JPH04270301A - Optical connector - Google Patents

Abstract

PURPOSE:To allow the mutual utilization of light information between parallel optical paths in fields of optical computers, optical measurement, etc. CONSTITUTION:Many distributed refractive index rod lenses 2 are arranged at equal intervals by commonly disposing the optical axes 20 thereof to constitute a lens arranging body. Plural pieces of such lens arranging bodies are arranged in the direction orthogonal with the optical axes and a pair of prisms 3, 3 and the rod lenses 4 are interposed between the two arranging bodies to optically couple the two lens arranging bodies to each other.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a general-purpose optical system that can be used to construct optical systems in fields such as optical information processing, optical computing, optical conversion, optical interconnection, and optical measurement.

0002

[Prior Art] When constructing an optical system by combining lenses, gratings, prisms, etc., alignment adjustment of the optical axes of each component is extremely complicated, and many optical components or spatial modulation elements (hereinafter referred to as "SLM") are required. ), detector array, LED array, semiconductor laser array (hereinafter referred to as "
It is nearly impossible to align optoelectronic components such as LD arrays with high precision. Furthermore, since the mechanisms for aligning and fixing these parts are complicated, there are also problems in that it is difficult to miniaturize the optical system and to ensure reliability against temperature changes after assembly.

0003

[Problem to be solved by the invention] It is essential to solve the complexity and difficulty of assembly, alignment, and adjustment, the difficulty in miniaturizing the optical system, and the low reliability of conventional optical systems. This is the first object of the invention. In order to solve such conventional problems, the present inventors previously proposed patent application No. 2-253.
831 and Japanese Patent Application No. 2-253830, the following optical information transmission device and its manufacturing method were proposed.

That is, the device disclosed in the above-mentioned prior application arranges a large number of lenses on the same axis at equal intervals, forms conjugate image planes between each adjacent lens, and transmits light between the conjugate image planes. Although this method performs spatial transmission of a pattern, there is no mention of mutual optical transmission between coaxial lens arrays arranged in parallel in a direction orthogonal to the lens axis. However, in optical systems required for applications such as optical computers and optical measurement, optical information is often used mutually between parallel optical paths in which multiple optical systems are arranged in parallel (for example, in conferences, etc.). Rec
ord of 1990 International
Topical Meeting on Optic
al Computing, Paper No. 10B2,9
D17, 10Hz, etc.).

Accordingly, a second object of the present invention is to provide an optical system capable of mutual optical transmission between a plurality of parallel optical paths provided in parallel.

[0006]

[Means for Solving the Problems] An optical connection body in which two or more coaxial lens arrays each having a large number of lenses arranged at equal intervals on one optical axis are arranged substantially parallel to each other, the lens array A conjugate image forming surface having an equal magnification between adjacent lenses constituting the body, and optically connecting the plurality of lens arrays, and a conjugate image forming surface of any one of the lens arrays. The displayed light pattern information was transmitted to at least one conjugate imaging plane of another lens array.

In optically connecting the lens arrays described above, in a preferred embodiment, optical coupling is performed using two or more prism beam splitters and at least one lens.

Further, the lens used in the present invention is a gradient index rod lens having a rotationally symmetrical refractive index distribution that changes in the radial direction toward the outer circumference with the optical axis as the central axis, and has a flat end face. Therefore, it is suitable for easy connection and alignment with other parts.

[0009]

According to the present invention, for example, in the above-mentioned optical information transmission device, it is possible to mutually optically connect coaxial lens arrays arranged in parallel, and an optical system with a wide range of applications can be constructed. Furthermore, since a large number of conjugate image planes exist in parallel between each lens, when performing operations such as addition and subtraction between a plurality of images, each image can be easily arranged.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained in detail below based on embodiments shown in the drawings. FIG. 1 is a side cross-sectional view of an optical connector according to the present invention taken along a lens optical axis, and FIG. 2 is a plan cross-sectional view thereof.

Gradient index rod lenses (hereinafter simply referred to as rod lenses) 2 are arranged and fixed on a substrate 1 made of glass, ceramics, plastic, or the like. The rod lens 2 is a lens obtained, for example, by ion-exchanging cylindrical rod-shaped glass, and has a refraction that is rotationally symmetrical with respect to the central axis of the cylinder and decreases in the radial direction from the center toward the outer circumference with a substantially square distribution. This refractive index gradient causes light rays to be bent inward within the rod, acting as a convex lens. Such rod lenses 2 are arranged in multiple stages with a common optical axis 20.

If the length of each rod lens 2 is appropriately determined, a 1x (-1x) imaging system can be constructed by each rod lens. Note that, in many cases, it is convenient to form a pair of two rod lenses 2 to form a same-magnification (-1x) image as shown in the illustrated example.

In the present invention, each rod lens 2 constitutes a 1-magnification imaging system, and furthermore, the distance between each rod lens is set so that the conjugate imaging planes I1, I2, etc. of the rod lenses arranged in multiple stages are common. Adjust and fix. That is, coaxial 20
A 1-magnification imaging system is constructed in which the conjugate imaging surfaces of the rod lenses arranged above are all mutually common. I1-I in Figure 2
4 are all conjugate equal-magnification imaging planes.

In the present invention, a plurality of such coaxial lens arrays are arranged in parallel, and an optical signal propagating through one lens array is also transmitted to the other lens array. In the example of FIG. 2, two prisms 3 and one rod lens 4 interposed between them optically connect adjacent lens arrays.

When the two lens arrays are optically connected in this manner, a Mach-Zehnder interferometer as shown in FIG. 3 can be constructed, for example. In the apparatus of FIG.
A prism 31 in which two lens arrays are arranged in a quadrilateral pattern.
, 32, 33, 34 and rod lenses 41, 42 are optically connected. Of the prism group, prisms 31 and 34 located at the light incident position and the light output position are beam splitters, and the slopes of the remaining prisms 32 and 33 are simply reflective films.

In the apparatus shown in FIG. 3, by making the laser beam 10 incident on one of the lens arrays, for example, if the sample 5 is placed on the conjugate image plane I1, the optical thickness of the sample 5 is changed due to interference with the reference beam. Interference fringes corresponding to are obtained on the conjugate image plane I2.

[0017] Such a lens array can be manufactured using rod lenses as described above, and in this case, the shape of the groove gap between the lens end surfaces is made the same, and the conjugate image plane formation position within the groove is made the same. If the groove is manufactured in a constant manner, there is an advantage that insertion and alignment of the component can be easily performed by manufacturing the insertion portion of the component, such as an electronic circuit board, to be inserted into the groove so as to match the groove. In the example of FIG. 1, the spatial light modulator 6
This example shows a state in which the groove is made to fit the shape of the groove and is inserted along the groove wall while being in contact with the groove.

The aforementioned prisms 3, 31, 32, 33, 3
4 also uses a refractive index matching liquid, etc., and inserts the outer surface along the inner wall of the groove while making contact with it, making it easy to align optical systems such as interferometric optical meters, which are generally extremely difficult to align. Can be fixed. Furthermore, when inserting the sample 5 in the apparatus shown in Fig. 3 or inserting the detector array into the I2 position for detecting interference fringes, the relative position between the conjugate imaging plane and the inner wall of the interlens groove must be made constant. Therefore, parts can be easily inserted and positioned in accordance with the shape of the grooves between the lenses of the lens array.

[0019]

[Effects of the Invention] According to the present invention, it is possible to easily insert and position optical components, which was extremely difficult in the past, and optical connections between multiple lens arrays can be used in various fields such as optical computing and optical measurement. More complex and practical optical systems can be easily assembled.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing an embodiment of the present invention;

FIG. 2 is a cross-sectional plan view of the device in FIG. 1;

FIG. 3 is a plan sectional view showing another embodiment of the present invention.

[Explanation of symbols]

1 substrate, 2, 4, 41, 42 gradient index rod lens,
3 prism, 5 sample, 6 spatial light modulation element, 10 laser beam, 20 lens optical axis, 31, 34 prism beam splitter, 32,
33 Prism mirror.

Claims (3)

[Claims] 1. An optical connection body in which at least two or more coaxial lens arrays each having a plurality of lenses arranged at regular intervals on one optical axis are arranged substantially parallel to each other, the lens array has a conjugate imaging plane with equal magnification between adjacent lenses constituting the lens array, and optically connects the plurality of lens arrays, and has a conjugate imaging plane in any one of the lens arrays. An optical connector configured to transmit displayed optical pattern information to at least one conjugate imaging plane in another lens array. 2. The optical connector according to claim 1, wherein the optical connection between the plurality of lens arrays is composed of two or more prism beam splitters and at least one lens. 3. The lens array according to claim 1 or 2, wherein each lens constituting the lens array is a rod lens having a rotationally symmetrical refractive index distribution that changes in a radial direction toward the outer circumference with the optical axis as the center. The optical connector described.