Sony PSP 3000 - breakthrough LCD feature

[Npl]

Sony PSP 3000 - breakthrough LCD fail-/feat-ure

Seems like the new PSP has an "intentionally" interlaced LCD Display. It bogs down my little brain thinking what went wrong there.
Only sane explaination I have is that Sony added interlaced TV support and added that at the lowest level, so that even the LCD now runs on halfframes.

Or they really believe this is a feature ppl are looking for, but hey it worked for selling cut-in-half Fullscreen TVs for higher prices.

 

[vazel]

I just hope the PSP-2000s are still available for purchase when I get a PSP in January.

 

[Arwin]

It seems to be happening on new iPhone 3G's as well. Maybe it's a new form of power saving or whatever. Will be interesting to hear about it. Someone created an interesting test image:

http://img510.imageshack.us/img510/851/linetestoj5.jpg - it would flicker on PSP-3000 models, but not on older models apparently.

 

[Thowllly]

It seems to be happening on new iPhone 3G's as well. Maybe it's a new form of power saving or whatever. Will be interesting to hear about it. Someone created an interesting test image:

http://img510.imageshack.us/img510/851/linetestoj5.jpg - it would flicker on PSP-3000 models, but not on older models apparently.

I made a new version of the image with italic text for easier reading, higher contrast for more flicker and converted to png for smaller size (44kB -> 1.35kB) http://img186.imageshack.us/my.php?image=displaytestwr1.png

But I'm not sure the image should flicker on an interlaced LCD. On an interlaced CRT it would, sure, because the undrawn lines fade to black while the other lines are being drawn. But on an LCD the undrawn lines should persist from the previous update, so it won't flicker. You'd need an animation to show the effect, a moving image that will show feathering on interlaced displays.

But I could be wrong...

 

[Fafalada]

Seems like the new PSP has an "intentionally" interlaced LCD Display

Well PSP screen always supported interlaced scan as an option(just not a documented one).
When I first heard about this I thought someone might have cocked up the FW to default to interlaced scan(which would be fixable). But yea, if their supposed "hw feature" explanation is true, it sounds an awful lot like what you speculate - the blame most likely being in the new video-controller, and not the screen.
Anyone with the new PSP should try P-Scan TV out and see if that outputs interlaced (that would confirm the controller is faulty at least).

 

[tongue_of_colicab]

Update from Engadget: A Japanese Sony Computer Entertainment representative has informed us that the interlacing-like lines are just "features" of the new LCD, and currently, there are no plans to fix it with a future software update since it is in the hardware.

:')

 

[archie4oz]

The 3000's screen also has a different sub-pixel alignment than the older screens.

2000 screen:
R G B
R G B
R G B

3000 screen:
R R R
G G G
B B B

 

[Arwin]

The 3000's screen also has a different sub-pixel alignment than the older screens.

2000 screen:
R G B
R G B
R G B

3000 screen:
R R R
G G G
B B B

That's interesting ... could it be then we are actually seeing ghosting of the red sub-pixels?

 

[Fafalada]

The 3000's screen also has a different sub-pixel alignment than the older screens.

Well that kinda kills my idea of wasting some money and swapping 3k and 2k screens to see what happens

That's interesting ... could it be then we are actually seeing ghosting of the red sub-pixels?

Doesn't seem very likely given the photos taken show exact odd-even line displacement.

 

[archie4oz]

Sorry, didn't mean to kill your fun...

 

[Shifty Geezer]

What I'm seeing in those comparison pics is the same interlaced rendering, but with no ghosting on the 3000. The lines are present in the 2000 but ghosting blurs it all together. The 3000 image shows only two frames, clearly interleaved with no ghosting to blend it all together. The odd element arrangement might exaggerate the effect further.

The question is, why do these screens use this technique? If the iPhone's also suffer, it has to be a design choice to abandon the effective LCD systems used elsewhere and instead use an alternative that looks stripey. From a design POV it was bound to have issues. With fast refresh and interlaced rendering, you're going to get artefacts. Were they hoping user's persistance-of-vision would hide the stripes?

 

[Fafalada]

With fast refresh and interlaced rendering, you're going to get artefacts.

Just to clarify something - the previous PSPs don't display anything interlaced (since you made the paralel). The reason I'm bringing it up is because interlaced scan was actually possible to enable on early hw (maybe it still is through CFW, but I can't say I've tried), and it looked a fair share different then PSP 1k/2k normally do.

My first theory was the video controller (ie. when they added full support for SDTV-out, they just "unified" everything to interlaced scan). But the iPhones also having this issue, kinda puts that idea at doubt. So, no clue really.
I still hope someone with a 3k can test if TV out on HDTVs is actually progressive (could give some credence to my theory if it isn't).

 

[tongue_of_colicab]

I just read (on a site which link I am not allowed to post here I think) that Sony is about to announce a recall for the psp 3000. One of the sources was from amazon.

 

[Shifty Geezer]

Just to clarify something - the previous PSPs don't display anything interlaced (since you made the paralel). The reason I'm bringing it up is because interlaced scan was actually possible to enable on early hw (maybe it still is through CFW, but I can't say I've tried), and it looked a fair share different then PSP 1k/2k normally do.

What accounts for the visible though subdued interlacing on the PSP2000 screenshot then?

 

[Npl]

What accounts for the visible though subdued interlacing on the PSP2000 screenshot then?

Theres no interlacing on the screenshot, just ghosting. What you probably see is something similar to scanlines, dont know the right word for it, but you see the "gaps" between pixels on a LCD if you zoom in far enough.
Even with a low-response screen like the older PSPs have, interlacing would be very noticeable in motion and different than ghosting.

 

[Brad Grenz]

I just read (on a site which link I am not allowed to post here I think) that Sony is about to announce a recall for the psp 3000. One of the sources was from amazon.

They just canceled the entertainment bundle (with the 4GB Mem Stick). No recall.

 

[Shifty Geezer]

Theres no interlacing on the screenshot, just ghosting...

Oh, yeah. I wasn't looking carefully enough! It's clear that the banding isn't alternating between fields on the PSP2000 image.

On an aside, I think Sony should release a high-end PSP with an OLED screen. I'm sure they could make great money off that!

 

[Fafalada]

On an aside, I think Sony should release a high-end PSP with an OLED screen.

With the whole SKU thing they like so much I always did wonder why they don't do that. The whole premium SKU bs works well for IPods too.

 

[Josh]

There are still some unanswered questions about this:

1) Does the progressive scan TV output display interlaced lines?

2) I've read some reports that the interlacing only occurs on some 2D games and not on 3D games ("mostly"). This is strange to me, so can anyone say anything about this?

3) This is more a question about the human eye, but why do we notice the horizontal black lines caused by the turning off of the same subpixels in a row in a vertical subpixel arrangement (like on the PSP-3000 screen)... more than the vertical black lines caused by the turning off of the same subpixels in a column in a horizontal subpixel arrangement (like on most LCD screens)?

I should really make an illustration about that third question... I'll get one at some unspecified point in the future, heh.

 

[Fafalada]

1) Does the progressive scan TV output display interlaced lines?

Nope.
Some earlier speculations last year were right, it is in fact LCD ghosting, perceived as scanlines because of orientation change in subpixel arrangement. It's also far less noticeable then ghosting on 1k/2k (better response rate and all that).

2) I've read some reports that the interlacing only occurs on some 2D games and not on 3D games ("mostly"). This is strange to me, so can anyone say anything about this?

This is standard LCD behaviour. Response rate varies depending on colors displayed, with some color-transitions much faster then others, resulting in less/more ghosting depending on the content/game displayed.