Laser driven light source

Abstract

An laser driven light source comprises a bulb that encloses a discharge medium which is activated by a laser beam to generate a plasma. It is an object of the present invention to provide a shield from a laser beam, which passes through plasma generated in a bulb without being absorbed therein. A laser driven light source includes a bulb that encloses a discharge medium, wherein plasma is generated in the bulb by a laser beam focused in the bulb, and a beam shield element is provided within the bulb so as to provide a shield from the laser beam that passes through the plasma generated in the bulb.

Description

technical field [0001] The invention relates to a laser-driven light source. In particular, it relates to a laser-driven light source used as an exposure device used in the exposure process of semiconductors, liquid crystal substrates, and color filters, an image projection device for digital theaters, and a light source for optical analysis devices. Background technique [0002] In recent years, light sources used in exposure devices used in the above-mentioned exposure process, image projection devices for digital cinemas, and optical analysis devices have been required to have a long service life in addition to sufficient luminous intensity in the required wavelength region. [0003] The light source used in this field is a type in which an arc discharge is generated between electrodes in a glass tube sealed with mercury or a rare gas (xenon gas). However, since the electrodes are exposed to the arc discharge, it is difficult to avoid becoming extremely high temperature ...

AI Technical Summary

Problems solved by technology

However, the existing laser-driven light source 130 removes the electrode from the bulb 135, so the mercury in the bulb 135 cannot be fully evaporated, and the mercury vapor pressure in the bulb 135 cannot be increased.

[0013] Therefore, the existing laser-driven light source 130 has the following problems: the luminous intensity of the mercury emitted to the outside of the tube bulb 135 is extremely low, and the laser light focused to the focal point in the tube bulb 135 is basically not absorbed by the mercury vapor, but emitted to the outside of the tube bulb 135. The outside of the tube bulb 135

[0014] but in Figure 13 In the laser-driven light source 130 shown, no studies have been conducted on the above-mentioned problems caused by the low mercury vapor pressure in the bulb 135

And the above-mentioned problem is not limited to when mercury is enclosed in the bulb 135 as the metal for light emission, and of course also occurs when other metals for light emission other than mercury are enclosed in the bulb 135.

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