A lighting apparatus has a plurality of light emission block group and a detection unit for each light emission block group, wherein light emission blocks selected from different light emission block groups are grouped as sets, and light emission blocks belonging to a same set are caused to emit light simultaneously. The grouping is such that a minimum value, in all the sets, of a detection value ratio becomes as large as possible, wherein the detection value ratio is a ratio between an amount of light due to a light emission from one light emission block belonging to a light emission block group corresponding to each detection unit, and an amount of light due to a light emission from another light emission block emitting light simultaneously with the one light emission block.