High pressure discharge lamp lighting device and projector

Abstract

A high pressure discharge lamp lighting device can prevent the deformation of electrodes by stabilizing an arc start position of a discharge lamp under the condition of low-power operation of a high pressure discharge lamp with a mercury seal volume of 0.20mg / mm3. A lighting device which has a buck circuit (1) and a full-bridge circuit (2) can supply power to the high pressure discharge lamp (10) so as to lighten the high pressure discharge lamp. Under the condition of lightening with a rated power or a dimming power (which is about 60 to 80% of the rated power), a rectangle wave alternating current is supplied to the discharge lamp (10) for lighting. Besides, the high pressure discharge lamp can be lightened by supplying an asymmetrical rectangular wave alternated current in a driving period when the lamp is operated by electric power of 0.5P (W) or less, the maximum operation power P (W) in a steady lighting state except an initial lighting period is immediately after starting, a first polarity driving period of a rectangle wave alternating current is Ta (seconds), a second polarity driving period is Tb (seconds), the second polarity driving period Tb is 5 ms or less (Tb is less than or equal to 5 ms) and a ratio Tb / Ta of these two driving periods is 0.1 or less (Tb / Ta is less than or equal to 0.1).

Description

technical field [0001] The present invention relates to a high-pressure discharge lamp lighting device and a projector equipped with the high-pressure discharge lamp lighting device. In particular, the present invention relates to a high-pressure discharge lamp lighting device and a projector equipped with the high-pressure discharge lamp and its lighting device, wherein the high-pressure discharge lamp has a 0.2 mg / mm 3 The above-mentioned mercury has a relatively high mercury vapor pressure during lighting, for example, an AC lighting type high-pressure discharge lamp with a pressure of 110 atmospheres or more, and is suitable for use as a projection light source for projection projectors and rear projection TVs. Background technique [0002] Projection-type projectors are required to uniformly illuminate an image on a rectangular screen with sufficient color reproducibility. Therefore, metal halide lamps in which mercury and metal halides are sealed are used as light sour...

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Problems solved by technology

[0022] However, according to the above technique, when lighting a high-pressure discharge lamp, for example, when a lamp with a rated power of 180 W is lit at 90 W, the starting point of the arc is unstable no matter how the frequency is combined, and so-called flickering phenomenon and halfway off

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