Full-color computational ghost imaging using a chromatic LED array and image interpolation

Abstract

Computational ghost imaging has been an interesting topic for the imaging research community. However, low resolution and quality of image have been a major problem inhibiting the application of computational ghost imaging technique. In this work, we develop a chromatic 64 × 64 LED array which provides high-speed structured illumination up to 2.5 MHz for computational ghost imaging. Importantly, rather than using regular Cartesian arrangement which is commonly used in a digital camera's detection array, the LED chips on chromatic LED array we propose are arranged in a special way we refer to as basket-weave sampling. The experimental results demonstrate that our proposed arrangement outperforms Cartesian arrangement for storing high-frequency information of colored pictures, with averaged root mean squared error (RMSE) reduced by 4.6%. Meanwhile, considering the physical structure of the LED array, we propose a targeted interpolation algorithm for resulting images obtained from the experiment, and results show that our algorithm has lower averaged RMSE by 2% when compared to bilinear algorithm and by 6.4% when compared to bicubic algorithm.