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The coded aperture compressive temporal imaging (CACTI) modality is capable of capturing dynamic scenes with only a single-shot of a 2D detector. In this Letter, we present a specifically designed CACTI system to boost the reconstruction quality. Our design is twofold: for the optical encoder, we use complementary codes instead of random ones as widely adopted before; for the reconstruction algorithm, an untrained neural network-based algorithm is developed. Experimental and simulation tests show that such co-design of encoding-decoding produces superior image quality over other CACTI schemes using random codes and other optimization algorithms. In addition, a dual-prism design in the optical system improves the light efficiency by approximately a factor of four compared with previous systems.

We demonstrate the feasibility of bidirectional image transmission through a physically thick scattering medium within its memory effect range by digital optical phase conjugation. We show the bidirectional transmission is not simply the consequence of optical reciprocity. We observe that when the spatial light modulator (the device performing the digital optical phase conjugation) is relayed to the middle plane of the medium, the memory effect will be fully exploited and thus the transmitted images will have maximum field of view (FOV). Furthermore, we show that the FOV can be expanded n times by performing n times wavefront measurements.

Light focusing in multiple scattering circumstances is important in biomedical imaging, manipulation, and therapy. Until now, many traditional photorefractive crystals have been used to generate an optical phase conjugated wavefront in an analogue time-reversed optical focusing technology. However, owing to erasure of a volume hologram during a reading procedure, the optical energy gain can never reach unity, limiting its application in delivering more energy into a target area. In this work, we investigated a gated two-color photorefractive crystal LiNbO 3 : Cu : Ce to generate optical phase conjugation of diffused light with infinite gain.