A Melomind headset, a neurofeedback device with sensors that detect brain activity and help the wearer control stress and improve relaxation through exercises, is displayed during CES Unveiled at the 2018 CES in Las Vegas, Nevada, U.S. January 7, 2018. REUTERS/Steve Marcus 

French Interior Minister Gerard Collomb tests a virtual reality headsets (VR) during a visit to the 20th Milipol Paris, the worldwide exhibition dedicated to homeland security, in Villepinte near Paris, France, November 21, 2017. REUTERS/Benoit Tessier 

French Interior Minister Gerard Collomb tests a virtual reality headsets (VR) during a visit to the 20th Milipol Paris, the worldwide exhibition dedicated to homeland security, in Villepinte near Paris, France, November 21, 2017. REUTERS/Benoit Tessier 

Visitors wear VR virtual reality headsets as they attend a presentation during the Digital Day event at the Central Railway Station in Zurich, Switzerland November 21, 2017. REUTERS/Arnd Wiegmann 

Visitors wear VR virtual reality headsets as they attend a presentation during the Digital Day event at the Central Railway Station in Zurich, Switzerland November 21, 2017. REUTERS/Arnd Wiegmann 

U.S. Secretary of State Rex Tillerson puts on his translation headset during a media availability with Indian Foreign Minister Sushma Swaraj, after their meeting at the Indian Foreign Ministry, Wednesday, Oct. 25, 2017, in New Delhi, India. REUTERS/Alex Brandon/Pool 

Visitors use VR headsets as they try out "The Maze" a VR system that lets people experience driving through futuristic Tokyo, at the Tokyo Connected Lab 2017 during media preview of the 45th Tokyo Motor Show in Tokyo, Japan October 25, 2017. REUTERS/Kim Kyung-Hoon 

Visitors use VR headsets as they try out "The Maze", a VR system that lets people experience driving through futuristic Tokyo, at the Tokyo Connected Lab 2017 during media preview of the 45th Tokyo Motor Show in Tokyo, Japan October 25, 2017. REUTERS/Kim Kyung-Hoon 

Google product manager Juston Payne speaks about Daydream View virtual reality headsets during a launch event in San Francisco, California, U.S. October 4, 2017. REUTERS/Stephen Lam 

Google product manager Juston Payne speaks about Daydream View virtual reality headsets during a launch event in San Francisco, California, U.S. October 4, 2017. REUTERS/Stephen Lam 

Director Taro Kambe directs as he watches acting with VR headset during a rehearsal for ROCKET's 3D virtual reality adult film at the company's studio in Tokyo, Japan, July 31, 2017. REUTERS/Toru Hanai SEARCH "PORN VR" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. TPX IMAGES OF THE DAY 

A Virtual Reality gamer lies on the floor after he demonstrated VR JCC's virtual reality adult game "Let's Play with Nanai!" using a VR headset and a sex doll at the company's SOHO office in Tokyo, Japan, June 13, 2017. REUTERS/Kim Kyung-Hoon SEARCH "FILM VR" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. 

A virtual reality gamer lies on the floor as he demonstrates VR JCC's virtual reality adult game "Let's Play with Nanai!" using a VR headset and a sex doll at the company's SOHO office in Tokyo, Japan, June 13, 2017. REUTERS/Kim Kyung-Hoon SEARCH "FILM VR" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. 

A Virtual Reality gamer reacts as he demonstrates VR JCC's virtual reality adult game "Let's Play with Nanai!" with VR headset at the company's SOHO office in Tokyo, Japan, June 13, 2017. REUTERS/Kim Kyung-Hoon SEARCH "FILM VR" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. 

Roba, programmer of VR JCC which developed virtual reality adult game "Let's Play with Nanai!", wears VR headset while he demonstrates the game at his SOHO office in Tokyo, Japan, June 13, 2017. REUTERS/Toru Hanai SEARCH "FILM VR" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. 

Reo Kaminaga hugs a virtual reality adult game character using a VR headset and controllers during an interview with Reuters at his house in Tokyo, Japan, August 6, 2017. REUTERS/Toru Hanai SEARCH "FILM VR" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. 

Director Taro Kambe directs as he watches acting with VR headset during a rehearsal for ROCKET's 3D virtual reality adult film at the company's studio in Tokyo, Japan, July 31, 2017. REUTERS/Toru Hanai SEARCH "PORN VR" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. 

Director Taro Kambe directs as he watches acting with VR headset during a rehearsal for ROCKET's 3D virtual reality adult film at the company's studio in Tokyo, Japan, July 31, 2017. REUTERS/Kim Kyung-Hoon SEARCH "FILM VR" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. TPX IMAGES OF THE DAY 

VR headset lies on the director's seat during a rehearsal for ROCKET's 3D virtual reality adult film at the company's studio in Tokyo, Japan, July 31, 2017. REUTERS/Kim Kyung-Hoon SEARCH "FILM VR" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. 

At a studio in the Japanese capital, director Taro Kambe peers into a black headset to check a scene from his first video to make use of virtual reality technology. "I have directed hundreds of adult videos but it was my first virtual reality movie," said the 39-year-old. Japan is the worldÕs second biggest virtual reality market after the United States and the adult entertainment industry and gaming sector are turning to VR as a new way to distribute content. Some analysts have said the adult entertainment industry has helped to drive adoption of new platforms, such as Super 8 film in the 1960s, and later VHS, DVD and early online videos. REUTERS SEARCH "FILM VR" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. TPX IMAGES OF THE DAY. Matching text: JAPAN-TECH/VR 

The logo of Vive, a brand of virtual reality headset developed by HTC and Valve Corporation is seen at HTC headquarters, in Taipei, Taiwan September 21, 2017. REUTERS/Tyrone Siu 

An EDF trainer demonstrates a virtual reality (VR) headset used in EDF training sessions at Cannington Court training centre in Somerset, Britain, May 4, 2017. Picture taken May 4, 2017. REUTERS/Hannah McKay 

An EDF trainer demonstrates a virtual reality (VR) headset used in EDF training sessions at Cannington Court training centre in Somerset, Britain, May 4, 2017. Picture taken May 4, 2017. REUTERS/Hannah McKay 

A woman wears 3D headset as she listens an explanation about Nissan Motor Co's new Leaf, the latest version of the world's top selling electric vehicle (EV), during its world premiere in Chiba, Japan, September 6, 2017. REUTERS/Kim Kyung-Hoon 

Mexico's Economy Minister Ildefonso Guajardo holds his headset as he addresses the media to close the second round of NAFTA talks involving the United States, Mexico and Canada at Secretary of Economy headquarters in Mexico City, Mexico, September 5, 2017. REUTERS/Edgard Garrido 

U.S. Trade Representative Robert Lighthizer holds his glasses and the headset as he addresses the media to close the second round of NAFTA talks involving the United States, Mexico and Canada at Secretary of Economy headquarters in Mexico City, Mexico, September 5, 2017. REUTERS/Edgard Garrido 

Media and guests wear VR (Virtual Reality) headsets as they wait to taste Ruby chocolate during a Ruby chocolate launch event held by chocolate maker Barry Callebaut, in Shanghai, China September 5, 2017. REUTERS/Aly Song 

Visitors wear VR virtual reality headsets during a 4-D presentation by Samsung at the IFA Electronics Show in Berlin, Germany, September 1, 2017. REUTERS/Fabrizio Bensch 

Visitors wear VR virtual reality headsets during a 3-D presentation by Samsung at the IFA Electronics Show in Berlin, Germany, September 1, 2017. REUTERS/Fabrizio Bensch 

People try earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi TPX IMAGES OF THE DAY 

A woman tries on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

A woman tries on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

A woman tries on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

A woman (R) is helped to try on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

A woman tries on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

A woman (R) tries on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

A woman tries on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

An earphone and a headset used for virtual reality is seen at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

Earphones and a headsets used for virtual reality are seen at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

A woman (R) is helped to try on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

People try earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

A man tries on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

A man tries on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

A woman tries on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

A woman tries on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

A woman tries on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

A woman tries on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

A woman tries on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

A woman tries on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

A woman tries on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

A woman tries on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy, August 29, 2017. REUTERS/Alessandro Bianchi 

A woman tries on earphones and a headset used for virtual reality at the Venice Virtual Reality a competition during 74th Venice Film Festival in Venice, Italy August 29, 2017. REUTERS/Alessandro Bianchi 

Pablo Holcer tests out a virtual reality system made by Neurable that allows the user to control with their thoughts as the EEG headset interprets thoughts into actions in the VR environment at SIGGRAPH 2017 in Los Angeles, California, U.S. July 31, 2017. REUTERS/Mike Blake 

Pablo Holcer tests out a virtual reality system made by Neurable that allows the user to control with their thoughts as the EEG headset interprets thoughts into actions in the VR environment at SIGGRAPH 2017 in Los Angeles, California U.S. July 31, 2017. REUTERS/Mike Blake TPX IMAGES OF THE DAY 

A smartphone with a headset with Spotify logo are seen in front of a displayed Warner Music logo in this illustration picture taken July 24, 2017. REUTERS/Dado Ruvic 

A man gives instructions to a woman wearing a virtual reality headset at the 25th Euskal Encounter, a four-day party during which over 5,000 computers are linked via local and high speed internet connections, in the Bilbao Exhibition Centre, Barakaldo, Spain, July 23, 2017. REUTERS/Vincent West 

A monitor shows a view of 3D Virtual Reality headset while a model demonstrates FutureLeap's 3D VR filming system at VR/AR World during Content Tokyo expo in Tokyo, Japan June 28, 2017. REUTERS/Kim Kyung-Hoon 

A visitor wears 3D Virtual Reality headset while a model demonstrates FutureLeap's 3D VR filming system at VR/AR World during Content Tokyo expo in Tokyo, Japan June 28, 2017. REUTERS/Kim Kyung-Hoon 

A man wears virtual reality (VR) headsets at the Viva Technology conference in Paris, France, June 16, 2017. REUTERS/Benoit Tessier