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delphin · 02-21-2011, 07:08 PM

Many of the current readers use 800x600 resolution screens, which along with 1024x768, IS sometimes called SVGA resolution.

I think a little respect and curtasy is in order, because the original poster admitted being confused by all the options.

So here is some general information . . .

FIRST -

We can broadly devide displays into those that are LIGHT EMITTING and those that are non-light-emitting or PASSIVELY REFLECTING.

Examples of LIGHT EMITTING screen technologies include -

- BACKLIT LCD
- PLASMA
- OLED
- CRT

Examples of PASSIVELY REFLECTING screen technologies include -

- REFLECTIVE LCD (both passive and active matrix types)
- E-Ink

Many low cost readers and tablet devices are based on backlit LCD screens that are essentially the same as those used on Laptops, Netbooks, and PC's

Others like the Kindle, and Sony PRS-x50 devices are based on a "paper like" non-light-emitting reflective display called e-ink.

Some, like the Nook, come in BOTH flavors, with models that use Backlit TFT LCD screens AND other models that use passively reflecting 'paper like' E-Ink screens.

In fact at least one company has both a full sized LCD and a full sized E-Ink screen, SIDE BY SIDE ON THE SAME DEVICE.

A few like the Aluratek Libre claim that they are 'epaper' but are really just reflective LCD screens, not the costlier E-Ink technology.

As far as what works best goes . . .

This is all personal preference, and my own personal preferences change depending on what type of material I am reading or viewing.

Reflective screens are still only widely available in BLACK AND WHITE (16 level monochrome) and, despite recent advances, still have limited contrast. Well this is fine for printed text, it does NOT make for good viewing of photographs or complex multi-color illustrations.

So for daily news, magazines, travel guides, etc. I still prefer a nice backlit active matrix TFT LCD screen on a compact Android Tablet or Netbook PC.

For reading novels, short stories, or any mostly straight text based material, I greatly prefer the 'paper like' e-ink screens.

The LCD based reflective screens can routinely achieve contrast ratios that are even better than those available from electrophoretic e-ink devices, so they have some promise, but presently they are not as good as e-ink, because they are not yet well optimized for use in e-book reader devices.

In the LCD market, screens have mostly been optimized for only TWO situations.

1. Small, lower resolution screens for use in ultra long life low power devices like digital watches.

2. Larger, higher resolution TFT active matrix screens optimized for faster updates, used in higher power portable devices like laptops.

If the same ultra low power techniques used in the low power LCD screens used in clocks and digital watches were applied to larger E-Book high resolution screens, then by sacrificing a little on display update speed, you could have an LCD based E-Book reader screen that would compete on battery life with the e-ink screens.

But sadly, no one builds an LCD panel to these specs today, so the devices that do use reflective LCD's, like the Aluratek Libre, have to use a more power hungry TFT LCD technology that limits the battery life to about 24 hours.

So for now, the best two options are black and white reflective e-ink for text, and standard TFT backlit LCD screens for full color images and graphics.

02-21-2011, 07:08 PM	#3
delphin Evangelist Posts: 434 Karma: 346901 Join Date: Dec 2010 Device: SONY PRS-650	Many of the current readers use 800x600 resolution screens, which along with 1024x768, IS sometimes called SVGA resolution. I think a little respect and curtasy is in order, because the original poster admitted being confused by all the options. So here is some general information . . . FIRST - We can broadly devide displays into those that are LIGHT EMITTING and those that are non-light-emitting or PASSIVELY REFLECTING. Examples of LIGHT EMITTING screen technologies include - - BACKLIT LCD - PLASMA - OLED - CRT Examples of PASSIVELY REFLECTING screen technologies include - - REFLECTIVE LCD (both passive and active matrix types) - E-Ink Many low cost readers and tablet devices are based on backlit LCD screens that are essentially the same as those used on Laptops, Netbooks, and PC's Others like the Kindle, and Sony PRS-x50 devices are based on a "paper like" non-light-emitting reflective display called e-ink. Some, like the Nook, come in BOTH flavors, with models that use Backlit TFT LCD screens AND other models that use passively reflecting 'paper like' E-Ink screens. In fact at least one company has both a full sized LCD and a full sized E-Ink screen, SIDE BY SIDE ON THE SAME DEVICE. A few like the Aluratek Libre claim that they are 'epaper' but are really just reflective LCD screens, not the costlier E-Ink technology. As far as what works best goes . . . This is all personal preference, and my own personal preferences change depending on what type of material I am reading or viewing. Reflective screens are still only widely available in BLACK AND WHITE (16 level monochrome) and, despite recent advances, still have limited contrast. Well this is fine for printed text, it does NOT make for good viewing of photographs or complex multi-color illustrations. So for daily news, magazines, travel guides, etc. I still prefer a nice backlit active matrix TFT LCD screen on a compact Android Tablet or Netbook PC. For reading novels, short stories, or any mostly straight text based material, I greatly prefer the 'paper like' e-ink screens. The LCD based reflective screens can routinely achieve contrast ratios that are even better than those available from electrophoretic e-ink devices, so they have some promise, but presently they are not as good as e-ink, because they are not yet well optimized for use in e-book reader devices. In the LCD market, screens have mostly been optimized for only TWO situations. 1. Small, lower resolution screens for use in ultra long life low power devices like digital watches. 2. Larger, higher resolution TFT active matrix screens optimized for faster updates, used in higher power portable devices like laptops. If the same ultra low power techniques used in the low power LCD screens used in clocks and digital watches were applied to larger E-Book high resolution screens, then by sacrificing a little on display update speed, you could have an LCD based E-Book reader screen that would compete on battery life with the e-ink screens. But sadly, no one builds an LCD panel to these specs today, so the devices that do use reflective LCD's, like the Aluratek Libre, have to use a more power hungry TFT LCD technology that limits the battery life to about 24 hours. So for now, the best two options are black and white reflective e-ink for text, and standard TFT backlit LCD screens for full color images and graphics. Last edited by delphin; 02-21-2011 at 07:59 PM.