An apparatus for efficiently coupling microwave energy to a highly dissipative load such as a plasma lamp tube. A longitudinally extending lamp tube is enclosed in a longitudinally extending non-resonant microwave chamber having a pair of coupling slots therein which are oriented perpendicular to the direction of the lamp tube. The slots are azimuthally offset in opposite directions with respect to a longitudinally extending top center line of the chamber by about 15.degree. to 20.degree., and are located near respective ends of the chambers but at different distances therefrom. Microwave energy from a pair of microwave energy generating means is coupled to the respective slots with the frequency outputs of the generating means being offset from each other by a small amount.
The present invention relates to a microwave oven including a cavity having a certain area for cooking, a magnetron installed at the outside of the cavity for generating microwave, a waveguide installed at the side of the magnetron and its end extended inside of the cavity for transmitting the microwave inside of the cavity. The microwave oven comprises a bidirectional flow channel formed inside of the waveguide for transmitting microwave selectively inside of the cavity in accordance with cooking function, a microwave plate combined to inside of the waveguide so as to be rotational for guiding the microwave to selected direction between the two direction of the flow channel, and a plasma lamp installed adjacent to the side of the bidirectional flow channel for generating radiant energy by being heated by the microwave. Accordingly the microwave oven of the present invention is capable of efficient cooking by including both convection cooking and grill cooking functions, and speed cooking by convection-performing the radiant energy of the plasma lamp.
An electrodeless lamp bulb for producing relatively high radiation output in the deep ultraviolet part of the spectrum when excited with microwave energy wherein the bulb envelope is made of synthetic quartz which is substantially water-free. This results in increased bulb lifetime, since loss of bulb transparency with exposure to deep ultraviolet radiation over time is substantially reduced. An electrodeless lamp incorporating the above-described bulb includes a microwave chamber in which the bulb is situated and means for coupling microwave energy to the chamber.
An ultraviolet radiation generating system and methods is disclosed for treating a coating on a substrate, such as a coating on a fiber optic cable. The system comprises a microwave chamber having one or more ports capable of permitting the substrate to travel within or through a processing space of the microwave chamber. A microwave generator is coupled to the microwave chamber for exciting a longitudinally-extending plasma lamp mounted within the processing space of the microwave chamber. The plasma lamp emits ultraviolet radiation for irradiating the substrate in the processing space. A reflector is mounted within the processing space of the microwave chamber and is capable of reflecting ultraviolet radiation to uniformly irradiate the substrate in a surrounding fashion. When the system is operating, the microwave chamber is substantially closed to emission of microwave energy and ultraviolet radiation.
A reflector for use in an ultraviolet or other type of lamp system having a plasma bulb. The reflector includes one or more longitudinally extending reflector panels having a characteristic shape that advantageously reflects ultraviolet radiation emanating from the bulb to provide a uniform irradiance over a relatively large surface area of a substrate. A substantial portion of each reflector panel has a characteristic shape described by the equation (x/a).sup.(2+n) +(y/b).sup.(2+m) =1, where a and b are constants and n and m are exponents that range between 0 and 2.
