New SMD Design Increases Yield and Speeds

OpticBlock in SMD
for High-Volume Manufacture
of Smoke Detector Assemblies
TM
Pictured is an example of an SMD design to support an OEM’s
high-volume manufacture of smoke detector assemblies. Excelitas
has partnered with the pioneers in the smoke detection field for
more than 20 years and is a proven leader in supporting
electro-optical smoke detection.
New SMD Design
Increases Yield and Speeds
Manufacturing Throughput
Excelitas Technologies is pleased to introduce a unique surface-mount design
device (SMD), its OpticBlock, ideally suited to high-volume production of smoke
detector assemblies. Excelitas’ OpticBlock consists of a pre-aligned photodiode
(PD) and Infrared LED (IRED) in a fixed optical and mechanical configuration. As
a single component, the OpticBlock is ready to assemble into a smoke chamber
used for electro-optical smoke detection.
The use of Excelitas’ surface-mount OpticBlock, as compared to the use of a
separately-assembled PD and IRED, simplifies your smoke detector assembly
procedure, reduces the need for individual calibration, and increases the overall
yield. Manufacturing throughput is improved, lowering the overall cost to of
Features and Benefits
• Surface-mount (SMD) device, suited
to high-volume manufacture of
smoke detector assemblies
• Consists of pre-aligned Photodiode
(PD) and Infrared LED (IRED), all
in single-component configuration,
ready to be assembled into a
defined smoke chamber.
• Specs for PD and IRED adjusted
to achieve consistent smoke
scatter signal based on VdS and
UL standards.
• Superior design does not obstruct
air flow to the smoke chamber,
allowing for 360 degree smoke
entry.
• 100% tested in Excelitas production
with respect to “Transfer Function”
bringing these products to market.
• Tape-and-Reel packing format
for automated, SMD-compatible
assembly and solder reflow.
Compared to the classical radial assembly of a single PD and IRED device,
• RoHS-compliant
the design of Excelitas’ OpticBlock does not obstruct air flow to the smoke
chamber, ensuring for 360° smoke entry and sensitivity.
Excelitas has been working with the pioneers in the smoke detection field
Applications
for more than 20 years and is a proven leader in supporting electro-optical
•Electro-optical smoke detection
smoke detection. The large area photodiode, Model VTS1188SH, was one of
the industry’s very first smoke detector PDs. In production since 1990, it is still
regarded as a reliable and high sensitivity component.
www.excelitas.com
OpticBlockTM in SMD
for High-Volume Manufacture of Smoke Detector Assemblies
How Electro-Optical Smoke Detection Works
Smoke detection and fire
prevention technologies save lives.
Every year, Excelitas’ sensor
technology for electro-optical
smoke detection prevents over
70,000 fires.
Research studies show that the
odds of dying in a house fire are
half as great if you have a reliable,
working smoke detector, as those
if you don’t.
Electro-optical smoke detection employs an emitter and a photoelectric sensor,
positioned at a predetermined angle as a light detector. Under dark conditions and
with no smoke particles present, the detector’s signal is very low. If smoke enters the
optical chamber across the path of the emitter’s light beam, some light will be scattered by the smoke particles. When the scattered light is directed at the detector, the
detector exhibits a signal, and triggers an alarm. In most instances, the emitter is an
Infrared LED (IRED), at a wavelength between 850 and 950 nm, and the detector is
typically a silicon photodiode (PD). The emitter and detector components are assembled
into a smoke chamber that allows for airflow but avoids light from entering.
For high-volume production, the goal of the smoke detector assembly’s design is to
achieve, with regulated tolerance, triggering of the alarm at a certain smoke level.
Achieving this goal is often difficult, particularly if individual PD and IRED components
are used, and need to be both optically and electrically put together during the pcb
manufacturing process. Large variations in both optical alignment and electro-optical
properties may result, which in turn, can lead to large numbers of reworks.
Making use of an Excelitas OpticBlock assembly offers a very good solution, both for
generating higher yields and faster manufacturing throughput. Here, the IRED and the
PD are provided as a mechanically and optically stable pair, assembled into surfacemount optics, made of durable plastics. The OpticBlock has a specified “Transfer
Function,” which is the PD output signal under a certain reflection value.
The OpticBlock can be ordered in “tape-and-reel” packing format which allows for
automated, SMD-compatible, RoHS-compliant reflow soldering.
Please contact Excelitas to discuss your specific smoke detection design and production
needs. In most instances, you will likely require customized designs based on customized conditions. Innovative, customized opto-electronic solutions are our specialty and
our Sales and Applications teams are happy to assist you.
About Excelitas Technologies
Excelitas Technologies is a global technology leader focused on delivering
innovative, customized solutions to meet the lighting, detection and
other high-performance technology needs of OEM customers.
From safety and security applications to analytical instrumentation,
clinical diagnostics, medical, industrial, and aerospace and defense
applications, Excelitas Technologies is committed to enabling our
customers’ success in their specialty end-markets. Excelitas Technologies
has approximately 3,000 employees in North America, Europe and Asia,
serving customers across the world.
Excelitas Technologies
22001 Dumberry Road
Vaudreuil-Dorion, Quebec
Canada J7V 8P7
Telephone: (+1) 450.424.3300
Toll Free: (+1) 800.775.6786
Fax: (+1) 450.424.3345
detection.na@excelitas.com
Excelitas Technologies
GmbH & Co. KG
Wenzel-Jaksch-Str. 31
D-65199 Wiesbaden
Germany
Telephone: (+49) 611 492 430
Fax: (+49) 611 492 165
detection.europe@excelitas.com
Excelitas Technologies
47 Ayer Rajah Crescent #06-12
Singapore 139947
Telephone: (+65) 6775-2022
Fax: (+65) 6775-1008
detection.asia@excelitas.com
© 2012 Excelitas Technologies Corp. All rights reserved. The Excelitas logo and design are registered trademarks of Excelitas Technologies Corp.
All other trademarks not owned by Excelitas Technologies or its subsidiaries that are depicted herein are the property of their respective owners.
Excelitas reserves the right to change this document at any time without notice and disclaims liability for editorial, pictorial or typographical errors.
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