New Chips For Old

Optoma UHD65 4K DLP Projector

- Thomas J. Norton

OPTOMA HAS BEEN IN THE projector business for years. Go to the company’s website, and you’ll see a bewildering array of models. But the UHD65 is one of the first models to make use of a new 4K DMD (Digital Micromirror Device), the core of Texas Instruments’ Digital Light Processing technology. And along with its sister model, the UHD60, it’s one of the cheapest.

The latest TI chip is actually 2716 x 1528, which isn’t native 4K (or the 3840 x 2160 UHD resolution that dominates the consumer world). But when it’s combined with pixel shifting—first displaying half of the pixels in a 4K source, then shifting the pixels in a slightly diagonal direction and displaying the other half—all of the roughly 8 million pixels in a 4K image are flashed on the screen. The timing of the shift is so rapid that the eye blends the two “frames” together. (See “Is DLP’s 4K Really 4K?” in our November 2017 issue.)

This differs from the similar shifting technique that JVC and Epson use in their LCOS and LCD “4K” projectors. Those designs use 1920 x 1080 chips. Do the math, rounding off to the nearest million, and you get 2 million pixels on the screen before the shift, then 4 million after. With TI’s new 2176 x 1528 chip, the results are 4 million pixels before the shift and 8 million after.