The "Raw Streams (C#)" and "Raw Streams (C++)" sample demos support IR, but it's not obvious at first. The IR is switched off by default in the demo. To activate it, go to the "IR" menu at the top of the demo window and select an IR resolution from the menu. This will enable IR in the Raw Streams demo and un-ghost the IR radio-button option at the side of the app window, which was previously unselectable.
Left-click on the IR radio-button and then click the "Start" button and you will be shown an IR view of what the camera is seeing.
The Raw Streams demos can be accessed from the Sample Browser interface that comes with the SDK, or directly from the "RSSDK > Bin" SDK folder in which the samples are stored.