There is more than one artist named Hikari:

1.- An experimental ambient music band from Monterrey, México

2.- ＨＩＫＡＲＩ, the stage name of Japanese musician ISHIZU Takamitsu (石津隆光) born in July 2nd 1973 and based in Shizuoka prefecture. Ishizu is affiliated with tearbridge production and the indie label JOTA, debuting with them on April 1999 with the single "Jetcoaster". He has since released 4 singles and 1 album.
Besides his own musical work he is broadly known for his composition and arrangement work with bands and artists like ＴＯＫＩＯ, Every Little Thing and Ｖ６. Official web page (Japanese only): http://www.tearbridge.com/hikari/

3.- Hikari, an synthwave/trap metal/alternative artist from Indiana, United States. Born in April 2nd 2004 and started music in 2017 and going strong. Their first single to reach high fan fare was 'I'll Take You To Night City" which had started the synthwave trend with Hikari. They have dropped 1 album and 1 EP, with numerous singles surrounding these. Not only do they do music, but also do artwork for themself and others under the name "Hikari Production". Read more on Last.fm. User-contributed text is available under the Creative Commons By-SA License; additional terms may apply.