It marks the first anniversary of the massive earthquake and resulting tsunami that devastated Japan and caused a nuclear disaster.
Hongkongers Kastia Chan, Jerry Zhang, Monica Shing, Carmen Chow and Emmy Wong were in Tokyo studying Japanese as the 9.0-magnitude quake struck off the northeast coast. It created a huge tsunami that killed 15,850 people, injured 6,011 others and left a further 3,287 people missing.
A power failure at Fukushima Daiichi nuclear plant, caused by the tsunami, led to the failure of cooling systems and the meltdown of three nuclear reactors. Harmful radioactive particles escaped.
The students set up the contest with the help of the Japan National Tourism Organisation and the Consulate-General of Japan.
They were on an exchange programme at the time of the disasters and the experience remains vivid in their memories.
"I was at the dormitory when the earthquake struck and I was very nervous," says Chan, 22, a fourth-year student at the university's Department of Japanese Studies.
"It was the first time I'd experienced such a big earthquake, and my family and friends were very worried about me. The earthquake had a special meaning for all five of us. We witnessed it and shared the sorrow of Japanese people. We sincerely hope Japan recovers soon.
"The contest can provide a platform for people to share their travel experiences - and hopefully boost tourism and revitalise Japan."
Anyone can submit a photo - with a short caption - taken while visiting Japan.
Prizes include two round-trip tickets to Tokyo, a Japanese digital camera and food hampers. Winning entries will be displayed in Kowloon Bay International Trade and Exhibition Centre between March 23 and 27.
There is also a Facebook page: on.fb.me/japanendlessdiscovery.