An optical detection device, comprising: an uncooled image sensor that has a plurality of pixels configured to convert an amount of light from a detection region into an electric current; a filter configured to eliminate light in a wavelength range that is influenced by a detection target object; a filter driver configured to place or remove the filter in front of or from in front of the image sensor; and a processor configured to detect presence or absence of the detection target object by processing data from the image sensor, a connection interface; and the processor is configured to drive the filter driver to place the filter in front of the image sensor; shoot image data with the image sensor through the filter 30); correct the image data with previously stored gradient correction coefficients correcting a ratio of a change of the amount of light to a change of the electric current on a pixel-to-pixel basis such that the ratios at all pixels are equal; calculate pixel-to-pixel pixel characteristics correction coefficients for correcting the gradient corrected image data to image data estimated values which would be obtained by shooting without the filter using a spectroscopic sensitivity characteristic of the image sensor and a spectroscopic transmittance characteristic of the filter; correct the gradient corrected image data with the calculated pixel characteristics correction coefficient for each pixel to obtain image data estimated values; drive the filter driver to remove the filter from in front of the image sensor; shoot shot data with the image sensor without the filter; correct the shot data with previously stored gradient correction coefficients; compare the corrected image data estimated values with the shot data; and determine the presence or absence of the detection target object based on the comparison result, and transmits a warning signal from the connection interface if the detection target object is present, wherein a wavelength range that is eliminated by the filter includes one of a wavelength range absorbed by the detection target object and a wavelength range emitted by the detection target object. an uncooled image sensor that has a plurality of pixels configured to convert an amount of light from a detection region into an electric current; a filter configured to eliminate light in a wavelength range that is influenced by a detection target object; a filter driver configured to place or remove the filter in front of or from in front of the image sensor; and a processor configured to detect presence or absence of the detection target object by processing data from the image sensor, a connection interface; and the processor is configured to drive the filter driver to place the filter in front of the image sensor; shoot image data with the image sensor through the filter 30); correct the image data with previously stored gradient correction coefficients correcting a ratio of a change of the amount of light to a change of the electric current on a pixel-to-pixel basis such that the ratios at all pixels are equal; calculate pixel-to-pixel pixel characteristics correction coefficients for correcting the gradient corrected image data to image data estimated values which would be obtained by shooting without the filter using a spectroscopic sensitivity characteristic of the image sensor and a spectroscopic transmittance characteristic of the filter; correct the gradient corrected image data with the calculated pixel characteristics correction coefficient for each pixel to obtain image data estimated values; drive the filter driver to remove the filter from in front of the image sensor; shoot shot data with the image sensor without the filter; correct the shot data with previously stored gradient correction coefficients; compare the corrected image data estimated values with the shot data; and determine the presence or absence of the detection target object based on the comparison result, and transmits a warning signal from the connection interface if the detection target object is present, wherein a wavelength range that is eliminated by the filter includes one of a wavelength range absorbed by the detection target object and a wavelength range emitted by the detection target object.