National Instruments PCI-1411 - Manual (Page 31)

© National Instruments Corporation B-1 IMAQ PCI/PXI-1411 User Manual
B
Introduction to Color
Color is the wavelength of the light we receive in our eye when we look at
an object. In theory, the color spectrum is infinite. Humans, however, can
see only a small portion of this spectrum—the portion that goes from the
red edge of infrared light (the longest wavelength) to the blue edge of
ultraviolet light (the shortest wavelength). This continuous spectrum is
called the visible spectrum, as shown in Figure B-1.
Figure B-1. White Light and the Visible Spectrum
White light is a combination of all colors at once. The spectrum of white
light is continuous and goes from ultraviolet to infrared in a smooth
transition. You can represent a good approximation of white light by
selecting a few reference colors and weighting them appropriately. The
most common way to represent white light is to use three reference
components, such as red, green, and blue (R, G, and B primaries). You can
simulate most colors of the visible spectrum using these primaries. For
example, video projectors use red, green, and blue light generators, and an
RGB camera uses red, green, and blue sensors.