Hypopigmented lesions are seen in
In melasma brown / grey brown macular pigmentation with well defined scalloped margins. Pigmentation darkens on sun exposure.
Lichen planus produces hyper pigmented lesions.
Pityriasis Alba produces scaly hypo pigmented macules.
Melasma
Lichen planus pigmentosus
Urticaria pigmentosa
Pityriasis alba