JPH0659801U - Light guide device for illumination in magnifying image pickup device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a light guide device for illumination that can obtain the optimal illumination light quality and illumination illuminance for a subject. [Structure] The light emitting ends of the optical fibers 1 arranged in a ring shape are made to face each other on their inner surfaces, and the inner reflection surface is plated or coated to improve the surface reflectance and an opening for illuminating a subject on the central optical axis thereof. The light guide cap 2 provided with the portion 3 is provided.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a light guide device for illumination in an enlarged image pickup device.

[0002]

[Prior art]

 The illuminating device of the magnifying image pickup device illuminates with direct illuminating light emitted from a conventional optical fiber arranged in the shape of a ring around the magnifying optical system, and as shown in FIG. 1, the inner surface and the outer surface are parallel and the inner surface is parallel. In some cases, a light guide cap made of a transparent light guide whose outer surface is a pseudo spherical surface is arranged to face the end of the optical fiber to illuminate it. There is a drawback that more light is emitted in the direction perpendicular to the optical axis.

[0003]

[Problems to be solved by the device]

 In the illumination light guide device using the conventional light guide cap 2 made of a transparent light guide shown in FIG. 1, the light incident from the optical fiber 1 is totally reflected in the light guide cap as shown in the figure. Since the light propagates through and is emitted from the opening 3 in the center, there is no illumination light other than the end face of the opening, and the illumination light has many components in the direction perpendicular to the optical axis. Further, since total reflection is used, there is a problem that the illuminance of the illumination is lowered because the light is not totally reflected and scattered due to scratches and stains on the surface of the transparent member. The problem to be solved by the present invention is to provide an illumination light guide device capable of obtaining optimal illumination light quality (parallel light, random light or mixed light thereof) and illumination illuminance for a subject.

[0004]

[Means for Solving the Problems]

 The present invention was made in order to solve the above-mentioned problems, and an optical fiber for enlarging and arranging an optical fiber for guiding illumination light in a ring shape around the optical system is provided so as to face the end face from which the light is emitted. In a magnified imaging device that has a light guide cap for illuminating the subject with the above-mentioned light, the inner surface of the light guide cap is plated or coated to improve surface reflection, and the center optical axis of the subject illuminates the subject. In addition to providing an opening for the inner surface of the cap, the shape of the inner surface of the cap is a spherical surface, an aspherical surface, an off-axis spherical surface, an off-axis aspherical surface, a pseudo spherical surface, or a surface processed into a multi-plane surface. The light emitted from the optical fiber is projected and the light reflected from the inner surface and a part of the direct illumination light emitted from the optical fiber arranged in a ring shape are emitted from the opening, and the emitted light is used as the illumination light for the subject. You Things an illumination light guide device in the enlarged image pickup apparatus according to claim.

[0005]

【Example】

 FIG. 2 shows Example 1 in which the inner surface of the light guide cap 2 is off-axis to form a rotating spherical surface. Therefore, the light guide cap 2 is formed by molding plastic, and the inner surface of the light guide cap 2 is plated and the central portion is opened. The portion 3 is formed so that the light emitted from the ring-shaped optical fiber 1 is applied to the inner surface of the light guide cap 2. In the case of this embodiment, since it is reflected by the spherical surface, it does not collect much light and illuminates a relatively wide range at a wide angle. Therefore, for example, even if soft skin rises in the opening 3, it is well illuminated. FIG. 3 shows Example 2 in which the inner surface of the light guide cap 21 is formed into a spheroidal surface. When the end portion of the optical fiber 1 is arranged at the principal focal point F, the light reflected on the inner surface is focused on F ′. This is effective when high-magnification observation or illumination at a wide angle is required. FIG. 4 shows Example 3 in which the inner surface of the light guide cap 22 is a paraboloid of revolution, and when the end of the optical fiber 1 is arranged at the principal focal point F, parallel illumination is achieved, which is suitable for illumination over a wide area. Moreover, since the illumination angle is constant, for example, illumination suitable for distinguishing the color of the subject can be obtained. In FIG. 5, the inner surface of the light guide cap 23 is multi-planar. By selecting the ratio of each surface, illumination suitable for the subject can be obtained.

[Effect of device]

 According to the present invention, by selecting the inner surface shape of the light guide cap 23 as spherical, aspherical surface, off-axis spherical surface, off-axis aspherical surface, quasi-spherical surface, or multi-planar surface, the optimum light quality of illumination for the subject is obtained. Can be obtained. In addition, it is possible to minimize the loss of light guided by the optical fiber from the illumination light source. When metal is used as the material for the light guide cap, it is physically strong against external shocks and safe. Furthermore, since it is a surface reflection on the inner surface, the illumination light is stable regardless of whether the material is metal or non-metal.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a conventional illumination light guide device.

FIG. 2 is a partially cutaway perspective view and a vertical sectional view of the first embodiment of the present invention.

FIG. 3 is a vertical sectional view of a second embodiment of the present invention.

FIG. 4 is a vertical sectional view of a third embodiment of the present invention.

FIG. 5 is a vertical cross-sectional view of Embodiment 4 of the present invention.

[Explanation of symbols]

 1 Optical fiber 2, 21, 22, 23 Light guide cap 3 Opening

Claims (1)

[Scope of utility model registration request] 1. A light guide for illuminating a subject with an optical fiber for enlarging and arranging an optical fiber for guiding the illuminating light around the optical fiber in an annular shape, facing the end face from which the light is emitted. In a magnified imaging device having an optical cap, the inner surface of the light guide cap is plated or coated to improve the surface reflectance, and an opening for subject illumination is provided on the central optical axis of the light guide cap, and the inner surface of the cap is also provided. The shape of the spherical surface, the aspherical surface off-axis spherical surface, the off-axis aspherical surface, the pseudo spherical surface, any one of the surfaces processed into a multi-plane as a reflecting surface, and the light emitted from the optical fiber is projected onto the reflecting surface. Illumination in a magnified image pickup device characterized in that the internal surface reflected light and a part of the direct illumination light emitted from an optical fiber arranged in an annular shape are emitted from the opening, and the emitted light is used as a subject illumination light. for Light guide device.