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.

Bazanos Panteleimon, chemist - secondary education teacher