Detection device and detection method

A detection device, comprising a light source module, a receiving module which is a sensor or a charge coupled device, an image generation module which is a camera, and a judgment module which is a comparator, wherein the image generation module is connected to the receiving module and the judgment module, respectively;

• the light source module is configured to emit light towards a film at a predetermined angle;
• the receiving module is configured to receive interference light formed by first reflected light reflected by an upper surface of the film and second reflected light reflected by a lower surface of the film;
• the image generation module is configured to generate an equal thickness interference fringe image according to the interference light;
• and
• the judgment module is configured to judge whether thickness of the film is uniform according to the equal thickness interference fringe image;
• the detection device further comprises a conversion module which is an analog-to-digital converter, wherein the conversion module is connected to the image generation module and the judgment module, respectively;
• the conversion module is configured to convert the equal thickness interference fringe image into digital signals in a case where the equal thickness interference fringe image comprises an analog signal;
• and
• the judgment module is configured to compare the digital signals of the equal thickness interference fringe image with digital signals of a standard equal thickness interference fringe image, so as to judge whether the thickness of the film is uniform.