D-ILA is the marketing monicker given to JVC's version of the LCoS video technology found inside their video projectors. It stands for Direct-Drive Image Light Amplifier.
D-ILA (also HD-ILA) are LCOS, or Liquid-Crystal on Silicon. This projection technology can be thought of as a cross between a transmissive technology (LCD) and a reflective technology (DLP). In an LCOS design, a liquid crystal layer is mounted on top of a reflective layer. All the assorted circuitry needed for image reproduction is mounted behind this layer. Light enters the front of the chip, and is reflected off the back. If a pixel is supposed to be dark on screen, that pixel twists to block the light.
Because of how they are designed, LCOS, and HD-ILA in particular, offer far better contrast ratio performance than any current projection technology.
Nearly all current LCOS designs are 3-chip, one for each of the primary colors: red, green, and blue.
JVC has 4k digital cinema projector versions of their HD-ILA technology that can output enough light to fill a cinema's large screen (many times larger than a home theater), while outputting resolutions nearly five times that of 1080p HDTV. The first movie made completely in 4k was April Showers. 4k projectors are excellent at reproducing 1080p material as well, but thrive when given the highest-resolution information.
Sony also uses LCOS in many of their projectors. Their brand name for the technology is SXRD.