Korean researchers have developed a core chip for three-dimensional (3D) image sensors which function as the “eye” of autonomous vehicles, drones, and robots. In the future, the chip will be mounted on smart phones and used for various services, such as face recognition and augmented reality (AR).
The Korea Advanced Institute of Science and Technology (KAIST) announced on Jan. 22 that a team led by Prof. Park Hyo-hoon of the Department of Electrical Engineering has developed the silicon-based optical phased array (OPA) chip, which is a core technology for 3D image sensors, in collaboration with the National Nanofab Center.
A 3D image sensor adds distance information with cubic effect to a 2D image such as a photograph to make it recognized as a three-dimensional image. It is a core part that acts as an eye for various electronic devices such as autonomous vehicles, drones, and robots that require accurate distance information of objects.
OPA has been attracting attention as the next generation structure of LiDAR, which is a 3D image sensor that uses laser light. The research team developed the OPA device, which electrically controls the direction of light, based on silicon in a small-size, durable form. However, while OPA can scan in the horizontal direction, it has a technical difficulty of changing the wavelength of the laser light in order to scan in the vertical direction.
The team developed an ultra-small, low-power OPA chip that is capable of wide-range 2D scanning by turning light into a single wavelength light source that can be easily adjusted in vertical and horizontal direction by advancing the conventional OPA, which uses a wavelength-modulated light source.
The chip can be made as small as the size of an eye of a dragonfly, leading to the miniaturization of the 3D image sensor. In particular, the research team explained that in addition to the function of 3D image sensor, it can also carry out the function of wireless transmission of acquired 3D image data in a desired direction, which leads unrestricted communication of high-resolution and high-capacity image information between electronic devices.