> For the complete documentation index, see [llms.txt](https://docs.sevenpens.com/drawtab/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.sevenpens.com/drawtab/tech/ips-display-tech.md).

# IPS display tech

## Overview

IPS = "In=Plane Switching"

## IPS panel layers (top-to-bottom)

* glass surface - protects the layers below. The glass may be smooth and glossy or it can be etched so that it provides both anti-glare effects as well as some physical texture or a drawing tablet pen
* Front polarizing filter - polarizes light in the other direction (i.e. horizontally)
* Color filter glass substrate - r,g,b filters aligned to the sub-pixels in the TFT glass substrate. Light going up from here now have color
* Liquid crystal layer - Controls which subpixels can be seen by selectively controlling what light below passes through.
* TFT glass substrate - thin sheet of glass with microscopic circuitry with sub-pixels, light from below passes up through layer.
* Rear polarizing filter - polarizes light in one direction (i.e vertically)
* Diffuser and Prism films
* Light Guide Plate - Evenly distributes the light from the BLU across the entire screen
* Backlight Unit (BLU) - LED lights provide illumination