The world’s first flexible, glass-free epd

Discover the first fully-flexible, glass-free, active-matrix
electrophoretic display (EPD) on the market: Lectum®.

A basic display 

Imagine a sandwich without any filler; that’s your basic display. The slice of bread on the bottom is the so-called backplane - usually a matrix of transistors. The slice on top is called the frontplane - the respective display media driven and controlled by the backplane.

The majority of displays currently on the market traditionally use a backplane made of silicon on glass.

If you want to make a flexible display, however, you need to manufacture a flexible sandwich.

Flexible display structure

Making displays flexible

At Plastic Logic Germany, we have successfully industrialized a process, which enables us to create a glass-free backplane. We are the first company worldwide able to manufacture transistor arrays (basically a matrix of transistors) on plastic. 

Instead of using traditional silicon transistors, our active-matrix backplane consists of organic thin film transistors (OTFTs) on PET; that’s exactly the same plastic used to make cola bottles. This means that a flexible backplane can now be coupled with a flexible display medium, such as flexible OLED or flexible EPD, to create a fully flexible display. 

  • Robust and shatterproof
  • Ultra-thin and lightweight
  • Low-power
  • High resolution
  • Extremely legible
  • Production-ready
  • High yield
  • Proven in the market

Lectum®

Lectum uses an electrophoretic plastic frontplane and is the first flexible, glass-free display in volume production.

These high-resolution displays afford the same reading experience as with paper, including an ultra-wide viewing angle. But being completely made of plastic, Lectum displays are much more rugged than standard glass-based EPDs. They are also thinner and lighter per square inch than their conventional EPD counterparts. And because they are EPDs, they are inherently low-power, which is extremely important in today’s increasingly mobile world.

plastic logic display

Lectum plastic displays are available in a wide range of sizes
from very small to the current maximum size of around A4.

Making displays reliable

Once you’ve made your sandwich, you might cover it in plastic wrap before putting it in your lunchbox, bag or satchel in order to protect it from drying out or to avoid the addition of unwanted "ingredients".

The same goes for our plastic display sandwich: we use bottom and top layers of encapsulation to protect the display against humidity and ensure a high level of performance quality and reliability. Nevertheless, we are able to manufacture certain displays with a thickness as low as 475µmm.

Benefits for designers

For the first time in history, product designers can now access a production ready, truly flexible display, which can be integrated in a wide range of accessories in varied markets; from smart cards to wearables and mobile devices to signage.

Designers can choose from a range of display platforms as well as custom display solutions. Independent of the platform, all displays include the following features:

  • organic TFT active matrix, incorporating industry-leading, bi-stable EPD technology
  • COF (chip-on-film) or COP (chip-on-plastic) driver chips
  • can be combined with touch and front light solutions
  • different surface finish options available
  • evaluation kits and reference software available

Benefits for end-users

End users are already benefitting from innovative products integrating Lectum displays; from smartphone accessories providing a second screen platform to smart jewelry, which instantaneously matches your outfit.

Finding the right platform

Plastic Logic Germany has developed three separate display platforms for Lectum displays based on different EPD controllers; all EPD displays require an EPD controller and Lectum displays are no exception.

EPD controllers mainly differ in the maximum number of supported pixels and each of our platforms is, therefore, suited to a specific dimension of display. It should be noted that the number of pixels is not only dependent on the active display area but also on the pixel density (ppi).

We offer reference displays as well as evaluation kits and software for each platform. Please select one from the list below according to your requirements, or select custom design if you are interested in our bespoken display solutions.

Ultrachip
platform

Reference display size:
1.38''

Epson
platform

Reference display size:
4.0'' and 4.9''

Drivers-only
platform

Reference display size:
4.7" and 10.7''

Lectum displays - FAQ


How flexible are Lectum displays?

Unlike conventional glass-based EPDs, Lectum displays are plastic based and therefore the only truly flexible, active-matrix EPDs on the market. They have a typical bendability radius of 50 mm.


Can I fold Lectum displays?

It is possible to bend Plastic Logic displays, but not to fold them. The display bendability radius is typically 50mm, but ultimately depends on the display type and product integration concept.


What is the resolution of Lectum displays?

The resolution of our Lectum displays varies depending on the size. Please refer to the respective datasheet for more details.


How many gray levels do Lectum displays have?

Lectum displays can have up to 16 gray levels. However, this number can vary depending on the display size. Please refer to the respective datasheet for more details.


Are Lectum displays available in color?

Lectum EPDs are not currently available in color. In the past, the company has demonstrated the ability to produce color displays, however, this process has not yet been industrialized for mass production.


What is the refresh rate for Lectum displays?

The refresh rate refers to how quickly a new image can be updated on the screen. Due to the nature of the EPD media, this can be marginally slower than for conventional flat panel displays, such as LCDs. Plastic Logic EPDs have a refresh rate <900 ms, whereby a faster refresh rate is possible in the case of a black/white display without gray-scale


Is video possible on Lectum EPDs?

Plastic Logic Germany has demonstrated animation (12 fps) on its EPDs. However, the faster update rate of the electrophoretic display media, which is required, results in a much higher power requirement than usual as well as a decrease in the display lifetime.


How much power do Lectum displays require?

Our Lectum displays are truly bi-stable meaning power is only needed for an update and not to show a static image. The energy required for a typical image update depends on the display size and driver chip setup; starting at just a few mJ per update for smaller displays, allowing battery-less NFC applications. For details please refer to the respective datasheet.


What is the temperature range for Lectum displays?

Depending on the size and configuration, Lectum displays can operate in conditions of 0°C to 40°C or 50°C and can be stored between -25°C and 40°C or 50°C, whereby the image remains unaltered.


Why is the temperature range limited?

The temperature range for Lectum displays is determined by the electrophoretic display media used, which consists of microcapsules filled with a clear fluid. Low temperatures raise the viscosity of this fluid typically resulting in a slower response time for image updates. That is why the manufacturer states operation at a minimum of 0°C.


What if I require a different sized display to those offered on your website?

We also offer tailor-made display solutions in addition to the reference designs listed in our product portfolio. Custom projects are subject to NRE and a minimum order quantity.


What information is required in order to initiate a custom-design?

We require the following information from you in order to begin custom-design activities: display active area; pixel density; bezel size; location of driver electronics; COF/COP; overall module size including tolerances.


How do you decide which platform a custom design will be based on?

An initial analysis of the requested display active area and the pixel density (as well as a few other boundary conditions) informs the decision about the appropriate display platform. This happens as part of a milestone plan, which we have to developed, enabling a step-by-step development approach.


What is electrophoretic technology?

Electrophoretic technology refers to the process whereby thousands of microcapsules, containing (negatively charged) black and (positively charged) white pigments suspended in a clear fluid, are encapsulated in a plastic sheet.

When a charge (positive or negative) is applied, the corresponding particles move to the top of the microcapsule and the surface appears black or white in this specific area. When the charge is removed, the particles stay where they are. This is called bi-stability: where something can rest in either of two states.

In the case of an EPD, the text and/or images remain on the screen until the next update and the user can continue to view the content without the need for battery power. This means EPDs are inherently low-power and is one of the main differentiators to conventional backlit flat panel displays, where a constant power supply is required to maintain content.


What is a bi-stable display?

A bi-stable display makes use of a bi-stable technology, in this case electrophoresis. The image on a bi-stable display is retained and can be read without a power supply, meaning that any device using such a display is generally deemed to be “low-power”. For example, an eReader only uses battery power when the user turns a page and not when the content is static and being read, which is why many of these devices can claim to have a battery life of up to several weeks between charges. (N.b. eReaders do also require battery power for connectivity, touch, standby and any front light.)