New Bi-Level pdp drive technology

Interesting. I wonder if it is related to the Panasonic Hybrid drive or the Pioneer spatial discharge. If you have any more info please post.

http://panasonic.net/prodisplays/dow...0series_US.pdf

Was reading thru this and saw the bi-level stuff. Too bad they dont give that much info on it

The question is; will consumers benefit from this?

The following patent application makes a VERY STRONG case as the technology behind the bi-level driving

20100060625
LINK - note that USPTO links change often. Also use patent2pdf.org if you want to view the figures

I've thoroughly read and understood it and to me it is nothing spectacular or breakthrough. They have added an extra subfield that has no sustain discharge but only a weak erase discharge that produces luminance of half that of a single sustain discharge.

This will improve low level gradation.

The KURO models did something similar with using only spatial discharge for the first subfield.

What you are describing as full power is actually a single sustain pulse. The brightness is modulated by changing the number of sustain pulses. These sustain pulses are then grouped into subfields. For examples a PDP with 10 subfields might have the following groupings:

1st Subfield - 1 sustain pulse

2nd Subfield - 5 sustain pulses

3rd Subfield - 20 sustain pulses

4th Subfield - 60 sustain pulses
.
.
.
.
10th Subfield - 1000 sustain pulses


The bi-level driving system seems to have added a new subfield that has the brightness of 0.5 sustain pulses (effectively acting as half a sustain pulse). This should only improve low level gradation AFAIK.

It is a good point to discuss. I guess my assumption arises from the way they are producing this 0.5 subfield. If I understand correctly, the 0.5 subfield is fixed in weight because it uses only the erase pulse to emit light. All other subfields that use sustain pulses to emit light can be shifted in weight according to APL or whatever because they use AC sustain cycles. I figured this was the reason why they claim "in dark areas".

http://www.panasonic.com/business/pr...5VX300leaf.pdf

I may be misinterpreting. Let me know how you interpret it.

Cheers

Very interesting.

It seems to me they may have used "narrow width pulse" to fix the floating blacks issue (In this erasing discharge, the width of the last sustain pulse in the sustain period is set shorter than the width of the other sustain pulses so that the electric potential difference between the electrodes of each display electrode pair caused by the wall charges thereon is alleviated) and introduced the double ramp voltage generating circuits in VX300 aka bi-level drive tech.

IMHO considering that bi-level drive is restricted to cinema/monitor picture modes (aka low panel brightness setting), they can't afford using it at every APL. If adding this subfield means reducing the weight of latter subfields, that would mean having a even dimmer set and afaik cinema/pro/isf/monitor modes are already <100cd/m². Bi-level must be restricted to low APL then.

Btw, at low APL they could try to combine "bi-level drive" and the infamous "high contrast" driving mode (Fbr). That would mean even more tweaking of the weight of the higher subfields.

Lord, my head hurts already.

maybe this is the new driveing sysetm pany wants in the 2012 models..
i wonder if it will make a huge drifrence

According to AVJ (pana exec), this is not the new 2012 driving system. Btw he already said that the new driving scheme would work on every picture mode (panel brightness setting). Let's hope its a new CLEAR-like sequence adapted to work with a new panel tech and selective initialisation. A real black drive on steroïds as opposed to the same old real black drive tweaked to death with multiple APL related dynamic drive sub-modes.

Nope. That quote is describing a part of the REAL BLACK DRIVE system where the end of each sustain period is used to normalize wall charge to a low value and get ready for selective initialization. Paragraph 005 to 009 are essentially the RBD system AFAIK.


That is very good reasoning . It would be most useful at low APL and with a histogram without any high peak brightness. In other words dark detail scenes.

Will this have any sort of affect on phosphor lag?

Nothing of any significance AFAIK

"I've thoroughly read and understood it and to me it is nothing spectacular or breakthrough. They have added an extra subfield that has no sustain discharge but only a weak erase discharge that produces luminance of half that of a single sustain discharge.

This will improve low level gradation.

The KURO models did something similar with using only spatial discharge for the first subfield.[/quote]"

Xrox, improving low level gradation is a spectacular breakthrough

Pioneer essentially produced every single gray level through some form of dithering (spatial or temporal) AFAIK. And the KURO tech managed to reduce the smallest subfield emission to .1 cd/m2 or less by using spatial discharge only. This combination enables a very large number of low APL gray levels while at the same time limiting visible noise. I don't see Panasonics method as a breakthrough and I doubt that the mass consumer will even notice a difference. But I may be wrong.

BTW - this info is from Plasma Panel Development Division, Pioneer Corporation research paper.

01/05/2012
20120001882 (same here)

In a two-phase driving operation that is performed in at least a sub-field having a largest luminance weight, a first ramp waveform that drops from a first potential to a second potential is applied to a plurality of first scan electrodes, a second ramp waveform that drops from a third potential that is higher than the first potential to a fourth potential that is higher than the second potential is applied to a plurality of second scan electrodes in a setup period, and a scan pulse is sequentially applied to the plurality of first scan electrodes, and then a scan pulse is sequentially applied to the plurality of second scan electrodes in a write period. The two-phase driving operation is employed to prevent a discharge failure during a write discharge.

Sounds like they expanded the bi-level drive trick to the 2012 consumer range :
- Cinema mode : +2 subs @ low APL, native number of graduations 6 144 * 4 = the magic advertized 24 576.
- Other picture modes : 0 to 1 additional sf meaning 6 144 to max 12 288 graduations.

This "two-phase driving" is mentioned in multiple patents. Not bi-level driving IMO. The purpose is to prevent misfiring of pixels due to wall charge loss by having two different reset waveforms depending on the temporal position during addressing.

In other words when addressing 1080 rows of pixels one row at a time the bottom rows must wait too long to be addressed and lose wall charge in the process causing misfiring of pixels in that area.

since the VX300 has some of this tech what are the visual differences between the VT30 and the VX300?

If the VT50 is truly capable of 24k gradients the difference should be night and day from the native 8k panels prior.

Xrox is there really any major improvements you're aware of for 2012 in the Panasonic "2500" drive?

Very little info so far so I couldn't say. The information provided on the Viera global site is very underwhelming so far IMO. Same basic PDP design tweaked. I would have liked something more out of the box like:

- conversion phosphors
- auxiliary electrodes
- 2-electrode spatial discharge
- seperate priming cell
- MgO on phosphor
- replacement of MgO

It will be interesting to get more details on the 1.5x brightness increase and the 2500 drive. I suspect the brightness increase is a result of the shortened address time in combination with a larger green subpixel and apeture ratio.

Yep I figured that out but since there is no dedicated "new Pana patents" thread and I don't wanna mess with the zero black research one, I posted this one here.

Thx for the explanation anyway.

Orso, feel free to post any patents or tech developments in that thread. The more the better IMO. Or you can create a PDP research thread or something along those lines.

No lumens per watt improvement?

Did they get rid of top CEL this year?

Xrox, what is the advantage of conversion phosphors?

There are so many things that we don't know about these sets. The CEL info last year was given by D-Nice and wasn't listed in anything from Panasonic. So maybe they didn't get around to switching to something other than magnesium oxide.

If the panels are now brighter, that would be an improvment on Lumens per watt potentially, right?

Higher address speed used for brightness and larger aperture ratio are both considered/included in lm/w improvements AFAIK.

LOL I was thinking more in terms of energy efficiency so ABL may eventually go away

I'm wondering if OLED TV has ABL

I doubt it. Just too beneficial.


Each cell contains multiple phosphors that convert wavelengths. This enables R and G and B cells to all decay in less than 1ms preventing color seperation, cross-talk, and maximizing motion resolution.


Panasonic use of CEL and reasearch into replacements was disclosed in scientific journals mid 2010 IIRC. Fairly good overall summary of Panasonic technology. D-Nice would probably know if MgO CEL is currently in products or something better such as SrO+.


I would think so. Lm/w improvements are usually only from the cell though IIRC (ie - not from improved filter).

That would have been real news ABL is just too beneficial to any display that generates light inside each pixel. Dramatic impact on lifetime and power. Let us just hope that OLED has an adjustable ABL or a very weak one.