Is DLP's 4K Really 4K?

Texas Instruments’ new chip has enthusiasts asking that question.

Texas Instruments has upped the DLP game with the recent rollout of their newest digital micro mirror device DMD), claiming full Ultra HD performance. The 0.66-inch chip has nearly the same physical dimensions as the DLP chip found today in many 1080p home theater and business application projectors. It features a native resolution of 2716 x 1528 pixels, which combined with an optical actuator used for pixel shifting, allows for an onscreen image of 8.3 million pixels—roughly the same as a native 3840 x 2160 UHD imaging chip. The chip’s compact size is said to allow for more cost-effective manufacturing—and has resulted in a new $2,000 low price point for at least one Optoma 4K projector.

How’s It Work?

Both TI and manufacturers implementing the chip call the result a true 4K image despite the lower native resolution on the DMD and its inability to deliver all the pixels of an Ultra HD frame at one time. The pixel-shifting approach employed here is similar to the solutions used over the years by JVC and more recently by Epson, both of which involve native 1920 x 1080 (1080p) imaging chips that are then doubled onscreen via an optical actuator to deliver “4K-like” images without the expense of true 4K native imaging chips. Old-timers may recall that the first 1080p DLP devices— notably those used in rear-projection TVs from the likes of Hewlett-Packard and Samsung around 2007—also achieved their claimed resolution with the assistance of pixel shifting. Conceptually, the very rapid, consecutive delivery of two half-frames of video, with the second set of pixels shifted vertically and horizontally so they overlap, is seen by the eye as a single frame.