Dually modulated photonic crystals enabling high-power high-beam-quality two-dimensional beam scanning lasers

電気的に2次元ビーム走査可能な新たなフォトニック結晶レーザーチップの開発に成功. 京都大学プレスリリース. 2020-07-22.Order from chaos. 京都大学プレスリリース. 2020-11-18.Mechanical-free, high-power, high-beam-quality two-dimensional (2D) beam scanning lasers are in high demand for various applications including sensing systems for smart mobility, object recognition systems, and adaptive illuminations. Here, we propose and demonstrate the concept of dually modulated photonic crystals to realize such lasers, wherein the positions and sizes of the photonic-crystal lattice points are modulated simultaneously. We show using nano-antenna theory that this photonic nanostructure is essential to realize 2D beam scanning lasers with high output power and high beam quality. We also fabricate an on-chip, circuit-driven array of dually modulated photonic-crystal lasers with a 10 × 10 matrix configuration having 100 resolvable points. Our device enables the scanning of laser beams over a wide range of 2D directions in sequence and in parallel, and can be flexibly designed to meet application-specific demands

Linear Frequency Chirp Generation Employing Opto-electronic Feedback Loop and Integrated Silicon Photonics

We demonstrate generation of linear frequency chirps exhibiting an excursion of 50 GHz (λ0=1548nm) using an optoelectronic phase-locked loop and integrated silicon photonics interferometer (FSR=3.0GHz), demonstrating the feasibility of an integrated chip-scale frequency-modulated continuous-wave LADAR source. OCIS codes: (250.3140) Integrated optoelectronic circuit; (010.3640) Lidar.Q-LA

Color and depth sensing sensor technologies for robotics and machine vision

Robust scanning technologies that offer 3D view of the world in real time are critical for situational awareness and safe operation of robotic and autonomous systems. Color and depth sensing technologies play an important role in localization and navigation in unstructured environments. Most often, sensor technology must be able to deal with factors such as objects that have low textures or objects that are dynamic, soft, and deformable. Adding intelligence to the imaging system has great potential in simplifying some of the problems. This chapter discusses the important role of scanning technologies in the development of trusted autonomous systems for robotic and machine vision with an outlook for areas that need further research and development. We start with a review of sensor technologies for specific environments including autonomous systems, mining, medical, social, aerial, and marine robotics. Special focus is on the selection of a particular scanning technology to deal with constrained or unconstrained environments. Fundamentals, advantages, and limitations of color and depth (RGB-D) technologies such as stereo vision, time of flight, structured light, and shape from shadow are discussed in detail. Strategies to deal with lighting, color constancy, occlusions, scattering, haze, and multiple reflections are discussed. This chapter also introduces the latest developments in this area by discussing the potential of emerging technologies, such as dynamic vision and focus-induced photoluminescence