Last year Sony became the first projector manufacturer to release affordable, or at least relatively affordable, true 4K projectors into the consumer market. Other “4K” projectors then available at consumer-friendly prices used various forms of pixel-shifting to put at least some of the 4K information present in a UHD source onto the screen.
In projectors from JVC (called eShift, up to and including their 2018 models), and from Epson (called “Enhanced 4K”), the 8 million pixels in a true 4K source are first processed down to 4 million by the projector. The first two million of those pixels are then displayed on screen from the projector’s 2K (1080p) imaging chips. A split second later the second 2 million pixels are shifted diagonally by a fraction of a pixel and displayed. All 4 million pixels are therefore present on the screen but in two separate passes, not simultaneously. Persistence of vision blends them together. JVC uses LCOS (Liquid Crystal on Silicon) imaging chips. Epson uses either a similar Liquid Crystal on Quartz technology or LCD, depending on the model. Both the JVC and Epson projectors use three separate 1080p imagers in their optical path, one each for red, green, and blue.
Some consumer 4K projectors employ Texas Instruments’ DLP imaging technology with a similar pixel-shifting technique. In the best of them, all of the original 8 million pixels are displayed, but again not all at the same time. The prime limitation of these DLP pixel-shifters, however, is currently in their color performance. Typical consumer DLP projectors use a single DLP imaging chip (technically known as a DMD, or Digital Micromirror Device) and a rapidly rotating color wheel. Operating that wheel fast enough to offer the wider color offered by Ultra HD sources is a challenge (Professional DLP projectors, such as those used in many commercial cinemas including your local IMAX, or sometimes in the priciest home theaters, use multiple, true 4K imaging chips without pixel-shifting or a color wheel, but their cost runs into six figures).
The results of all this shifting can be remarkably effective, but the commercial appeal of true native 4K projection at prices most consumers were able and willing to spend remained the golden goose. But last year we reviewed Sony's then new VPL-VW285ES, the first relatively affordable, fully 4K consumer projector in which all of the 4K pixels in each frame are displayed on the screen at the same time. At $5000 it certainly wasn’t cheap, but neither was it competitive in cost with a new car.
For 2019, Sony has further refined the VPL-VW285ES, now called the VPL-VW295ES...
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