World-first acoustic transparent LED cinema screen debuts

[Brad Miller]

https://www.avinteractive.com/news/d...ts-03-07-2024/

‘Word-first’ acoustic transparent LED cinema screen debuts

By Guy Campos July 3, 2024

The Unilumin UCine LED display in Nanjing, China has a ‘module perforation design’, providing a sound cavity through the cabinet for sound from loudspeakers.

A ‘world-first’ acoustic transparent LED cinema screen has been unveiled at a cinema in China late last month.

Supplied by Unilumin, the screen is said to have “unique” module perforation design, which achieves a sound cavity through the structure of the LED cabinet.

This enables the main sound channel speakers to be placed behind the UCine LED display, which was installed as an upgrade from a traditional IMAX screen at the XinjieKou International Cinema at the Deji Plaza in Nanjing.

The screen is 20.48 metres x 10.8 metres, supports a 4K96 frame rate and has a peak brightness of 300 nits. It also has TÜV low blue light certification, showing a reduction in blue light to protect the eyes.

Unilumin is said to be the first Chinese company to attain Digital Cinema Initiatives (DCI) certification for LED displays. The company is already active in the cinema LED screen market, with installations at the Regency Theater in Los Angeles and the San Ya cinema in Hainan province in China.

The installation in a cinema of acoustic transparent LED follows the launch of the massive, 15,000 sq metre audio-transmissive interior LED display at the Sphere in Las Vegas last year.

Here, Holoplot matrix array loudspeakers concealed behind the screen are able to achieve an evenness of sound level of 98.4 over a distance of 110 metres, thanks to the use of compensation algorithms.

In the case of The Sphere, its audio-transmissive LED puck displays are provided by SACO Technologies.

[Ryan Gallagher]

Was only a matter of time. That is a pretty big screen for only 4K, makes me think the perforation scheme contributed to the reduced pixel pitch.
May not be possible in smaller venues for a while yet, at least at 4K?

[Ryan Gallagher]

Ahh yeah, from their datasheets, it appears the cutoff for the 2K downgrade is anything below a 10M display (I think their units refer to height?)

https://www.unilumin.com/media/uploa...compressed.pdf

2K Series has between a 4 and 2.5mm pixel pitch.

The 4K series is also 4 to 2.5mm (with a 3.33 option in the middle), just requires bigger screens.

Unable to find any pictures of the so called acoustically transparent modules yet.

[Jim Cassedy]

Unable to find any pictures of the so called acoustically transparent modules yet.

I'd be curious to see the specs on power consumption and heat output. I think my
head might actually qualify as "an acoustically transparent module", because my mom
always used to tell me that anything she said went in one ear, and out the other....

[James Gardiner]

Any detail on weight and power consumption compared to a Laser projector.

I hear the current LED screens are so heavy, one of the bigger costs is reinforcement of the building structure to deal with it.

[Mike Blakesley]

While the idea of a super bright screen with great contrast is nice, it then becomes just a huge TV.

I think people are underestimating how much of the magic of movies will be lost without that beam of light going through the air. Maybe I'm just a traditionalist showing his age.

[Steve Guttag]

I was looking for the acoustically transparent specs and couldn't find them. What is the frequency response through the screen? How are things affected if the speaker is rotated some (i.e. Left and Right).

I do think that emissive screens (LED or future technologies) is where we're heading. I'm not very worried about the "magic" associated with projection. I look forward to not seeing seas of red or green from the exit signs, no speckle, no morie, always focused, always converged...and the list goes on. I also would like to have curved screens without the geometric distortions that come from projecting onto curved screens.

[James Gardiner]

I'm with Steve. Any argument that projection is better it like arguing, film is better than digital, or vinyl is better than Cd, is better than streaming. It's not really the point. The GENERAL consumer sees a benefit and that is a commercial advantage for an expanded industry, so that's where the money flows and all we follow as we need money to keep our businesses going.
LED does sound interesting "IF" its price of install and operation/maintenance is comparable to projection. It will easily meet the new 300nit standard SMPTE has been working on.
The new Barco light steering should, in the projector area, also meet the new SMPTE 300nit requirement. All other technologies are, from what I hear, unable to meet that new SMPTE extended Dynamic Range for cinema, needed custom grading passes for each.
Personally, I think its becoming a mess out there in PLF land and the need for a different master for the ever growing better then DCI cinema implementations.

I still am weary on the matching of replaced display cube and meeting the unperceivable difference in colour reproduction. (Ie so you cannot see the colour difference from cube to cube that makes p the screen.)

I hear they have built in colour meters so that can go through a long self calibration mapping out the colour intensity curve over the full range may have fixed this. But imagine the costs of the colour meters needed in every cube.

[Steve Guttag]

I think there is a difference between the analog/digital debate as the medium changes and how it represents the original. There is room for a preference. Projecting a digital image versus displaying a digital image you are getting into do you prefer reflecting light versus emitting light. The pixels are, essentially the same and the storage medium is the same. Perhaps, the color (what wavelength LEDs are available versus laser wavelengths is room for a preference in how the color is generated). There is no magic in the air from the projector to the screen versus the screen to ones eyes. You've introduced an optical element (the lens and probably a port glass), which can only degrade the image.

As for the emissive screen's serviceability, that is going to be a moving target as the technologies evolve. There are already emissive screens where repairs can be done down to the pixel rather than a panel.

As for calibrating/blending new/repaired with existing, we are at the beginning stages of that. I could see a process where, say, when you change a panel, you frame your meter to show 9 panels in a 3x3 grid with the replaced/repaired panel in the middle and then let the screen match/balance the replaced panel with its neighbors. It likely not even need be as expensive as a current spectroradiometer as all the calibration is doing is matching rather than trying to hit a particular standard. You just want the replacement panel to not stand out. One would presume that a screen could run through a set of intensity and color tests rather quickly to plot, for itself a matching curve and be done before the tech has packed up their tools.

And remember this, the technology will never be worse than it is today.

I don't begrudge the early adopters and the path that it takes to get to what will become a standard way of doing things. If the 1999 projectors (the Mark VII series) didn't do their thing with Star Wars Ep:1, we wouldn't have gotten to the "Series 1" projectors which got us to the Series 2 projectors that changed the industry in just 11 years after Star Wars. You have to start somewhere and there were projectors before the Mark VII stuff that were doing screenings.

Emissive screens will happen and I think it is a matter of when the economics of it all make sense.

As for Barco using their light-steering projection for 300nits, I think it is the wrong strategy. There is no evidence that patrons are seeking a 300nit experience from projection cinema anymore than HFR has shown a significant consumer preference. In order to get their light steering projector to hit 300nits, they have to limit their projection size to something like 12m (I forget the exact dimension but it is in that ballpark). That isn't going to fly in PLF screens and this is using their brightest of the bright so it is going to be an expensive projector that can't be used in the bigger auditoriums. Conversely, if they had taken Dolby's approach of 108nits, you have an established level of brightness that has shown strong consumer preference and you can deliver that to PLF rooms. I think a doubling of the light output while simultaneously lowering the black level would have been a more worthwhile venture.

[Ryan Gallagher]

While the idea of a super bright screen with great contrast is nice, it then becomes just a huge TV.

I think people are underestimating how much of the magic of movies will be lost without that beam of light going through the air. Maybe I'm just a traditionalist showing his age.

The magic between the projector and the screen went away about the same time as venues implemented no smoking policies. ;-)
Only the dustiest of old cinemas get anything close to those atmospherics via particulate in the air.

(I joke, but it's also true)

[James Gardiner]

Steve, I can see your point, but this issue is more about industry standards than capabilities.
Yes, doing 108nits is a big jump in quality and is relatively easy to do.
But its not a recognised and documented target that all manufacturer can build to.
The 300nit level was chosen by SMPTE due to extensive testing, It is supposed to be the new DCI spec that every finishing room can calibrate against so any content created in that room can then be played against any vendor projector that has been built to that capability.

So the producers aren't making 6 different masters, exploding the distribution channel and complexity. For example, imagine if we have an Anatar2 type complexity on all films being distributed going forward. Its not a good or cost-effective path.
If anything, you are arguing for SMPTE to make a more parochial EDR spec around 106nits. Your argument is strong, but I don't see any movement on such a path currently.

[Steve Guttag]

James, 108nits is established as every movie mastered for Dolby Cinema (which is pretty much all movies with any sort of budget that would find their way into a PLF theatre) is already mastering to. As such, any projector manufacturer that makes a system that targets 108nits, will further establish that as the theatrical standard for projection. SMPTE standardizes established formats more than creates formats for others to achieve. 108Nits is not so easy to achieve as you make it out. Merely doubling the light output may be "easy" but without a significant reduction in the black levels, you've created a grey rather than a black. Dolby Vision does this and the Barco Light Steering projector can do this and NEC...well...they are struggling to hit 2000:1 sequential (more like 1600:1) as it is on all but the top-end projectors.

I really think 300nits, for today's projection is a foolish target to shoot for and a waste of time/money. It is fine for emissive screens and I think that should be their standard from the get-go, but not projection.

[James Gardiner]

There is a lot more to it than just saying 108nits. The standards go into a lot more detail. Its why all the systems that can do 108nits are all mastered specifically on that custom system.
Their characteristics are different, and no common setup that can be expected to work the same on different system exists.

We are setting ourselves up for master proliferation and excessive costs dealing with it. (Not what we need in this compressed cinema market)

DCI spends a lot of effort to avoid this, so I am uncomfortable with your perspective.

[Steve Guttag]

James, I really don't think so, just as with IAB, we should be able to withstand a universal 108nit standard that other companies are free to adopt (and really, we're talking about 2 other projector companies and one already has one that can probably already work with the vision DCPs or shouldn't be too far away. Whatever is needed on the server side also shouldn't be too far to reach (especially if you want them to go for a 300nit standard.

It is the 300nit standard that will be excessively costly to the industry as it is not achievable except by using the small - medium sized screens but paying beyond the biggest of PLF prices. 108nits is proven, 300nits is not.

Whereas I still see 2K projectors going in and, in the name of "laser" pulling out better xenon projectors (better in the sense of higher contrast, superior lensing/repeatable lens positioning, better color), I don't see all but a fraction of a percent of screens that will want a 300nit projection system. Exhibitors and salespeople are clamoring for the lowest cost not some unproven pie-in-the-sky luminance standard. Save it for emissive screens, where it would make a lot more sense.

[James Gardiner]

My understanding of the different systems, they all have varying capabilities. These capabilities are marketed as being superior to the competitors. You must master in their custom environment to take advantage of these capabilities. It's not within their interest to all pull into a common capacity. It is unlikely to ever happen.
That's why, you typically, as a standards body, set an achievable set of values and then let the vendors create products to these standards. You cannot do it the other way around.

Maybe the stronger of the studios can strong-arm them into accepting a common master, but again, I see comparative incentives making that never happen. I see the vendors of these system offering free remastering services, for now, to keep these perceived marketing differences in play.

But yes, it does sound like a 108nit standard target that DCI gets behind may be a good idea.

This is a bit of a storm in a teacup in any case. a "reset" is underway and many cinemas will be closing as is apparent in the Cineworld announcement. Others will follow.
IMAX and PLF appear ro do better in this lower attendance and streaming world, but PLF offerings will not take a lot of new installs to over subscribe its offerings too. Why we see all these new super expensive projectors in a market that is contracting. It does not really make a lot of sense.. But for the indexing towards PLF offerings, and the vendors desperate to generate turnover in a market where cinemas are holding off projector refreshes as, they don't even know they will be open next year.. let alone 10 years you need to run to get a return on a projector investment.