Proposal of compact multimode interference optical modulator with high extinction ratio

Abstract

We proposed a compact 1×1 multimode interference (MMI) optical modulator with a high extinction ratio. A triply coupled quantum well structure is designed for the core layer for the enhancement of the quantum-confined Stark effect, and the MMI waveguide with isolation trenches is symmetrically designed. The length of the MMI modulator is reduced by 30%, and the wavelength dependence was reduced compared with that observed in the previously reported MMI modulator. Owing to both the electroabsorption effect and the electric-field induced refractive index change in a multiple-quantum-well core layer, the extinction ratio is expected to be approximately 45 dB at an operating voltage of 3.3 V.

Adaptive fusion of multi-exposure images based on perceptron model

“…The concept of multi-exposure image fusion has been around for a long time, where different information about the same scene is obtained by varying the irradiance parameters, and then an image containing more information is synthesized using an image fusion method. In the literature [8][9], an irradiance-controlled imaging system based on a light modulator was proposed to construct multiple exposure lines with different exposure levels by precisely controlling the irradiance of a single exposure and finally reconstructing the HDR scene. The literature [10] proposes a multi-exposure image fusion method based on chunking entropy, which first chunks the images, selects the optimal chunks by information entropy, and then fuses all the optimal chunks into the final fused image.…”