An eye health charity is recommending people learn the "20-20-20" rule to protect their sight, as lockdown has increased people's time using screens, the BBC reported.
Fight for Sight advises looking at something 20 feet away for 20 seconds, every 20 minutes you look at a screen.
Out of 2,000 people, half used screens more since Covid struck and a third (38 percent) of those believed their eyesight had worsened, a survey suggested.
The survey suggested one in five was less likely to get an eye test now than before the pandemic, for fear of catching or spreading the virus.
Respondents reported difficulty reading, as well as headaches and migraines and poorer night vision.
The research charity, which commissioned a survey from polling company YouGov, said it wanted to emphasize the importance of having regular eye tests and to remind people "the majority of opticians are open for appointments throughout lockdown restrictions."
Fight for Sight chief executive Sherine Krause said: "More than half of all cases of sight loss are avoidable through early detection and prevention methods. Regular eye tests can often detect symptomless sight-threatening conditions."
But even simple screen breaks can help to prevent eye strain, the charity suggested.
The College of Optometrists said its members should continue to provide eye care under lockdown for people who experience any eyesight changes.
Clinical adviser Paramdeep Bilkhu said the college's own research suggested just under a quarter of people noticed their vision deteriorate during the first lockdown.
UK health and safety legislation states employers must pay for eye tests for their employees if they have to use a screen for work for more than one hour a day.
In the summer, the UK Ophthalmology Alliance and the Royal College of Ophthalmologists calculated that at least 10,000 people had missed out on essential eye care in Britain.
In the most extreme cases, the Royal National Institute of Blind People said it feared some people were at risk of losing their sight because of a fear of attending hospital during the coronavirus pandemic.
