<s>
Canon	B-Algorithm
FL	I-Algorithm
refers	O
to	O
a	O
lens	B-Algorithm
mount	I-Algorithm
standard	O
for	O
35mm	O
single-lens	B-Algorithm
reflex	I-Algorithm
cameras	I-Algorithm
from	O
Canon	O
.	O
</s>
<s>
It	O
was	O
introduced	O
in	O
April	O
1964	O
with	O
the	O
Canon	B-Algorithm
FX	I-Algorithm
camera	O
,	O
replacing	O
the	O
previous	O
Canon	B-Algorithm
R	I-Algorithm
lens	I-Algorithm
mount	I-Algorithm
.	O
</s>
<s>
The	O
FL	O
mount	O
was	O
in	O
turn	O
replaced	O
in	O
1971	O
by	O
the	O
Canon	B-Algorithm
FD	I-Algorithm
lens	I-Algorithm
mount	I-Algorithm
.	O
</s>
<s>
Many	O
mirrorless	B-Device
interchangeable-lens	I-Device
cameras	I-Device
are	O
able	O
to	O
use	O
Canon	B-Algorithm
FL	I-Algorithm
lenses	O
via	O
an	O
adapter	O
.	O
</s>
