pctechguide.com

  • Home
  • Guides
  • Tutorials
  • Articles
  • Reviews
  • Glossary
  • Contact

DSTN LCD monitors

A normal passive matrix LCD comprises a number of layers. The first is a sheet of glass coated with metal oxide. The material used is highly transparent material so as not to interfere with the quality of the image’s integrity. This operates as a grid of row and column electrodes which passes the current needed to activate the screen elements. On top of this, a polymer is applied that has a series of parallel grooves running across it to align the liquid crystal molecules in the appropriate direction, and to provide a base on which the molecules are attached. This is known as the alignment layer and is repeated on another glass plate that also carries a number of spacer beads, which maintain a uniform distance between the two sheets of glass when they’re placed together.

DSTN

The edges are then sealed with an epoxy, but with a gap left in one corner. This allows liquid-crystal material to be injected between the sheets (in a vacuum) before the plates are sealed completely. In early models, this process was prone to faults, resulting in stuck or lost pixels where the liquid crystal material had failed to reach all parts of the screen.

Next, polarising layers are applied to the outer-most surfaces of each glass sheet to match the orientation of the alignment layers. With DSTN, or dual scan screens, the orientation of alignment layers varies between 90 degrees and 270 degrees, depending on the total rotation of the liquid crystals between them. A backlight is added, typically in the form of cold-cathode fluorescent tubes mounted along the top and bottom edges of the panel, the light from these being distributed across the panel using a plastic light guide or prism.

The image which appears on the screen is created by this light as it passes through the layers of the panel. With no power applied across the LCD panel, light from the backlight is vertically polarised by the rear filter and refracted by the molecular chains in the liquid crystal so that it emerges from the horizontally polarised filter at the front. Applying a voltage realigns the crystals so that light can’t pass, producing a dark pixel. Colour LCD displays simply use additional red, green and blue coloured filters over three separate LCD elements to create a single multi-coloured pixel.

LCD

However, the LCD response itself is very slow with the passive matrix driving scheme. With rapidly changing screen content such as video or fast mouse movements, smearing often occurs because the display can’t keep up with the changes of content. In addition, passive matrix driving causes ghosting, an effect whereby an area of on pixels causes a shadow on off pixels in the same rows and columns. The problem of ghosting can be reduced considerably by splitting the screen in two and refreshing the halves independently and other improvements are likely to result from several other independent developments coming together to improve passive-matrix screens.

HPD – Hybrid Passive Display

In the late 1990s, several evolutionary developments simultaneously increased dual-scan displays’ speed and contrast. HPD (hybrid passive display) LCDs, codeveloped by Toshiba and Sharp, used a different formulation of the liquid crystal material, to provide an incremental, though significant, improvement in display quality at little increased cost. A lower viscosity liquid crystal means that the material can switch between states more quickly. Combined with an increased number of drive pulses applied to each line of pixels, this improvement allowed an HPD LCD to outperform DSTN and get closer to active matrix LCD performance in a LED vs LCD test. For example, DSTN cells have a response time of 300ms, compared to an HPD cell’s 150ms and a TFT’s 25ms. Contrast is improved from the previous typical 40:1 ratio to closer to 50:1 and crosstalk has also been improved.

Another approach was a technique called multiline addressing, which analysed the incoming video signal and switched the panel as quickly as the specific image allowed. Sharp offered a proprietary version of this technique called Sharp Addressing; Hitachi’s version was called High Performance Addressing (HPA). These newer-generation panels all but eliminated ghosting, and generally delivered video quality and viewing angles that put them at least in the same ballpark as TFT screens, if still not quite in the same league.

  • VA – Vertically Aligned LCD Monitors
  • What in the LCD is IPS!?
  • ThinCRT Flat Panels
  • TFT LCD Monitors
  • LCD Resolutions and Picture Scaling
  • Liquid Crystal Light Polarisation in LCD Monitors
  • Polysilicon Flat Panels
  • Plasma Flat Panels
  • PALCD Flat Panels
  • OLED Flat Panels
  • MVA – Multi-domain Vertical Alignment in LCD Monitors
  • LEP Flat Panels
  • LED Flat Panels
  • LCD – Liquid Crystal Displays
  • IPS – In-Plane Switching LCD Monitors
  • HAD Flat Panels
  • Flat Panel Feature Comparisons
  • FED Flat Panels
  • Digital Flat Panels
  • DSTN LCD monitors
  • Creating Colour in LCD Displays
  • Flat Panel ALiS Technology

Filed Under: Flat Panel Displays Tagged With: how does a dstn work, what does dstn mean, what is a backlight, what is a passive matrix

Latest Articles

Soundcard Optical Connections

For analogue CD audio output Connect an analogue CD audio cable from the Analogue Audio connector on your CD-ROM or DVD-ROM drive to CD_IN connector on the sound card. For digital CD audio output Connect a digital CD audio cable from the Digital Audio connector on your CD-ROM or DVD-ROM drive … [Read More...]

Keeping a Cool Computer–Power and Water Cooling

The inside of your computer can be a vicious place. There are all kind of of components competing for power and resources and without proper cooling they can really heat up the inside of the computer. And, heat is a big enemy of a smooth running computer. Heat can actually cause a computer to become … [Read More...]

Macs Get Viruses Too – So Take Precautions

I recently talked to a colleague in Spain about the cybersecurity landscape over there. He made a good point about the fact that Macs are believed to be a lot more secure than they actually are. A lot of this is due to misinformation that originated in the United States, which led to Mac users in … [Read More...]

Gaming Laptop Security Guide: Protecting Your High-End Hardware Investment in 2025

Since Jacob took over PC Tech Guide, we’ve looked at how tech intersects with personal well-being and digital safety. Gaming laptops are now … [Read More...]

20 Cool Creative Commons Photographs About the Future of AI

AI technology is starting to have a huge impact on our lives. The market value for AI is estimated to have been worth $279.22 billion in 2024 and it … [Read More...]

13 Impressive Stats on the Future of AI

AI technology is starting to become much more important in our everyday lives. Many businesses are using it as well. While he has created a lot of … [Read More...]

Graphic Designers on Reddit Share their Views of AI

There are clearly a lot of positive things about AI. However, it is not a good thing for everyone. One of the things that many people are worried … [Read More...]

Redditors Talk About the Impact of AI on Freelance Writers

AI technology has had a huge impact on our lives. A 2023 survey by Pew Research found that 56% of people use AI at least once a day or once a week. … [Read More...]

11 Most Popular Books on Perl Programming

Perl is not the most popular programming language. It has only one million users, compared to 12 million that use Python. However, it has a lot of … [Read More...]

Guides

  • Computer Communications
  • Mobile Computing
  • PC Components
  • PC Data Storage
  • PC Input-Output
  • PC Multimedia
  • Processors (CPUs)

Recent Posts

Disk Defragmenting with Task Scheduler in Windows XP for Computer Maintenance

Scheduling Disk Defragmentation is a little different, inasmuch as it doesn't appear in the default list of software displayed by the the Scheduled … [Read More...]

Dot Trio Monitors

The vast majority of computer monitors use circular blobs of phosphor and arrange them in triangular … [Read More...]

Audio Sampling and Recording Techniques Explained

When a sound card records analogue audio, it is converting the sound waveform into digital information and then copying this … [Read More...]

[footer_backtotop]

Copyright © 2025 About | Privacy | Contact Information | Wrtie For Us | Disclaimer | Copyright License | Authors