as a cosine function of the viewing angle normal to the surface as such more than 70 of the radiant energy released by this resistive element is projected within 45 degrees of normal to the element surface the embedded resistive element has about 33 of the coil exposed 33 of 180 degrees from the symmetry of half a circle is about 60 degrees of total arc length from the center of the exposed coil 560 directly towards the bottom of the cooktop 2 the coil extends downward about 30 degrees on each side thus even at the extreme sides of the exposed coil more than 70 of the radiant energy released by the resistive radiant element energy over the entire exposed arc length is hitting the bottom of the ceramic glass 2 the radiant energy from the inner side of each coil 580 is exposed directly to the surface of the high thermal capacity low thermal conductivity refractory material 70 the refractory quickly heats up and becomes a thermal energy radiator 590 at nearly the same temperature as the radiant element although the refractory material 70 is a significant insulator and as such actually conducts very little heat away from the element by the stephen boltzmann law it also couples very little heat into the material from the radiant element but the radiant energy emitted secondarily and normal from the surface 70 is an effective radiator of high temperature radiant energy towards the ceramic glass plate 2 the apparatus presented in this disclosure.