Lateral resolution in confocal microscope is limited by the size of pinhole. In this paper, we attempt to introduce a new method to achieve structured detection through using spatial light modulator (SLM) to improve it. SLM modulates the Airy disk amplitude distribution according to the detection function in collection arm. Instead of using CCD to capture spot images and modulate them with numerical analysis in virtual structured detection (VSD), this method uses SLM to accomplish these aims with higher imaging rates. Based on simulation and the experiment results, it can be found that coherent transfer function expands and the resolution is 1.6 times as large as that of conventional confocal microscope.

To improve the imaging speed of a confocal microscope with virtual structured detection, we have designed an optical system with rigid coordination control of the CCD, galvanometer scanner, and laser diode. In this system, the width of the coherent transfer function expands, which enhances the lateral resolution by a factor of 1.4. Also, the temporal image sequence is transformed to a spatial one so that multiple images can be acquired during a single exposure period of the CCD. This method increases the system imaging speed 25-fold at least, and an even higher speed can be achieved by further increasing the number of spots recorded during a single exposure period.

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