An electronic device has an optical lens. The optical lens includes in order from an object side to an image-forming side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens. The second lens and the third lens have negative powers respectively, and the fourth lens, the sixth lens, and the eighth lens have positive powers respectively. The first lens is a plastic lens. The object-side surface of the first lens is a convex, surface and/or the image-side surface of the first lens is a concave surface. The sixth lens and the seventh lens are made into a doublet lens.