Yeah, the dish detergent can help you clean your loved eyaglasses if you take the right steps. In the chemical boundary, there is one theory called "like dissolves like". Like you said, there is some oil splash on the surface of the glasses, and some certain chemical substance in the dish detergent can dissolve the oil splash. Of course, there will be some resultant after the reaction, and then you need put your eyeglasses under the water till the glasses is clean. Nevertheless, I suggest you take your glasses to the eyeglasses shop to wash if you have time because this way can not clean your eyeglasses totally, and the experts in the shop can help you clean them via ultrasound.