A display device having a liquid crystal display element (30) transmitting light projected from a light source to an watching point side, and including pixels (31) forming a first image region and a second image region, and an image separation filter (32) disposed from the pixels (31) through glasses (33, 34) each with a specified thickness and forming a first image separation mechanism and a second image separation mechanism, in which a calculation for obtaining the disposing interval (P1, P3) of each of the above-described image separation mechanisms of the image separation filter (32) is carried out on the basis of angles of elevation k+1, k, angles k+1, k, thicknesses W1, W2 and refractive index n of the glasses (33, 34), a distance D from the watching point to the display device, and an interval (P2) between the image regions of the above-described pixels (31) to dispose the image separation mechanisms of the above-described filter (32) with the obtained P1, P3.