What are Light Guides and What Do They Do For Me?

A Light Guide is a device that allows light to travel from a source as large as the sun or as small as an LED, to a point at some predetermined distance. In a successful light guide application, this is accomplished with minimal losses.

What are the Most Efficient Light Guide applications?

The most efficient Light Guide applications are those that have a controllable source and use optical grade acrylics such as acrylic resin, polycarbonates, epoxies and glass. Controllable sources that are most often used in Light Guide applications are LEDs. Led and Light Guides create effective transmission of light from a PCB to a controller or dashboard as well as a number of additional applications. Efficient light guide systems will also provide the following design elements:

• Effective Coupling  – Without effective coupling from the source to the Light Guide, your system will be inefficient. Typical light guide applications will include a flux coupling to an LED device. The light guide entrance must be either flat (for surface mounted LEDs) or concave and contoured to match the mounting surface.
• Special lenses for Light guides can be manufactured to suit various types of LEDs.  Typically, surface mounted LEDs will have a built-in lens and the prepared end of the Light guide is inserted inside the mount to make the connection.
• Efficient Transmission – Efficient transmission is dependent on a variety of aspects including the Light Guide material, polished connection surfaces, and effective capture at the receiving end.
• Moisture Sealed – Many outdoor or hazardous applications will require moisture and dust sealant to provide an effective transfer of light through your chosen light guide.
• No conduction or transfer of electrostatic discharge (ESD) pulses – LED circuits, especially when mounted on a PCB, are susceptible to losses and damage from electrostatic discharge (ESD) pulses. An effective light guide removes this risk and also the need for an additional ESD protection circuit.
• Immunity to electromagnetic interference (EMI) – For light guides that are implemented into industrial environments, Electromagnetic Interference (EMI) exists, as there are various devices that are emitting electromagnetic waves. An effective Light guide will eliminate this interference.

VCC Optoelectronics provides an extensive variety of light guides called LitePipes, which are patented with the most efficient and technologically advanced design elements. Whether you have an indoor, outdoor, high interference or hazardous application, we have the right light guide for your project. Contact us today for more details and selection assistance from our qualified engineers.

LEDs are increasingly used for display applications. For this purpose, the display should exhibit some favorable characteristics such as strong intensity, bright contrast and uniform illumination.   An LED light pipe, often a plastic-based, injection-molded construct, is an important accessory that plays the role of creating a uniform distribution of LED light flux — incidentally, LEDs create directional light fluxes. For example, in backlighting applications, the directional light from LEDs must be uniformly distributed. This can be done by using LED light pipes. Using light pipes provides two benefits.  First, it keeps the number of LED lights to a minimum and just provides sufficient light to meet brightness requirements.  Secondly, the need for using diffusing elements is minimized if not removed altogether.

LED pipes offer many benefits for private, commercial and industrial use.  The primary benefit is a cost-savings associated with the reduced number of lights — and therefore energy — needed for a particular lighting operation.  LED lights also offer a reduced heat output as compared to other forms of lighting.

How It Works:

The basic optical principle for any LED pipe is quite simple. The geometry of the pipe is important for two needs. First, the LED acts as the source, so the LED-produced light must be coupled efficiently to the LED pipe. The coupled light subsequently floods through the pipe using Total Internal Reflection (TIR). Secondly, the output light must be able to provide uniform illumination via output coupling.  In direct coupling, a slab light pipe, is used.  The LED is a surface mounted diode. The light is propagated throughout the length of the light pipe.  Often, the output couple light passes through layers of diffusing film to further scatter the output luminance distribution and increase uniformity. In indirect coupling, the light from the LED is coupled to the pipe in an intermediate step. In this geometry, a diffuse reflector is used to collect the light from the LED source. The diffuse reflector is used for two reasons:  two colors can be added; and the LED light is already scatted before it enters the pipe, giving more uniformity.

LED Pipe Applications:

LED pipes have many possible applications, ranging from miniature to large-scale. For example, LED pipes can be designed to evenly disperse light over liquid crystal display (LCD) surfaces to render clear images, color or brightness.  One major LED pipe application is to illuminate LCDs for products such as computers, cell phones, signs, and alarm clocks.  LED pipes can be further specialized by creating light pipe systems, which are designed to deliver light to a specific target or output point even if the light’s path is non-linear or obstructed.  Major applications for this type of targeted light delivery are instrumentation, equipment and warning lights, or any system where lighting needs to be routed around existing components.

VCC LED light pipe systems are designed to efficiently transfer light from an LED emitter to a display panel.  VCC light pipes are manufactured from optical grade acrylic, and are available in rigid and flexible components to suit a wide range of instrumentation and applications.

Today’s design considerations call for more and more flexibility in the control systems for automation, production indication, machining, backlighting and more. Often the project is well underway mechanically before full consideration is given to the placement of optical indicators. In other cases, such as new code requirements, a project must be re-worked with existing framework in place. This has led to a rise in the use of light pipes for efficient transfer of data from one point to another.

When using light pipes, the technology implemented to guide light from the source to a lighting task revolves around the efficient application of Total Internal Reflection. Total Internal Reflection, in simple terms, occurs when light transfer is accomplished by reflecting the light off the surfaces of the light pipe. This is a very efficient means of light transfer, however, in

One of the many unique VCC custom light pipes

the real world applications there is more to consider. Surfaces must join, discontinuous paths must be followed and losses can occur.

One of these losses is the return loss or Fresnel reflection loss; more commonly called a Fresnel loss after the French physicist, Augustin-Jean Fresnel. This loss occurs when light crosses the boundary of one medium to another. It will occur at every fiber optic interface due to a change in the refractive index of the materials, which causes some light rays to be reflected back into the source medium.

There are several things that can be done during the light pipe design to control and almost eliminate Fresnel losses. The correct angle of the light rays encountering the material must be considered, using a material such as optical grade acrylic, effective flux coupling and a highly polished tooling process must be utilized to achieve a smooth, scratch-free surface for peak light refraction and optimal light transmission of light from source to target.

VCC Litepipes™ have been designed to provide the ultimate solutions to Fresnel losses. The design provides the best application of Total Internal Reflection by using the best optical grade of acrylic plastic for maximum clarity, implementing a state-of-the-art tooling process and embedding the LED into the light pipe for less coupling loss. We also provide an array of lengths, colors and even custom arrangements for those last minute applications. Contact your dedicated VCC Representative today for more details.

The revolutionary line of Litepipes® from VCC Optoelectronics offers many design advantages that maximize LED light output, increase viewing angles, mix and blend multi-colored LED’s. The LMS and LCS series also provide reliable indication for indoor and outdoor locations that are exposed to dust, water, hose cleaning, rain, sleet and snow. In addition, these light pipes can be implemented in area where they may be exposed to corrosive materials or caustic cleaners. Below is a short breakdown on when to select a VCC Litepipe® from these two lines.

The LMS Series Litepipe®

The LMS Series is designed and exceeded testing criteria for the IP56/NEMA 4C rating. This rating means the incidental contact from dirt, dust or water will not damage this light pipe. It can also withstand cleaners such as those used in food and meat processing environments where disinfectants are used, petro-chemical applications and outdoor environments such as offshore drilling, satellite installations and emergency lighting. High-pressure jets and weather will not degrade the performance of the LMS Series of Litepipes®.

The LCS Series Litepipe®

The LCS Series has been designed to withstand all the criteria of the LMS Series but takes it further and achieves IP67/NEMA6P ratings. This series can be used in both indoor and outdoor applications as well as withstand prolonged immersion in water without compromising the performance of the indicator. This series is perfect for applications such as wastewater treatment plants and any coastal, river, lakeside or pool applications where storm waters may unexpectedly immerse the device location.

VCC takes pride in being an innovator in this field and will continue to develop products such as the LMS and LCS Series of Litepipes for specialized applications. Our team is currently working on a number of new developments and is always available to address your questions. For the advice of a dedicated and knowledgeable VCC professional or to view our complete selection of LEDs, Litepipes, Panel Lenses, Solderless Interconnectors, PCB board Mounts and Clips, contact us today.

High on hills and in mountaintops where reception is the strongest and clearest is where you will find REMEC equipment operating. REMEC provides high-powered, reliable integrated microwave and millimeter wave subsystem solutions for the telecommunications market. Among the products offered by REMEC is an Outdoor Unit to enhance communications and signal processing. The current Outdoor Units offered by REMEC are the only ‘off-the-shelf’ commercial products that are successfully implemented in over 250,000 locations.

Looking to improve the point-to-point and point-to-multi-point signaling for cellular phone call connections to local sites, REMEC designed a power indicator that could be used in conjunction with its line of Outdoor Units.  The visual indicator would have to withstand the kinds of outdoor conditions that can only be delivered by Mother Nature and still equal the reliability of other REMEC products.  After careful deliberation, REMEC selected the VCC LCS series of light pipes to meet this design demand.  The VCC LCS series is a moisturized NEMA certified light pipe that provides a seal against water, dust and ice conditions

About VCC Light Pipes

VCC light pipes are specially formulated UV resistant lens permits the light pipe to provide optimal visual clarity in direct sunlight. The entire line of VCC light pipes increaseefficiency and conserve maintenance time since there’s no physical connection between the PCB board and mounting panel. This permits the PCB to be serviced without requiring a mechanical disconnect.  The 6 different lengths and colors open the field of communication, space and environmental possibilities when designing new, innovative products.

More about the LCS Series Light Pipe

LCS is used for transmitting light from a PCB mounted LED to the front panel while providing protection from the outside environment limiting the chance of water or dust entering the electronic enclosure and not only meeting but surpassing the IP 67/ NEMA 6P requirements. LCS can be used with 5mm, 3mm or surface mount lenses that retain enough clarity to capture outside light and bring it into a photo diode receptor. When light output, clarity, performance and environmental protection are required, the LCS series is a product that should be considered for highly reliable, flexible and successful indication. Contact VCC today and our team will collaborate with you to find the best light pipe solution for your design.

To learn more about REMEC product offerings, click here.

VCC  is a leader in the development of high performance light pipes and we have trademarked our own line (Litepipes™) of innovative options for all your remote signaling and indication needs. To assist in your light pipe selection we’ve provided some factors below help you select the right type of light pipe for your project.

There are many factors to consider when selecting a light pipe to ensure the most effective use in your application. The most important of these considerations are listed below:

• Rigid or Flexible – There are two basic types of light pipes available and those are rigid and flexible. Both have their own strengths as described below:

Rigid light pipes are selected for applications where you have a straight or right angle connection from the power source to the display panel. This lightpipe type is generally                   smaller and less expensive as the wiring cost is minimized by the direct connection.

Flexible light pipes are used when your panel is further away from the power source or when you do not have a straight line of sight connection available. The VCC Flexible                      Litepipe™, one of the most advanced, can provide a 180° viewing angle and very little light degradation even when implemented with extreme bending angles.

• Shape, Size – An extensive selection of light pipe shapes and sizes are available to meet your production and signaling needs. The Litepipe™ series includes but is not limited to square, rectangle and round shapes with sizes ranging from 2.5mm to 5mm. When implementing an intricate signaling process, a combination of different shapes and sizes used in conjunction with different colored LEDs permits a wide range of options for providing clear communication.
• Environment – The environment in which you are placing your light pipe signaling connection is one of the most important considerations to take into account. VCC’s Litepipe™ series has both flexible and rigid options for use in locations that encounter moisture, dust and other debris that can damage and degrade normal connection types. The LMS and LCS series are moisture sealed and have been successfully used in a number of applications with dust and moisture exposure.
• Power – The amount of power available to power your signaling system is often determined by the heat sink abilities of your PCB. VCC’s Litepipe™ series can be implemented with minimum power consumption. There is also a high-intensity Litepipe™ available where a more intense light is required by the design or environment.  One phone call or e-mail to your VCC representative or a look the VCC catalog will provide you with Litepipe™ specifications to find the exact requirements for your selection so it can be built into your power design.

VCC has long been a leader in this field and our experts can provide you with more in depth information regarding our wide array of Litepipes™ and inventive ways to implement them into your design. Contact us today at: www.vcclite.com for all your light pipe needs.

For Scott Health & Safety, when it came to developing an indicator on an instrumental detection device used to identify poisonous gases, the solution presented some special LED requirements. Working in Health and Safety, reliability is essential in every product that is manufactured. To increase the reliability and effectiveness of their product, Scott designed an indicator with increased viewing angles. This was accomplished by splitting the light from a single source LED into a dual output light pipe. The increased viewing angle will provide clear indication for the user no matter how the device is held. Another important feature will be the ability of VCC products to create a tight mounting seal. These combined design requirements are being met through a working partnership between VCC and Scott Safety and Health.

“VCC expertise in quick SLA water clear prototyping and high quality production parts is of great interest to us” said Todd M. Haver. “We are working with VCC because of the experience they have in rapid prototyping and helping guide our engineers in a working design.”

“VCC holds many patents in light management and utilized some of these design characteristics in our custom light pipe application”, said Orlando Diaz Sales Specialist.  “With SLAs we are able to provide a working sample for customers to verify the design”

VCC Experts have the knowledge and skills required to assist you in a variety of applications that present special challenges and circumstances. Our many years of combined experience give us a wide range of applicable solutions from which to draw.  Our large inventory allows us to respond rapidly with samples and product assistance from the prototype stage through production. We also enjoy the challenge of working out custom solutions for new developments. Contact us today with your specialized needs.

Click here for more about Scott Health & Safety Products.

Once again VCC has come through with the high quality products necessary to meet the stringent guidelines of a custom application. One of our prized clients, L3 Unmanned Systems, needed a water tight LED/Lens assembly for use in their flightTEK_® SMC controller.

L-3 Unmanned Systems(L-3 US) provides engineering, designing, manufacturing, integrating and supporting of Unmanned Aircraft Systems (UAS), and has a history of delivering proven products, systems and services for a variety of customers and applications.

To provide a smaller, more integrated flight control system, their specifications required an LED Lens or Litepipe_TM which would provide a moisture-seal, resist shock and vibration, and provide ease of installment for this LED indicator application.

VCC was able to offer a standard, off-the-shelf product to meet their needs. Our LCS 032 CTP, an LED Lens and Litepipe_TM assembly, met all the required specifications. After reviewing and testing the LCS 032 CTP, Michael Stephens from L-3 responded,”We have chosen to design-in your product due to its moisture barrier provided by the o-ring, having no leaks, and very easy to install.”

The LCS series is a threaded, moisture-sealed Litepipe_TM assembly that requires no special tools, just for the retaining ring to be “hand tightened”.  Its CMS 442 lens meets IP67/Nema 6P requirements; providing a seal against water, ice, shock/vibration up to 6g at 2000Hz, Solar & UV exposure.  The attached Litepipe_TM captures the LED light and transmits it up, illuminating the lens thru the front panel. The characteristics of this Litepipe_TM made it the perfect match for this and any application that will be exposed to the elements or requires a protective seal.

This smaller, more itegrated solution developed by L3 Unmanned Systems uses proven, state-of-the-art UAS guidance, navigation and control software and is now available as a stock product.

For more information about L-3US:http://www.l-3com.com/UAS/

Additional information on the new, innovative flight control solution can be found here.