An image sensor, and an apparatus and method of acquiring an image by using the image sensor are provided. The image sensor includes a color filter having an array of a plurality of types of color filter elements, where each of the color filter elements transmits visible light in a certain wavelength band and blocks visible light outside the certain wavelength band; a photoelectric conversion cell array that detects light that has been transmitted through the color filter; and a modulator, disposed on the photoelectric conversion cell array, which changes a rate of light transmitted to the photoelectric conversion cell array based on an applied voltage.