Electronic Paper Display (EPD): Advantages and Disadvantages

This page explores the pros and cons of Electronic Paper Display (EPD), also known as e-paper display.

What is Electronic Paper Display?

Introduction:

Unlike traditional backlit displays that emit light, e-paper displays reflect light like ordinary paper. This makes them very comfortable to read, with a wide viewing angle. The display mimics the appearance of ink on paper.

• E-paper displays are available in various sizes, such as 1.44”, 1.54”, 1.9”, 2”, 2.13”, 2.6”, 2.71”, 4.2”, 7.4”, 10.2”, and 12.2”.
• They are widely used in applications such as pricing labels in retail stores, timetables at bus stops, smartphone displays, e-book readers, and wristwatches.

Figure 1: 2.7” e-paper display from Pervasive Display Inc. Its dimensions are approximately 264 x 176 pixels, and it’s monochrome. It supports standard serial expansion connectors and can handle UART, SPI, and I2C Input/Output signals.

Figure 2: Back panel of the e-paper display unit.

Popular manufacturers of e-paper displays include E-ink Holdings Inc., LG, NEC, Samsung, Plastic Logic, Polymer Vision, and Seiko Epson.

Benefits or Advantages of Electronic Paper Display

Here are the benefits of using Electronic Paper Displays:

• Low Power Consumption: It holds static text and images indefinitely without using electricity.
• Excellent Contrast: The display contrast is very good and can be viewed from wide angles.
• Natural Reading Experience: It doesn’t have glare and offers a natural reading experience, similar to a book.
• Sunlight Readability: It’s possible to read in direct sunlight as there’s no glare in bright light conditions.
• Long Charge Retention: It holds a charge for a very long time.

Drawbacks or Disadvantages of Electronic Paper Display

Here are the drawbacks of using Electronic Paper Displays:

• Low Refresh Rate: It has a very low refresh rate compared to LCD displays. Therefore, applications requiring fast motion can’t be used.
• Requires External Light: It requires a light source to read, as there’s no backlight like LCDs.
• Static Images Only: It can’t display moving images such as cursors or videos.
• Limited Color Support: It can’t display color e-ink; it can only use shades of gray for display purposes.
• Poor Nighttime Reading: It can’t be used in the dark during bedtime for reading; LCD displays are typically used for that purpose.