A lot of western developments in light fitting design have been going on in Halogens. Compact, low voltage LEDs can now slip neatly into some Halogen fittings. Halogen bulbs are smaller and of lower voltage, but not much more efficient than incandescents. They have never really taken off in Japan, and especially not in domestic application, where more efficient fluorescents have been standard since the 1970s. Many foreigners have been taken aback when they first visit a Japanese house and see the kind of lights that would only appear in shops and offices in the west.
There is an interesting article here on i news about new lighting technology.
I've been keenly watching the development of LEDs for domestic lighting over the last few years, but most of what I have seen is the production of LEDs in conventional light bulb packages.
Early in the development of incandescent lighting, a conscious decision was made to limit the lifetime of the light bulbs, in order that new bulbs could be sold. Hence the invention of lightbulb fittings, and replaceable lightbulbs. In many cases for LED lights, the life expectancy is as long as the building, or at least as long as the furnishings, so there is no need for a replaceable LED.
To have a replaceable LED light bulb would be like using a typewriter keyboard for a computer. This would be ridiculous because the QWERTY typewriter keyboard layout was designed to slow down the typist and stop mechanical keys jamming. Wait a minute, we do use typewriter keyboards for computers!
Moral of the story: packaging is of much higher priority than performance.
