For sponsor companies, the 2020 Tokyo Olympics are a golden opportunity to develop and showcase new technologies, not only to impress foreign visitors but hopefully to provide a legacy for future generations.

With everything from a mist curtain to cool people off in the oppressive summer heat to hydrogen fuel cell vehicles and robots delivering refreshing drinks, the companies are sparing no expense as they gear up for a marketing bonanza.

Major electronics maker Panasonic Corp. aims to do its bit to spread "omotenashi," or the Japanese spirit of hospitality, with its "Green Air Conditioner," which it is trialing this summer.

The air conditioner sprays a very fine and dry mist, a mixture of water and air, which evaporates quickly and brings down the temperature in a semi-enclosed space surrounded by a stream of air dubbed the "air curtain."

(Panasonic Corp.)

Unlike conventional mist cooling systems, objects like newspapers or eyeglasses will not get wet and makeup does not wash off, according to Panasonic.

The aim is to help curb the urban heat island effect in Tokyo during the Olympic and Paralympic games, which will run from late July through early September.

The company is trialing the air conditioners at bus stops, rest areas and similar spots in Fujisawa, southwest of Tokyo, from Aug. 1 through Sept. 30.

"Hospi," another product from Panasonic, is a robot that can deliver drinks to customers and clear away dishes from tables at airports or hotel lobbies. The robot navigates around people and obstacles using high-performance sensors and mapping information stored in its memory.

(Panasonic Corp.)

Demonstrations were held at Narita airport and the nearby ANA Crowne Plaza Hotel in Chiba Prefecture, east of Tokyo, earlier this year. Panasonic hopes to see Hospi robots guiding hotel guests to their rooms and also providing them with room service.

It is also developing an automated electric-powered robot cart that can assist disabled people in wheelchairs with their luggage. The carts will follow behind with the person's bags.

Nippon Telegraph and Telephone Corp. has been developing new ways for spectators to view sports using its "Kirari!" immersive 3D telepresence technology.

The system can transmit life-sized images of athletes from the stadium to the user's remote location in real time, creating the optical illusion of actually being directly in front of the action.

Every motion -- every muscle and sinew -- of an athlete can be observed close up, and even the cheers from spectators seem to be right beside the user in the hologram-like experience.

Kenichi Minami, chief researcher in charge of the project at NTT, said, "We see a wealth of opportunities in this business, expecting the system to be used during traditional arts performances, music concerts, and other events."

Toyota Motor Corp. has a blueprint for hydrogen fuel cell vehicles or buses, which only emit water, to ride around the Olympic venues in an official capacity.

The development comes in line with the Tokyo organizing committee's goal of making the Olympics a model of a "hydrogen society."

Toyota has already delivered two fuel cell buses to the Tokyo metropolitan government and aims to raise the number to about 100 by providing some to bus companies.

The automaker also hopes to promote the Toyota Mirai -- the world's first mass-produced hydrogen fuel cell vehicle that went on sale in December 2014 -- to Olympic officials and visitors. Seen as a wave of the future by Toyota, the car has not yet seen widespread commercial use.

Toyota is also set to unveil its automated driving systems.

Masaaki Ito, general manager of Toyota's Olympic and Paralympic division, said, "We plan to propose a society well supplied by various vehicles and give visitors a sense of what the future holds."

Although the Olympics will serve as a great opportunity for companies to gain publicity, Tatsuya Nakabushi, head of the Mitsubishi Research Institute's Platinum Society Center, warned they should have longer-term marketing plans to create a true legacy.

Beyond the Olympics, the companies "need to consider development of markets and how to become pervasive in society," Nakabushi said.