# Photon Flux to Radiant Flux Calculator

### Converting Photon Energy from Wavelength

The energy of the photon $$E$$ can be be calculated using the equation $$E = {hc \over \lambda}$$. In this equation Planck's constant $$h$$ and the speed of light in vacuum $$c$$ are known values, so only the wavelength $$\lambda$$ is needed to calculate the energy.

### Converting Photon Flux $$photon \over {second}$$ to Radiant Flux $$W$$:

The Radiant Flux $$\Phi_e$$ is equal to the energy of the photon $$E$$ times the photon rate $$1\over second$$ $$\Phi_e = E \times {photon \over second}$$ This equation gives the Radiant Flux in units of $$Joule \over second$$ which is equivalent to $$Watt$$.

Wavelength

Photon Energy
$$J$$
Photon Rate
$$1 \over s$$