physical quantities must be dimensionally consistent, implying that mathematical equations must meet the following two rules. The first rule is that, in an equation, the expressions on each side of the equal sign must have the same dimensions. This is fairly intuitive since we can only add or subtract quantities of the same type (dimension). The second rule states that, in an equation, the arguments of any of the...
Dimensional Analysis03:40

Dimensional Analysis

Dimensional analysis, also known as the factor label method, is a versatile approach for mathematical operations. The main principle behind this approach is: the units of quantities must be subjected to the same mathematical operations as their associated numbers. This method can be applied to computations ranging from simple unit conversions to more complex and multi-step calculations involving several different quantities and their units.
Conversion Factors and Dimensional Analysis
The unit...
Dimensional Analysis01:27

Dimensional Analysis

Dimensional analysis is a valuable technique in fluid mechanics for simplifying complex problems by reducing them into dimensionless groups. These groups capture the essential relationships between the variables involved, allowing researchers and engineers to analyze fluid flow without dealing with each variable individually. This approach reduces the number of independent variables, allowing for easier analysis and better understanding of physical phenomena.
In fluid mechanics, dimensional...
Visual System01:26

Visual System

Light enters the eye through the cornea, a transparent, dome-shaped surface covering the surface of the eyeball that helps to direct and focus incoming light. This light is then channeled toward the pupil, an adjustable opening whose size is controlled by the iris. The iris, a pigmented muscle, regulates the amount of light entering the eye by contracting or dilating the pupil, thereby ensuring optimal light levels for clear vision.
Once through the pupil, the light passes through the lens, a...
Depth Perception and Spatial Vision01:15

Depth Perception and Spatial Vision

Depth perception is the ability to perceive objects three-dimensionally. It relies on two types of cues: binocular and monocular. Binocular cues depend on the combination of images from both eyes and how the eyes work together. Since the eyes are in slightly different positions, each eye captures a slightly different image. This disparity between images, known as binocular disparity, helps the brain interpret depth. When the brain compares these images, it determines the distance to an object.

You might also read

Related Articles

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

Sort by
Same author

Retinal Images with Catenary-Curved Contact Lenses [Letter].

Clinical ophthalmology (Auckland, N.Z.)·2025
Same author

Defocus degradation of retinal images in the Maxwellian view.

Journal of the Optical Society of America. A, Optics, image science, and vision·2025
Same author

Jay M. Enoch (1929-2025), Berkeley Optometry Dean and leading retina researcher: A biographical memoir of an important 20th-century vision researcher and optometric educator, by one of his contemporaries.

Optometry and vision science : official publication of the American Academy of Optometry·2025
Same author

Immanuel Kant's Schema of object perception and cognition.

Perception·2025
Same author

The concept of group and the theory of perception.

Vision research·2024
Same author

Retinal image quality for multifocal lenses with on- and off-axis annular zones.

Biomedical optics express·2024
Same journal

Multi-module collaborative optimization-driven fast speckle correlation imaging in variable environments.

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

Secrecy performance analysis of NOMA-UWOC systems over a vertically stratified WGG oceanic turbulence channel.

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

Backscattering of plane waves in a composite system containing a rough surface and anisotropic scatterers.

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

Aspherical surface construction methods based on extended Jacobi polynomials.

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

OCT sidelobe suppression method based on dual-path phase sinusoidal modulation and minimum value fusion.

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

Optical design concepts using wavelength-selective diffractive optics to enable miniaturized multimodal endoscopic imaging across separated spectral ranges.

Journal of the Optical Society of America. A, Optics, image science, and vision·2026
See all related articles

Related Experiment Video

Updated: Jun 16, 2026

Integrating Visual Psychophysical Assays within a Y-Maze to Isolate the Role that Visual Features Play in Navigational Decisions
07:09

Integrating Visual Psychophysical Assays within a Y-Maze to Isolate the Role that Visual Features Play in Navigational Decisions

Published on: May 2, 2019

Dimensional analysis of visual signals.

Gerald Westheimer1

  • 1Division of Neurobiology, 144 Life Sciences Addition, University of California, Berkeley, California 94720-3200, USA. gwestheimer@berkeley.edu

Journal of the Optical Society of America. A, Optics, Image Science, and Vision
|February 4, 2010
PubMed
Summary
This summary is machine-generated.

This study clarifies the physics of light measurement in vision. It distinguishes between energy and power, showing energy is for time-delimited stimuli, while power is for continuous excitation.

More Related Videos

A Psychophysics Paradigm for the Collection and Analysis of Similarity Judgments
08:12

A Psychophysics Paradigm for the Collection and Analysis of Similarity Judgments

Published on: March 1, 2022

Visualizing Visual Adaptation
04:43

Visualizing Visual Adaptation

Published on: April 24, 2017

Related Experiment Videos

Last Updated: Jun 16, 2026

Integrating Visual Psychophysical Assays within a Y-Maze to Isolate the Role that Visual Features Play in Navigational Decisions
07:09

Integrating Visual Psychophysical Assays within a Y-Maze to Isolate the Role that Visual Features Play in Navigational Decisions

Published on: May 2, 2019

A Psychophysics Paradigm for the Collection and Analysis of Similarity Judgments
08:12

A Psychophysics Paradigm for the Collection and Analysis of Similarity Judgments

Published on: March 1, 2022

Visualizing Visual Adaptation
04:43

Visualizing Visual Adaptation

Published on: April 24, 2017

Area of Science:

  • Vision science
  • Physics of light measurement
  • Photometry

Background:

  • The radiance-luminance parallelism is a classical concept in visual processing.
  • This parallelism is often modeled using physics and engineering principles.
  • The terms "energy" and "power" have specific meanings in physics related to flux over time.

Purpose of the Study:

  • To clarify the precise definitions and applications of "energy" and "power" in the context of visual stimuli.
  • To ensure dimensional consistency in physical models of vision.
  • To differentiate between time-delimited and continuous light stimuli measurements.

Main Methods:

  • Analysis of physical definitions of energy and power.
  • Application of dimensional analysis to visual stimuli.
  • Distinction between time-integrated flux (energy) and time rate of flux transfer (power).

Main Results:

  • "Energy" is appropriate for light stimuli with fixed durations.
  • "Power" is the correct term for the time rate of flux transfer in continuous excitation.
  • Physical models of vision require careful consideration of stimulus duration for accurate energy measurement.

Conclusions:

  • Accurate measurement of visual stimuli requires adherence to physical definitions of energy and power.
  • Models of visual processing should specify whether stimuli are time-delimited (energy) or continuous (power).
  • Dimensional correctness in physics-based vision models is crucial for accurate interpretation of light stimuli.