Light emitting device

Abstract

The invention provides a light emitting device comprises a first unit and a second unit. The unit comprises a laser element emitting blue wavelength band excitation light; a first wavelength converting member comprising at least one type of fluorescent material and which absorbs at least a portion of a first excitation light emitted from the first excitation light source, converts the wavelength, and releases light with a wavelength longer than the first excitation light; and a first light guide which has a refractive index in the center region of the cross-section which is higher than the refractive index of the surrounding region and which transmits the first excitation light emitted from the first excitation light source; and the second unit comprises a second excitation light source, a second wavelength converting member , and a second light guide. According to the invention, combining the laser element emitting blue wavelength band excitation light and another laser element can perform excellent color rendering.

Description

technical field [0001] The present invention relates to a light emitting device, in particular to a light emitting device mainly comprising an excitation light source, a wavelength conversion component, and a light guide. Background technique [0002] Conventionally, endoscope devices for observing the inside of a living body or performing treatment while observing, or fiberscopes for observing very narrow or very dark spaces have been widely used. [0003] An endoscope or a fiberscope is composed of a very thin light guide, and by sending light irradiated from a light source into the fiber, it is possible to illuminate a space such as a body cavity such as the stomach or a gap. [0004] In order to perform high-efficiency lighting using thin fibers, high luminance is required for the light source. In addition, in order to observe an affected part of an internal organ, a gap, etc., and perform a diagnosis at the same time, it is important to accurately reproduce color infor...

AI Technical Summary

Problems solved by technology

[0010] In particular, in the case of using a semiconductor laser that emits blue wavelength light, due to its characteristic properties of the laser, that is, it has a line spectrum in the blue wavelength region, and in its peripheral wavelength region (for example, near ultraviolet region and cyan The relatively wide range of the green wavelength region), the property of extremely reducing the luminous intensity, cannot fully meet the requirements of color rendering

[0011] In addition, depending on the application of the light source device, extremely high luminance is required, but since luminous efficiency, luminance, and color rendering have such a selective relationship with each other, it is difficult to fully satisfy the requirements of both luminous efficiency and color rendering

[0012] In addition, semiconductor light-emitting elements such as semiconductor lasers require higher luminance and higher luminous efficiency, but generally, due to their high optical density, resins and fluorescent substances constituting wavelength conversion components are damaged by high-density excitation light. Heat generation and deterioration may lead to a reduction in the life of the light emitting device itself

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