An imaging apparatus for capturing a synthesized image of a visible-spectrum image and an infrared-spectrum image implements a proper synthesis balance without amplification of the signal of the infrared-spectrum image obtained by a solid-state image sensor or attenuating the visible light incident on the image sensor. A visible light source (20) and an excitation light source (22) are provided separately. The visible-spectrum image and the infrared-spectrum image, which is based on infrared fluorescent light emitted from a fluorescent substance in response to excitation light, are captured separately by a single image sensor (12) using staggered exposure periods. A signal-processing circuit (16) synthesizes the two images. The synthesis balance is adjusted by the exposure time or the respective illumination intensities of the two light sources.
