JPS60104913A - Condensing device - Google Patents

Abstract

PURPOSE:To condense light having a prescribed width and radiated from a light source into a thin beam with high energy density rigidly and economically by forming one rigid condensing device by an optical medium having a prescribed refractive index. CONSTITUTION:The light source such as an LED is placed on a focal point P of an incident surface 2 and light rays radiated from the light source P are refracted by the incident surface 2 and made incident onto glass as light rays parallel with the optical axis 6. The parallel light rays are reflected by a recessed reflecting surface 4 and condensed on a projected reflecting part 3. The projected reflecting part 3 reflects the condensed light in the direction of a light extracting port 5 as parallel light rays again. Thus, the light is condensed in the direction of the optical axis while being reflected repeatedly between the surfaces 4 and 3. The light condensed up to the diameter of the light extracting port 5 is transmitted through the port 5 and discharged to the outside. Thus, the rigid and economical condensing device is obtained.

Description

[Detailed description of the invention] The present invention relates to a light condensing device.

In general, in order to condense a light source emitted with a predetermined spread from a light source with a small light emitting surface area, which can be effectively considered a point light source, onto a narrow parallel beam, it is necessary to use multiple lenses, reflectors, slits, etc. individual optical elements,
Optical systems arranged and configured to violate predetermined geometrical conditions are used. The structure of such a device is complex, and if it is subjected to mechanical vibrations due to external factors, the relative positional relationship between the constituent elements of the optical system may become distorted. Create a structure that will not cause
Must be J.

The object of the invention is an extremely robust rigid device, which
The object of the present invention is to provide a device that condenses light from a light source with a predetermined spread into an extremely narrow beam with high energy density.

In order to achieve the above object, the light condensing device according to the present invention comprises:
An optical medium having a predetermined refractive index is provided with an entrance surface having a first curvature convex toward the incident light, and a second entrance surface provided at the center of the entrance surface and reflecting the light toward the inside of the medium. a convex reflecting section having a curvature of , a concave reflecting surface facing the incident surface and having a third curvature; It is characterized in that it has a light guide port whose diameter is smaller than the diameter of the convex reflecting section, through which the light is transmitted and output.

The present invention will be explained below based on the drawings.

In the figure, an optical glass 1 having the shape of a convex lens has a convex light incident surface 2 on one side, and a convex light incident surface 2 at the center of the optical glass 1 to reflect light into the glass with an optical axis 6 as the center. A mirror-treated convex reflecting portion 3 whose reflecting surface faces into the glass is provided, and a pre-extraction port 5 having a desired diameter centered on the optical axis 6 is provided on the convex surface facing the incident surface 2. A concave mirror 4 is formed inside the glass, with the exception of the portion shown in FIG. The entrance surface 2 is a spherical surface with a focal length f1 (radius of curvature 2f+), the convex reflecting section 3 is a spherical surface with a focal length r2 (radius of curvature 2f2), and the concave mirror 4 is a spherical surface with a focal power Flu fa (radius of curvature 2f3). Also, the focal point A of this concave mirror 4 and the convex reflecting section 3
The focal points Δ coincide with each other, and the glass surface of the pre-extraction port 5 becomes a plane perpendicular to the optical axis 6 . Further, the diameter of the convex reflecting portion 3 is selected to be such that the light reflected by the concave mirror 4 and directed toward the focal point is reflected.

Next, how to use it and its effects will be explained. At the focal point P of the entrance plane 2,
For example, place a light source such as an LED. The light rays emitted from the light source ① are refracted at the entrance surface 2 and enter the glass as rays parallel to the optical axis 6. These parallel light rays are reflected and focused by the concave reflective surface 4 toward the convex reflective section 3 . The convex reflecting section 3 reflects the light condensed thereon toward the light extraction port 5 again as parallel rays. In this way, surface 4
The light is focused toward the optical axis while being reflected by the surface 3 a plurality of times. Eventually, the light that has been focused to the diameter of the light extraction port 5 passes through the pre-extraction port 5 and is emitted to the outside.

As a modified example, when the glass surface of the pre-extraction port 5 is made into a plane obliquely intersecting the optical axis 6, the beam parallelized by the convex reflection section 3 is extracted in the direction ff1l intersecting the optical axis 6. It will be done.

According to the present invention, by selecting the pre-extraction port 5 to have a desired shape and size, it is possible to obtain a light beam that is focused in a desired cross-sectional shape and a desired size.

Furthermore, since the entire structure is made up of one rigid body, it can be manufactured robustly and inexpensively. Therefore, by using easily available light sources such as LEDs and lamps, or by using color filters in combination, it is possible to obtain a luminous flux with a strong energy density and desired wavelength characteristics.

[Brief explanation of the drawing]

The drawings are configuration diagrams of embodiments of the present invention. 1... Thick convex lens-shaped glass body 2...Incidence surface 3...Convex reflection part 4... Concave reflector 5... Light extraction port 6... Optical axis Patent applicant: Nippon Laser Optics Co., Ltd. Representative Patent Attorney Nishi 1) New

Claims (1)

[Claims] An optical medium having a predetermined refractive index is provided with an entrance surface having a first curvature convex toward the incident light, and a second entrance surface provided at the center of the entrance surface and reflecting the light toward the inside of the medium. a convex reflective part having a curvature of , a concave reflective surface facing the incident surface and having a third curvature, and a concave reflective surface provided at the center of the concave reflective surface,
and a light guide port having a diameter smaller than the diameter of the convex reflector, which transmits and outputs the reflected light from the convex reflector to the outside of the medium.