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Sharp LCD Display with 1,000,000:1 Contrast Ratio
i4u writes "Sharp announces in Japan that it has developed a LCD display with the world's highest contrast ratio of 1,000,000:1.
The Sharp ASV Premium LCD display panel has a size of 37 inch, 1920x1080 pixel resolution and a brightness of 500cd/m2.
Sharp aims the Mega Contrast LCD display at the professional TV and movie production industry. For comparison the Canon and Toshiba developed SED TV has 100,000:1 contrast ratio."
Doesn't this start to become meaningless at a certain point? I mean, is 1,000,000:1 really any noticeably better than 100,000:1?
Bradley Holt
I wonder if this thing can do black that actually looks black, or if it just gets the high contrast ratio by being able to produce whites brighter than the sun?
Maybe not for the average gaming home application.
...
But in medecine/radiology it can be really useful : makes it easier to spot small subtle differences between to shades of gray on a X-ray pic, when these are located on a larger scale.
i.e.: when an X-ray image has ~1000 shades of gray, and clinically significant information lies in features that are only 2 or 3 levels appart.
You must either use a high contrast display (like this one, or "special for radiology high contrast CRT", or "printed on transparent film and then displayed with ultra-bright backlight")
Or play a lot with contrast & lightning parameters until selected window makes the differences less subtle.
Or even better, use both technique at once.
Also, I'm sure the pr0n industy will find a way to do something useful out of such screens.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
I think the point is that LCDs don't produce a black pixel, because they work by blocking the light from a lamp behind the screen with a thin film of liquid crystal. They always allow some light through, hence the grey appearance of cheap LCDs
It should be duely noted that the projector-LCD system presented in the link has a measured ratio of about 54,000:1 as opposed to the theoretical 200,000:1 ratio. However, I plan to build a $3000 display with a ratio of about 70,000:1. The projector-LCD systems have the advantage of being able to take high precision illumination values. You effectively double the amount of information that can be fed into the display by having two "screens" (the projector and the LCD). Perhaps those who want to experiment with HDR imaging and do not mind a bit of bluring should consider building one of these $1500-$5000 setups, as opposed to those 100,000:1 or 1,000,000:1 displays.
For those who have sunglasses, happy hacking.
*I would have given a HTML link if the Authors' links were functional.
This is not targeted at the home computer user. This is a technology for high-end video gear, and a few years down the road, for high-end home theaters (assuming anything gets released to the public in a yet-to-be-determined HDR video format).
Above the contrast ratio of film or DLP projection, I'll agree it's close to useless, however. Unless some exotic sci/med visualization stuff needs it.
This, of course, is rather silly. We cannot see simultaneous contrast of a billion to one. Our retina is not black, so the light will scatter around in the eye, and give us a flare signal of about a percent or so. We are used to rejecting a low light level like that. That would give us a sensible contrast ratio of 100:1. But this is not the whole story either - if you have a scene on a monitor with only 100:1 contrast, it might look OK in office lighting, but the shadows will look very 'milky' in a darkened room.
In our experience, people using monitors or digital projectors to simulate film will need something like a 1500:1 contrast ratio. There seems to be a point somewhere a bit beneath 2000:1 where the blacks come convincing, and the viewer will accept the simulation. There is some point about 1200:1 where the blacks stop looking convincing, and start looking grey.
If you are trying to match a display to a projector, it is nice to have another factor of two, so you can match the absolute brightness without having to go to the display white. You may want to get this because you sometimes have to drive the RGB channels beyond the white point to get bright and clean looking pastel colours.
You will want to have a continuous tone curve. Field-emission devices will have a cube-type power law down to a point, and then they will cut off exponentially. This may give good-looking greys down to a point, and then plunge into black, crushing all the shadow detail. That does not look as nasty as 'milky' shadows, but it is not that much better.
So - about 3500:1 is good for simulating colour film. However, colour film is pretty dim - 16 ft-lamberts (50 cd/m2) is standard. Images look a lot more colourful if they are brighter. If you want really high-contrast images, you need something like a LCD monitor with a variable LED blacklight, which gives you your local 100:1 contrast and a huge overall contrast ratio. Have a look at http://www.brightsidetech.com/tech/bstech.php.