Large-area sub-pixel resolution imaging using a spatial light modulator

Abstract

We report results from a proof-of-principle study investigating a technique for highresolution imaging of large fields of view (FOV). This is achieved through structured illumination of the sample from a laterally replicated spatial light modulator (SLM). By incorporating the SLM into the illumination path of an otherwise conventional microscopy imaging system, we can perform the sampling by using our illumination source instead of our areal detector (camera). The increased resolution is achieved through anti-binning or splitting of the charge-coupled device (CCD) pixels, and the extended FOV is obtained by a lateral replication technique applied to the whole illumination field. With anti-binning, we effectively exceed the sampling resolution limit set by the Nyquist theorem. Also, our lateral replication technique enables us to maintain the same FOV for the increased resolution without the need for adaptive optics or highly corrected lenses far from the optical axis. The two techniques of resolution enhancement and lateral replication of the illumination field could be employed independently, hence offering increased versatility and adaptability for specialized imaging applications. Different imaging modes can be accessed digitally, without the need to change objectives, stitch together individual frames, or move the sample. The resulting imaging modality of this system is quasi-confocal.