JPS61230106A - Optical multiplexer device - Google Patents

Abstract

PURPOSE:To reduce the side of a device and easily adjust respective elements, and to eliminate the need for readjustments during use by converging light beams from plural laser light sources on one point by a grating lens provided on a top surface waveguide plate. CONSTITUTION:The light beams from the semiconductor lasers 1-3 are converted on one point P1 through an optical waveguide layer 4B on the substrate 4 and the grating lens 5. The lens 5 consists of parts 5A-5C having gratings which are sectioned corresponding to incidence positions of the light beams 1a-3a and differ in pitch and direction from one another, and the incident light is diffracted, converged on the point P1 and made into parallel light through a collimator lens 6. Therefore, the plural light beams are multiplexed extremely easily and respective elements need not be positioned with high precision; and the light sources are adhered directly, so the device is reduced in size.

Description

Detailed Description of the Invention (Field of the Invention) The present invention relates to an optical multiplexing device that combines a plurality of light beams respectively emitted from a plurality of laser light sources into a single light beam. The present invention relates to an optical multiplexing device that can perform synthesis easily and with high precision.

(Technical Background and Prior Art of the Invention) Conventionally, a means for generating a light beam has been used in light beam scanning devices such as various scanning recording devices and scanning reading devices that perform scanning by deflecting a light beam with an optical deflector. Various laser light sources are used as such. Among these laser light sources, semiconductor lasers in particular have many advantages, such as being smaller, cheaper, and consumes less power than gas lasers, etc., and can be directly modulated by changing the drive current. ing. However, on the other hand, when this semiconductor laser is used for continuous oscillation, the wavelength of the emitting laser is currently 780+V, and the output is small at most 20 to 30a+W. Therefore, optical beam scanning requires high-energy scanning light. It is extremely difficult to use it in devices such as scanning recording devices that record on recording materials with low sensitivity (metal films, amorphous DRAW materials, etc.), scanning recording devices that perform high-speed recording, and the like.

Also, some types of fluorophores are exposed to radiation (Xl, α-rays).

When irradiated with β rays, γ rays, electron beams, ultraviolet rays, etc., a part of this emitted rJ4Iil energy is accumulated in the phosphor.
It is known that when this phosphor is irradiated with excitation light such as visible light, the phosphor exhibits stimulated luminescence depending on the accumulated energy. , radiographic image information of a subject such as a human body is once recorded on a stimulable phosphor sheet having a layer made of a stimulable phosphor, and this stimulable phosphor sheet is scanned with excitation light such as a laser beam to make it shine. The resulting stimulated luminescent light is generated and photoelectrically read to obtain an image signal, and based on this image signal, the radiation image of the subject is recorded as a visible image on a recording material such as a photographic light-sensitive material, a CRT, etc. The applicant has already proposed a radiation image information recording and reproducing system that outputs radiation image information (Japanese Patent Application Laid-Open No. 55-1242).
No. 9, No. 55-116340, No. 55-163472
No. 56-11395, No. 56-104645, etc.).

In this system, a stimulable phosphor sheet on which radiographic image information is stored and recorded is scanned, the stimulable phosphor is stimulated to emit light, and excitation light with sufficient energy is applied to read the image information. It is necessary to irradiate the phosphor.

Therefore, in this radiation image information recording and reproducing system, it is extremely difficult to use a semiconductor laser or the like with a small optical output as described above as a light source for emitting excitation light.

Therefore, when obtaining a sufficiently high-energy scanning beam from a semiconductor laser with low optical output, or when further increasing the optical output even when using other laser light sources, it is recommended to use multiple laser light sources. It is conceivable to combine the light beams emitted from these laser light sources into one beam. In order to combine multiple light beams into one, an optical element such as a reflecting mirror is provided on each optical path of the light beams emitted from multiple laser light sources to change the optical path of each light beam, and A possible method is to provide various lenses on the optical path of the light beams and combine the light beams into one light beam having a desired beam diameter at a desired position. However, in the equipment that implements the above method, the optical system for combining the light beams becomes complicated, the overall size of the equipment increases, and the positional accuracy of mirrors, etc. is required to combine each light beam at a desired position. must be increased,
There is a problem that designing the optical system and adjusting each mirror etc. is difficult. In addition, even after highly accurate position adjustment, mirrors, etc. may become misaligned during use, so constant inspections and adjustments must be repeated, which may reduce the performance of the device. There was also the inconvenience that it took a lot of time and effort to maintain the system.

(Objective of the Invention) The present invention has been made in view of the above-mentioned problems, and provides an optical multiplexing device that combines light beams emitted from multiple laser light sources into a single light beam that is easy to design. It is an object of the present invention to provide an optical multiplexing device that allows adjustment of each element to be easily performed, is miniaturized, and hardly requires readjustment during use.

(Structure of the Invention) The optical multiplexing device of the present invention includes a surface waveguide plate having an optical waveguide layer provided on a substrate, and a grating lens provided on the surface waveguide plate, and includes a grating lens provided on the surface waveguide plate, and includes a grating lens provided on the surface waveguide plate. It is characterized by combining a plurality of light beams into a single light beam by utilizing the property of a grating lens that directs incident light to a single point in space. That is, a plurality of laser light sources are provided on the side surface of the surface waveguide plate so that their laser light emitting end surfaces are in contact with the optical waveguide layer, and the grating lens is used as the grating lens to emit light from the plurality of laser light sources and to transmit the light to the optical waveguide. By selecting a material that focuses the light beams incident on the layer to one point, it becomes possible to easily and efficiently combine the light beams. Note that the grating lens that focuses a light beam on a single point is a grating (with a pitch and orientation suitable for diffracting and focusing multiple light beams on a single point in space).
It may be a single grating lens having a grating (grating) or a plurality of grating lenses.

Incidentally, since the grating lens is already a known optical element (reference: Qen-ichi)
shi, Harua+i l”ujima,
and KenyaGoto: Wave ui
de ratin 1enses for o t
icaL Kasaogumi group (APPLIED 0PTIC8/
IJ une 1984/V 01.23. 11)
), the details of its properties, manufacturing method, etc. will be omitted here.

(Embodiments) Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing an outline of an optical multiplexing device according to a first embodiment of the present invention, and FIG. 2 is a plan view thereof.

The surface waveguide plate 4, which has three semiconductor lasers 1.2°3 fixed to its side surface, for example, is formed by coating a substrate 4A with an optical waveguide layer 4B made of a transparent material that transmits light. It is something. The semiconductor lasers 1.2.3 are arranged so that the emission end face for emitting a light beam is in contact with the optical waveguide layer 4B, and the light beams 1a, 2a, 3a is transmitted through the optical waveguide layer 4B as shown by the broken line in the figure. At a position on the optical waveguide 1i4B that is on the optical path of these light beams Ia, 2a, and 3a, the light beam that has passed through the optical waveguide layer 4B is diffracted to form a point PK in space outside the surface waveguide plate 4. A grating lens 5 is provided to focus the image. In the embodiment shown in FIGS. 1 and 2, the grating lens 5 is arranged so that the three light beams l
Three portions 5A are divided into three portions 5A, each of which is divided into the positions where the light beams a, 2a, and 3a are incident.

58.5G, each section having a grating with a different pitch and orientation. In other words, a grating lens having a grating with a certain pitch and orientation has a unique focal position depending on the incident angle of the light beam, the wavelength, the refractive index of the substrate, etc., so three lights whose incident directions are non-parallel to each other Beams 1a, 2a, 3a
In order to focus the light beams on the same point P, it is necessary to provide a grating lens portion having a grating suitable for focusing each light beam at a predetermined position. The respective light beams diffracted by the grating lens 5 are transmitted inside the surface waveguide plate 4 and are focused and synthesized at a point P1 outside the surface waveguide plate 4, and a collimator lens provided near the point P1 6 and becomes a parallel beam. In addition, in the above real ms, three light beams whose incident directions are non-parallel to each other are combined into one
Since the light beams are incident on two grating lenses 5 and combined into one light beam, the grating lens 5 has three portions 5A having gratings suitable for focusing the respective light beams at a point P1.

As shown in FIG. 3, for each of the three semiconductor lasers 1 and 2.3,
An independent grating lens 7.8.9 may be provided so that the light beams 1a, 2a, 3a are each diffracted by the grating lens 7.8.9 and focused at the same point in space.

As described above, in the device of the present invention, by using the grating lens provided on the surface waveguide plate, it is possible to extremely easily combine a plurality of light beams.
Even from a semiconductor laser with low optical output, a light beam with sufficient energy can be obtained and used widely as a scanning beam or the like.

In addition, the optical multiplexing device of the present invention is easy to design, and in order to efficiently combine light beams, only the alignment of each element and the selection of a grating lens having a desired grating during assembly are required. By the way,
There is no need for highly accurate positioning of each element, such as in optical multiplexing devices that use lenses, mirrors, etc.
Once the positions of the six elements are determined, there is almost no displacement over time, so maintenance management such as inspection and adjustment is almost unnecessary. Furthermore, in the device of the present invention, since the laser light source is directly attached to the surface waveguide plate on which the grating lens is provided, the entire device can be made smaller.

Next, another embodiment of the present invention will be described with reference to FIG.

As an example, three semiconductor lasers 11, 12, and 13 are mounted on the side surface of the surface waveguide plate 14 via collimator lenses 17, 18, and 19, respectively, with their light beam emission axes aligned in parallel. These semiconductor lasers 11.1
The light beams 11a, 12a, 13a emitted from 2.13 and transmitted through the surface waveguide plate 14 are parallel light beams because they have passed through collimator lenses 17, 18, and 19, respectively. The optical paths of the respective light beams are also parallel to each other. These light beams Ila
A grating lens 15 is provided at a position on the surface waveguide plate that is on the optical path of , 12a, 13a, but since all the light beams that enter this grating lens 15 are parallel lights that enter from a certain direction, All the light beams diffracted by the grating lens 15 leave the grating lens 15 at a focal length F
The light is focused and synthesized at a position If P 2 in space that is separated by the same amount. If all the light beams incident on the grating lens 15 are adjusted to become parallel lights in this way, it is possible to provide multiple grating lenses or to provide portions with different types of gratings within the same grating lens. There will be no need to do so.

Note that although the above explanation has been given using a semiconductor laser as an example of the laser light source, it goes without saying that something other than a semiconductor laser may be used as the laser light source, and the number of laser light sources can also be set arbitrarily. .

(Effects of the Invention) As explained above, according to the optical multiplexing device of the present invention, a plurality of laser light sources are provided on the side surface of the surface waveguide plate, and the light beams emitted from the laser light sources are directed onto the surface waveguide plate. By transmitting the light through the optical waveguide layer of the optical waveguide layer, transmitting it to the grating lens provided on the optical waveguide layer, diffracting it to the same point by the grating lens, and synthesizing it, the structure is simple and each element can be easily adjusted. It becomes possible to easily combine a plurality of light beams into one light beam. Therefore, by using the optical multiplexing device of the present invention, it becomes possible to easily create a high-power optical beam without relying on a complicated optical system. Further, according to the optical multiplexing device of the present invention, it is possible to downsize the entire device, and there is almost no need to inspect or readjust the position of each element, so its practical value is extremely great.゛

[Brief explanation of the drawing]

Figure 1 is the first fruit of the present invention! i! FIG. 2 is a plan view of the optical multiplexing device shown in FIG. 1; FIG. 3 is a plan view schematically showing the optical multiplexing device according to the second embodiment of the present invention. , FIG. 4 is a plan view showing an outline of an optical multiplexing device according to a third embodiment of the present invention. 1, 2.3.11.12.13... semiconductor laser 1
a, 2a, 3a, 11a, 12a, 13
a... Light beam 4... Surface waveguide plate 4A.
... Substrate 4B... Optical waveguide layer 5.7.8.9.15... Grating lens 6,
17.18.19...Collimator Lens Figure 1 Figure 2 Figure 3 Figure 4 (Voluntary) Procedure Name Book 1, Incident Indication Patent Application No. 1987-70499 2, Name of Invention Optical Multiplexing Device 3. Relationship with the case of the person making the amendment Patent Applicant Address: 210 NakaFB, Minamiashigara City, Kanagawa Prefecture Name: Fuji Photo Film Co., Ltd. 4 Agent: 7th Floor, Uraiya Building, 5-2-1 Roppongi, Minato-ku, Tokyo (7318) Patent Attorney Yanagi 1) Masashi (1 idiot) 5
, Date of amendment order None 6, Number of inventions increased by amendment None 7, Subject of amendment Drawing 8, Contents of amendment Figure 4 of the middle cylinder of the drawing will be amended as attached.

Claims (1)

[Claims] a surface waveguide plate having an optical waveguide layer provided on a substrate; a grating lens provided on the surface waveguide plate; 1. An optical multiplexing device comprising a plurality of laser light sources disposed in contact with each other, the grating lens focusing the light beams emitted from the plurality of laser light sources to one point.