An optimal projection of stereo images onto an HMD screen is presented, such that the viewer can observe a real-world object or local scene of his/her interest in 3D, with the feeling of desired depth and scaling, under the minimum distortion. Taking the object or local scene of viewer's focal point as that of his/her interest, the proposed 3D viewing is intended to march the characteristics of human vision. The optimal projection is done by determining the scaling factor and horizontal displacement of the original stereo images as a function of the convergence angle of the stereo camera. In this paper, we put an emphasis on the verification of the proposed optimal 3D viewing method through experimentation.