LED
Infrared LED
L9437
LED emitting collimated light for optical encoder
L9437 is an infrared LED developed for optical encoders. By improving the aspherical lens used with the previous type L8506, we have achieved
an even more highly collimated beam of near infrared light. The lead pin of L9437 has no step piece that is usually formed at the lead base brazed
to the package, thus eliminating the restriction in printed circuit board design.
Features
Applications
l
Collimated light beam
l
Uniform light spot
l
Narrow directivity: ±5˚
l
High-speed response: 40 MHz Typ.
l
High reliability
l
Optical encoder
s
Absolute maximum ratings (Ta=25
°C,
unless otherwise noted)
Parameter
Reverse voltage
Forward current
Forward current reduction rate
Pulse forward current
P ulse forw ard current reduction ra te
Power dissipation
Operating temperature
Storage temperature
Symbol
V
R
I
F
-
I
FP
-
P
Topr
Tstg
Condition
Value
5
80
0.67
0.5
4.2
150
-30 to +85
-40 to +100
Unit
V
mA
mA/°C
A
mA/°C
mW
°C
°C
Pulse width=10 µs
Duty ratio=1 %
s
Electrical and optical characteristics (Ta=25
°C)
Parameter
Symbol
Condition
Min.
Typ.
Max.
Unit
Peak emission wavelength
I
F
=30 mA
840
870
900
nm
λp
Spectral half width
I
F
=30 mA
-
45
-
nm
∆λ
1
Optical output *
Pe
I
F
=30 mA
1.25
1.6
-
mW
Forward voltage
V
F
I
F
=30 mA
-
1.5
1.65
V
Reverse current
I
R
V
R
=5 V
-
-
5
µA
Light spot size *
2
Bw
I
F
=30 mA
4.0 *
3
4.3
-
mm
Cut-off frequency *
4
fc
I
F
=30 mA ± 4 mAp-p
25
40
-
MHz
*1: Measured with a photodiode (active area:
φ8
mm) installed 25 mm away from LED stem undersurface.
*2: Full width at half maximum of beam spot measured with an image sensor installed 13 mm away from LED stem undersurface.
*3: Reference value
*4: Frequency at which the optical output drops by -3 dB from that at 100 kHz.
1
HAMAMATSU [ HAMAMATSU CORPORATION ]
