Photon Energy Calculator

Calculate photon energy from wavelength or frequency. Essential for quantum optics, spectroscopy, and laser system design. Includes photon flux analysis and unit conversions.

ℹ️
Physics Note: Photon energy is fundamental to understanding laser interactions, absorption processes, and quantum efficiency in optical systems.

Input Parameters

Enter laser wavelength (common range: 200-20000 nm)
For photon flux calculation

Calculation Results

Photon Energy
1.165
eV
Photon Energy
1.87 × 10⁻¹⁹
J
Frequency
2.82 × 10¹⁴
Hz
Wave Number
9.40 × 10³
cm⁻¹
Photon Flux
5.35 × 10¹⁸
photons/s
Laser Type
Near-IR Laser

Physics Formulas

Photon Energy

E = hf = hc/λ
E = Photon energy (J or eV) h = Planck constant (6.626 × 10⁻³⁴ J·s) f = Frequency (Hz) c = Speed of light (2.998 × 10⁸ m/s) λ = Wavelength (m)

Photon Flux

Φ = P/E = Pλ/(hc)
Φ = Photon flux (photons/s) P = Laser power (W) E = Photon energy (J) λ = Wavelength (m)

Wave Number

k = 1/λ = f/c
k = Wave number (cm⁻¹) λ = Wavelength (cm) f = Frequency (Hz) c = Speed of light (cm/s)

Applications

Spectroscopy

Determine photon energies for spectroscopic analysis, absorption measurements, and molecular excitation studies.

Quantum Optics

Calculate single photon properties for quantum communication, cryptography, and quantum computing applications.

Photodetector Design

Optimize photodiode and photomultiplier performance based on photon energy and flux calculations.

Laser Safety

Assess photon energy levels for laser safety classification and exposure limit calculations.

Frequently Asked Questions

What is photon energy?

Photon energy is the energy carried by a single photon, directly proportional to its frequency and inversely proportional to its wavelength. It's fundamental in understanding light-matter interactions.

How do I convert between eV and Joules?

Use the conversion factor: 1 eV = 1.602 × 10⁻¹⁹ J. Electron volts are commonly used in atomic and molecular physics, while Joules are the SI unit.

What is photon flux?

Photon flux is the number of photons passing through a given area per unit time. It's calculated by dividing laser power by individual photon energy.

Why is wave number important?

Wave number (reciprocal wavelength) is widely used in spectroscopy and represents the number of wavelengths per unit length, making it useful for energy level calculations.