When it comes to vision testing, no two eyes are alike, because no two people are alike. In fact, its those difference determine what types of vision testing or vision testing equipment will be used to a given examination. As I know there are 11 types of vision testing. They are visual acuity testing, visual field testing,cover testing,color-blind testing,refraction testing,slit lamp testing,tonometry (Glaucoma) Testing,The "Puffer" Test,the touch Test,dilation testing,vision testing. Hope this helpful.