Design World

  • Home
  • Technologies
    • 3D CAD
    • Electronics • electrical
    • Fastening & Joining
    • Factory automation
    • Linear Motion
    • Motion Control
    • Test & Measurement
    • Sensors
    • Fluid power
  • Learn
    • Ebooks / Tech Tips
    • Engineering Week
    • Future of Design Engineering
    • MC² Motion Control Classrooms
    • Podcasts
    • Videos
    • Webinars
  • LEAP AWARDS
  • Leadership
    • 2022 Voting
    • 2021 Winners
  • Design Guide Library
  • Resources
    • Subscribe!
    • 3D Cad Models
      • PARTsolutions
      • TraceParts
    • Digital Issues
      • Design World
      • EE World
    • Women in Engineering
  • Supplier Listings

Special adhesives bring clarity to optic applications

By Mary Gannon | September 14, 2017

Share

Fiber optic, opto-electronic and photonic applications must have superior transparency, requiring optically clear epoxies, polysulfides, and silicones that exhibit excellent light transmission.

Contributed by Rohit Ramnath, Senior Product Engineer, Master Bond

Fiber-optics adhesives iStock-182681532

Image: iStock

Optical transmission, the ability for light to be channeled through a material, is particularly important for fiber optic, opto-electronic and photonic applications. As a result, superior transparency is an essential characteristic of an optical adhesive. Optical transmission is measured from 0 to 100% on a wavelength scale of approximately 200 to 3100 nanometers (nm). Another common and interchangeable measurement of wavelength is microns, μm. Ultra violet (UV) light typically falls in the 200-400 nm range. From approximately 400-700 nm (0.4-0.7 microns), there is “visible light.” After that, from about 700 nm to 1 mm, you have “infrared light,” (IR) which can be further broken down into near infrared (0.75-2 μm), middle infrared (2-15 μm), and far infrared 15 μm to 1 mm.

Most optically clear epoxies, polysulfides, and silicones exhibit excellent light transmission across the visible, and near IR ranges, with some specialty systems providing a high transmission in the UV and in the middle IR wavelength ranges.

Optical transmission is required in numerous applications. For example, a manufacturer of IR lasers would inquire about epoxies with a transmission capability in the wavelengths between 800 and 1500 nm range. Other applications include LED lights, display panels, and optical lens coupling, which might need optically clear adhesives, sealants, and encapsulants which transmit in the visible range. There are even rare cases where a manufacturer of night vision goggles may need to block UV light.

Table-1-Master-Bond-optical-adhesives

Table 1: Optical Transmission Test Results

To help engineers meet specific requirements for a wide variety of optical related applications, Master Bond has tested several epoxies through independent laboratories, as well as various research organizations at universities over the years. To measure the optical transmission of an epoxy, a cured film, usually about 0.002 to 0.004 in. (2 to 4 mils) in thickness, is prepared. This specimen would then be put through a UV-Vis and IR spectrophotometers to obtain the transmission curve.

Some of the products that Master Bond sent out for independent testing include EP30, EP30-2LB, MasterSil 151, MB600, and UV15. The results and conclusions are reported in the accompanying table* and graphs below. *Disclaimer: Note that the percentages in the table are estimates based on the chart produced by the spectrometer.

MasterBondOpticalChartsCombined_2

Figure 1. Optical transmission test results for EP30, MasterSil 151, MB600 UV15

The graph in Figure 1 shows the results of EP30-2LB, MasterSil 151 and MB600. EP30-2LB is a two-component room temperature curing, optically clear epoxy. Test results showed that this epoxy transmits well from 450 to 900 nm and above. However, it has the unique capability to block UV light completely from 200 to 400 nm, and is widely used in applications where UV blocking is critical, yet transmission is needed in the visible wavelengths.

MasterSil 151 is noteworthy for its low index of refraction and its ability to transmit light very well from 225-2500 nanometers. It is a silicone compound that combines flexibility, high-temperature resistance, strong electrical insulation, and optical clarity. These properties enable it to be used for coating, sealing, and potting applications involving sensitive optical and opto-electronic type applications.

MasterBondOpticalChartsCombined_1

Figure 2. Optical transmission test results for EP30-2LB, MasterSil 151, MB600, and UV15

MB600 retains its optical clarity after curing and has very special light transmission properties, particularly in the UV range of 200-350 nm. It is a one part, aqueous based sodium silicate system widely used for coating applications requiring excessively high temperature resistance, since it is serviceable up to 1,500°F.

The graph in Figure 2 highlights the results of wavelengths ranging from 400 to 3000 nm for these adhesives: EP30, MasterSil 151, MB600, and UV15. EP30 shows very good optical clarity with superior light transmission when compared to many other epoxies. It is a low viscosity, two-part epoxy, widely used for bonding, coating, sealing and casting applications. UV15 is a UV curable epoxy based system, which provides excellent optical clarity and light transmission properties.

To meet ever increasing industrial demands, Master Bond continues to develop advanced systems with unparalleled optical transmittance.

Master Bond
masterbond.com

You may also like:

  • Master-Bond-epoxy-2
    Advanced epoxy adhesives revolutionize structural bonding

  • Optically Clear, Condensation Curing Silicone
  • electronic-components
    Protect Electronics with Silicones

  • Optically Clear, Low Viscosity, High Strength Two Part Epoxy System
  • B-Stage-Film
    High Temperature Resistant B-Staged Adhesive Film Features Thermal Conductivity and…

  • Optically Clear, Two Component Urethane Modified Epoxy Gel Offers Dimensional…

Filed Under: TECHNOLOGIES + PRODUCTS, Adhesives • epoxies, Design World articles, Fastening + joining • locks • latches • pins
Tagged With: masterbond
 

Tell Us What You Think!

Related Articles Read More >

Leading — and not giving advice
stem education
How to get a free STEM education
Hirschtick on the cloud, CAD, and the future
china-manufacturing-future-image
Is China’s manufacturing future in trouble?

DESIGN GUIDE LIBRARY

“motion

Enews Sign Up

Motion Control Classroom

Design World Digital Edition

cover

Browse the most current issue of Design World and back issues in an easy to use high quality format. Clip, share and download with the leading design engineering magazine today.

EDABoard the Forum for Electronics

Top global problem solving EE forum covering Microcontrollers, DSP, Networking, Analog and Digital Design, RF, Power Electronics, PCB Routing and much more

EDABoard: Forum for electronics

Sponsored Content

  • Industrial disc pack couplings
  • Pushing performance: Adding functionality to terminal blocks
  • Get to Know Würth Industrial Division
  • Renishaw next-generation FORTiS™ enclosed linear encoders offer enhanced metrology and reliability for machine tools
  • WAGO’s smartDESIGNER Online Provides Seamless Progression for Projects
  • Epoxy Certified for UL 1203 Standard

Design World Podcasts

July 26, 2022
Tech Tuesdays: Sorbothane marks 40 years of shock and vibration innovation
See More >
Engineering Exchange

The Engineering Exchange is a global educational networking community for engineers.

Connect, share, and learn today »

Design World
  • Advertising
  • About us
  • Contact
  • Manage your Design World Subscription
  • Subscribe
  • Design World Digital Network
  • Engineering White Papers
  • LEAP AWARDS

Copyright © 2022 WTWH Media LLC. All Rights Reserved. The material on this site may not be reproduced, distributed, transmitted, cached or otherwise used, except with the prior written permission of WTWH Media
Privacy Policy | Advertising | About Us

Search Design World

  • Home
  • Technologies
    • 3D CAD
    • Electronics • electrical
    • Fastening & Joining
    • Factory automation
    • Linear Motion
    • Motion Control
    • Test & Measurement
    • Sensors
    • Fluid power
  • Learn
    • Ebooks / Tech Tips
    • Engineering Week
    • Future of Design Engineering
    • MC² Motion Control Classrooms
    • Podcasts
    • Videos
    • Webinars
  • LEAP AWARDS
  • Leadership
    • 2022 Voting
    • 2021 Winners
  • Design Guide Library
  • Resources
    • Subscribe!
    • 3D Cad Models
      • PARTsolutions
      • TraceParts
    • Digital Issues
      • Design World
      • EE World
    • Women in Engineering
  • Supplier Listings