Use Case: Interactive Classroom Digital Whiteboard

Project: Extra Large PCAP Touch Panel

Project Briefing: A major OEM manufacturer was looking to develop a flagship PCAP interactive educational aid at an aggressive price point to rapidly increase its market penetration.

Challenges: The project’s overall ambition in terms of producing a best-in-class PCAP XL format screen for the education market was a challenge in itself. The product size (65”) combined with the customer’s strict optical and mechanical quality requirements, support for 40 touch points, powered stylus and gestures; low levels of latency and high responsiveness, restrictions on FPC placement and tail numbers, etc. all posed technical and manufacturing difficulties.

Solution: Our engineering team worked over the course of several months to refine a variety of aspects, everything from their cover lens design to their bonding methodology to their enclosure design and mounting method in order to increase production yield and reduce their integration failure rate. Meanwhile our production engineering team worked to increase our own in-house controls and production fixtures to ensure we could meet the customer’s requirements.

Use Case: Medical device

Project: Capacitive switch with glass cover lens

Project Briefing: A medical device manufacturer wanted to upgrade from membrane switches to an easier to clean and sterilize control panel with high levels of chemical resistance.

Challenges: Medical devices require excellent performance stability and need to be easily readable in high levels of indoor lighting. These devices are often cleaned using a variety of fairly caustic chemicals.

Solution: Dignity designed an optically-bonded glass cover lens and capacitive sensor that would minimize glare and provide additional ruggedization and enhanced brightness. In addition, we worked with their engineering team to optimize the enclosure design to ensure sealability and ease of assembly.

Use Case: Large Kitchen Appliances

Project: Capacitive switch with integrated, modular IC

Project Briefing: A large kitchen appliance manufacturer discussed with us the need to upgrade their current range of kitchen and home appliances in order to keep up with current trends in appliance design transitioning towards touch control for mid and high-end products.

Challenges: The manufacturer did not have a deep electrical engineering team and were unable to handle the programming to support the implementation of touch across multiple product lines. They also wanted to standardize the IC and programming across as much of their line as possible.

Solution: Dignity provided them with a capacitive touch sensor with a modular IC attached directly, while also providing extensive programming and tuning support to allow them to bring the product to market. Due to the patented modular attachment method, the same model of IC can be used across a number of product lines, reducing lead time, inventory and other operational issues.

Use Case: Industrial Embedded Touch

Project: Rugged touch panel with enhanced EMC resistance

Project Briefing: Our customer required a rugged touch panel with exceptional strength, able to operate in a wide temperature range and operate reliably in an environment with heavy amounts of EMI.

Challenges: The touch panel needed to combine an extra thick cover lens with reliable touch performance, while factoring in the need to manage touch sensitivity to cope with EMI issues. Cost constraints were an issue, and most traditional EMC filters were not compatible with their budget.

Solution: Dignity’s engineering team walked through each aspect of the machine stack-up, including the current LCD selection, IC selection, air gap, mounting method, etc. in order to optimize EMC-resistance without requiring expensive EMC filters or meshes.

Use Case: Small Kitchen Appliances

Project: Touch panel with integrated touch controller for high-end food processor

Project Briefing: A European home appliance manufacturer came to us with a mature motor driven product that incorporated mechanical buttons which they were looking to upgrade to a touch screen interface in order to match their competitor’s product upgrades.

Challenges: The product was already tooled and in production, and the company wanted to minimize any new tooling and/or changes to mature electrical components – this meant a very small product envelope for incorporating the touch screen and minimal power consumption to avoid needing to upgrade the product’s power supply or motherboard, while also providing exceptional EMI-resistance as the unit’s wattage and horsepower were very high.

Solution: Dignity’s project team analyzed the provide product files, CAD drawings and the product’s assembly documentation and developed a touch screen display module with an integrated touch controller that would enable easy assembly while fitting within the defined power consumption and control panel envelope. In addition, Dignity provided feedback on the programming of the product UI to optimize their solution for the projected capacitive screen provided.

Through extensive knowledge of the home appliance design and manufacturing process, Dignity was able to provide an optimized touch solution within the touch, cost, size and power constraints of an existing product, significantly upgrading the aesthetic and function of the final product.

Use Case: Industrial Machinery

Project: Membrane Switch Panel w/ Ceramic & Metal Substrate

Project Briefing: An industrial machinery manufacturer required a membrane switch with an exceptionally rugged and heat resistant substrate; polymer films by themselves or backed with hard plastics just couldn’t cut it.

Challenges: The operating environment and the machinery’s own reliability demands were on the extreme end; polymers, glass and hard plastics simply were unable to hold up to the kind of abuse that the control panel would be tested for.

Solution: Dignity’s engineering team provided a combination metal and ceramic substrate membrane switch panel that retained excellent responsiveness and reliability, which the ruggedness of the material meant that it was incredibly resistant to any kind of chemical, temperature or physical abuse.

In order to submit an RMA, contact your local sales representative or distributor, or send an inquiry through our after-sales service page. Have the details of your product available, including order number, product serial numbers and production date, etc. Our team will then contact you to provide the necessary documentation and guidelines for the RMA procedure.

Use Case: Amusement Gaming System

Project: Touch display module w/ anti-vandal and custom LED backlight development

Project Briefing: A manufacturer in the field of electronic gaming was looking to increase the screen size of their touch display for use in a game cabinet.

Challenges: The product was sold for installation in bars and restaurants, so it needed to have excellent display ruggedization to resist damage or vandalism, but the display also needed to have high brightness and contrast for use in low-light conditions. To compound the difficulty, the customer wanted a plug and play solution that would function optimally with their other existing components and systems.

Solution: Dignity developed and performed extensive impact and strength testing on the extra-thick touch panel stack specified for the project; at the same time the sourcing and engineering team worked with an LED supplier to develop a backlight that could satisfy the need for exceptional display brightness and lifespan. The final solution was fully fit to plug into the customer’s product as is, without need to alter assembly procedures or other components.

Touchscreens, being made of glass, are vulnerable to breakage, scratching and other damage. Care should always be taken when handling them to prevent injury to either the item or the person handling it. Here are some general guidelines:

• When handling the panel, gloves are recommended to avoid fingerprints, dirt or particles from adhering to the glass and also to avoid injury to from sharp edges.
• When handling the panel, hold it by the edge of the glass with the film facing upwards in order to avoid the film becoming scratched or dirty.
• When assembling the glass panel, do not use excessive force to bend or twist the panel; this may result in the panel becoming deformed.
• When handling the FPC or COF, excessive pulling force, strain or tension must be avoided in order to prevent damage or product defects.
• The tail should not be creased or bent too sharply during assembly. A minimum bending radius of 3mm is suggested. The touch panel must never be held by the FPC or COF.
• Once removed from the original package, touchscreens should not be stacked. The edges may cause scratching.
• Do not stack heavy objects on the touchscreen.

Touchscreens can be vulnerable to electrostatic discharge, extremes of temperature and humidity as well as rough handling. Care should be taken in selecting the location and conditions of a space to store touch screens:

• Touch panels should be stored under controlled environmental conditions of temperature and humidity as specified by the product specification and kept away from chemicals such as acidic or alkaline products, as the damage occurring from contact could affect touch panel function.
• Touch panels should never be stored in a damp environment where condensation could form.
• Do not store touch panels under conditions of exposure to direct sunlight.
• Touchscreens should be stored in original packaging.

This will depend greatly on the type of touchscreen to be cleaned – resistive touchscreens are very vulnerable to damage from detergents or chemicals, while PCAP touchscreens tend to be much more resistant. Product specification documents will have more detailed instructions, but here are some general guidelines for cleaning projected capacitive touchscreens:

• When cleaning the touch panel, refrain from using any kind of strongly acidic, alkaline or organic chemical solvent.
• In case the panel requires cleaning, the use of neutral detergent or isopropyl alcohol is suggested.
• When cleaning the touch panel, always use a soft cloth to avoid abrasions

This is a tricky one – the answer is it varies widely on customer requirements. One of the first factors is the requirements regarding product performance, certification, etc. If client requirements and end use application needs are clear, a product solution can be designed in 1-2 days. However, if there needs to be extensive consultation about performance needs, enclosure and LCD selection, custom sensor pattern design, etc. then the design phase could last multiple weeks. The second biggest factor is client needs regarding sampling and pilot rounds. While the tooling and sample period can be extremely short (20-30 days), depending on how many rounds of samples or pilot rounds are required, and the testing being conducted, the sample verification period can take several months to nearly a year. This is especially true for medical, industrial and mission critical applications that have more stringent certification and testing requirements.

We offer standard product lines for both our PCAP touch panels and our touch display modules; in order to review our lines of standard products, please check the resource section of the website.

We offer both resistive and projected capacitive technologies, the two most widely used touchscreen technologies in the market, but in general this will depend greatly on the specifics of your application, particularly as it relates to EMI resistance, cost sensitivity, durability, touch performance and other aspects. Resistive technology tends to be used primarily in industrial controls or “mission critical” applications like military and avionics. This is due to its high level of EMI resistance and reliability. It’s also used in some applications like POS units due its ability to register touch from any kind of object, including credit cards, passive styluses, etc. and some handheld electronics, largely due to its low cost. Projected capacitive is the most widely used touch technology today, in large part due to its durability, multitouch and gestural capabilities and its excellent optical quantities. It is less cost effective and EMI resistant than resistive but has been improved considerably in both areas as production volumes and manufacturers ramp-up and make incremental improvements. It’s the clear choice for most applications.

There’s no easy answer, and this is why you should be cautious of the various design guidelines you can get on the internet – there’s simply too many factors, and the technology is changing too quickly for you rely on a static document. The best thing to do is to put together a brief project briefing with some of the following information:

• Product end application
• Drawings or specifications if available
• Desired functionality
• Is this a project from scratch, or does the solution need to be compatible with an existing enclosure, housing, PCB, etc.
• What type of testing requirements or certifications do you need to meet?

After you have a project briefing in hand (or even before – our team can walk you through the process), contact one of our sales engineers to schedule a discussion and walk you through some of the possibilities for upgrading your product’s HMI technology.