JPS61231529A - Optical control type optical switch device - Google Patents

Abstract

PURPOSE:To increase the power of control light which is usable for a photoelectromotive voltage and to improve efficiency greatly by giving an elliptic distribution to the projection pattern of the control light from an optical fiber by using a spacer as a transparent body and a Fresnel lens then bending its optical path by using a prism. CONSTITUTION:A light source consists of the Fresnel lens 6 and prism 7 for bending the optical path across the spacer 5 made of the transparent body provided at an end part of the optical fiber 3, the light source system is fixed to an optical switch element 1, and the optical switch 1 and a photoelectromotive element 2 are connected by an electric wire 8. The control light 4 passed through the optical fiber 3 is diverged radially through then spacer 5, passed through the Fresnel lens 6, and then reflected totally by the right-angled prism 7 to have the optical axis bent at right angles; and the light is projected as control light 10 from a glass prism to irradiate the photoelectromotive element 2. The beam of the projected control light 10 is an elliptic Gaussian beam.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to the field of optical fiber communications and optical fiber applied measurement and control.

Prior Art FIG. 3 shows the prior art. In the figure, control light 14
is emitted from one end of the optical fiber 13, and the photovoltaic element 1
It was configured to irradiate 2.

11 is an optical switch element, and 12 is a photovoltaic element.

Problems to be Solved by the Invention In the conventional technology, the control light 1 from the optical fiber 13
The emission pattern of No. 4 has a concentric distribution with respect to the optical axis, and in order to effectively utilize the optical power of the control light 14, the photovoltaic element 12 was required to have an element surface that was nearly circular. However, in order to make the surface of the photovoltaic element 12 have a nearly circular structure, there are strict technical restrictions in terms of short-circuit current and open circuit voltage, and it is difficult to drive the optical switch element 11. Since a certain voltage is required, the surface shape of the photovoltaic element 12 is generally rectangular (rectangular).

In this case, in the conventional technique, there is a large mismatch between the surface shape of the photovoltaic element 12 and the intensity distribution of the emitted control light 14, and extra control light power is required. The present invention solves the problem of requiring extra optical power to illuminate a photovoltaic element with control light.

In addition, in FIG. 3, the optical fiber for control light and the surface of the optical switch element are not parallel, and there is a problem in that it is difficult to manufacture in terms of mounting and is difficult to miniaturize.

Means for Solving the Problems In order to solve the above-mentioned conventional problems, the present invention changes the output pattern of the control light from the optical fiber into an elliptical distribution using a transparent spacer and a Fresnel lens. I configured it like this. The present invention also provides a light-controlled optical switch device configured to bend an optical path using a prism.

Effect: With the above means, the control light emitted from the end of the optical fiber has an elliptical light intensity distribution after passing through the spacer and the Fresnel lens, which effectively activates the photovoltaic element having a rectangular (rectangular) surface. The unnecessary control light power is reduced. In addition, since the prism bends the optical path of the control light that has passed through the Fresnel lens, the optical fiber for control light can be made almost parallel to the surface of the optical switch element, improving manufacturing productivity and making it possible to downsize. It becomes.

Embodiment FIG. 1 is a perspective view showing an embodiment of the present invention, and FIG. 2 is a sectional view taken along the optical axis. FIG. 1 shows an example of an optically controlled optical switch consisting of a light source system in which control light 4 propagating through an optical fiber 3 irradiates a photovoltaic element 2 provided on an optical switch element 1. . The light source system is composed of a Fresnel lens 6 and a prism 7 for bending the optical path via a spacer 6 made of a transparent body provided at the end of the optical fiber 3.
is fixed to the optical switch 1 and the photovoltaic element 2.
and are connected by an electric wire 8.

The operation of the present invention will be specifically explained with reference to the cross-sectional view shown in FIG. In the figure, an optical fiber 3 with a core diameter of 80 μm is shown.
The control light 4 with a wavelength of 0.78 μm that has passed through it spreads radially through a spacer 5 made of a transparent glass material with a length of 3 m+, and extends approximately 3 fi and approximately 2 fi in the in-plane direction and in the vertical direction in the figure, respectively. After passing through a Fresnel lens 6 with a focal length of .6 mm, the passing light 9 is totally reflected by a right angle prism 7, bends the optical path at right angles, and then exits the glass prism 7 to become a control light 10, which generates a photovoltaic force. Irradiate element 2. The optical path length from the prism 7 to the photovoltaic element 2 is approximately 16 exposures in glass, and the emitted beam of control light 10 has a diameter of approximately 3 wa.
It was an elliptical Gaussian beam with a short axis of about 400 μm (in the in-plane direction) and a short axis of about 400 μm (in the vertical direction). The photovoltaic element 12 is composed of a GaAs solar cell in which 10 cells each having a width of 400 μm and a length of 250 μm are connected in series, and the area of the light receiving portion is 0.4×3 m. Approximately 60 inches of power could be used for photovoltaic power. Compared to the conventional structure, where only about 13 chips could be used at best, about four times the efficiency was achieved. In addition, in the present invention, the light source system is made almost parallel to the optical switch element, so it can be fixed with resin, improving manufacturing efficiency. The height of the entire structure is smaller than that of the conventional model, which is about the same as or slightly larger than the width and length of 10 mm, making it possible to convert it into a hut. The Fresnel lens 6 is an alumina thin film (refractive index: 1.
7) into the end of the glass spacer 6 by sputtering,
PMMA was made into a Fresnel lens shape mask by electron beam drawing, and then processed into a Fresnel lens by ion beam etching. Transparent epoxy resin was used to adhere each part.

In the embodiment of the present invention, an optical switch element using a PLZT thin film is used as an optical switch, but any other electrostatic type optical switch may be used. Further, the type of optical fiber 3 is not limited, nor is the material of the spacer and prism limited to glass, but any general optical material may be used as long as it is transparent. The material of the 7-Renel lens is not limited to alumina thin film; any transparent optical thin film or transparent optical material, whether inorganic or organic, can be used in combination with a refractive index that has a lens effect without any problems. . Further, although a GaAs solar cell array is shown as an example of a photovoltaic element, other photovoltaic elements may also be used.

Any device having a photovoltaic effect, such as a CdTe photovoltaic element, an a-3L solar cell, or a CdS/based solar cell, may be used.

Effects of the Invention By implementing the present invention, the power that can be used for the photovoltaic voltage of the control light, which was conventionally about 13 cm, has been reduced to about eso%, which is a dramatic increase in efficiency of about 4 times. In addition, in terms of mounting, the height dimension of the optically controlled optical switch element could not be made smaller than 40 tm due to the fixation of the control optical fiber, but by implementing the present invention, the height dimension of the optically controlled optical switch element can be made smaller than 40 tm without changing other dimensions. It has become possible to reduce the height to 20m and reduce the volume by about half.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment of the light-controlled optical switch of the present invention, FIG. 2 is a sectional view taken along the optical axis, and FIG. 3 is a perspective view of a conventional optical switch. 1... Optical switch element, 2... Photovoltaic element, 3... Optical fiber, 4, 9, 10...
...Control light, 6...Spacer, 6...
...Fresnel lens, 7...prism. Patent applicant: Director of the Agency of Industrial Science and Technology, etc., 3--97 Aino, 4-11 Betsugokou 5--S, 1-6-7, sequence reference 7--F'' Sosu A 8-11 electric light vk 13--1 optical fiber high 14-11 electric light, +4

Claims (1)

[Claims] an optical switch element that switches the optical path by applying a voltage between electrodes; a photovoltaic element that generates a photovoltaic voltage by irradiation with light and is electrically connected to the switch element; a light source that irradiates a power element with control light; the light source includes an optical fiber that propagates the control light; a transparent spacer that transmits the control light emitted from an end of the optical fiber; A light-controlled optical switch device comprising: a Fresnel lens provided at the other end of a spacer; and a prism that bends the optical path of the control light transmitted through the Fresnel lens and emitted.