The Ocean Optics Spectrometer can be used to measure the spectrum of each fluorescent bulb. The Spectrometer is a small box attached to the computer with a fiber optic cable coming out of it. Spectra can be measured by starting up the SpectraSuite program on the computer and pointing the fiber optic cable at a light source.

  1. Turn on each of the bulbs on the light box and try to guess which bulb has the highest temperature based only on how it looks to your eyes.
     
  2. Observe the spectrum of each fluorescent bulb using the spectrometer. You will get the best results if you first set the boxcar width to 100 and the integration time to 25 milliseconds in the SpectraSuite program. The end of the fiber optic cable should point roughly at the light source, but can be up to a couple feet away and still get plenty of light. You may see a few narrow peaks at the short-wavelength end of the spectrum - these are artifacts and can be ignored.
lightbox

In this section, you will observe the different frequencies of light produced by three different flourescent light bulbs. Modern flourescents try to simulate daylight conditions by producing colors of various "temperatures". A flourescent bulb actually contains a mixture of electrically excited gases that produce light at a number of narrow frequencies. Our eyes, however, are poor spectrometers and thus perceive this light as "warm" or "cool" light.