| 摘要 |
An optical system (10) comprising: a light source (100, 200); a photodetector (400); a first light-receiving system (103) for causing the photodetector (400) to receive first reflected light with a first angle of reflection from a surface (500); and a second light-receiving system (203) for causing the photodetector (400) to receive second reflected light with a second angle of reflection, different from the first angle of reflection, from the surface (500) is provided. Here, a first light-receiving area (120) of the photodetector (400) with respect to light, of reflected light from the surface (500), via the first light-receiving system (103) is spaced apart from a second light-receiving area (220) of the photodetector (400) with respect to light, of the reflected light from the surface (500), via the second light-receiving system (203). |
