Images acquired under sand-dust weather conditions are severely degraded, with low contrast and severe color shift. The reason is that, due to the influence of sand-dust particles, light is scattered and absorbed, resulting in a blurred image and low contrast; the color shift is caused by the rapid attenuation of blue light. Therefore, to solve the problem of color shift and poor visibility in sand-dust images, this paper proposes a sand-dust image restoration method based on reversing the blue channel prior (RBCP). Under the influence of the blue channel, the dark channel prior (DCP) method will fail. Therefore, the method first reverses the blue channel of the sand-dust image and uses the dark channel prior method, which we call RBCP, and then, RBCP is used to estimate the atmospheric light and transmission map and recover the sand-dust image. The restored image shows significantly improved visibility. When estimating the transmission map, a guiding filter is used to improve the coarse transmission map, and a tolerance mechanism is introduced to modify the transmission map of bright areas in the sky to solve the problem of distortion in the sky. Finally, combined with the gray world, an adaptive color adjustment factor is introduced into the restoration model to remove the color shift. Experimental results via qualitative and quantitative evaluation demonstrate that the proposed method can effectively recover clear sand-dust images and produce results superior to those of other state-of-the-art methods.

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Silicon‐based photodetectors show attractive prospects due to their convenient preparation, high detectivity, and complementary metal–oxide–semiconductor compatibility. However, they are currently limited by low responsivity and sharp decay at sub‐bandgap wavelength. Although the aforementioned limitation can be partly solved by femtosecond laser processing, the surface defects and carrier activation rates result in a large dark current and narrow spectral response, which are unsatisfactory. Herein, rapid thermal annealing and hydrogenated surface passivation are introduced to elevate the broad‐bandgap responsivity and signal to noise ratio and to suppress the dark current. At optimal conditions, a sub‐bandgap responsivity of 0.80 A W−1 for 1550 nm at 20 V at room temperature is obtained, comparable with commercial germanium photodiodes and much higher than previously reported silicon photodiodes. Moreover, the prepared photodetector responded to spectral range from 400 to 1600 nm, with responsivity reaching 1097.60 A W−1 for 1080 nm at 20 V, which is the highest in reported silicon photodetectors. Simultaneously, the device shows competitive detectivity (1.22 × 1014 Jones at −5 V) due to the post‐processing procedures and suppressed dark current (7.8 μA at −5 V). The results show great prospects for black silicon in infrared light detection, night vision imaging, and fiber‐optic communication.

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