To solve the problem that the number of microscope parts needs to be increased to shorten the tact time needed for inspection and the man-hour needed to adjust the optical axes of the microscope parts since the photodetection area of color components of red(R), green(G), and blue(B) is 1/3 time as large as the photodetection area of a monochromatic TDI line sensor as to an outward appearance inspection device which has one color TDI line sensor fitted to a microscope part 2 capable of moving freely in an X-Y direction.

A dichroic prism 3 is fitted to one microscope part 2 and spectrally diffuses light into color components of red(R), green(G), and blue(B), which are photodetected by monochromatic TDI line sensors 32 respectively to reduce the number of microscope parts to 1/3 as large as before.