Fluorescent lamp with different density phosphor coatings on the front panel and internal channels

A flat compact fluorescent lamp containing a fill mercury and inert gas, said lamp comprising:

• a glass front panel having an inner surface and a glass bottom panel also having an inner and an outer surface, said inner surface of said front panel being either sandblasted or coated with a film of silica or both;
• a convoluted glass partition disposed between said inner surfaces of said front and bottom panels, said partition with said bottom panel forming a channel having an initial and a terminal end, observation of the definition of said partition from said outer surface being reduced by said sandblasting or with a silica film when the lamp is operating;
• means to seal the peripheral portion of said convoluted partition to the inner surface of said front panel, said sealing means forming a sealed envelope with said front and bottom panels;
• a phosphor coating on the inner surface of said channel, said coating being of predetermined density;
• a phosphor coating on the inner surface of said front panel, said coating being of predetermined density, said density being significantly less than the density of the coating on said channel;
• at least two electrode means for said lamp, one of said electrode means being disposed at the initial end of said convolution and the other being disposed at the terminal end, whereby to emit radiation and excite said phosphor to emit light, substantially all the light emerging from the coating on said channel passing through the coating of phosphor on said front panel.

A flat compact fluorescent lamp containing a fill mercury and inert gas, said lamp comprising:

• a glass front panel having an inner surface and a glass bottom panel also having an inner and an outer surface, said inner surface being either sandblasted or having a film of silica or both;
• a convoluted glass partition disposed between said inner surfaces of said front and bottom panels, said partition with said bottom panel forming a convoluted channel having an initial and a terminal end, observation of the definition of said partition from said outer surface being reduced by said sandblasting or said film of silica when the lamp is operating;
• means to seal the peripheral portion of said convoluted partition to the inner surface of said front panel, said sealing means forming a sealed envelope with said front and bottom panels;
• a phosphor coating on the inner surface of said convoluted channel, said coating being of predetermined density;
• a phosphor coating on the inner surface of said front panel, said coating being of predetermined density, said density being significantly less than the density of the coating on said convoluted channel said predetermined density of the phosphor on said channel being between about 3 and 5 mg./cm.sup.2 and said predetermined density of the phosphor on the inner surface of said front panel being between about 0.5 and 1.5 mg./cm.sup.2.;
• at least two electrode means for said lamp, one of said electrode means being disposed at the initial end of said convolution and the other being disposed at the terminal end, whereby to emit radiation and excite said phosphor to emit light, substantially all the light emerging from the coating on said channel passing through the coating of phosphor on said front panel.

A flat compact fluorescent lamp having a generally circular viewable face and containing a fill mercury and inert gas, said lamp comprising:

• a generally circular glass front panel having an inner surface and a generally circular glass bottom panel also having an inner surface;
• a spiral glass partition disposed between said inner surfaces of said front and bottom panels, said partition being integrally molded to said bottom panel, said partition being formed of a circular outer ring portion and an inner convoluted portion, said partition forming a spiral channel having an initial end and a terminal end and a housing for an electrode means disposed at said initial end and said terminal end, said channel having a substantially uniform width throughout its length and being formed eccentrically with a series of smooth, gradual lobes commencing in the first convolution of the partition and extending outwardly through successive convolutions and terminating within said outer ring portion;
• means to seal the ring portion of said convoluted partition to the inner surface of said front panel, said sealing means forming a sealed envelope with said front and bottom panels;
• a phosphor coating on the inner surface of said convoluted channel and a phosphor coating on the inner surface of said front panel, the coating on said front panel being of predetermined density, said density being significantly less than the density of the coating on said convoluted channel;
• an electrode means for said lamp disposed in each of said housings to ionize and excite the mercury and produce photons to excite the phosphor.