Machine Vision Cameras and The Electromagnetic Spectrum

Almost everything emits, reflects, or transmits someSpectrum.
kind of light. The Electromagnetic (EM) Spectrum isOptics
the measurement of the frequency range of EMThe field of optics usually describes the behavior of
radiation of an object. The frequency is measured invisible, infrared, and ultraviolet light; however because
wavelengths. The wavelength ranges can extendlight is an electromagnetic wave, analogous
from the size of an atom to thousands of kilometers.phenomena occur in X-rays, microwaves, radio
The long wavelengths are low frequency and are thewaves, and other forms of electromagnetic radiation.
Radio, Microwave, and Infrared waves. The shortOptics can thus be regarded as a sub-field of
wavelengths are the high frequency Ultraviolet, X-rayelectromagnetism.
and Gamma Rays. The Visible Spectrum, or OpticalCamera Vision
Spectrum, is the range of the ElectromagneticIn vision applications that use camera technology the
Spectrum that is visible by the human eye.optical fields of visible, infrared and ultraviolet are the
The Visible Spectrum has no clear boundaries frommost widely used, and with the implementation of
one color to the next but is generally described in thespecialized optics, filters, and lighting many solutions
following ranges:to imaging issues can be found. Infrared Radiation
Violet 380-450nm (*nanometers)(IR) is a wavelength longer than visible light but
Blue 450-495nmshorter than radio waves (750nm to 1nm). Ultraviolet
Green 495-570nm(UV) is shorter than visible light but longer than X-Ray
Yellow 570-590nm(400nm to 200nm Near UV, NUV). Most cameras will
Orange 590-620nmfall in the near IR or near UV range and with the use
Red 620-750nmof specialized lighting (LED's), enhancement of the
*Nanometer - a unit of length in the metric system,wavelengths is possible.
equal to one billionth of a meter, which is the currentInfrared (IR) camera technology is very common in
SI base unit of length. It can be written in scientificmilitary applications and Ultraviolet (UV) solutions are
notations as 1×10-9 m (engineering notation) orused in various machine vision, and industrial imaging
1 E-9 m (exponential notation), both meaning 1applications. There are also digital cameras, such as
1,000,000,000 metersFirewire 1394 which exploit the use of Ultraviolet
History(UV). Sony Electronics, Inc. offers the XCDSX910UV
Newton divided the spectrum into seven namedcamera featuring Firewire 1394, digital camera
colors: red, orange, yellow, green, blue, indigo, andtechnology. This camera is ideal for use in demanding
violet, or ROY G. BIV. Originally only five primarymarkets such as semiconductor inspection, ultraviolet
colors were named: red, yellow, green, blue andmicroscopy, FA precision inspection and surface
violet, but later he added indigo and orange to haveinspection applications.
seven colors. The need for the number seven wasHitachi Kokusai Electric Inc. offers the KP-F120, a
derived from the belief that it should match theNear IR (NIR), high resolution, progressive scan
number of known planets, number of days in a weekcamera with Camera Link, USB2.0, Firewire 1394 or
and the number of notes on a major scale. ThisLVDS digital camera interfaces. The spectral response
theory was derived from ancient Greek Sophistextends beyond 1000 nm. This camera is appropriate
philosophy.for a wide range of applications including machine
The word Spectrum is Latin for apparition, and wasvision, agricultural inspection, medical diagnostics and
coined by Newton during his experiments with light.research, and microscopy.
He observed that sunlight passing though a prismThere are many cameras that fall into the near
produced the apparition or spectrum or, in otherInfared (IR) and near Ultraviolet (UV) ranges. They
words, a band of colors.are used in a variety of applications and provide
Sir Isaac Newton wrote Optick,s released in 1704,many solutions from military to medical.
hailed as one of the earliest explanations of the