MobileRead Forums - View Single Post - Project: E-Paper Tablet (touch-typable!)

andrewed · 12-22-2011, 06:31 PM

Firstly, I have grossly erred in claiming that LCD pixels turn on and off with each screen refresh and that eyestrain comes from this.

Thanks to SleepyBob for your diligence with research and HarryT for your initial objection to my claim. As I now understand it:

A liquid crystal cannot turn on and off. It is not a light. It is like a tiny lens that refracts light. It rotates in an electrical field. This changes the amount of light passing through it and produces different colors in the display. Furthermore, a liquid crystal holds its position until instructed to move, regardless of how much the screen refreshes.

I will add a note to the original post so no one else is misled by my error.

And thanks for your patience with my reply. Besides having a hell of a week, SleepyBob's revelation seriously threw me for a loop. I have been very attached to this incorrect idea. When I began reading beyond his references, I got another slight shock:

LED backlighting, which I had assumed would be non-flickering given its DC power source, actually flickers worse than fluorescent backlighting in many screens due to Pulse Width Modulation, used for dimming. See this discussion:
http://forum.tabletpcreview.com/leno...ing-x200t.html

So, in losing one support for my argument, I got another. (Can't say I'm happy about the particular reason, though.) Also, I can now understand the interest in Pixel Qi's reflective displays.

Other responses:

#40 @Kumabjorn
Form factor: I plan on making the device as close to the size of the screen module as possible, with a very narrow bezel. The enclosure would have tiny metal attachment points for cases and accessories. Thus, a case would provide gripping area and possibly a stand. Those who immobilize the device with a rack or stand won't have to work around an unnecessary bezel.
Flip: Yes, screen orientation will be changeable (manually).
USB: Yes, "USB A" in feature list means full size port.

On my approach to design: Frankly, I design for myself. I am the user and customer I keep in mind. Since I design for my needs, the result tends to work for others with the same purpose and sensibility. And I like making refinements and variations based on others' feedback. But I am hopeless at satisfying those who seek titillation from machines.

Maybe see you in January. Safe travels and Happy Holidays!

#41 @Graham
I appreciate your interest and will count your comment as a vote for the 9.7" screen.

However, I do not share your concerns about screen position, size, and speed. I think e-paper's visual neutrality and compactness is going to affect these issues significantly. Such a small, lightweight screen with small type can be held close to the face like a book. There are dozens of new stands for the iPad that position a tablet wherever you want.

Lots of serious writing was accomplished on the 9" Mac Classic. See Specifications post, #21 for more on size.

Regarding refresh rate, check out ihavenotlife's impressive video: http://www.youtube.com/watch?v=Uo6FDJvQ4ek
But again, Kindle 1 refresh rates would suffice for me.

Like I wrote before, my design context for this project is the typewriter. I should have also mentioned pen and paper. I seek a improvement on these using digital elements. The computer doesn't count with me as a writing tool. Yet.

Form factor: Whatever its size, the device will be a slate tablet computer which includes reading software. A stand would be a (detachable) accessory.

#42 @SleepyBob
Thanks again. (See top of this post.)

#43 @HarryT
Thanks again. (See top of this post.)

12-22-2011, 06:31 PM	#44
andrewed typist Posts: 47 Karma: 139812 Join Date: Sep 2010 Location: Helsingborg, Sweden Device: Kindle 3	Responses #4 (Oh boy) Firstly, I have grossly erred in claiming that LCD pixels turn on and off with each screen refresh and that eyestrain comes from this. Thanks to SleepyBob for your diligence with research and HarryT for your initial objection to my claim. As I now understand it: A liquid crystal cannot turn on and off. It is not a light. It is like a tiny lens that refracts light. It rotates in an electrical field. This changes the amount of light passing through it and produces different colors in the display. Furthermore, a liquid crystal holds its position until instructed to move, regardless of how much the screen refreshes. I will add a note to the original post so no one else is misled by my error. And thanks for your patience with my reply. Besides having a hell of a week, SleepyBob's revelation seriously threw me for a loop. I have been very attached to this incorrect idea. When I began reading beyond his references, I got another slight shock: LED backlighting, which I had assumed would be non-flickering given its DC power source, actually flickers worse than fluorescent backlighting in many screens due to Pulse Width Modulation, used for dimming. See this discussion: http://forum.tabletpcreview.com/leno...ing-x200t.html So, in losing one support for my argument, I got another. (Can't say I'm happy about the particular reason, though.) Also, I can now understand the interest in Pixel Qi's reflective displays. Other responses: #40 @Kumabjorn Form factor: I plan on making the device as close to the size of the screen module as possible, with a very narrow bezel. The enclosure would have tiny metal attachment points for cases and accessories. Thus, a case would provide gripping area and possibly a stand. Those who immobilize the device with a rack or stand won't have to work around an unnecessary bezel. Flip: Yes, screen orientation will be changeable (manually). USB: Yes, "USB A" in feature list means full size port. On my approach to design: Frankly, I design for myself. I am the user and customer I keep in mind. Since I design for my needs, the result tends to work for others with the same purpose and sensibility. And I like making refinements and variations based on others' feedback. But I am hopeless at satisfying those who seek titillation from machines. Maybe see you in January. Safe travels and Happy Holidays! #41 @Graham I appreciate your interest and will count your comment as a vote for the 9.7" screen. However, I do not share your concerns about screen position, size, and speed. I think e-paper's visual neutrality and compactness is going to affect these issues significantly. Such a small, lightweight screen with small type can be held close to the face like a book. There are dozens of new stands for the iPad that position a tablet wherever you want. Lots of serious writing was accomplished on the 9" Mac Classic. See Specifications post, #21 for more on size. Regarding refresh rate, check out ihavenotlife's impressive video: http://www.youtube.com/watch?v=Uo6FDJvQ4ek But again, Kindle 1 refresh rates would suffice for me. Like I wrote before, my design context for this project is the typewriter. I should have also mentioned pen and paper. I seek a improvement on these using digital elements. The computer doesn't count with me as a writing tool. Yet. Form factor: Whatever its size, the device will be a slate tablet computer which includes reading software. A stand would be a (detachable) accessory. #42 @SleepyBob Thanks again. (See top of this post.) #43 @HarryT Thanks again. (See top of this post.) Last edited by andrewed; 12-23-2011 at 09:28 PM.