eye candy vs visual image

eye candy and visual image both are nouns.

Word	Noun	Adjective	Verb	Adverb
eye candy	Yes	No	No	No
visual image	Yes	No	No	No

As nouns, visual image is a hypernym of eye candy; that is, visual image is a word with a broader meaning than eye candy:

eye candy: visual images that are pleasing to see but are intellectually undemanding
visual image: a percept that arises from the eyes; an image in the visual system

Other hypernyms of eye candy include visual percept.

eye candy (noun)	visual image (noun)
visual images that are pleasing to see but are intellectually undemanding	a percept that arises from the eyes; an image in the visual system
	a mental image that is similar to a visual perception