1. A distance estimation apparatus that illuminates an object with light having a modulated light intensity and estimates a distance to an object using reflected light from the object, the apparatus comprising: a light source operable to emit light whose light intensity can be modulated; a light source control unit operable to control the light source; a light receiving optical system operable to focus light from the object; a color separation unit operable to separate light received by the light receiving optical system into a first light component and a second light component based on a frequency of the light; a light receiving unit operable to convert the second light component separated by the color separation unit to obtain charge; a charge accumulation unit operable to accumulate the charge obtained by the light receiving unit and obtain a charge signal; a signal processing unit operable to calculate distance information based on the charge signal; a distance image generation unit operable to generate a distance image having a first number of pixels based on the distance information; an imaging unit operable to convert the second light component separated by the color separation unit to an image generation charge signal; a high resolution image generation unit operable to generate a high resolution image having pixels more than the first number of pixels based on the image generation charge signal obtained by the imaging unit; an edge information extraction unit operable to extract edge information from the high resolution image generated by the high resolution image generation unit; and a distance image correction unit operable to correct distance information of a target pixel of the distance image based on a neighboring pixel of the target pixel in the distance image and based on the edge information extracted by the edge information extraction unit.