The present solar energy concentrator is a 2-dimensional system that incorporates with a tubular absorber. A new design theory is developed on the basis of the generalized edge-ray principle. The result shows the increase of concentration ratio for the same acceptance angle as the basic CPC by a factor of $C_{new}=C_{cpc}{1+(d/{pi}r);sin^2{ heta}_c}$. For example, if ${ heta}_c=30^{circ}$, the new design offers the concentration of $2.0{sim}2.72$, whereas $C_{cpc}=2$. The new system also provide a thin and light-weight design.