Well, yes, according to some researches, dj lasers can be very harmful for our eyes. So you need just avoid it. It's like staring into a flashlight or up at the sun too long. Maybe you think it can be harmless to your eyes, but it can just carry many damage to your eyes. By the way, it may dazzle you and temporarily impair your vision, leading to permanent eye damage after very short exposure. So just be careful about it.
Yes, it can be bad for the eyes to frequently see DJ lasers. This is because that the DJ lasers are usually dazzling and glaring, which is highly radiant and irritative. The eyes of human beings are very sensative to radiation and heat, frequent irritation from the dazzling DJ lasers can be a great irritation to the eyes, making the eyes feel uncomfortable, itchy, painful. A long time of frequent exposure to the DJ lasers can lead to blurry vision, poor eyesight, eye fatigue, and so on. And the iris, which is right in the front of the crystalline lenses will easily get affected, leading to iritis when the condition is serious. Therefore, avoid the DJ lasers as possible as you can, and if you have to get in touch with DJ lasers, you had better wear a pair of sunglasses with polarized lenses or some other protective eyewear.