This exhibit lets visitors examine the colors of light using colored filters and a prism. The prism breaks up a bream of white light and projects the resulting spectrum onto a screen. White light contains all the colors of the rainbow. The colored filters at this table contain dyes that can absorb certain colors of light and allow other colors to successfully pass through. Visitors place the filters in the path of the white light and observe how the spectrum changes.
The Light Island exhibit is made up of a light source that projects rays of incandescent white and colored lights. Using different types of lenses, mirrors, filters, prisms, and Plexiglas, visitors experiment with light to observe reflection, refraction, color mixing and separation, and other optical phenomena. Some activities that can be performed at this exhibit include: using lenses to observe that different wavelengths (colors) of light focus at slightly different places; using mirrors to reflect or bounce one color of light at another and observe the resulting mixture of light; using a prism to bend light in such a way as to observe all the colors of white light; and using colored filters to observe light absorption and transmission.
At the Light Palette computer exhibit visitors combine the three primary colors of light (red, blue, and green) in various combinations and the amounts to create a target color. Visitors control the color of the background screen and eight vertical strips that lie across it. Visitors are challenged to match the colors of the strips to the chosen background color. When the match is perfect, the strips will disappear. Mixing colored lights is different than mixing colored pigments. When equal amounts of red, blue and green pigments are mixed together a dark muddy brown color is formed. When equal amounts of red, blue and green lights are mixed together white light is formed.
As the name implies, the Lux Rota (rotating light) art work by Christian Schless enables visitors to manipulate a spinning, beam of red or blue light imposed upon a large black background. Visitors can change the frequency, how often the light patterns appear on the screen; the RPM (revolutions per minute), the number of times the light rotates in one minute; and the voltage, the amount of electricity or current being supplied (controls brightness of the light). By adjusting these three controls a variety of interesting patterns, that appear to be made up of many light beams, are formed from the single beam of light. This occurs because the exhibit is being powered by an alternating electrical current that turns on and off 120 times per second. At this exhibit however, the effect of the alternating current becomes visible. When the light beam is moved quickly past the eye, the fine divisions of light and dark that are going on and off 120 times per second, which were invisible before, are now spread out over the retina of the eye and have become visible.
Every gas, when excited by an electrical current, glows with a unique combination of colors and those colors form a distinct pattern. No two gases emit the same pattern when excited. Examining the spectrum of light a gas emits has helped researchers determine the makeup of different light sources, including stars like the Sun. This exhibit lets visitors examine the spectra of various gases by putting a charge through them and examining the glow through special diffraction grating that splits light into its components.