Frameless panels have an almost invisible frame. Although the acrylic goes all the way to the side of the panel a minimal line can still be seen as you can see on the pics. They are somewhat thicker than the standard panels.
Frameless panels can be used in different types of situations. They are often used in those cases a frame is not desirable. This implies that they are not often used in system ceilings but mostly as independent lighting walls. Either for signing, decoration or dimmable maximum working light environment creation.