I have just moved to China and my apartment has these kinds of lights:
I simply cant open them! The glass can be rotated without much force, as can the inner metal ring. The outer metal ring can also be rotated but requires much more force. I don't want to break the fitting so I want to check with some experts before I try extra force.
I don't even know what the name for this type of light is.
Most likely, it should pull down, out of the ceiling with relative ease. The trim will be attached to the fixture either with some long springs, or a lot of the newer fixtures have tabs along the side that hold it in.
If it is the spring type, there is a tool called a Recessed Can Light Tool that makes re-attaching these a bit easier, though they can also be reattached using a screwdriver or needle nose pliars.
Try not to twist it to much as you might just be tieing the springs into a knot unknowningly.
Hard to tell from the pics, but sometimes you can use a suction cup to grab the bulb and rotate it in and out without removing the trim rings from the fixture. Also, in most recessed fixtures, the baffle and outer trim ring are two separate parts. The inner baffle usually just fits to the trim ring by friction, but sometimes with springs connected to the can. Guess you won't really know until you get first bulb removed and get a look inside. You should however be able to remove the bulb without taking the fixture apart.
If you can't find a suction cup, try looking for those little 1 or 2 inch suction cups with a hook attached, like the ones used to hang decorations on a window etc. These cups are often included in the bulb package of some types of small bulbs like GU style. Good luck.
