Related Experiment Video
Updated: Jun 16, 2026
12:19
Measurement of Quantum Interference in a Silicon Ring Resonator Photon Source
Published on: April 4, 2017
Summary
Photon scalar irradiance (h) measures available light energy for photosynthesis. This study introduces a new measurement technique and calibration method for underwater photon scalar irradiance collectors.
Area of Science:
- Optics
- Oceanography
- Photosynthesis Research
Background:
- Photon scalar irradiance (h) quantifies light energy available for photosynthesis.
- Accurate measurement of underwater light is crucial for aquatic ecosystems.
- Existing methods may have limitations in capturing omnidirectional light.
Purpose of the Study:
- To define and justify photon scalar irradiance (h) as an optimal measure of radiant energy for photosynthesis.
- To present a novel technique for measuring photon scalar irradiance (h).
- To outline considerations for the absolute calibration of underwater photon scalar irradiance collectors.
Main Methods:
- Review of theoretical basis for photon scalar irradiance (h) in photosynthesis.
- Development of a new measurement apparatus for photon scalar irradiance (h).
- Description of calibration procedures for underwater collectors.
Main Results:
- Photon scalar irradiance (h) is proposed as a superior metric for photosynthetic light availability.
- A new technique for measuring photon scalar irradiance (h) has been developed.
- Methodology for absolute calibration of underwater collectors is detailed.
Conclusions:
- Photon scalar irradiance (h) provides a robust measure of light energy for photosynthesis.
- The new measurement technique facilitates more accurate assessment of underwater light.
- Standardized calibration is essential for reliable underwater photon scalar irradiance (h) data.
Related Concept Videos
02:26Photoelectric Effect
When light of a particular wavelength strikes a metal surface, electrons are emitted. This is called the photoelectric effect. The minimum frequency of light that can cause such emission of electrons is called the threshold frequency, which is specific to the metal. Light with a frequency lower than the threshold frequency, even if it is of high intensity, cannot initiate the emission of electrons. However, when the frequency is higher than the threshold value, the number of electrons ejected...
01:10Dual Nature of Electromagnetic (EM) Radiation
Electromagnetic (EM) radiation consists of electric and magnetic field components oscillating in planes perpendicular to each other and mutually perpendicular to radiation propagation through space. EM radiation can be classified as a wave, characterized by the properties of waves such as wavelength (denoted as λ) and frequency (represented by ν).
Wavelength is the distance between two consecutive peaks (the highest point) or troughs (the lowest point) in the wave. Frequency is the number of...
Wavelength is the distance between two consecutive peaks (the highest point) or troughs (the lowest point) in the wave. Frequency is the number of...
01:22Intensity Of Electromagnetic Waves
The energy transport per unit area per unit time, or the Poynting vector, gives the energy flux of an electromagnetic wave at any specific time. For a plane electromagnetic wave with E0 and B0 as the peak electric and magnetic fields and traveling along the x-axis, the time-varying energy flux can be given by the following equation:
02:39Emission Spectra
When solids, liquids, or condensed gases are heated sufficiently, they radiate some of the excess energy as light. Photons produced in this manner have a range of energies, and thereby produce a continuous spectrum in which an unbroken series of wavelengths is present.
01:12Interaction of EM Radiation with Matter: Spectroscopy
Electromagnetic (EM) radiation can be considered an oscillating electric and magnetic field propagating through a medium that can interact with matter in its path. The electric field in the radiation can interact with electrical charges in the atoms or molecules in the matter. On the other hand, the magnetic field can interact with the magnetic field in the atomic nucleus. The study of the interaction between electromagnetic radiation and matter is termed spectroscopy. Spectroscopy is the study...
01:21Introduction to Scalars
Many familiar physical quantities can be specified completely by giving a single number and the appropriate unit. For example, "a class period lasts 50 min," or "the gas tank in my car holds 65 L," or "the distance between the two posts is 100 m." A physical quantity that can be specified completely in this manner is called a scalar quantity. The word "scalar" is a synonym for "number." Time, mass, distance, length, volume, temperature, and energy are some examples of scalar quantities.
Scalar...
Scalar...