Non-invasive correction of thermally induced wavefront aberrations of spatial light modulator in holographic projection.

Holographic phase-only projection technique utilizing spatial light modulators (SLM) as an active element may be intended to work in environments in which the temperature changes with time, such as outdoors or automotive applications. In order to achieve maximum possible resolution, the thermally induced aberrations of the SLM must be corrected in real time. We present the results of non-invasive determination of the SLM aberrations in holographic image projection, caused mostly by thermal strains of SLM, with the use of one fixed camera detector and iterative phase retrieval. We show real-time wavefront correction leading to experimentally proven, diffraction-limited image quality in a wide range of SLM temperatures.