Image acquiring device and image acquiring system

An image acquiring system, comprising:

• a flying object;
• a GPS device mounted on said flying object;
• a control device for controlling flight of said flying object;
• a first camera mounted on said flying object and for acquiring video images made up by frame images continuous to each other in time series;
• a second camera having an optical axis in common with said first camera and provided in a known relation with said first camera and for acquiring two or more optical spectral images with different wavelengths of an object to be measured;
• and an image pickup control device, wherein each pixel of image pickup elements of the first camera corresponds to each pixel of image pickup elements of the second camera in a one-to-one relation and said flying object moves from a first point to a second point, said GPS device measures a position of the first point and a position of the second point in geocentric coordinate system, said first camera acquires a still image of the first point, acquires video images during the moving from the first point to the second point, and further, acquires still images at the second point, wherein said second camera comprises an optical system which has a tele-centric optical system as a wavelength changing means and an interference filter tilted with respect to an optical axis of said second camera, wherein a diaphragm of said tele-centric optical system is provided so as to be movable along a direction perpendicular to said optical axis, and by moving said diaphragm and changing an angle of luminous fluxes entering said interference filter, said second camera acquires two or more optical spectral image in a predetermined wavelength range including two or more different wavelengths, and wherein said image pickup control device extracts two or more feature points from the still image at the first point, performs video image tracking from the video image during the moving from the first point to the second point, specifies said feature points in the still image at the second point, performs stereo-matching of the still image at the first point with the still image at the second point based on said feature points, prepares a three-dimensional model based on positions of said first point and said second point in the geocentric coordinate system, and said image pickup control device synthesizes two or more optical spectral images with different wavelengths, prepares an optical spectral synthetic image based on the condition of stereo-matching, synthesizes said three-dimensional model with said optical spectral synthetic image, and prepares a four-dimensional model having three-dimensional position data and optical spectral information of said object to be measured.