Psychtoolbox/matlab/OpenGL stereo rendering and eye separation

Hi all,
I tried to draw a 3D dot cloud using OpenGL asymmetric frustum parallel axis projection. The general principle can be found on this website(written by Paul Bourke, calculating stereo pairs). But the problem now is that when I use real eye separation(0.06m), my eyes do not fuse well. When using eye separation = 1/30 * focal length, there is no pressure. The display is a 27-Inch 3D LED Monitor.
I don’t know if there is a problem with the calculation, or there is a problem with the parameters? Part of the code is posted below. Thank you all.

  for view = 0:stereoViews
        % Select 'view' to render (left- or  right-eye):
        Screen('SelectStereoDrawbuffer', win,  view);

        % Manually reenable 3D mode in  preparation of eye draw cycle:
        Screen('BeginOpenGL', win);

        % Set the eye seperation:
        eye = 0.06; % in meter

        % Caculate the frustum shift at the near plane:
        fshift = 0.5 * eye *  depthrangen/(vdist/100);  % vdist is the focal length, 56cm, 0.56m
        right_near = depthrangen *  tand(FOV/2); % depthrangen is the depth of the near plane, 0.4. %FOV is the field of view, 18°
        left_near = -right_near;
        top_near = right_near* aspectr;
        bottom_near = -top_near;

        % Setup frustum projection for this  eyes 'view':
        eyeside = 1+(-2*view); % 1 for left eye, -1 for right eye
        glFrustum(left_near + eyeside *  fshift, right_near + eyeside * fshift,  bottom_near, top_near, depthrangen,  depthrangefObj);         

        % Setup camera for this eyes 'view':
        gluLookAt(0 - eyeside * 0.5 * eye, 0,  0, 0 - eyeside * 0.5 * eye, 0, -1, 0, 1, 0);
        % Clear color and depths buffers:
        moglDrawDots3D(win, xyz(:,:,iframe),  10, [], [], 1);
        moglDrawDots3D(win,  xyzObj(:,:,iframe), 10, [], [], 1);

        % Manually disable 3D mode before  calling Screen('Flip')!
        Screen('EndOpenGL', win);
        % Repeat for other eyes view if in stereo presentation mode...