At the Massachusetts institute of technology (MIT) has developed a thinner than the current market glazing of (LiDAR) LiDAR system with low cost, and not using moving parts will be more durable, the speed of the mechanical beam manipulating more 1000 times quicker than the mechanical LiDAR system. In addition, one of its advantages is available CMOS devices.

IEEESpectrum reported, lidar was conducted using laser light sensor technology, is similar to radar, but it can get higher resolution, because the light wavelength is 100000 times less than radio wavelengths. Lidar system by measuring in 3 d space of each pixels from the distance of the luminous element and which direction to form a whole 3 d model of the world.

Lidar system basic operation way is to transfer beams and to measure the light reflection signals after an object, the reflection signals back to luminous module of time, can be used to directly measure and the distance of the object. In addition, analysis reflected signals can be obtained, such as the speed of an object or material composition and other information, and finally by manipulation of the transmission of light to measure the environment of different points to form a whole 3 d model.

Including self-drive USES most of the lidar system are used laser, lens and external receiver independent free space optical element, but its mechanical design not only limit the lidar system scan rate will increase the size and complexity, and commercially available high order lidar system price between $1000 to $70000, so the cost must be the smallest applications is limited.

So MIT photon Microsystems research group (PhotonicMicrosystemsGroup) using lidar system mechanization, and integrate to the microchip, in order to in CMOS factory production.

The design of components than the lidar system is small, light and cheap, and not a lumbering motivation design and more durable, its the mechanical beam manipulating more mechanical lidar system 1000 times faster than current, is expected to accelerate the image scanning rate, therefore is suitable for small high-speed track objects accurately, for high-speed unmanned aerial vehicle dodge obstacles is quite important.

The light of the research and development of the chip is first to develop 300 mm silicon photonic (SiliconPhotonics) technology, the technology is the use of transverse section of only a few hundred nanometer silicon Waveguide (Waveguide) to form the line of light, and then to Waveguide integrated to a photon circuit on a chip.

Researchers think that silicon photonic can also use the existing CMOS wafer technologies to achieve low cost production, over the past decade, many silicon CMOS fabs also developed the exclusive photon process can produce complex and photon system.

The defense advanced research projects agency (DARPA) in the past because of a miniature and integration with silicon photonics and electronics are interested in, so in 2011 set up Electronic photonic integration of heterogeneous (Electronic - PhotonicHeterogeneousIntegration) plan, and launch large-scale optical phased array (OpticalPhasedArray) and has a wide Angle can control the beam array.

Since the electronic phased array has been used in the mechanical radio beam manipulating, therefore, optical phased array can also be a small, low-cost solid-state light of ideal solution.

As for MIT design components, including 0.5 x6mm silicon photonic chip, maneuverable, transmission and receiving phased array and the composition of germanium photodetectors.

The components of thermal phase shifter can directly make waveguide heating to make laser transmission, refractive index and silicon can depends on temperature, and phase change through the speed of light, after the laser through the waveguide will encounter on silicon is considered as the antenna grooves (Notch), then let light scattering in free space.

Due to the limited antenna spacing between 51 degrees about beam control at present, although the school technology can support to 100 degrees, but if you want to then narrow spacing must first determine the minimum reserve the silicon optical waveguide can be reduced to little more. However, currently available in the car using multiple lidar sensors achieve 360 - degree image to overcome them.

Lidar detection methods of the school is the continuous method, rather than using system can only response element transmission light time range (time - of - flight), so can reduce the interference of sunshine, can use moderate light detector at the same time, instead of the expensive and difficult to integrate to the optoelectronic platform avalanche photodetectors or photomultiplier tube.

The researchers also point out that in the chip using materials such as silicon nitride (SiliconNitride) and power output can be increased dramatically, with large phased array can also reduce the beam diffraction. As to the current challenges include how to make the silicon waveguide antenna to unity and precision manufacturing, but as the lithography technology is expected to improve manufacturing capability can also improve.