They do have a yellow filter which, filling the lens, absorbs ultraviolet light, protecting the eye. Nocturnal reptiles usually have smaller eyes than diurnal ones, but relatively large pupillary and lens aperture and cornea. This improves their light-gathering ability, but at the same time reduces visual acuity. Lizards can focus on near and far by squeezing or stretching their lenses, using the ciliary muscles and annular pads. Pupils dilate and contract in response to light.
Some nocturnal lizards have slit pupils, others are round.
Lizards, unlike other reptiles, have a choroid body, called the conus papillaris. Projecting out into the vitrious humor, it nourishes the cornea. Croom Helm, London. Grace, Michael S. 1997, The visual system and non-visual photoreception. Lowell Ackerman, DVM, ed.