Looking at the world through a CD
About the project
This work firstly proposes a method for
introducing young students to spectroscopy and spectroscopic
analysis, and secondly, presents a simple construction which in
combination with a simple method allows to perform spectroscopic
measurements with an accuracy comparable to a traditional laboratory
spectrophotometer. Both strands of work based on the diffraction of
light through the optical disks (CDs, DVDs) allowing analysis and
drawing conclusions from it.
Using optical media (CDs and
DVDs), one can inexpensively and quickly construct simple
spectroscopes, for his own observations and studies. The purpose of
this work is to show the construction of such inexpensive
spectroscopes and their use in certain areas of science and
teaching.
The experiments and activities that can be done with
such spectroscopes are divided into three categories:
A. Kindergarten – Lower
Primary
In this category, proposed simple observations of
bright bodies through an optical disk. It can be seen the daylight
coming through the window, lighting lamps in a room, etc. Even field
observations can be done, such as observation of a street at night,
an illuminated shop, the moon, etc.
B. Upper Primary - High
School
In this category, proposed experiments and activities
related to the spectra of luminous bodies (classification), the
color of bodies and the identification of substances according the
light spectrum they emit. Students can observe the light of various
objects such as light lamps of various types, the light of a candle,
the light of a camping gas, etc. and try to find similarities and
differences. Even observing the spectra of colored bodies, one can
understand the perception of color. Finally knowing the spectrum of
standard bodies, students can discover the composition of complex
objects.
C. Applications in Chemistry
In the upper classes of
secondary education and first years of university, teaching chemistry
requires spectroscopy or facilitated by its use. A simple
spectrophotometer of zero value and accuracy comparable to that of a
classical laboratory spectrophotometer can be constructed from simple
materials and a camera to which it is adjusted.
Photographs of the spectra obtained by
this construction, are processed with the aim of an image editor
software (Gimp, Photoshop, etc.) and converted to FIT files. The
resulting files are imported in the program Fv (provided free by
NASA) and the spectral profiles are formed. Calculations on the
spectral profiles leads to the desired result.
