A zero voltage switch half bridge converter comprises a first and second diode series diodes, parallel with a voltage source. The target surfaces are engageable with the base game-playing structure in one or more substantially vertical orientations and configured to receive passed projectiles. The display panel has a plurality of pixels for selectively outputting light output from the optical element array. Specifically, it is preferred that the contrast CR of the red color pattern 10R, the contrast CG of the green color pattern 10G, and the contrast CB of the blue color pattern 10B fulfill the relationship CR<CG<CB, as well as the relationship CR:CG=1.