For four decades Doraemon, a blue robot cat from the 22nd century, has been an icon of Japan's manga comic world -- but now some of its coolest sci-fi gadgets exist in the real world.

Invisibility cloaks, micro-robots and brain scanners reminiscent of the cat's "Dream TV" are just some of the cutting-edge, Doraemon-style inventions going on show at Tokyo's Miraikan museum from Saturday until September 27.

Mamoru Mori, a former astronaut who heads the museum, said the earless feline has been beloved of generations of comic fans, including his three sons who have "lived by the thought 'Doraemon will come and rescue me'."

Doraemon's world also "became the dream of many researchers and scientists, who have contributed to creating a world that is a little bit more convenient", Mori said at a media preview of the show.

One piece of gear that could be straight from the cat's gadget pouch is a "retro-reflective fabric" that makes the wearer appear invisible -- essentially a movie screen that, chameleon-style, shows the image behind the wearer.

The real-time image transmission gives the illusion that the person wearing the coat is see-through -- an innovation that has not yet been commercialised but could have a variety of applications in future.

If applied to the interior of a car, for example, it could allow drivers to effectively "see through" their doors to get a clearer view of the traffic.

"Developers also say this could be used by surgeons whose own hands block their view of the organs beneath," museum curator Asako Ogita said.

Another new gizmo on display could be inspired by Doraemon's "small light" which, when beamed at someone, shrinks them to miniature size -- a prototype "medical micro robot" that measures just three centimetres (1.2 inches).

Such micro-bots will soon be used inside patients' bodies to illuminate their innards and take pictures, administer drugs and collect tissue samples, say its developers from Ritsumeikan University in western Japan.

Another technological marvel is a brain-wave sensor that, organisers say, is reminiscent of Doraemon's "Dream TV", which helped the manga tabby glimpse other people's dreams on a screen.

The device by Silicon Valley firm NeuroSky, with a headband that measures brain waves, can tell how hard the wearer is concentrating and shows the result by bringing into a focus an image of flowers on a screen.

Despite the wonders of science on show, those who are waiting for a real-life Doraemon will have to wait just a little longer, said Shinichi Hirose, science communicator at the museum.

"However, robots that could live in harmony with humans are being developed," he said, as he pointed at another of Japan's latest inventions -- mock plants that nod in agreement as humans talk to them.

Mori said he could imagine how he might wield the latest technology. "If I wear an invisible cloak, nobody would ask me for an autograph on a crowded train," he said.