function draw_wafer(translation, angle, laser)
    d = 75; % diameter
    f = 36; % distance of flat from center
    
    a = acos(f/(d/2));  % half angle opening of the flat
    
    % build wafer in reference position and orientation
    phi = [linspace(a, pi-a, 100), linspace(pi+a, 2*pi-a, 100)];
    coordinates = [-d/2*cos(phi); d/2*sin(phi)]';
    coordinates(end+1,:) = coordinates(1,:);
    
    % rotate
    angle = angle/180*pi;
    rot = [cos(angle), sin(angle); -sin(angle), cos(angle)];
    coordinates = (rot * coordinates')';
    
    % translate
    coordinates(:,1) = coordinates(:,1) + translation;
    
    % plot wafer
    plot(coordinates(:,1), coordinates(:,2), 'LineWidth', 2); 
    axis equal
    grid on
    
    % plot center
    hold all
    plot(translation, 0, 'x', 'LineWidth', 2);
    xlim([-60, 70])
    ylim([-40, 40])
    
    % plot laser spot
    l = plot(laser(1), laser(2), 'ro');
    l.MarkerFaceColor = l.Color;
    hold off
end