<s>
Sensors	B-Application
are	O
always	O
used	O
with	O
other	O
electronics	O
.	O
</s>
<s>
Sensors	B-Application
are	O
used	O
in	O
everyday	O
objects	O
such	O
as	O
touch-sensitive	O
elevator	O
buttons	O
(	O
tactile	B-Algorithm
sensor	I-Algorithm
)	O
and	O
lamps	O
which	O
dim	O
or	O
brighten	O
by	O
touching	O
the	O
base	O
,	O
and	O
in	O
innumerable	O
applications	O
of	O
which	O
most	O
people	O
are	O
never	O
aware	O
.	O
</s>
<s>
With	O
advances	O
in	O
micromachinery	O
and	O
easy-to-use	O
microcontroller	B-Architecture
platforms	O
,	O
the	O
uses	O
of	O
sensors	B-Application
have	O
expanded	O
beyond	O
the	O
traditional	O
fields	O
of	O
temperature	O
,	O
pressure	O
and	O
flow	O
measurement	O
,	O
for	O
example	O
into	O
MARG	B-Device
sensors	I-Device
.	O
</s>
<s>
Analog	O
sensors	B-Application
such	O
as	O
potentiometers	B-Device
and	O
force-sensing	B-Algorithm
resistors	I-Algorithm
are	O
still	O
widely	O
used	O
.	O
</s>
<s>
There	O
is	O
a	O
wide	O
range	O
of	O
other	O
sensors	B-Application
that	O
measure	O
chemical	O
and	O
physical	O
properties	O
of	O
materials	O
,	O
including	O
optical	B-Application
sensors	I-Application
for	O
refractive	O
index	O
measurement	O
,	O
vibrational	O
sensors	B-Application
for	O
fluid	O
viscosity	O
measurement	O
,	O
and	O
electro-chemical	O
sensors	B-Application
for	O
monitoring	O
pH	O
of	O
fluids	O
.	O
</s>
<s>
Some	O
sensors	B-Application
can	O
also	O
affect	O
what	O
they	O
measure	O
;	O
for	O
instance	O
,	O
a	O
room	O
temperature	O
thermometer	O
inserted	O
into	O
a	O
hot	O
cup	O
of	O
liquid	O
cools	O
the	O
liquid	O
while	O
the	O
liquid	O
heats	O
the	O
thermometer	O
.	O
</s>
<s>
Sensors	B-Application
are	O
usually	O
designed	O
to	O
have	O
a	O
small	O
effect	O
on	O
what	O
is	O
measured	O
;	O
making	O
the	O
sensor	O
smaller	O
often	O
improves	O
this	O
and	O
may	O
introduce	O
other	O
advantages	O
.	O
</s>
<s>
Technological	O
progress	O
allows	O
more	O
and	O
more	O
sensors	B-Application
to	O
be	O
manufactured	O
on	O
a	O
microscopic	O
scale	O
as	O
microsensors	B-Application
using	O
MEMS	B-Architecture
technology	O
.	O
</s>
<s>
In	O
most	O
cases	O
,	O
a	O
microsensor	B-Application
reaches	O
a	O
significantly	O
faster	O
measurement	O
time	O
and	O
higher	O
sensitivity	O
compared	O
with	O
macroscopic	O
approaches	O
.	O
</s>
<s>
Due	O
to	O
the	O
increasing	O
demand	O
for	O
rapid	O
,	O
affordable	O
and	O
reliable	O
information	O
in	O
today	O
's	O
world	O
,	O
disposable	O
sensors	B-Application
—	O
low-cost	O
and	O
easy‐to‐use	O
devices	O
for	O
short‐term	O
monitoring	O
or	O
single‐shot	O
measurements	O
—	O
have	O
recently	O
gained	O
growing	O
importance	O
.	O
</s>
<s>
Using	O
this	O
class	O
of	O
sensors	B-Application
,	O
critical	O
analytical	O
information	O
can	O
be	O
obtained	O
by	O
anyone	O
,	O
anywhere	O
and	O
at	O
any	O
time	O
,	O
without	O
the	O
need	O
for	O
recalibration	O
and	O
worrying	O
about	O
contamination	O
.	O
</s>
<s>
Most	O
sensors	B-Application
have	O
a	O
linear	O
transfer	O
function	O
.	O
</s>
<s>
Since	O
sensors	B-Application
cannot	O
replicate	O
an	O
ideal	O
transfer	O
function	O
,	O
several	O
types	O
of	O
deviations	O
can	O
occur	O
which	O
limit	O
sensor	O
accuracy	O
:	O
</s>
<s>
This	O
is	O
an	O
error	O
in	O
the	O
y-intercept	B-Algorithm
of	O
a	O
linear	O
transfer	O
function	O
.	O
</s>
<s>
Often	O
,	O
this	O
behavior	O
is	O
described	O
with	O
a	O
bode	B-Algorithm
plot	I-Algorithm
showing	O
sensitivity	O
error	O
and	O
phase	O
shift	O
as	O
a	O
function	O
of	O
the	O
frequency	O
of	O
a	O
periodic	O
input	O
signal	O
.	O
</s>
<s>
This	O
error	O
is	O
also	O
called	O
quantization	B-Algorithm
error	O
.	O
</s>
<s>
If	O
the	O
signal	O
is	O
monitored	O
digitally	O
,	O
the	O
sampling	B-Algorithm
frequency	I-Algorithm
can	O
cause	O
a	O
dynamic	O
error	O
,	O
or	O
if	O
the	O
input	O
variable	O
or	O
added	O
noise	O
changes	O
periodically	O
at	O
a	O
frequency	O
near	O
a	O
multiple	O
of	O
the	O
sampling	O
rate	O
,	O
aliasing	B-Error_Name
errors	O
may	O
occur	O
.	O
</s>
<s>
For	O
example	O
,	O
most	O
sensors	B-Application
are	O
influenced	O
by	O
the	O
temperature	O
of	O
their	O
environment	O
.	O
</s>
<s>
Systematic	O
errors	O
can	O
sometimes	O
be	O
compensated	O
for	O
by	O
means	O
of	O
some	O
kind	O
of	O
calibration	B-General_Concept
strategy	O
.	O
</s>
<s>
The	O
resolution	O
of	O
a	O
sensor	O
with	O
a	O
digital	O
output	O
is	O
usually	O
the	O
numerical	B-Architecture
resolution	I-Architecture
of	O
the	O
digital	O
output	O
.	O
</s>
<s>
The	O
resolution	O
is	O
related	O
to	O
the	O
precision	B-Architecture
with	O
which	O
the	O
measurement	O
is	O
made	O
,	O
but	O
they	O
are	O
not	O
the	O
same	O
thing	O
.	O
</s>
<s>
In	O
a	O
time-of-flight	B-Device
camera	I-Device
,	O
the	O
distance	O
resolution	O
is	O
usually	O
equal	O
to	O
the	O
standard	B-General_Concept
deviation	I-General_Concept
(	O
total	O
noise	O
)	O
of	O
the	O
signal	O
expressed	O
in	O
unit	O
of	O
length	O
.	O
</s>
<s>
For	O
example	O
,	O
most	O
sensors	B-Application
are	O
influenced	O
by	O
the	O
temperature	O
of	O
their	O
environment	O
.	O
</s>
<s>
Two	O
main	O
steps	O
are	O
involved	O
in	O
the	O
functioning	O
of	O
a	O
chemical	O
sensor	O
,	O
namely	O
,	O
recognition	O
and	O
transduction	B-Algorithm
.	O
</s>
<s>
Consequently	O
,	O
a	O
characteristic	O
physical	O
parameter	O
varies	O
and	O
this	O
variation	O
is	O
reported	O
by	O
means	O
of	O
an	O
integrated	O
transducer	B-Algorithm
that	O
generates	O
the	O
output	O
signal	O
.	O
</s>
<s>
In	O
biomedicine	O
and	O
biotechnology	O
,	O
sensors	B-Application
which	O
detect	O
analytes	O
thanks	O
to	O
a	O
biological	O
component	O
,	O
such	O
as	O
cells	O
,	O
protein	O
,	O
nucleic	O
acid	O
or	O
biomimetic	O
polymers	O
,	O
are	O
called	O
biosensors	O
.	O
</s>
<s>
The	O
encapsulation	O
of	O
the	O
biological	O
component	O
in	O
biosensors	O
,	O
presents	O
a	O
slightly	O
different	O
problem	O
that	O
ordinary	O
sensors	B-Application
;	O
this	O
can	O
either	O
be	O
done	O
by	O
means	O
of	O
a	O
semipermeable	O
barrier	O
,	O
such	O
as	O
a	O
dialysis	O
membrane	O
or	O
a	O
hydrogel	O
,	O
or	O
a	O
3D	O
polymer	O
matrix	O
,	O
which	O
either	O
physically	O
constrains	O
the	O
sensing	O
macromolecule	O
or	O
chemically	O
constrains	O
the	O
macromolecule	O
by	O
bounding	O
it	O
to	O
the	O
scaffold	O
.	O
</s>
<s>
Neuromorphic	O
sensors	B-Application
are	O
sensors	B-Application
that	O
physically	O
mimic	O
structures	O
and	O
functions	O
of	O
biological	O
neural	O
entities	O
.	O
</s>
<s>
One	O
example	O
of	O
this	O
is	O
the	O
event	B-Algorithm
camera	I-Algorithm
.	O
</s>
<s>
Metal	B-Architecture
–	I-Architecture
oxide	I-Architecture
–	I-Architecture
semiconductor	I-Architecture
(	O
MOS	O
)	O
technology	O
originates	O
from	O
the	O
MOSFET	B-Architecture
(	O
MOS	O
field-effect	O
transistor	O
,	O
or	O
MOS	B-Architecture
transistor	I-Architecture
)	O
invented	O
by	O
Mohamed	O
M	O
.	O
Atalla	O
and	O
Dawon	O
Kahng	O
in	O
1959	O
,	O
and	O
demonstrated	O
in	O
1960	O
.	O
</s>
<s>
MOSFET	B-Architecture
sensors	B-Application
(	O
MOS	O
sensors	B-Application
)	O
were	O
later	O
developed	O
,	O
and	O
they	O
have	O
since	O
been	O
widely	O
used	O
to	O
measure	O
physical	O
,	O
chemical	O
,	O
biological	O
and	O
environmental	O
parameters	O
.	O
</s>
<s>
A	O
number	O
of	O
MOSFET	B-Architecture
sensors	B-Application
have	O
been	O
developed	O
,	O
for	O
measuring	O
physical	O
,	O
chemical	O
,	O
biological	O
and	O
environmental	O
parameters	O
.	O
</s>
<s>
The	O
earliest	O
MOSFET	B-Architecture
sensors	B-Application
include	O
the	O
open-gate	O
field-effect	O
transistor	O
(	O
OGFET	O
)	O
introduced	O
by	O
Johannessen	O
in	O
1970	O
,	O
the	O
ion-sensitive	B-Algorithm
field-effect	I-Algorithm
transistor	I-Algorithm
(	O
ISFET	B-Algorithm
)	O
invented	O
by	O
Piet	O
Bergveld	O
in	O
1970	O
,	O
the	O
adsorption	O
FET	O
(	O
ADFET	O
)	O
patented	O
by	O
P.F.	O
</s>
<s>
Cox	O
in	O
1974	O
,	O
and	O
a	O
hydrogen-sensitive	O
MOSFET	B-Architecture
demonstrated	O
by	O
I	O
.	O
Lundstrom	O
,	O
M.S.	O
</s>
<s>
The	O
ISFET	B-Algorithm
is	O
a	O
special	O
type	O
of	O
MOSFET	B-Architecture
with	O
a	O
gate	O
at	O
a	O
certain	O
distance	O
,	O
and	O
where	O
the	O
metal	B-Algorithm
gate	I-Algorithm
is	O
replaced	O
by	O
an	O
ion-sensitive	O
membrane	O
,	O
electrolyte	O
solution	O
and	O
reference	O
electrode	O
.	O
</s>
<s>
The	O
ISFET	B-Algorithm
is	O
widely	O
used	O
in	O
biomedical	O
applications	O
,	O
such	O
as	O
the	O
detection	O
of	O
DNA	O
hybridization	O
,	O
biomarker	O
detection	O
from	O
blood	O
,	O
antibody	O
detection	O
,	O
glucose	O
measurement	O
,	O
pH	O
sensing	O
,	O
and	O
genetic	O
technology	O
.	O
</s>
<s>
By	O
the	O
mid-1980s	O
,	O
numerous	O
other	O
MOSFET	B-Architecture
sensors	B-Application
had	O
been	O
developed	O
,	O
including	O
the	O
gas	O
sensor	O
FET	O
(	O
GASFET	O
)	O
,	O
surface	O
accessible	O
FET	O
(	O
SAFET	O
)	O
,	O
charge	O
flow	O
transistor	O
(	O
CFT	O
)	O
,	O
pressure	O
sensor	O
FET	O
(	O
PRESSFET	O
)	O
,	O
chemical	B-Algorithm
field-effect	I-Algorithm
transistor	I-Algorithm
(	O
ChemFET	B-Algorithm
)	O
,	O
reference	B-Algorithm
ISFET	I-Algorithm
(	O
REFET	O
)	O
,	O
biosensor	O
FET	O
(	O
BioFET	O
)	O
,	O
enzyme-modified	O
FET	O
(	O
ENFET	O
)	O
and	O
immunologically	O
modified	O
FET	O
(	O
IMFET	O
)	O
.	O
</s>
<s>
MOS	B-Architecture
technology	I-Architecture
is	O
the	O
basis	O
for	O
modern	O
image	B-Algorithm
sensors	I-Algorithm
,	O
including	O
the	O
charge-coupled	B-Algorithm
device	I-Algorithm
(	O
CCD	O
)	O
and	O
the	O
CMOS	B-Device
active-pixel	B-Architecture
sensor	I-Architecture
(	O
CMOS	B-Architecture
sensor	I-Architecture
)	O
,	O
used	O
in	O
digital	B-Algorithm
imaging	I-Algorithm
and	O
digital	B-Device
cameras	I-Device
.	O
</s>
<s>
The	O
MOS	O
active-pixel	B-Architecture
sensor	I-Architecture
(	O
APS	O
)	O
was	O
developed	O
by	O
Tsutomu	O
Nakamura	O
at	O
Olympus	O
in	O
1985	O
.	O
</s>
<s>
The	O
CMOS	B-Device
active-pixel	B-Architecture
sensor	I-Architecture
was	O
later	O
developed	O
by	O
Eric	O
Fossum	O
and	O
his	O
team	O
in	O
the	O
early	O
1990s	O
.	O
</s>
<s>
MOS	O
image	B-Algorithm
sensors	I-Algorithm
are	O
widely	O
used	O
in	O
optical	O
mouse	O
technology	O
.	O
</s>
<s>
The	O
first	O
optical	O
mouse	O
,	O
invented	O
by	O
Richard	O
F	O
.	O
Lyon	O
at	O
Xerox	O
in	O
1980	O
,	O
used	O
a	O
5µm	O
NMOS	B-Algorithm
sensor	O
chip	O
.	O
</s>
<s>
Since	O
the	O
first	O
commercial	O
optical	O
mouse	O
,	O
the	O
IntelliMouse	B-Device
introduced	O
in	O
1999	O
,	O
most	O
optical	O
mouse	O
devices	O
use	O
CMOS	B-Architecture
sensors	I-Architecture
.	O
</s>
<s>
MOS	O
monitoring	O
sensors	B-Application
are	O
used	O
for	O
house	O
monitoring	O
,	O
office	O
and	O
agriculture	O
monitoring	O
,	O
traffic	O
monitoring	O
(	O
including	O
car	B-Application
speed	I-Application
,	O
traffic	O
jams	O
,	O
and	O
traffic	O
accidents	O
)	O
,	O
weather	O
monitoring	O
(	O
such	O
as	O
for	O
rain	O
,	O
wind	O
,	O
lightning	O
and	O
storms	O
)	O
,	O
defense	O
monitoring	O
,	O
and	O
monitoring	O
temperature	O
,	O
humidity	O
,	O
air	O
pollution	O
,	O
fire	O
,	O
health	O
,	O
security	O
and	O
lighting	O
.	O
</s>
<s>
MOS	O
gas	O
detector	B-Application
sensors	B-Application
are	O
used	O
to	O
detect	O
carbon	O
monoxide	O
,	O
sulfur	O
dioxide	O
,	O
hydrogen	O
sulfide	O
,	O
ammonia	O
,	O
and	O
other	O
gas	O
substances	O
.	O
</s>
<s>
Other	O
MOS	O
sensors	B-Application
include	O
intelligent	B-Algorithm
sensors	I-Algorithm
and	O
wireless	B-Architecture
sensor	I-Architecture
network	I-Architecture
(	O
WSN	B-Architecture
)	O
technology	O
.	O
</s>
