Picarro Cyan Laser Single Longitudinal Mode 488 nm Laser

Picarro Cyan Laser
Single Longitudinal Mode
488 nm Laser
Cutting edge laser technology.
Key Features:
High Reliability
Exceptional stability and
optical performance
Compact size,
70 x 125 x 34 mm
Low power consumption,
< 30 W for laser and controller
The Picarro Cyan Laser is a
compact, highly reliable, CW laser
source operating at a fixed wavelength
of 488.0 nm. The laser produces
a beam of exceptional spectral
purity with very stable beam
characteristics over a wide range of
operating conditions. The Picarro
Cyan Laser is also designed and
manufactured to ensure a high
level of reliability.
The laser comes with a separate
controller circuit and cable. A
heatsink and DC power supply are
available as options. Two standard
versions are offered with constant
nominal output power of 10 mW
and 20 mW.

Single Longitudinal Mode
488 nm Laser
Description
The Picarro Cyan Laser is based on a simple
yet elegant design concept that delivers
exceptional optical performance and high
reliability in a compact laser head. From conception
the laser optical assembly, materials,
manufacturing processes and electronic
controls have been designed for high reliability.
The laser configuration is a directly
doubled external cavity semiconductor laser
(DECSL). Figure 1 shows a simplified block
diagram of the Laser.
The two key elements comprising the laser
are 1) a compact and stable external cavity
laser assembly incorporating a high power,
highly reliable semiconductor gain chip and
2) a reliable and efficient extra-cavity second
harmonic generating (SHG) crystal. These
elements are contained in a hermetically
sealed laser sub-assembly.
Hermetic Laser Head Assembly
EXTERNAL CAVITY LASER
SEMICONDUCTOR GAIN CHIP
SHG CRYSTAL
976 nm LIGHT
488 nm LIGHT
Figure 1
Stable External Cavity Laser
The Picarro Cyan Laser uses a single spatial
mode semiconductor chip to directly generate
976 nm light. This differs from other
solid-state blue lasers that use high power
multi-mode laser diodes to pump a second
medium, such as an Nd:YAG crystal or a vertical
cavity semiconductor chip, which in turn
generates light at 946 nm or 976 nm respectively.
The Picarro laser eliminates this step
entirely by directly generating 976 nm light
from a highly reliable semiconductor gain
chip. The chips used by Picarro were originally
designed and qualified for use in high
reliability applications such as fiber optic
communications networks that require continuous
operation for 20 years or more.
The external cavity laser converts the single
spatial mode output from the gain chip into a
stable single spatial and longitudinal mode
beam at 976 nm. The external cavity is constructed
with no moving parts and a simple
wavelength selection scheme. A thermoelectric
cooler (TEC) is used to maintain the
cavity in an optimum operating condition over
a wide range of ambient conditions. Since
the SHG crystal is not included inside the
laser cavity, the monitors and electronic controls
needed to maintain stable laser operation
are greatly simplified when compared to
intra-cavity doubling schemes used in other
laser designs. Simplified monitoring and
control result in more stable and reliable
operation over time and a wide range of
operating temperatures.
Efficient Second Harmonic
Generating (SHG) Crystal
The excellent optical characteristics and
stable performance of the 976 nm external
cavity laser make it possible to use a highly
efficient SHG material in a simple extra-cavity
frequency doubling scheme. By performing
frequency doubling outside the laser cavity,
the SHG crystal performance can be independently
monitored and controlled resulting
in very stable performance. The use of highly
efficient doubling material in an extra-cavity
geometry also results in much lower optical
flux density in the SHG crystal when compared
to intra-cavity doubling schemes.
Lower optical flux density results in longer
crystal lifetime and greater performance stability.
A separate TEC controls the temperature
of the SHG crystal ensuring stable performance
over time and a wide range of
ambient conditions.

Performance
The unique design features of the Picarro
Cyan Laser result in exceptional optical performance
as well as outstanding reliability.
Figure 2 shows a typical output spectrum
plot from a Picarro laser featuring a narrow
single longitudinal mode and high suppression
of spurious modes. A narrow spectrum
with a very stable center frequency can be
beneficial in spectroscopic applications such
as fluorescence excitation.
INTEGRATED NOISE (20Hz–2MHz, RMS, %)
0.30
0.25
0.20
0.15
0.10
0.05
Spec. limit (0.25%)
0
-10
Power in Band 99.997%
λ 0 = 488.04 nm
0.00
0.0 0.2
0.4 0.6 0.8 1.0
TIME (Hrs)
Figure 3
INTENSITY (dBm)
-20
-30
-40
-50
-60
-70
-80
460 470
480 490 500 510 520
WAVELENGTH (nm)
Other laser characteristics of critical importance
for many laser based instruments and
measurements are beam pointing stability,
output power stability, spatial mode quality
and total power dissipation. The Picarro
Cyan Laser performance specifications for
these parameters and others are detailed in
the Specification section of this brochure.
Figure 2
Laser intensity noise is another characteristic
that can be important in scattering measurements
or printing applications. Figure 3
shows typical integrated RMS intensity noise
performance for the Picarro Cyan Laser.
Reliability
At Picarro we have implemented design for
reliability (DFR) practices in the development
of our product and manufacturing process.
The components and materials used in our
lasers have been selected and rigorously
tested to achieve specific reliability objectives.
DFR tools such as Tolerance Analysis
and Failure Mode Effects Analysis (FMEA)
have been extensively used in the product
design, materials selection, component
specification and process development.
Accelerated life testing, environmental
testing and overstress testing have been
conducted on key components, subassemblies
and the complete laser module. The
combined data and knowledge from this reliability
analysis and testing have been used to
develop appropriate screening, burn-in,
process control and surveillance strategies
to assure a high level of reliable performance
from our lasers. These efforts have resulted
in an estimated mean time to failure (MTTF)
for the Picarro Cyan Laser of greater than
20,000 hours. This level of reliability can significantly
reduce the cost and inconvenience
of repeatedly replacing laser heads and laser
tubes during the lifetime of an instrument.
Other laser designs typically exhibit MTTF
values of only 5,000 to 10,000 hours.

Specifications
Environmental and Absolute
Maximum Ratings
Parameter Min Max Units
Storage Temperature –30 70 ºC
Storage relative humidity * 0 100 %
Ambient Operating Temperature 4 40 ºC
Case Operating Temperature 4 55 ºC
Operating relative humidity * 0 90 %
Non-Operating Altitude 0 70,000 feet
Operating Altitude 0 10,000 feet
+12V Supply pin voltage (+12V rail with respect to GND) -0.3 13 V
-12 V Supply pin voltage (-12V rail with respect to GND) 0.3 -13 V
5 V Supply pin voltage (5V rail with respect to GND) -0.3 5.8 V
Warm Up Time from OFF

System Integration and Thermal Management
THERMAL IMPEDANCE (C/W)
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
HEATSINK PERFORMANCE
20 25 30 35 40 45 50 55
AMBIENT TEMPERATURE (C)
The Picarro Cyan Laser, controller and associated
options are sold for use in OEM equipment.
As such the OEM is responsible for compliance
with all applicable safety regulations.
Thermal management is a key consideration
in the mounting and use of the Picarro Cyan
Laser. The laser is designed to dissipate heat
through its baseplate and it is therefore
essential to mount the laser to a heatsink.
The required thermal impedance to properly
heatsink the laser is given below for a range
of ambient temperatures. A heatsink with
integrated fan is also available as an option
from Picarro. The Picarro heatsink is
designed for use with the Picarro Cyan Laser
in ambient conditions up to 40º C.
For further information or questions about
thermal management and mounting the
Picarro Cyan Laser please contact Picarro
at (408)962-3900 or email info@picarro.com.
Laser Head
17.5
19.0
120
5 7.5
FAN PWR
EMISSION
INDICATOR
BEAM EXIT WINDOW
55 70
6
34
10.3 105.5
125
4.0 Dia. 4 Holes
DB25 (PLUG)
FRONT VIEW
TOP VIEW
REAR VIEW
Laser Controller Board
PLAN VIEW
DC INPUT
LED INDICATORS (OP. HOURS)
FRONT VIEW
COMPONENT BOUNDARY
SIDE VIEW
REAR VIEW
H
G
F
UMBILICAL CABLE, DB-25 RECEPTACLE
SERIAL LINK, DB-9 RECEPTACLE
ANALOG INTERFACE, DB-25 RECEPTACLE
SYMBOL
A
DIMENSION
215.56
A
J (6 HOLES)
B
76.25
C
66.05
D
107.54
E
F
97.82
6.35
B
C
G
23.85
H
43.45
J
M4 X 0.7
D
E
BOTTOM VIEW

Contact Information
Picarro Corporate
Headquarters and Sales Offices
United States
Picarro
480 Oakmead Parkway
Sunnyvale, California
94085
USA
Tele (408) 962-3900
Fax (408) 962-3200
Email info@picarro.com
www.picarro.com
International Distributors
Germany
Japan
SOLITON Laser – und Messtechnik GmbH
Postfach 1325
82198 Gilching, Germany
Headquarters
Quantum Design Japan Inc.
Sanpou Ikebukuro Bldg. Annex
4-32-6 Ikebukuro
Toshima-ku, Tokyo, Japan
171-0014
Osaka Branch
Flex Ohtemae Bldg.
1-3-6 Funakoshi Town
Chuo-ku, Osaka, Japan
540-0036
Tele +49 (0) 8105-7792-0
Fax +49 (0) 8105-7792-77
Email info@soliton-gmbh.de
www.soliton-gmbh.de
Tele 81 (0)3 5954 8570
Fax 81 (0)3 5954 6570
www.qd-japan.com
Tele 81 (0)6 4793 1080
Fax 81 (0)6 4793 1081
United Kingdom
Elliot Scientific Ltd,
3 Allied Business Centre,
Coldharbour Lane,
Harpenden, Hertfordshire, AL5 4UT,
United Kingdom
Tele +44 (0)1582 766300
Fax +44 (0)1582 766340
Email sales@elliotscientific.com
www.elliotscientific.com
Israel
Lahat Technologies Ltd.
Teradion I.Z
M.P. Misgav 20179, Israel
Tele 972 4 999 0151
Fax 972 4 999 0826
Email sales@lahat.co.il
www.lahat.co.il/tech/tec_main.html