Yes, you can
Though there are vision requirements for people who enjoy army, but you can wear eyeglasses or contact lenses. As long as your corrected vision reach their vision standard, you can join in. Anyway, you can see there are police officers who wearing eyeglasses while they are on duty. If you are interesting it, you can get more information at https://www.peaceofficerjobs.com. Good luck.
The police officer is a great career. Generally speaking, the police can not wear glasses, because sometimes it is not very convenient for police to go for mission with glasses, and glasses even will be the key to the criminal to harm police. However, some of the police civilian staff do not have vision requirements, because they don't require a mission to go out, but do some civilian work in the office. But it depends on your mind which kind of police you want to be. If you want to go out for a mission, I suggest that you can go for an eye operation.
Generally speaking, it depends on what department and the position you choose.If you choose to be as a civilian,there is no limition that you can't wear glasses.To the limition, just when you are in medical test, there is a limition whether you can wear glasses or not, and the standards are different every year. With the years going by, more and more police officer are wearing glasses. So,you don't worry the sight with wearing glasses, you just need to pay attention to the department rule.
According to your situation that you're a little near sighted but you want to become a police officer, I think you can definitely wear glasses. You can't perform your duty well enough if you can't even see things clear. However, I strongly suggest you to replace your glasses with the contact lenses. It is more convenient and concise and can help you do better when you need to do some physical actions. Hope this will be helpful.