A projection apparatus comprising: a light source configured to emit light; N, wherein N is a natural number, line memories that store images comprising a plurality of pixels for each line; a pixel storage unit configured to extract, from each of the N line memories, M, wherein M is a natural number, pixels at positions corresponding in the lines to store extracted N × M pixels; a light modulation element configured to modulate the light from the light source, based on an image including the N × M pixels; a projection optical system configured to project outside the light that has been modulated by the light modulation element; a first calculation unit configured to calculate a first sum (Bs) which is a sum of light intensities of dispersed lights generated when a pixel light of a target pixel in the plurality of pixels included in an input image passes through the projection optical system with an equation of B s = ∑ i = 1 N × M − 1 a R i b × P o based on distance information (R b), wherein b is a predetermined index number, between the target pixel and each of the pixels around the target pixel, a predetermined proportional constant a, and a light intensity (Po) of the pixel light of the target pixel, a and b being stored in a coefficient storage unit in advance, assuming one pixel of the N × M pixels that are stored in the pixel storage unit as the target pixel in a range of the N × M pixels, to calculate a first corrected light intensity (Pc) of the pixel light of the target pixel with an equation of Pc = Po + Bs by adding the first sum (Bs) to the light intensity (Po) of the pixel light of the target pixel; a second calculation unit configured to calculate a second sum (Bx) which is a sum, at a position of the target pixel, of each of light intensities of dispersed lights generated when each of pixel lights of pixels around the target pixel passes through the projection optical system with an equation of B x = ∑ i = 1 N × M − 1 a R i b × P i based on the distance information (R b) between the target pixel and each of the pixels around the target pixel and the predetermined proportional constant a; and a combining unit configured to calculate a second corrected light intensity (Pp) of the pixel light of the target pixel by subtracting the second sum (Bx) from the first corrected light intensity (Pc) with an equation of Pp = Po + Bs − Bx, wherein the light modulation element is configured to modulate the light from the light source for each of the plurality of pixels which is included in the input image and the second light intensity (Pp) of which has been calculated individually in the combining unit. a light source configured to emit light; N, wherein N is a natural number, line memories that store images comprising a plurality of pixels for each line; a pixel storage unit configured to extract, from each of the N line memories, M, wherein M is a natural number, pixels at positions corresponding in the lines to store extracted N × M pixels; a light modulation element configured to modulate the light from the light source, based on an image including the N × M pixels; a projection optical system configured to project outside the light that has been modulated by the light modulation element; a first calculation unit configured to calculate a first sum (Bs) which is a sum of light intensities of dispersed lights generated when a pixel light of a target pixel in the plurality of pixels included in an input image passes through the projection optical system with an equation of B s = ∑ i = 1 N × M − 1 a R i b × P o based on distance information (R b), wherein b is a predetermined index number, between the target pixel and each of the pixels around the target pixel, a predetermined proportional constant a, and a light intensity (Po) of the pixel light of the target pixel, a and b being stored in a coefficient storage unit in advance, assuming one pixel of the N × M pixels that are stored in the pixel storage unit as the target pixel in a range of the N × M pixels, to calculate a first corrected light intensity (Pc) of the pixel light of the target pixel with an equation of Pc = Po + Bs by adding the first sum (Bs) to the light intensity (Po) of the pixel light of the target pixel; a second calculation unit configured to calculate a second sum (Bx) which is a sum, at a position of the target pixel, of each of light intensities of dispersed lights generated when each of pixel lights of pixels around the target pixel passes through the projection optical system with an equation of B x = ∑ i = 1 N × M − 1 a R i b × P i based on the distance information (R b) between the target pixel and each of the pixels around the target pixel and the predetermined proportional constant a; and a combining unit configured to calculate a second corrected light intensity (Pp) of the pixel light of the target pixel by subtracting the second sum (Bx) from the first corrected light intensity (Pc) with an equation of Pp = Po + Bs − Bx, wherein the light modulation element is configured to modulate the light from the light source for each of the plurality of pixels which is included in the input image and the second light intensity (Pp) of which has been calculated individually in the combining unit.