In its relatively short life, digital cinema has seen a few picture formats come along: 2K, 4K, 3D, High Frame Rate. Each of these formats is also available in home entertainment, if not identically, then in similar form. The next big thing in home entertainment will be High Dynamic Range (HDR). Is cinema ready?
The HDR in home entertainment will not be the HDR that the camera app on your phone gives you. Nor, in its finest form, is it what Dolby delivers as Dolby Vision in cinemas. Unlike the cinema version of Dolby Vision, the home entertainment version will be more vivid with brighter highlights.
HDR, with or without Dolby, is potent enough that Amazon and Netflix plan to stream content in the format. Hollywood studios are converting libraries. Technology providers are fighting over whose intellectual property will be used to deliver it to the home. It’s no longer a question of if HDR will find its way into the living room, but when. And the answer to that is sooner than one may think. The first HDR television sets will be introduced this year. It will take a few years for this format to take root, but the degree of investment indicates the drive to make it happen. What’s not so clear is how cinemas will respond.
The two important characteristics of good HDR displays are deep black level and high peak luminance. Both characteristics are difficult to provide in a projector. Dolby Vision is the first such technology to come forward in cinema, arguably doing a better job of delivering detail in blacks than in blinding audiences with peak luminance. But that’s largely due to practical limitations. As it is, Dolby’s laser-illuminated HDR projector is estimated to cost in the $1M range. If HDR is to find its way into cinemas in a broad manner, it will have to cost significantly less.
While laser illumination is touted as the savior for cinema, outside of Dolby, it appears that none of the laser projector companies have a road map for HDR-capable projectors. This was confirmed this month at Display Summit, held at Infocomm, with a panel of experts from the three laser projector companies (along with your author). But a tour of the trade show revealed why.
LED direct display walls are coming of age. The finest of the LED direct display walls utilize LED chips mounted on a substrate, with arrays of these mounted on a panel, and only a thin protective coating between your eyes and the chip. The best of these displays deliver stunning contrast, good details in blacks, and have no problem with large color gamuts. Indicting the shift in technology suppliers, the LEDs seen were largely sourced from Chinese foundries, often with administrative, design, and sales offices based in the US. Upon examination of the product catalog from one such foundry, primaries capable of near-Rec 2020 color gamut were evident. Peak luminance levels of 2000 nits (~580 ft-L) for final products were not uncommon. Good black levels are easy to achieve – turn off the LEDs, and there’s no light. Further, large displays have surpassed cinema-level resolution. Two major vendors at the show were boasting pixel pitches of 1.15mm and 1.2mm, respectively. With a 1.2mm pitch, a 5m wide screen (16.5 ft) will deliver 4K.
Equally impressive is the attention to detail in areas such as maintainability and power consumption. Planar, a market leader in LED direct display, not only boasts color-matched panels and precision alignment, but its mounting scheme allows panels tp be replaced in short order thanks to special tools that can be applied at the front of the screen. The tools use magnets to actuate latches inside the panel, allowing the panels themselves to mount next to one another seamlessly. Planar also boasts that a trained technician can replace an LED substrate on the spot with a soldering iron. (Your author did not see this feat performed.)
SiliconCore has patented its power management scheme, producing panels that consume 225 W/m² at 1000 nits (~290 ft-L). The makers of these products spec high light levels for high ambient light conditions. But cinemas, including the HDR variety, operate at much lower light levels on average. LED power consumption linearly tracks lumen output, so one can extrapolate that at 48 nits (14 ft-L), it might be possible to achieve 11 W/m². If so, a 6m wide screen (20 ft) with flat aspect ratio would consume a very cool 220 W. A hand placed on a SiliconCore panel confirms how cool they operate. Of course, more power will likely be consumed with HDR. But even if this calculation is off by an order of magnitude, the power consumption for this quality of display is impressively low.
The question asked by your author while walking the trade show floor was if the cost curve would produce a 6m (20 ft) cinema screen under $100,000 within 5 years. The answer from all but one vendor was an immediate “yes.” 5 years is about the time frame needed for HDR to penetrate home entertainment in a significant manner, raising both consumer expectations and the expectations of content creators. While a 6m screen may seem small (LED direct displays are by no means limited to this size), it fits with the concept of boutique cinemas that are expected to become more commonplace in the future. If HDR catches on with consumers and content creators as expected, it could become the “killer app” for direct LED displays in a new breed of HDR-capable boutique cinemas. Stay tuned.