
78 Fundamentals of Sensors for Engineering and Science
blue
cones
green
cones
red
cones
rods
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550 600
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25
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violet
blue cyan green yellow orange
red
Percent Light Absorption
Wavelength (nm)
FIGURE 3.3
The visible spectrum and response curves for rods and cones. Parts adapted
from [1] and [2].
Taste receptors are on the surface of the tongue and in the mucosa of the
epiglottis, palate, and pharynx. There are three types of protuberances on
the tongue (papillae), each containing a different number of taste buds (from
approximately 5 to 100 taste buds per papilla). The sensory end of a taste
bud has microvilli that are located within a taste pore.