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We propose a novel full-electronically controlled laser confocal microscope in which a liquid-crystal-on-silicon spatial light modulator and a custom CMOS imaging sensor are synchronized for performing multi-beam confocal imaging. Adaptive wavefront modulation for functional multi-beam excitation can be achieved by displaying appropriate computer generated holograms on the spatial light modulator, in consideration of the numerical aperture of the focusing objective. We also adopted a custom CMOS imaging sensor to realize multi-beam confocal microscopy without any physical pinhole. The confocality of this microscope was verified by improvements in transverse and axial resolutions of fluorescent micro-beads.

In this paper, a pseudo 2-transistor active pixel sensor (APS) has been designed and fabricated by using an n-well/gate-tied p-channel metal oxide semiconductor field effect transistor (PMOSFET)-type photodetector with built-in transfer gate. The proposed sensor has been fabricated using a 0.35 μm 2-poly 4-metal standard complementary metal oxide semiconductor (CMOS) logic process. The pseudo 2-transistor APS consists of two NMOSFETs and one photodetector which can amplify the generated photocurrent. The area of the pseudo 2-transistor APS is 7.1 × 6.2 μm2. The sensitivity of the proposed pixel is 49 lux/(V·s). By using this pixel, a smaller pixel area and a higher level of sensitivity can be realized when compared with a conventional 3-transistor APS which uses a pn junction photodiode.