Plane discharge lamp lighting system

Abstract

A flat discharge lamp lighting system is capable of preventing fusion of a dielectric layer and a glass container which are used for separating an electrode and a discharge medium due to extreme temperature rise of an electrode part while shortening rise time of luminance in early stages of lighting in the flat discharge lamp of a barrier discharge system. This flat discharge lamp lighting system detects the temperature of the electrodes (6a, 6b) of the flat discharge lamp L, and controls to continuously or gradually reduce tube power supplied to the lamp according to the rise of the electrode temperature in start of lighting.

Description

technical field [0001] The present invention relates to a flat type discharge lamp lighting system. Background technique [0002] Conventionally, a flat discharge lamp disclosed in JP-A-11-204080 (Patent Document 1) is known as a backlight light source and lighting device for a liquid crystal display. In this conventional flat discharge lamp, for example, a light-transmitting front plate made of soda lime glass or the like, and a back substrate and side plates made of soda lime glass or ceramics are hermetically sealed integrally with, for example, low-melting glass to form a structure. Flat discharge vessel. On the inner surface of the front panel, a pair of discharge electrodes parallel to each other are provided, and the surfaces of the discharge electrodes are covered with a dielectric layer formed by thick film printing or the like. In addition, phosphors are coated on the inner surface of the rear substrate, and mercury or inert gas discharge gas is sealed in the dis...

AI Technical Summary

Problems solved by technology

The temperature of the lamp tube wall with the highest luminous efficiency is 40°C to 60°C, no matter it is higher or lower than that, the luminous efficiency of the lamp will decrease

[0005] On the other hand, as a general characteristic, the heat capacity of the glass material constituting the discharge vessel of the flat discharge lamp is relatively large, so it takes a long time for the tube wall temperature to reach a certain operating temperature.

As a result, there is a problem that the luminance rise time is slow at the initial stage of lighting, and it takes a long time to reach the specified luminance.

However, with this prior art, when the heating device is constructed using a heater, there is a problem that a heater and a heater control circuit are required, and many parts other than the discharge lighting must be added, thereby inevitably increasing the cost of the device. Amplitude increase

However, as in the lighting system disclosed in Patent Document 2, when the temperature detection part is the discharge arc column part of the lamp, the temperature detection of the electrode part cannot be carried out, so in the worst case, the temperature of the electrode part rises, and the discharge There is a possibility of melting of the dielectric layer or glass container separated by the medium

In particular, when the lamp is an enlarged lamp, the rise rate of the tube wall temperature in the central part of the lamp is very slow compared with the tube wall temperature rise rate in the electrode part, so the degree of danger increases.

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