Wi-Fi-Enabled E-Paper

Pervasive Displays recently released a low-power, Wi-Fi-enabled e-paper display (EPD). The SimpleLink Wi-Fi CC3200 wireless MCU-based EPD is compatible with any of five different EPD panel sizes. You can control it wirelessly over the Internet with the MQTT protocol.pervasive WiFi

The low-power design comprises a SimpleLink Wi-Fi CC3200 LaunchPad development kit featuring n ARM Cortex-M4-based wireless microcontroller. The EPD sits on a BoosterPack-compatible plug-in board, which enables you to choose one of five e-paper display sizes from 1.44″ to 2.7″. An SPI enables communication between the microcontroller and the display.

Operating in the range of 2.3 to 3.6 VDC, the efficient EPD display can be updated via either an attached network or the Internet with a cloud-based application. Application firmware running permits control of the displayed image either via an embedded HTTP page or an MQTT client. With the HTTP client, you can choose from text and image format templates to be displayed and configured according to your needs.

The SimpleLink Wi-Fi CC3200 SDK contains an MQTT example along with the Pervasive Displays driver. The microcontroller uses a FreeRTOS environment with a thread for the SimpleLink functions and a thread for the display communication.

Source: Pervasive Displays


New Tricolor E-Paper Displays

Pervasive Displays recently launched the first two products in its Spectra family of three-pigment black, white and red e-paper displays (EPDs). Intended for a wide variety of applications (e.g., electronic shelf labels and smart cards), the thin Spectra EPD is an active matrix TFT glass substrate display with a 180° viewing angle.Pervasive-Spectra

The 2.87″ E2287ES051 module offers a 296 × 128 resolution and 112 dpi pixel density. The 4.2″ E2417ES053 model has 400 × 300 resolution and 120 dpi high-pixel density. Both anti-glare displays have a vertical pixel arrangement.

Spectra EPD features an SPI interface and a fine-tuned embedded waveform for superior optical performance. You can customize the embedded waveform for your specific applications. The bistable Spectra EPD panels require little power to update; they don’t use power to maintain an image. The displays can operate over an ambient temperature range of 0° to 40°. Breakage detection is supported.

Source: Pervasive Displays

FTDI Arduino-Compatible Touch-Enabled Display Shield Now Shipping

FTDI Chip recently announced the widespread availability of its originally crowdfunded CleO product (and accompanying accessories). FTDI Chip also offers access to software tools, step-by-step tutorials, and projects. FTDI CleOCleO is a simple to program, intelligent TFT display solution that for building human machine interfaces (HMIs) with higher performance than typical Arduino display shields. The initial CleO includes an HVGA resolution, 3.5″ TFT display featuring a resistive touchscreen. An FTDI Chip FT810 high-resolution embedded video engine (EVE) graphic controller executes the HMI operation. An FTDI FT903 microcontroller handles all the additional processing tasks. The advanced display shield provides high-quality graphical animation, even at 60-fps frame rates. In addition, its antialiased graphics capabilities render images in finer detail.

When CleO is combined with FTDI Chip’s NerO—which is an energy-efficient Arduino design capable of operating up to 1 W—it offers a far more powerful solution than a normal Arduino UNO/display shield package.

CleO has an array of useful accessories:

  • AT 57.15 mm × 54.35 mm, the CleO-RIO module provides a mechanism for stacking the CleO shield and an Arduino board together.
  • The CleO-Speaker module (63 mm × 63 mm × 23.8 mm) facilitates the playback music/tones for HMIs where audio functionality has been incorporated. There is also an audio line for input of audio from external sources.
  • The CleO-Camera module has an OV5640 0.25″ 5-megapixel CMOS image sensor plus flash LEDs and a 24-pin 0.5-mm pitch FFC cable.
  • A 9-V power adaptor provides the NerO/CleO solution with up to 1 A of current.

The CleO costs $69. Refer to FTDI’s new forum, www.CleOstuff.com, for design tips, application ideas, and more.

Source: FTDI Chip

Novel Wearable Optical Display

Trulife Optics together with the UK’s National Physics Laboratory has demonstrated a new type of transparent head-up display device.

(Source: TrueLife)

(Source: Truelife Optics)

According to Simon Hall, lead scientist of Adaptive Optics at the NPL the new technology is unlike existing solutions: “Google’s solution is effectively a prism; it’s like a half-silvered mirror that you’re looking into and the Epson Moverio uses an embedded, slightly different refractive index component in a very thick lens which is reflecting light travelling through the rather thick waveguide”.

This new component is set to transform the development of wearable augmented reality and head-up display devices. Jonathan Lewis, CEO at Trulife optics commented that, “The development of wearable augmented reality devices has been curtailed by the lack of an optical component that allows for the overlay of high-definition, full colour images. But with the launch of our optic, we are providing that missing piece in the augmented reality jigsaw.”

Light carrying the image information is transmitted into the first hologram and then turned through 90° through the length of the optical waveguide using total internal reflection before hitting the second hologram. Here it is turned a further 90° then projected into the human eye. This allows for overlaid transparent images to be projected from the centre of the optic in perfect focus. The image is transparent, enabling the overlay of information on whatever subject is being viewed. The optic itself is lightweight, less than 2mm thick, and can be easily mass-produced for consumer and industrial applications.

The device is available now and costs approximately $514 (£300) plus VAT per unit for developers creating prototype devices. The cost of the optic for devices to be made in commercial volumes will depend on the final application and device to be produced.

[via Elektor — Source: Trulife optics]

The Future of Monolithically Integrated LED Arrays

LEDs are ubiquitous in our electronic lives. They are widely used in notification lighting, flash photography, and light bulbs, to name a few. For displays, LEDs have been commercialized as backlights in televisions and projectors. However, their use in image formation has been limited.

A prototype emissive LED display chip is shown. The chip includes an emissive compass pattern ready to embed into new applications.

A prototype emissive LED display chip is shown. The chip includes an emissive compass pattern ready to embed into new applications.

The developing arena of monolithically integrated LED arrays, which involves fabricating millions of LEDs with corresponding transistors on a single chip, provides many new applications not possible with current technologies, as the LEDs can simultaneously act as the backlight and the image source.

The common method of creating images is to first generate light (using LEDs) and then filter that light using a spatial light modulator. The filter could be an LCD, liquid crystal on silicon (LCoS), or a digital micromirror device (DMD) such as a Digital Light Processing (DLP) projector. The filtering processes cause significant loss of light in these systems, despite the brightness available from LEDs. For example, a typical LCD uses only 1% to 5% of the light generated.

Two pieces are essential to a display: a light source and a light controller. In most display technologies, the light source and light control functionalities are served by two separate components (e.g., an LED backlight and an LCD). However, in emissive displays, both functionalities are combined into a single component, enabling light to be directly controlled without the inherent inefficiencies and losses associated with filtering. Because each light-emitting pixel is individually controlled, light can be generated and emitted exactly where and when needed.

Emissive displays have been developed in all sizes. Very-large-format “Times Square” and stadium displays are powered by large arrays of individual conventional LEDs, while new organic LED (OLED) materials are found in televisions, mobile phones, and other micro-size applications. However, there is still a void. Emissive “Times Square” displays cannot be scaled to small sizes and emissive OLEDs do not have the brightness available for outdoor environments and newer envisioned applications. An emissive display with high brightness but in a micro format is required for applications such as embedded cell phone projectors or displays on see-through glasses.

We know that optimization by the entire LED industry has made LEDs the brightest controllable light source available. We also know that a display requires a light source and a method of controlling the light. So, why not make an array of LEDs and control individual LEDs with a matching array of transistors?

The marrying of LED materials (light source) to transistors (light control) has long been researched. There are three approaches to this problem: fabricate the LEDs and transistors separately, then bond them together; fabricate transistors first, then integrate LEDs on top; and fabricate LEDs first, then integrate transistors on top. The first method is not monolithic. Two fabricated chips are electrically and mechanically bonded, limiting integration density and thus final display resolutions. The second method, starting with transistors and then growing LEDs, offers some advantages in monolithic (single-wafer) processing, but growth of high-quality, high-efficiency LEDs on transistors has proven difficult.

My start-up company, Lumiode (www.lumiode.com), is developing the third method, starting with optimized LEDs and then fabricating silicon transistors on top. This leverages existing LED materials for efficient light output. It also requires careful fabrication of the integrated transistor layer as to not damage the underlying LED structures. The core technology uses a laser method to provide extremely local high temperatures to the silicon while preventing thermal damage to the LED. This overcomes typical process incompatibilities, which have previously held back development of monolithically integrated LED arrays. In the end, there is an array of LEDs (light source) and corresponding transistors to control each individual LED (light control), which can reach the brightness and density requirements of future microdisplays.

Regardless of the specific integration method employed, a monolithically integrated LED and transistor structure creates a new range of applications requiring higher efficiency and brightness. The brightness available from integrated LED arrays can enable projection on truly see-through glass, even in outdoor daylight environments. The efficiency of an emissive display enables extended battery lifetimes and device portability. Perhaps we can soon achieve the types of displays dreamed up in movies.