Exterior inspection apparatus and exterior inspection method

An exterior inspection apparatus that picks up an image of an object being inspected and inspects an exterior of this object, comprising:

• a plurality of filters that are provided in stages for differing transmission wavelengths and are positioned so as to face the object being inspected, and that only transmit a specific wavelength from an optical image of the object being inspected;
• an image pickup device that picks up an optical image transmitted through the filter and outputs image data for each wavelength region;
• an image processing device that creates spectrum characteristic data by analyzing differences between contrast ratios by using a comparison of the image data output for each wavelength region, and then specifies a substance based on the spectrum characteristic data;
• and
• a database device on which the image data and the spectrum characteristic data are readably recorded as case information,
• wherein the image processing device comprises:
• a substance specifying section that, by reading the case information recorded on the database device and comparing this case information with the image data and spectrum characteristic data of the object being inspected, is able to specify the class of the object being inspected and then output classification information and distribution information;
• and
• a search processing section that searches for and extracts the image data and the spectrum characteristic data that are recorded as case information on the database device.