In this activity, we gained knowledge on the properties of different light sources.
We gathered the following light sources: 2 cellphone LCDs, incandescent light, stove, flourescent and sunlight. The emittance spectra of the said light sources were then obtained using a spectroradiometer. Results are shown below.
Emittance Spectra of two Cellphones
The spectra from the two cellphone displays are very similar. They have "peaks" in the reddish and greenish regions.
Emittance Spectra of a Flourescent Lamp
In the spectra, there are several distinct peaks. This may be the remnants of the spectrum of the elements inside the flourescent lamp.
Emittance Spectra of a Incandescent Lamp
This particular emittance suggest that the incandescent lamp is "broadband". That is, its spectra is made up of a large number of wavelengths as opposed to monochromatic light which only has one wavelength.
Emittance Spectra of a Stove
At high enough temperatures, a heated object will emit light. This spectra is from a heated stove. It is hard to interpret it since the peaks may represent noise.
Emittance Spectra of a Sunlight
The spectra of sunlight is also broadband since it is the combination visible light. However, the graph suggest that it contains more reddish-greenish light than blue light.
Next, we computed for the emittance spectrum of a blackbody radiator for temperatures in the range. A video below shows how the emittance spectrum varies as the temperature increases. With this, we will be able to identify the color that an object will emit given its temperature.
