Laser Charging Technology Is Coming Closer

According to Japan's Nikkei Sangyo Shimbun, Tokyo has laser-emitting objects that can convert light energy into electricity. This will not only eliminate the need to configure charging cables for mobile phones and home appliances, but will also make it possible for electric vehicles (EVs) to charge without having to stop. This life away from charging cables could be realised by 2050.

The principle of laser charging is very simple: electrical energy is utilized to emit laser light, and the object irradiated by the laser light is then converted into electrical energy by a power generation panel. Tomoyuki Miyamoto, an associate professor at the Tokyo Institute of Technology, said that laser charging can be put into practical use as soon as possible if the efficiency and safety issues can be resolved.

 

Miyamoto's team has been able to use lasers to deliver about 10 watts of current. They can also use it to manipulate radio control systems and use lasers on the ground to keep drones in stasis. In addition, their technology can charge underwater drones as well, as it is not hindered by water.

Most of the more prevalent wireless charging technologies today use the principle of electromagnetic induction, which utilizes the magnetic field created when a coil is energized to deliver electrical energy. Wireless charging of cell phones is a practical example. While this method has a charging efficiency of around 90%, the distance between the phone and the charger must be kept within a few centimeters.

 

At longer distances, the more favored option is microwave wireless charging. This technology requires the use of electromagnetic waves of a specific wavelength. However, when charging over long distances, the transmission efficiency decreases significantly with distance, making it difficult to perform high-power transmission. In addition, electromagnetic waves can cause noise in the receiver's machine, which can easily cause malfunctions.

 

In contrast, the energy conversion rate of a laser can be maintained at about 50% when carrying out long-distance power transmission. Laser is widely regarded as a technical means to realize long-distance high-power wireless charging.

 

However, this charging method is not perfect, the safety issue is very tricky. Because the laser power is very high, once the human body is very dangerous, must ensure that the use of an unmanned environment, or the relevant places of personnel access to strict management.

 

Miyamoto said that laser charging technology can first be tried on unmanned warehouse sensors and automated guided vehicles (AGVs). Unmanned warehouse sensors are set up in all corners of the warehouse, some can also move freely in the warehouse and can be fired from the top of the warehouse laser continuously charging. The technology is expected to be operational around 2030.

 

The researchers are also attempting to charge appliances and cell phones while someone is present. They ensure safety by determining a person's location through components such as cameras and stopping the laser firing once a person approaches. Having this kind of technology will enable continuous high-power charging of electric cars with lasers to keep them moving.

 

Overseas, startups in this field have been established one after another.

 

The U.S.-based PowerLight Technologies and Sweden's Ericsson have collaborated on empirical experiments of laser wireless power supply for 5G base stations. Israel's Wi-Charge is developing wireless charging technology for IoT devices.

 

Miyamoto explains that Japan, by contrast, has made little practical progress, but there are a growing number of companies interested in the field. Miyamoto and others are working to promote information sharing through related seminars.

 

Previously, lasers have been used to make memories such as CDs and DVDs, in addition to being used in the field of information communication such as optical fibers. It has also been used to process metals by utilizing the heat-generating feature of laser focusing, which is indispensable for industry.

 

Lasers are also coming into their own in the areas of facial recognition and autonomous driving. The facial recognition function of cell phones uses infrared lasers to obtain three-dimensional features of the face to determine whether the user is the owner.

 

Automobiles can use lasers to illuminate their surroundings in autonomous driving mode to determine the shape and location of obstacles.

 

The number of scenarios in which lasers can be used continues to grow. There are attempts to utilize its high energy content for nuclear fusion power generation. High-power lasers are focused on a single point, and a fusion reaction is facilitated by compression and heating under high-density conditions. Startups in various countries are actively engaged in related R&D activities.

 

In the field of agriculture, lasers can be used to monitor plant growth and soil conditions, and can also be used to eliminate weeds and insects, thereby reducing the use of pesticides and realizing unmanned plant factories.

 

In the future, lasers will also be used in a variety of fields.