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It seems that the VESA shutter glasses syncronisation specification only shows either the left eye image displayed, with logic level 1, or the right eye image displayed, with logic level 0. There seems no method of blanking both eyes, for a short time to reduce ghosting, as required by the Panasonic plama tv's
 

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Quote:
Originally Posted by barrysand /forum/post/18260633


It seems that the VESA shutter glasses syncronisation specification only shows either the left eye image displayed, with logic level 1, or the right eye image displayed, with logic level 0. There seems no method of blanking both eyes, for a short time to reduce ghosting, as required by the Panasonic plama tv's

Makes sense as the VESA standard is old and the Panasonic 3DTV's are brand new based on a new 3D standard.

http://ironicresearch.com/archives/StereoConnector.pdf
 

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Quote:
Originally Posted by Lee Stewart /forum/post/18260736


Makes sense as the VESA standard is old and the Panasonic 3DTV's are brand new based on a new 3D standard.

What "new 3D standard"?


I suspect that you intended to say something like:


"the Panasonic 3DTV's are brand new based on their own propriatory design."



Ultimately (if 3D TV succeeds) we can hope that there are some standards for glasses that enable some degree of interchangability of glasses. But they are not there yet. Meantime, it is a rush to market.
 

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At this point the 3D glasses for the new generation of 3D HDTVs (not computer monitors intended for displaying 3D computer graphics, which the VESA standard was created for) must be considered an accessory specific to the particular brand of 3D HDTV (like a remote control is a brand-specific accessory). While one manufacturer's 3D LCD shutter glasses might happen to work with another manufacturer's 3D HDTV there is no effort being made by the manufacturers to make this happen. However, I suspect that once all of the major manufactures have their 3D HDTVs out in the marketplace, there will be 3rd party vendors making 'universal' LCD shutter glasses that can be configured to work with multiple brands of 3D HDTVs (similar to the available 3rd party universal remote controls).
 

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Not all ASG's are the same as far as their quality. The most important spec is their light transmission % - how much light they block/let into your eyes. The lower the % - the more light they block, the dimmer the images will look.


The differences can be from 15% (blocks 85%) to 40% (blocks 60%)
 

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Quote:
Originally Posted by Lee Stewart /forum/post/18266056


Not all ASG's are the same as far as their quality. The most important spec is their light transmission % - how much light they block/let into your eyes. The lower the % - the more light they block, the dimmer the images will look.


The differences can be from 15% (blocks 85%) to 40% (blocks 60%)

Low transmission is less an issue with LCD displays (where the backlight can overpower the losses of the glasses)than with plasmas.


OTHER characteristics that could be important are:
  • Off state density: How light transmission when the shutter should be blocking.
  • On Delay Time: Time from when ASG is signaled to switch On to when it starts to switch On.
  • Off Delay Time: Time from when ASG is signaled to switc Off to when it starts to switch Off.
  • Rise Time: Time from 10% of max transmission to 90% of max transmission
  • Fall Time: Time from 90% of max transmission to 10% of max transmission
  • Degree of Color Tint: (How much do glasses change the color of the image)


There are likely other important charactersitics too.
 

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Quote:
Originally Posted by davehancock /forum/post/18266456


Low transmission is less an issue with LCD displays (where the backlight can overpower the losses of the glasses)than with plasmas.

If you have to boost the white level to overcome a low transmission % set of ASGs - what is that going to do to the rest of the image?
 

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Quote:
Originally Posted by Lee Stewart /forum/post/18266736


If you have to boost the white level to overcome a low transmission % set of ASGs - what is that going to do to the rest of the image?

A lot less than raising the white level so it goes into clipping (andr reducing Gamma) on a Plasma!
 

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Quote:
Originally Posted by davehancock /forum/post/18267585


A lot less than raising the white level so it goes into clipping (andr reducing Gamma) on a Plasma!

I didn't ask you about a PDP. I asked you about an LCD. That is what you referenced in your post. White level doen't act independently. It also affects black level when raised and LCD's don't have the best black level.
 

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Quote:
Originally Posted by Lee Stewart /forum/post/18267643


I didn't ask you about a PDP. I asked you about an LCD.

I don't care if you asked about PDP or not - the fact remains that LCDs suffer less from low effiency glasses than PDPs.
 

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Quote:
Originally Posted by davehancock /forum/post/18267779


I don't care if you asked about PDP or not - the fact remains that LCDs suffer less from low effiency glasses than PDPs.

Suffer less - how much less? An exact number - no BS adjective.
 

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Quote:
Originally Posted by Lee Stewart /forum/post/18268125


Suffer less - how much less? An exact number - no BS adjective.

An EXACT number would be conjecture at this point. But based on 100IRE of 40ft-l max on a good plasma and 120ft-l on a LED LCD, the rough number would be 300%.


More exact numbers will have to await actual sets that can be measured.


Now this thread is about VESA shutter glasses so I don't intend to go any further into the Plasma vs LCD rathole that you are attempting to go.
 

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Do you guys search each other out? Have you ever met in person? If you could announce a meeting in person, I bet you could sell tickets.
 

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Quote:
Originally Posted by davehancock /forum/post/18266456
  • Off state density: How light transmission when the shutter should be blocking.
  • On Delay Time: Time from when ASG is signaled to switch On to when it starts to switch On.
  • Off Delay Time: Time from when ASG is signaled to switc Off to when it starts to switch Off.
  • Rise Time: Time from 10% of max transmission to 90% of max transmission
  • Fall Time: Time from 90% of max transmission to 10% of max transmission
  • Degree of Color Tint: (How much do glasses change the color of the image)


There are likely other important charactersitics too.

Such as those issues correlated with the raster redraw for the image for each eye. The shutter should be open only after that has been completed, otherwise there will be banding/rolling and other nasty stuff (remember older TV shots of early computer monitors
. It might be that redraw can be completing while the shutter is making its transition to the on state . The goal will be to have the shutter open as long as possible for max light delivery, and some degree of tuning will be needed on the timings for each eye coordinated with the refresh/redraw rate...
 

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Quote:
Originally Posted by AJSJones /forum/post/18282173


Such as those issues correlated with the raster redraw for the image for each eye. The shutter should be open only after that has been completed, otherwise there will be banding/rolling and other nasty stuff (remember older TV shots of early computer monitors
. It might be that redraw can be completing while the shutter is making its transition to the on state . The goal will be to have the shutter open as long as possible for max light delivery, and some degree of tuning will be needed on the timings for each eye coordinated with the refresh/redraw rate...

Raster redraw and such are analog terms - no longer applicable. But your general theme is correct - the timing characteristics of the glasses need to be matched to the display characteristics.
 

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Quote:
Originally Posted by William /forum/post/18283751


If a protector uses LCD shutter glasses would you still need a silver screen?

(I assume that you mean "projector"). Then the answer would be no, if you use LC shutter glasses, you would not need a silver screen.
 

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I don't think the time to create the display is an issue since AFAIK the system is at least double buffering the output so while one image is being displayed another image is being created in a different output buffer, And since the frame rate of the TV 120HZ on plasma and 240Hz on LCD the time to actually change the display is either 1/120th or 1/240th of a second at most.
 

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Quote:
Originally Posted by davehancock /forum/post/18282393


Raster redraw and such are analog terms - no longer applicable. But your general theme is correct - the timing characteristics of the glasses need to be matched to the display characteristics.

Old term maybe, but there is a digital analogy in here somewhere



It was this description that I was referring to - moving the (X-Y raster image) data to the display through the DVI cable bus that appears to take the time . I know it's not an electron beam anymore
but bandwidths and clocks have something to do with getting ~ 6 million dots onto the display every few milliseconds... and needing to make sure the shutters are only open when they should be
. So, yeah, the timing is quite important and may vary from manufacturer to manufacturer.
 
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