An optical measuring apparatus comprises: an illuminating section that illuminates a first object with a first light; a light changing section that changes an intensity of the first light illuminating the first object; a light receiving device that receives a second light transmitted through or reflected from the first object; and an output section that outputs a measurement result according to i) a state of the light changing section and ii) an amount of the second light received by the light receiving device. In addition, an optical measuring apparatus comprises: the illuminating section; the light receiving device; a light receiving time changing section that changes a light receiving time of the light receiving device; and an output section that outputs a measurement result according to i) the light receiving time and ii) an amount of the second light received by the light receiving device.