Kit to detect coronavirus on doorknobs, laptops goes on sale in Japan

The company, based in Kyoto Prefecture, said it aims to sell a thousand test kits annually.

Yikes. Good luck with that. Cleaning a surface is much much cheaper than having it tested.

Each kit can conduct 100 tests and costs 302,500 yen. The company, based in Kyoto Prefecture, said it aims to sell a thousand test kits annually.

Not free in a pandemic?

the virus lives up to 72 hours on plastic, 48 hours on stainless steel and 24 hours on cardboard.

Really? Depending on conditions, SAS-CoV-2 can survive up to 20 days in a dark cool place, like a storeroom.

You test people, not surfaces.

You clean / disinfect surfaces.

Typical Japanese indirectness

Easier to test a keyboard in Japan than a person.

As a tool to prevent infections is too slow and expensive to be of any use. It would be easier, faster and cheaper just to assume everything is contaminated and disinfect the surfaces.

The only purpose I can think of is to indirectly test for infection from someone that won't cooperate, if you cannot test the person (is not available, refuses, etc.) you can at least try and test the surfaces the person interacted with and get indirect evidence of the infection.

Something similar was developed a year ago, but with a self-cleaning function

https://thecommonwealth.org/media/news/young-jamaican%E2%80%99s-invention-could-help-tackle-spread-viruses-covid-19