**Related to Public Lab spectrometer**

Spectrometer primer: http://publiclaboratory.org/tool/spectrometer

Public Lab spectrometer: http://publiclab.org/wiki/dsk

Using Spectral Workbench: http://publiclaboratory.org/wiki/spectral-workbench-usage

**General Information**

On building a spectrometer:

http://sci-toys.com/scitoys/scitoys/light/cd_spectroscope/spectroscope.html

http://www.swpc.noaa.gov/Curric_7-12/Activity_1.pdf

https://www.youtube.com/watch?v=--GnaivlF9Q

Spectrometry discussion across the web: http://publiclaboratory.org/notes/warren/8-27-2012/spectrometry-discussion-across-web

**Curriculum** (currently a work in progress)

What are the basic components of a spectroscope/spectrometer?
Light source, diffuse reflector (white 'dull' paper as a background), sample, interference (source, sample, environment, dispersion element, sensor) aperture/polarizing slot, dispersion element (CdRom, diffraction grating), and sensor (webcam).

What are the two different types of spectroscopy, and how does the usage of the spectroscope differ?
http://en.wikipedia.org/wiki/Fluorescence_spectroscopy
http://en.wikipedia.org/wiki/Absorption_spectroscopy

What is light?
"Visible light (commonly referred to simply as light) is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight." Light is a stream of photons, also called electromagnetic radiation, within the visible band in the electromagnetic spectrum. These photons carry energy and may be absorbed by substances causing an increase in the average random molecular energy (temperature) of the substance: this is why light feels warm. Particles passing through a specific area over time is known as a flux. Flux may be a count of individual photons or may be a summation of their contained energy.
http://en.wikipedia.org/wiki/Light

So what are photons?
A photon is an individual particle, massless and stable and with no electromagnetic charge, which carries an amount of energy. But this energy is quantized: it only exists as in integer multiples of a specific constant, known as plank's constant.
Photons move at the speed of light, about 3.0x10^-8 m/s, in a perfect vacuum, but slow down when travelling through other substances.
A photon vibrates perpendicular to it's path of travel with a frequency directly proportional to its energy. The path of the photon due to this regular vibration over time is sinusoidal: it may be graphed as a sine wave dependent on time. The integer multiple of the photon's energy IS the frequency: energy of a photon equals plank's constant times frequency.
The distance peak to peak of this vibration is the wavelength, and it is inversely proportional to the energy.
Higher energy photons vibrate faster and across a smaller distance: higher frequency and shorter wavelengths.
The Electromagnetic spectrum is a linear diagram of the various possible wavelengths of photons. The spectrum is broken up and named into smaller sections. We will be focusing on the piece of the spectrum corresponding to visible photons: the visible spectrum.
http://en.wikipedia.org/wiki/Photon
http://en.wikipedia.org/wiki/Electromagnetic_spectrum
Photons exhibit characteristics of a wave and also those of a particle: called wave-particle duality. They will 'bend' and transmit through substances like sound waves, but they will also be absorbed and reflected as individual particles. It's important that we can bend light to disperse it into component frequencies and absorb light (as particles) to collect and measure it in a sensor.

What creates the light (photons) in the first place?
Nuclear reactions in the sun
Gas Excitation of noble gasses
LASERs
Thermal radiation caused by the temperature of a lightbulb's filament

If light is transmitted at a small number of specific frequencies, why do we usually get entire spectrums of light, instead of specific frequencies like those created by a LASER?
Rayleigh scattering in the sun and atmosphere http://en.wikipedia.org/wiki/Rayleigh_scattering

How does the dispersion element bend (refract) the frequencies of the light beam, and why does it split (disperse) into a spectrum of colors?


http://en.wikipedia.org/wiki/Optics
http://en.wikipedia.org/wiki/Lens_(optics)
http://en.wikipedia.org/wiki/Refraction
http://en.wikipedia.org/wiki/Dispersion_(optics)
http://en.wikipedia.org/wiki/Fraunhofer_lines
http://en.wikipedia.org/wiki/Chromism
http://en.wikipedia.org/wiki/Chromaticity_diagram
http://en.wikipedia.org/wiki/Image_sensor
http://en.wikipedia.org/wiki/Bayer_filter
http://en.wikipedia.org/wiki/Exposure_(photography)