A sensor (English name: transducer/sensor) is a detection device that can sense the measured information and transform it into an electrical signal or other required form of information output according to a certain rule, so as to meet the requirements of information transmission, processing, storage, display, recording and control. It is the primary link in realizing automatic detection and automatic control.
In recent years, research on new principles, materials, and technologies in sensor technology has become more in-depth and extensive, with new varieties, structures, and applications constantly emerging. Among these, "five-fold" transformation has become an important trend in its development.
Firstly, there's the area of intelligentization. One direction involves the integration of multiple sensing functions with data processing, storage, and two-way communication. This integration can fully or partially realize signal detection, transformation processing, logical judgment, functional calculation, two-way communication, as well as internal self-testing, self-calibration, self-compensation, and self-diagnosis functions. It features low-cost, high-precision information acquisition, data storage and communication capabilities, automated programming, and diverse functions. The other direction is soft sensing technology, which combines intelligent sensors with artificial intelligence. Currently, various highly intelligent sensors based on fuzzy reasoning, artificial neural networks, expert systems, and other artificial intelligence technologies have emerged and are already being used in smart homes and other applications.
Secondly, mobility is accelerating the application of wireless sensor network technology. This technology was ranked first among the top ten emerging technologies with a profound impact on the future of human life by MIT's *Technology Review* magazine. Current research focuses primarily on routing protocol design, positioning technology, time synchronization technology, data fusion technology, embedded operating system technology, network security technology, and energy harvesting technology. To date, some developed countries and cities have applied this technology in areas such as smart homes, precision agriculture, forestry monitoring, military applications, smart buildings, and intelligent transportation.
Thirdly, miniaturization has led to the rapid development of MEMS sensors. With the increasing maturity of integrated microelectromechanical processing technology, MEMS sensors have introduced semiconductor processing techniques (such as oxidation, photolithography, diffusion, deposition, and etching) into sensor manufacturing, achieving large-scale production and providing important technical support for the miniaturization of sensors. Currently, MEMS sensor technology research and development mainly focuses on the following directions: (1) miniaturization while reducing power consumption; (2) improving accuracy; (3) realizing the integration and intelligence of MEMS sensors; and (4) developing new sensors that are cross-integrated with optical, biological, and other technical fields.
Fourthly, integration is gaining widespread attention, with multifunctional integrated sensors attracting particular interest. Sensor integration includes two categories: one is the integration of multiple sensors of the same type, where multiple sensing elements with the same function are arranged on the same plane using integration technology to form a linear sensor (such as a CCD image sensor). The other is multifunctional integration, where several different sensitive components are fabricated on the same silicon wafer to create an integrated multifunctional sensor. This type of sensor has high integration, small size, and is easy to compensate and correct, representing the main direction of current sensor integration development.
Fifth, diversification is key , with breakthroughs in new materials technology accelerating the emergence of various new types of sensors. Novel sensitive materials are the technological foundation of sensors, and materials technology research and development is a crucial means to improve performance, reduce costs, and upgrade technology. Besides traditional semiconductor materials and optical fibers, organic sensitive materials, ceramic materials, superconductors, nanomaterials, and biomaterials have become research hotspots, leading to the rapid emergence of new sensors such as biosensors, fiber optic sensors, gas sensors, and digital sensors. Furthermore, according to BCC Research, biosensors and chemical sensors are expected to be the fastest-growing segments of the sensor market, with a projected compound annual growth rate of 9.7% from 2014 to 2019.
Four key areas to watch in the future
With breakthroughs in cutting-edge technologies such as materials science, nanotechnology, and microelectronics, as well as the needs of economic and social development, these four areas are likely to become the focus of future sensor technology development.
First, there are wearable applications . According to ABI Research, the number of wearable sensors is projected to reach 160 million in 2017. Wearable devices, exemplified by Google Glass, are among the most watched hardware innovations. Google Glass incorporates more than 10 types of sensors, including gyroscopes, accelerometers, magnetometers, and linear accelerometers, enabling functions that traditional devices cannot, such as taking a photo simply by blinking.
Secondly, there's autonomous driving . Google's self-driving car project has achieved significant results in this area. Using cameras, radar sensors, and laser rangefinders installed inside the vehicle, it generates real-time traffic information about the surrounding area at intervals of 20 times per second. This information is then analyzed using artificial intelligence software to predict future road conditions, and combined with Google Maps for navigation. Global automotive giants such as Audi, Mercedes-Benz, BMW, and Ford have all begun developing autonomous driving technology, with some models nearing mass production.
Thirdly, there's the application of sensor technology in medical care and health monitoring . Numerous medical research institutions both domestically and internationally, including renowned international medical giants, have made significant progress in applying sensor technology to the medical field. For example, ROHM is currently developing an image sensor using near-infrared (NIR) light. Its principle involves irradiating a near-infrared LED with a dedicated camera element to capture the reflected light. By altering the wavelength of the near-infrared light, an image is acquired, and image processing is then used to make blood vessels and other features more clearly visible. Some research institutions have made progress in manufacturing sensors using materials that can be embedded or ingested. For instance, Georgia Institute of Technology in the United States is developing an in-vivo embedded sensor with pressure sensors and wireless communication circuits. This device, composed of conductive metal and an insulating thin film, can detect pressure changes based on frequency variations in the resonant circuit it forms. After its function is complete, it dissolves in bodily fluids.
Fourthly, industrial control . In its 2012 report, "The Industrial Internet: Breaking the Boundaries of Intelligence and Machines," GE proposed that connecting humans and machines through smart sensors, combined with software and big data analytics, could overcome the limitations of physics and materials science and change the way the world operates. The report also pointed out that by deploying the Industrial Internet, various industries in the United States could achieve a 1% efficiency improvement, and the energy sector would save 1% on fuel (approximately $66 billion) within 15 years. In January 2013, GE installed more than 10,000 sensors at a battery manufacturing plant in New York to monitor data such as temperature, energy consumption, and air pressure during production. Factory managers could access this data via iPads to monitor production.
The ICCHINA2014 Sensor/MEMS exhibition area will serve as a platform for the exchange and display of sensor products and technologies, and a window into the grand blueprint for future development. It will showcase the current state of China's MEMS and sensor industry and promote the future development of my country's sensor field.
