Optical teardown of a Kindle Paperwhite display by OCT

TL;DR

This paper presents an optical teardown of a Kindle Paperwhite display using OCT, revealing detailed layer structures and particle motion during display state changes, providing insights into display architecture and operation.

Contribution

It demonstrates the use of OCT for non-invasive, detailed imaging of e-ink display layers and particle dynamics, a novel approach in display analysis.

Findings

Layer structures of the Kindle Paperwhite display were successfully imaged.

Particle motion during display state changes was measured using phase-sensitive OCT.

The study provides new insights into the internal operation of electrophoretic displays.

Abstract

An optical teardown, or reverse engineering, of an Amazon Kindle Paperwhite electrophoretic display was performed by Optical Coherence Tomography at 1060 nm. The display incorporates an optical diffuser, lightguide and scattering layers for white light illumination, capacitive touch sensing, and an electrophoretic display. All these layers can be imaged by OCT as well as the thin film transistor array on the back side for driving the pixels. Phase sensitive OCT is used to measure motion of the pigment particles as the display changes between black and white.