Amazon.com's Kindle eReader uses a technology called electronic ink, or e-ink, in which a user's keyboard and toggle commands trigger electrical charges in the device that rearrange and redistribute colored capsules of special polymer ink between two screens. The display shows the text and images of the e-book page that the user requests. If your Kindle displays black spots that cover the text and images, it may be due to one of several causes.
The Kindle's electronic ink display works by sandwiching the pigmented polymer between two specially designed screens. The top screen is transparent so that it can reflect light back to the viewer; the bottom screen rests on the part of the device that distributes electrical currents to the pigmented ink and arranges it into readable text and images. Unlike traditional computer screens, the Kindle screen doesn't have a back light. Its surface is designed to reflect light and mimic the appearance of a conventional piece of paper as much as possible.
Defective e-Ink Display
Over time, or due to a manufacturer defect, the e-ink display on a Kindle can become defective. This may cause parts of the screen to be positively charged at all times. A positive charge triggers the pigmented polymers to recede and absorb light, appearing dark to the viewer. If the display mechanism is defective so that it no longer responds to user actions, your Kindle may have a permanent dark spot in the unresponsive area.
Performing a Screen Refresh
When your Kindle displays the same image continuously, such as with a screen saver, sometimes part of the image stays on even after you've turned on your Kindle and are looking at a different screen. This is called a ghost image. If you see dark spots on your Kindle screen, it's possible that they are leftover patches from a screen saver. If you have a Kindle 2 or newer device, you can easily get rid of these ghost images by pressing the ALT and G keys together, which refreshes your screen.
While Kindle devices are generally designed to be sturdy, Kindle screens can still become damaged. If you've dropped your Kindle, struck the screen, or pressed down onto it too hard, it may become damaged and show dark spots where the damage occurred. If the screen doesn't respond to a screen refresh and you know that the Kindle screen has suffered any kind of blunt-force trauma or mishandling, it's very possible that your screen is physically damaged.
If your screen started showing the black spots within 30 days of your original product purchase, you can mail it back to Amazon.com for a new replacement. If your screen shows signs of defects and you purchased your Kindle less than a year ago, contact Amazon.com's customer service for Kindle warranty questions. The defect may be covered by the warranty, and Amazon.com may either repair your Kindle or replace it with a new one. Unfortunately, defects due to accidents, misuse or user damage aren't covered by the Amazon Kindle warranty.