1 / 25

Maximizing Hardware & Software Selections for Advanced Touch Screen Applications

Maximizing Hardware & Software Selections for Advanced Touch Screen Applications. Michael Woolstrum CEO , Touch International. We Will Answer. What hardware issues do I need to be aware of prior to designing a touch screen device?

lance
Download Presentation

Maximizing Hardware & Software Selections for Advanced Touch Screen Applications

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Maximizing Hardware & Software Selections for Advanced Touch Screen Applications Michael WoolstrumCEO, Touch International

  2. We Will Answer • What hardware issues do I need to be aware of prior to designing a touch screen device? • How do my hardware choices affect software development and system performance? • Topics Covered: • Touch Product Design Considerations • Touch Technology Issues • Designing for High-Performance • Touch Screen Tail Design • Choosing the Right Interface • Touch Screen Electronics • Tuning, Firmware & Calibration

  3. Design Considerations When designing a unit, consider: • Size of display and overall system size • How you want touch screen to look and function • Application • Time to market • Environment • Industry regulations • Cost

  4. Display Considerations Key LCD Considerations • LCD lifespan is short – 3 years is common • No standard dimensions – 7” is most standard size • Select narrower borders for flush finish • Design bezel and touch screen for LCD changes • Does application require high-bright, high/low temp, high light transmission, or sealable LCD? • Is LCDeasily acquired? • Cost

  5. Touch Technology Determine Touch Technology • Things to consider: • Application • Environment • Availability • Cost • Also consider • Difficulty to manufacture (complexity) • Touch input method (finger, pen, glove) • How long does touch screen need to last?

  6. Touch Technology Issues Projected Capacitive for iPhone Experience • Custom designs often very complex • Higher cost compared to resistive • False touches possible • Tuning required • Prone to noise interference – may require EMI shielding • Multiple input methods dependent upon tuning • Sensitive to water • Integration can be complex

  7. Touch Screen Integration Typical Projected Capacitive Touch Screen Integration Add back housing to graphic

  8. Touch Technology Issues Resistive for Low Cost • Moving parts make resistive not as durable • Cover glass is not typically an option • Requires input pressure • Periodic recalibration • Lower optics • Requires bezel around touch screen • Not the “look” that many expect today

  9. Touch Technology Issues Optical for Large Format • Occlusion (line of sight) problems when light path is blocked • Subject to interference from other light sources or reflections • Thicker bezel needed to hide IR cameras (3mm for 19” screen) • Possibility of false touches • Susceptible to ghosting

  10. Touch Screen Integration

  11. Designing for High-Performance Meeting Industry Regulations with Display Enhancements • Adding display enhancements to touch can correct many environmental and regulatory issues. • Military, Medical, Aerospace Industries – many requirements • Aerospace – HIC Compliant, Self Extinguishing, Low Toxicity • Military - NVIS compliant, EMI shielding, high-temperature tolerant • Medical - NEMA sealable, anti-microbial, shatterproof

  12. Display Enhancements Military Application Requirements • Extreme Outdoor Environments • Advanced Sunlight Readability • Optimized Video & Light Images • NVIS (Night Vision Imaging System) Compliant

  13. Tail Design • Key component to getting touch screen right • Consider how much room tail has and placement of it • Bending tail can damage communication • Chip-on-Flex • Only available for projected capacitive • Allows for tail to be long and far away from electronics • Minimizes noise and interference • Entire sensor scrapped if chip needs to be replaced • Chip-on-flex is expensive

  14. Choosing the Interface Method • I2C • USB • Projected capacitive accepts any interface method • Resistive requires USB or RS232 • Optical usually USB HID • Motherboard input type often plays role in choosing interface method. • Off-the-shelf unit (lowest cost) limits interface flexibility • In-house design (expensive) allows for all options • USB HID • Serial (RS232) • Serial HID • USB-UART

  15. Touch Screen Electronics Touch screen performance controlled by controller • Converts electronic signal sent from touch sensor to the host PC through a I2C, serialor USB interface in an X/Y format. • Two Types • PCB (traditional controller board) • Chip-on-Flex

  16. Touch Screen Electronics PCAP Controller Challenges • False touch • Subject to EMI noise • Cost can be very expensive depending on capabilities • If slim design/space constraints, then chip-on-flex • Custom firmware required for PCAP

  17. Touch Screen Electronics Resistive Controllers • No real challenges with resistive electronics • Traditional resistive controller (4, 5, 8-wire) very low cost • Multi-touch resistive controllers are expensive • Chip-on-flex not an option (also not needed) • Easy to integrate or replace Optical Controllers • Any issues with them?

  18. Firmware/Drivers/Calibration Insert Graphic

  19. Firmware/Drivers/Calibration Firmware • Tells touch screen what kind of touches or input to pay attention to or ignore • Can make touches more or less sensitive (application specific) • Provides system level EMI shielding Drivers • Mainstream OS drivers loaded on chip • Customer must write own drivers for custom OS

  20. Firmware/Drivers/Calibration Drivers • Mainstream OS (Windows 7) drivers loaded on chip • Android, Linux drivers usually available from chip manufacturer • Customer must write own drivers for custom OS Calibration • Projected Capacitive, Optical, MARS - one time calibration • Analog Resistive – periodic calibration

  21. Software Selections for Advanced Touch Screen Applications Jeff Carpenter CEO, Ringtail Design

  22. What We Will Cover • What are the advantages and limitations of software tools used to develop touch applications? • How to choose the best software development method for interactive platforms See word document for software section outline.

  23. Operating Systems Windows 7 • Industry standard touch screen platform • Supports multi-touch • Plug and play – does not require additional drivers Android • Supports native multi-touch • Additional drivers needed to run touch screen

  24. Operating Systems Linux • Supports native multi-touch • Additional drivers needed to run touch screen iOS/Leopard • Supports native multi-touch • Additional drivers needed to run touch screen All operating systems available as embedded O/S

More Related