<s>
Optical	B-General_Concept
sorting	I-General_Concept
(	O
sometimes	O
called	O
digital	B-General_Concept
sorting	I-General_Concept
)	O
is	O
the	O
automated	O
process	O
of	O
sorting	B-Algorithm
solid	O
products	O
using	O
cameras	O
and/or	O
lasers	O
.	O
</s>
<s>
Depending	O
on	O
the	O
types	O
of	O
sensors	O
used	O
and	O
the	O
software-driven	O
intelligence	O
of	O
the	O
image	B-Algorithm
processing	I-Algorithm
system	O
,	O
optical	O
sorters	O
can	O
recognize	O
objects	O
 '	O
color	O
,	O
size	O
,	O
shape	O
,	O
structural	O
properties	O
and	O
chemical	O
composition	O
.	O
</s>
<s>
Optical	B-General_Concept
sorting	I-General_Concept
achieves	O
non-destructive	O
,	O
100	O
percent	O
inspection	O
in-line	O
at	O
full	O
production	O
volumes	O
.	O
</s>
<s>
Compared	O
to	O
manual	O
sorting	B-Algorithm
,	O
which	O
is	O
subjective	O
and	O
inconsistent	O
,	O
optical	B-General_Concept
sorting	I-General_Concept
helps	O
improve	O
product	O
quality	O
,	O
maximize	O
throughput	O
and	O
increase	O
yields	O
while	O
reducing	O
labor	O
costs	O
.	O
</s>
<s>
Optical	B-General_Concept
sorting	I-General_Concept
is	O
an	O
idea	O
that	O
first	O
came	O
out	O
of	O
the	O
desire	O
to	O
automate	O
industrial	O
sorting	B-Algorithm
of	O
agricultural	O
goods	O
like	O
fruits	O
and	O
vegetables	O
.	O
</s>
<s>
Before	O
automated	O
optical	B-General_Concept
sorting	I-General_Concept
technology	O
was	O
conceived	O
in	O
the	O
1930s	O
,	O
companies	O
like	O
Unitec	O
were	O
producing	O
wooden	O
machinery	O
to	O
assist	O
in	O
the	O
mechanical	O
sorting	B-Algorithm
of	O
fruit	O
processing	O
.	O
</s>
<s>
In	O
1931	O
,	O
a	O
company	O
known	O
as	O
“	O
the	O
Electric	O
Sorting	B-Algorithm
Company	O
”	O
was	O
incorporated	O
and	O
began	O
the	O
creation	O
of	O
the	O
world	O
’s	O
first	O
color	O
sorters	O
,	O
which	O
were	O
being	O
installed	O
and	O
used	O
in	O
Michigan	O
’s	O
bean	O
industry	O
by	O
1932	O
.	O
</s>
<s>
In	O
1937	O
,	O
optical	B-General_Concept
sorting	I-General_Concept
technology	O
had	O
advanced	O
to	O
allow	O
for	O
systems	O
based	O
on	O
a	O
two-color	O
principle	O
of	O
selection	O
.	O
</s>
<s>
The	O
next	O
few	O
decades	O
saw	O
the	O
installation	O
of	O
new	O
and	O
improved	O
sorting	B-Algorithm
mechanisms	O
,	O
like	O
gravity	O
feed	O
systems	O
and	O
the	O
implementation	O
of	O
optical	B-General_Concept
sorting	I-General_Concept
in	O
more	O
agricultural	O
industries	O
.	O
</s>
<s>
In	O
the	O
late	O
1960s	O
,	O
optical	B-General_Concept
sorting	I-General_Concept
began	O
to	O
be	O
implemented	O
to	O
new	O
industries	O
beyond	O
agriculture	O
,	O
like	O
the	O
sorting	B-Algorithm
of	O
ferrous	O
and	O
non-ferrous	O
metals	O
.	O
</s>
<s>
By	O
the	O
1990s	O
,	O
optical	B-General_Concept
sorting	I-General_Concept
was	O
being	O
used	O
heavily	O
in	O
the	O
sorting	B-Algorithm
of	O
solid	O
wastes	O
.	O
</s>
<s>
Today	O
,	O
optical	B-General_Concept
sorting	I-General_Concept
is	O
used	O
in	O
a	O
wide	O
variety	O
of	O
industries	O
and	O
,	O
as	O
such	O
,	O
is	O
implemented	O
with	O
a	O
varying	O
selection	O
of	O
mechanisms	O
to	O
assist	O
in	O
that	O
specific	O
sorter	O
’s	O
task	O
.	O
</s>
<s>
In	O
general	O
,	O
optical	O
sorters	O
feature	O
four	O
major	O
components	O
:	O
the	O
feed	O
system	O
,	O
the	O
optical	O
system	O
,	O
image	B-Algorithm
processing	I-Algorithm
software	O
,	O
and	O
the	O
separation	O
system	O
.	O
</s>
<s>
The	O
image	B-Algorithm
processing	I-Algorithm
system	O
compares	O
objects	O
to	O
user-defined	O
accept/reject	O
thresholds	O
to	O
classify	O
objects	O
and	O
actuate	O
the	O
separation	O
system	O
.	O
</s>
<s>
Monochromatic	O
cameras	O
detect	O
shades	O
of	O
gray	O
from	O
black	O
to	O
white	O
and	O
can	O
be	O
effective	O
when	O
sorting	B-Algorithm
products	O
with	O
high-contrast	O
defects	O
.	O
</s>
<s>
Driven	O
by	O
the	O
need	O
to	O
solve	O
previously	O
impossible	O
sorting	B-Algorithm
challenges	O
,	O
a	O
new	O
generation	O
of	O
sorters	O
that	O
feature	O
multispectral	O
and	O
hyperspectral	B-Application
imaging	I-Application
systems	O
are	O
being	O
developed	O
.	O
</s>
<s>
Like	O
trichromatic	O
cameras	O
,	O
multispectral	O
and	O
hyperspectral	B-Application
cameras	I-Application
collect	O
data	O
from	O
the	O
electromagnetic	O
spectrum	O
.	O
</s>
<s>
Unlike	O
trichromatic	O
cameras	O
,	O
which	O
divide	O
light	O
into	O
three	O
bands	O
,	O
hyperspectral	B-Application
systems	O
can	O
divide	O
light	O
into	O
hundreds	O
of	O
narrow	O
bands	O
over	O
a	O
continuous	O
range	O
that	O
covers	O
a	O
vast	O
portion	O
of	O
the	O
electromagnetic	O
spectrum	O
.	O
</s>
<s>
Compared	O
to	O
the	O
three	O
data	O
points	O
per	O
pixel	O
collected	O
by	O
trichromatic	O
cameras	O
,	O
hyperspectral	B-Application
cameras	I-Application
can	O
collect	O
hundreds	O
of	O
data	O
points	O
per	O
pixel	O
,	O
which	O
are	O
combined	O
to	O
create	O
a	O
unique	O
spectral	O
signature	O
(	O
also	O
called	O
a	O
fingerprint	O
)	O
for	O
each	O
object	O
.	O
</s>
<s>
When	O
complemented	O
by	O
capable	O
software	O
intelligence	O
,	O
a	O
hyperspectral	B-Application
sorter	O
processes	O
those	O
fingerprints	O
to	O
enable	O
sorting	B-Algorithm
on	O
the	O
chemical	O
composition	O
of	O
the	O
product	O
.	O
</s>
<s>
Once	O
the	O
sensors	O
capture	O
the	O
object	O
's	O
response	O
to	O
the	O
energy	O
source	O
,	O
image	B-Algorithm
processing	I-Algorithm
is	O
used	O
to	O
manipulate	O
the	O
raw	O
data	O
.	O
</s>
<s>
The	O
image	B-Algorithm
processing	I-Algorithm
extracts	O
and	O
categorizes	O
information	O
about	O
specific	O
features	O
.	O
</s>
<s>
The	O
art	O
and	O
science	O
of	O
image	B-Algorithm
processing	I-Algorithm
lies	O
in	O
developing	O
algorithms	O
that	O
maximize	O
the	O
effectiveness	O
of	O
the	O
sorter	O
while	O
presenting	O
a	O
simple	O
user-interface	O
to	O
the	O
operator	O
.	O
</s>
<s>
Some	O
of	O
these	O
advancements	O
enhance	O
the	O
effectiveness	O
of	O
sorters	O
to	O
achieve	O
better	O
results	O
while	O
others	O
enable	O
completely	O
new	O
sorting	B-Algorithm
decisions	O
to	O
be	O
made	O
.	O
</s>
<s>
Belt	O
sorting	B-Algorithm
platforms	O
are	O
often	O
preferred	O
for	O
higher	O
capacity	O
applications	O
such	O
as	O
vegetable	O
and	O
potato	O
products	O
prior	O
to	O
canning	O
,	O
freezing	O
or	O
drying	O
.	O
</s>
<s>
These	O
sorters	O
can	O
either	O
be	O
designed	O
to	O
achieve	O
traditional	O
two-way	O
sorting	B-Algorithm
or	O
three-way	O
sorting	B-Algorithm
if	O
two	O
ejector	O
systems	O
with	O
three	O
outfeed	O
streams	O
are	O
equipped	O
.	O
</s>
<s>
A	O
fifth	O
type	O
of	O
sorting	B-Algorithm
platform	O
,	O
called	O
an	O
automated	O
defect	O
removal	O
(	O
ADR	O
)	O
system	O
,	O
is	O
specifically	O
for	O
potato	O
strips	O
(	O
French	O
fries	O
)	O
.	O
</s>
<s>
The	O
combination	O
of	O
an	O
ADR	O
system	O
followed	O
by	O
a	O
mechanical	O
nubbin	O
grader	O
is	O
another	O
type	O
of	O
optical	B-General_Concept
sorting	I-General_Concept
system	O
because	O
it	O
uses	O
optical	O
sensors	O
to	O
identify	O
and	O
remove	O
defects	O
.	O
</s>
<s>
For	O
products	O
that	O
require	O
sorting	B-Algorithm
only	O
by	O
size	O
,	O
mechanical	O
grading	O
systems	O
are	O
used	O
because	O
sensors	O
and	O
image	B-Algorithm
processing	I-Algorithm
software	O
is	O
not	O
necessary	O
.	O
</s>
<s>
These	O
mechanical	O
grading	O
systems	O
are	O
sometimes	O
referred	O
to	O
as	O
sorting	B-Algorithm
systems	O
,	O
but	O
should	O
not	O
be	O
confused	O
with	O
optical	O
sorters	O
that	O
feature	O
sensors	O
and	O
image	B-Algorithm
processing	I-Algorithm
systems	O
.	O
</s>
<s>
Optical	B-General_Concept
sorting	I-General_Concept
machines	O
can	O
be	O
used	O
to	O
identify	O
and	O
discard	O
manufacturing	O
waste	O
,	O
such	O
as	O
metals	O
,	O
drywall	O
,	O
cardboard	O
,	O
and	O
various	O
plastics	O
.	O
</s>
<s>
In	O
the	O
metal	O
industry	O
,	O
optical	B-General_Concept
sorting	I-General_Concept
machines	O
are	O
used	O
to	O
discard	O
plastics	O
,	O
glass	O
,	O
wood	O
,	O
and	O
other	O
non-needed	O
metals	O
.	O
</s>
<s>
The	O
plastic	O
industry	O
uses	O
optical	B-General_Concept
sorting	I-General_Concept
machines	O
to	O
not	O
only	O
discard	O
various	O
materials	O
like	O
those	O
listed	O
,	O
but	O
also	O
different	O
types	O
of	O
plastics	O
.	O
</s>
<s>
Optical	B-General_Concept
sorting	I-General_Concept
machines	O
discard	O
different	O
types	O
of	O
plastics	O
by	O
distinguishing	O
resin	O
types	O
.	O
</s>
<s>
Resin	O
types	O
that	O
optical	B-General_Concept
sorting	I-General_Concept
machines	O
can	O
identify	O
are	O
:	O
HDPE	O
,	O
PVC	O
,	O
PLA	O
,	O
PE	O
,	O
and	O
others	O
.	O
</s>
<s>
Optical	B-General_Concept
sorting	I-General_Concept
also	O
aids	O
in	O
recycling	O
since	O
the	O
discarded	O
materials	O
are	O
stored	O
in	O
bins	O
.	O
</s>
<s>
Optical	B-General_Concept
sorting	I-General_Concept
machines’	O
ability	O
to	O
distinguish	O
between	O
resin	O
types	O
also	O
aids	O
in	O
the	O
process	O
of	O
plastic	O
recycling	O
because	O
there	O
are	O
different	O
methods	O
used	O
for	O
each	O
plastic	O
type	O
.	O
</s>
<s>
In	O
the	O
coffee	O
industry	O
,	O
optical	B-General_Concept
sorting	I-General_Concept
machines	O
are	O
used	O
to	O
identify	O
and	O
remove	O
underdeveloped	O
coffee	O
beans	O
called	O
quakers	O
;	O
quakers	O
are	O
beans	O
that	O
contain	O
mostly	O
carbohydrates	O
and	O
sugars	O
.	O
</s>
<s>
Some	O
coffee	O
companies	O
like	O
Counter	O
Culture	O
use	O
these	O
machines	O
in	O
addition	O
to	O
pre-existing	O
sorting	B-Algorithm
methods	O
in	O
order	O
to	O
create	O
a	O
better	O
tasting	O
cup	O
of	O
coffee	O
.	O
</s>
<s>
However	O
,	O
this	O
science	O
is	O
not	O
limited	O
to	O
coffee	O
beans	O
;	O
food	O
items	O
such	O
as	O
mustard	O
seeds	O
,	O
fruits	O
,	O
wheat	O
,	O
and	O
hemp	O
can	O
all	O
be	O
processed	O
through	O
optical	B-General_Concept
sorting	I-General_Concept
machines	O
.	O
</s>
<s>
Grape	O
sorting	B-Algorithm
is	O
used	O
to	O
ensure	O
no	O
unripe/green	O
parts	O
to	O
the	O
plant	O
are	O
involved	O
in	O
the	O
wine	O
making	O
process	O
.	O
</s>
<s>
In	O
the	O
past	O
,	O
manual	O
sorting	B-Algorithm
via	O
sorting	B-Algorithm
tables	O
was	O
used	O
to	O
separate	O
the	O
defective	O
grapes	O
from	O
the	O
more	O
effective	O
grapes	O
.	O
</s>
<s>
Now	O
,	O
mechanical	O
harvesting	O
provides	O
a	O
higher	O
effectiveness	O
rate	O
compared	O
to	O
manual	O
sorting	B-Algorithm
.	O
</s>
<s>
At	O
different	O
points	O
in	O
the	O
line	O
,	O
materials	O
are	O
sorted	O
out	O
via	O
several	O
optical	B-General_Concept
sorting	I-General_Concept
machines	O
.	O
</s>
<s>
The	O
sorting	B-Algorithm
machine	O
then	O
discards	O
any	O
unnecessary	O
elements	O
.	O
</s>
