It has recently been shown that AC analysis (characterization in the frequency domain) offers some useful and powerful features for the thermal analysis of small objects and microelectronic devices. Unfortunately, it is difficult to do a direct measurement because a perfectly sinusoidal heating is hard to obtain. In this paper a method is presented which uses the light of an LCD projector as heating source. Projection of computer-generated images, e.g. a rectangle with sinusoidally modulated intensity, results in an alternating heating of the structure under test. The time response is captured using an infrared camera. The first results prove the possibility of the concept, and correspond well to a simple 1-D model. With the method, space-dependent heating with any arbitrary waveform in time can be obtained, simply by changing the software of the image generator.