naked eye

1. Sight unassisted by an instrument such as a microscope or telescope. For example, These insects are too small to be seen with the naked eye. This expression was first recorded in 1664.

Example Sentences

Look to the north - you will not need binoculars or a telescope as the shower will be visible to the naked eye.

From BBC

The trees were sprouting green shoots and to the naked eye appeared healthy — the only sign of life on the side of the street where historic Janes Village homes burned and some neighbors perished.

From Los Angeles Times

Sesame was not listed as an ingredient on the packaging, and the seeds were not visible to the naked eye.

From BBC

Visible to the naked eye, it will look like an non-twinkling star in the constellation of Pisces.

From BBC

It’s these kinds of details that can only be observed with the naked eye and the human mind, the kinds of tells that are so specific that an AI program can’t pick them up.

From Salon