Page 45 - Sensors and Control Systems in Manufacturing

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Cha p te r

the advancement in 2008. However, in 1984, Fujio Masuoka, Prof. of
Solid State Electronics at Tohuku University in Sendai, Japan named
this breakthrough “flash” since its erasures of data in the device is
reminiscent of a camera flash. Today, flash has become one of the
most widely used memory systems in devices such as USB drives,
digital camera memory cards, and stand-alone chips in circuit boards.
However, with a set of recent advancements, flash memory is poised
to make an even greater impact on electronic devices.
The building block on which sensors and control technology is
erected is the clear understanding of light energy, and the methodol-
ogy of light generated and employed in making sensor devices.
Therefore, a clear understanding of light-emitting diodes (LEDs),
light amplification by stimulated emission of radiation (laser), the
visible light of through beams, infrared light energy, and ultraviolet
light energy will enhance the application of sensors and control sys-
tems in manufacturing applications.

1.8 Chromaticity—Color Rendering Index (CRI)
Chromaticity describes the lamp itself, or a neutral surface illuminated
by a lamp. Chromaticity sets the “tone” or atmosphere of an environ-
ment: warm or cool. Chromaticity is often called color temperature
and is usually measured in Kelvins. It can also be defined by using x
and y coordinates against a standard chromaticity scale developed by
the Commission Internationale de l’Éclairage (CIE).
An RGB color space is any additive color space based on the RGB
color model. A particular RGB color space is defined by the three chro-
maticity of the red, green, and blue additive primaries, and can pro-
duce any chromaticity that is the triangle defined by those primary
colors (Fig. 1.6). The complete specification of an RGB color space also
requires a white point chromaticity and a gamma correction curve.
RGB is an acronym for Red, Green, Blue.
An RGB color space can be easily understood by thinking of it as
“all possible colors” that can be made from three colorants for red,
green and blue. Imagine, for example, shining three lights together
onto a white wall: one red light, one green light, and one blue light,
each with dimmer switches. If only the red light is on, the wall will
look red. If only the green light is on, the wall will look green. If the
red and green lights are on together, the wall will look yellow. Dim
the red light some and the wall will become more of a yellow-green.
Dim the green light instead, and the wall will become more orange.
Bringing up the blue light a bit will cause the orange to become less
saturated and more whitish. In all, each setting of the three dimmer
switches will produce a different result, either in color or in bright-
ness or both. The set of all possible results is the gamut defined by
those particular color light bulbs. Swap out the red light bulb for one