EPD E-Paper Modules for Smart Retail: Custom 2.13-Inch and 2.9-Inch Electronic Shelf Labels
2026-11-02
Project Background
A smart retail solution provider in Europe was building an electronic shelf label (ESL) system for supermarket chains and needed a stable e-paper module supply for a rollout across several hundred stores. Their previous supplier delivered acceptable samples but could not hold tolerances across volume batches, and firmware timing differences between batches caused refreshes to fail in the field.
The customer required a 2.13-inch mono module for standard price tags and a 2.9-inch tri-colour module for promotional labels, both with a fixed FPC pin-out that had to match an existing PCB already in production.
What the Customer Needed
- Two e-paper sizes (2.13" mono, 2.9" tri-colour) with the same FPC definition across both models
- Batch-to-batch consistency of refresh waveform and contrast, so one firmware build works on every unit
- EU RoHS compliance evidence acceptable to European retail buyers
- Monthly volumes that stepped up from the rollout phase to the seasonal peak without changing the waveform set
Our Solution
Yingruida engineering started from the customer's PCB and worked backwards: the FPC pin-out, connector position and glass outline were matched to the existing board, so the customer did not have to redesign hardware. Samples of both sizes were built on our EPD e-paper lines in Bao'an, Shenzhen and shipped for firmware validation within the sample round.
To remove the batch variation that had caused field failures before, every production lot is built with a fixed waveform set and released only after contrast and refresh testing on the same fixture, with the waveform file version tied to the lot number. Because the EPD lines run in the same plant as our TFT and OLED lines, the customer could later add a small TFT status display to the same shelf system without opening a second supplier.
Technical Specification Delivered
| Item | 2.13" Mono | 2.9" Tri-colour |
|---|---|---|
| Display type | EPD e-paper, black / white | EPD e-paper, black / white / red |
| Interface | SPI, 4-wire | SPI, 4-wire |
| FPC | Custom pin-out per customer PCB | Same pin-out family as 2.13" |
| Refresh | Full refresh, partial refresh supported | Full refresh |
| Compliance | EU RoHS (EU) 2015/863 | EU RoHS (EU) 2015/863 |
How the Project Ran
| Stage | Work done | Duration |
|---|---|---|
| Requirement review | PCB, firmware and label housing reviewed with the customer's hardware team | Agreed in the kick-off review |
| Sampling | Both sizes built to the agreed FPC definition, tested on the customer fixture | Built to the customer's validation window |
| Pilot batch | Pilot run with contrast and refresh logged per unit | Sized to the field trial |
| Mass production | Scheduled monthly releases with lot-level waveform control | Ongoing |
Results
- Firmware rework after pilot: none — one waveform build covered all units from the pilot batch
- Field failures traced to module batch variation: none reported during rollout
- Hardware redesign required: none; existing PCB reused as-is
- Second product family (small TFT status display) added to the same supply chain
Why Yingruida
Our EPD e-paper lines sit inside a 6,000 m² plant in Shenzhen that also runs TFT colour, PM OLED and custom segment LCD production on 8 module lines, with 2.4 million pcs of monthly capacity and 380 employees. Manufacturing runs under ISO 9001:2015 and ISO 45001:2018 management systems, and our LCD products are independently verified by SGS against EU RoHS Directive (EU) 2015/863 with the result Pass (Report No. SZXEC25004455501, December 2025). For a retail rollout where a firmware mismatch can stop a store from updating prices, that combination of in-house module assembly and lot-level consistency control is what keeps schedules intact.
