Does the e-paper screen always flicker when updating the display content?

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The flickering phenomenon observed when an E-paper display updates its content is typically normal behavior and does not indicate screen damage. This is determined by the inherent working principle of E Ink technology.

Why Does E-paper Flicker During Refresh?

Physical Refresh Mechanism:

E-paper relies on charged ink particles (black/white or color) moving under applied voltage to form images.
During each refresh, the screen needs to reset the positions of all particles (resulting in a full-screen flicker between black and white) before rearranging them into the target image. This process causes noticeable visual flickering.

Necessity of Full Refresh:
To prevent ghosting (retention of previous screen content), E-paper requires periodic full refreshes (typically triggered every 5–10 partial refreshes), during which flickering is most pronounced.
Partial refreshes (used for tasks like turning pages in text) produce lighter flickering, but prolonged use without full refresh will degrade display quality.

How to Reduce Flickering?

Adjust Refresh Mode:

• For Dalian Goodisplay’s factory-set monochrome SPI E-paper displays, three modes are usually programmed into OTP (One-Time Programmable memory): "Full Refresh Mode," "Fast Refresh Mode," and "Partial Refresh Mode." Selecting "Fast Refresh Mode" can reduce flickering but may increase ghosting; "Full Refresh Mode" ensures a more thorough refresh but produces more noticeable flickering.
• It is not possible to completely eliminate flickering. Users must make a trade-off between the frequency of flickering and display contrast—achieving faster refresh rates with minimal flickering while maintaining display quality places certain demands on the film (FPL). We always select the most suitable films to produce E-paper displays capable of supporting fast and partial refresh.
  

More User-friendly Design:

• Perform the undesirable full refresh when the user is not actively using the device.
• Enable "Fast Refresh Mode" (automatically reducing refresh frequency) when a static image needs to be maintained for an extended period.
  

Waveform Optimization:

• Optimize refresh strategies through waveform and algorithm improvements.
• Customize waveform files and embed them into OTP according to the varying Vcom values of different batches of E-paper film, allowing users to directly call built-in waveforms and ensuring consistent display performance.
  

Hardware Selection:

• Using E-paper films that support fast refresh (such as E Ink Carta 1200, Kaleido 3) and devices equipped with Regal image waveform technology can significantly reduce flickering.
  

When Might It Indicate a Fault?

• Flickering accompanied by display defects, persistent ghosting that cannot be eliminated, or abnormal local screen content.
• The screen shows flickering stripes or continuous flickering unrelated to the normal refresh process.