Low voltage mercury vapous discharge lamp, illuminating apparatus and display device

Abstract

The invention discloses a low pressure mercury vapor electric discharge lamp (1) by steam, which is respectively equipped with a glass-made luminous tube (2) with the wall thickness of 0.3mm and a glass-made coaxial external tube (3) with the external diameter of 3.6mm. A gap (5) of 0.1mm is arranged between the luminous tube (2) and the external tube (3). Whole sealing parts (b) are arranged on the two ends of the luminous tube (2) and the external tube (3). The sealing parts on the two ends are equipped with cold cathodes (8, 8) which are respectively connected with a dumet wire (7). The gap (5) is arranged to almost high vacuum acquiring pressure under 1Pa.

Description

Technical field [0001] The invention relates to a low-pressure mercury vapor discharge lamp, a lighting device and a display device that realizes small diameter and high efficiency. Background technique [0002] In the past, as a low-pressure mercury vapor discharge lamp using a double tube, for example, a structure described in Japanese Industrial Publication No. 4-52932 is known. [0003] In the low-pressure mercury vapor discharge lamp described in the Japanese Kokai No. 4-52932, a coaxial glass outer tube with a gap is provided around an elongated cylindrical inner tube made of glass, and two The holding member provided at the end holds the inner tube and the outer tube, and keeps the inner tube in an adiabatic state to prevent contact with the outside air. Even if the input power is small and the heat capacity is small, the luminous efficiency in the low temperature atmosphere can be suppressed from decreasing. [0004] However, when the inner tube and the outer tube are air...

AI Technical Summary

Problems solved by technology

In the above-mentioned conventional structure, although the outer diameter of the inner tube is less than 6 mm, the electrode is a hot cathode, so the small diameter is limited, and it is still difficult to make the inner diameter of the inner tube less than 3 mm.

In addition, for example, the gap is 1-10mm, especially when it is installed with the light guide plate, the gap between the inner tube and the light incident surface of the light guide plate becomes larger, and the light loss becomes larger.

In addition, it has also been considered to increase the input power of the light tube of the low-pressure mercury vapor discharge lamp in order to increase the luminance, but the input power of the light tube cannot be increased due to the decrease in the efficiency of the lamp tube.

[0006] In addition, general discharge lamps use high-frequency lighting of several 10KHz or more to improve efficiency, but it is known that once the discharge lamp for high-frequency lighting is installed on the machine, the efficiency will drop to some extent. The reason for the drop in efficiency is leakage current. As a result, the lamp tube with an outer diameter of less than 8mm is particularly obvious

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