JPS6398568A - Optical potential device - Google Patents

Abstract

PURPOSE:To stably measure voltage with high accuracy even under environment largely changing in vibration or temp., by providing an aperture part having a diameter large than that of transmission light to each of the spacers interposed between optical elements along an optical axis. CONSTITUTION:An optical apparatus is constituted by arranging a collimator 2 adjusted so that the focus thereof is matched with P-points at the incident and emitting ends of an optical fiber by incorporating a lens in a receptacle, a polarizer 3, a 1/4 wavelength plate 4, an electro-optical effect element 5, a detector 6, a angled prism 7 and collimators 2', 2'' in this order. Spacers 9 each having a coefficient of thermal expansion almost the same to that of the adjacent optical element and having a hole larger than the diameter of light aligned along the optical axis (a) are interposed between the respective optical elements. Further, an auxiliary prism 8 having a recessed part on the surface thereof is fixed to the prism 7 outside the total reflection surface of a light path and a structure wherein these optical element and spacers 9 are all united is fixed to a housing case 1 through an elastomer 11.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an optical transformation device, and particularly relates to an optical transformation device.

The present invention relates to an optical conversion device suitable for highly accurate and stable voltage measurement even in environments with large temperature changes.

[Conventional technology]

As described in Japanese Unexamined Patent Publication No. 61-10776, the conventional device uses a polarizer, a
All-system elements such as a 1/4 wavelength plate, an electro-optic effect element (for example, BGO or BSO), and an analyzer are sequentially arranged in a straight line. A voltage sensor using such light is
It is characterized by its small size and ability to faithfully reproduce transient voltage waveforms.

When used as a power transformer in applications that require high reliability, it is essential that it has sufficient measurement accuracy to withstand vibrations that occur under various conditions and harsh environments such as temperature changes. It is. Therefore, when implementing an optical sensor, it is necessary to take measures such as holding the optical voltage sensor with a cushioning material and storing it in a case, but if external vibrations are applied or the temperature changes, the optical voltage will increase. Conventionally, no consideration has been given to the problem that relative displacement occurs between the sensor and the case that houses it, which interferes with optical transmission.

[Problem that the invention seeks to solve]

The above-mentioned conventional technology does not take into consideration vibrations on the optical voltage sensor, a reduction in the holding function due to changes in the buffer material, and the effects of heat, and these changes in the external environment increase errors in voltage measurement. There was a problem with poor accuracy.

An object of the present invention is to provide a highly accurate optical conversion device in which no stress is applied to the optical voltage sensor even if the external environment changes, and there is no deviation of the optical axis due to relative displacement between the storage case and the optical sensor. There is a particular thing.

[Means for solving problems]

The above object is to interpose a spacer having an opening between each of the optical system elements constituting the optical voltage sensor so that the planes of polarization along the optical axis are not in contact with each other, and to connect each of the optical elements and the spacer. This is accomplished by gluing, fixing, and integrating.

[Effect]

The spacer is selected to have a coefficient of thermal expansion close to that of each optical system element. At this time, by providing an opening in the spacer along the optical axis (optical path) that is larger than the diameter of the transmitted light, there is a gap (airtight) at the interface between each optical system element.
The effects of interface stress due to thermal effects, etc. are alleviated,
It does not interfere with the plane of polarization in optical transmission.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

The optical device 1 shown in the figure includes a collimator 2.0 that has a lens built into a receptacle and is adjusted to focus on a point P at the input and output ends of an optical fiber. Polarizer 3. 1/4 wavelength plate 4.
Electro-optic effect elements such as BGO & BSO5. Analyzer6.
Right angle prism 7, auxiliary prism 8. Collimator 2', 2
The optical system elements have the same coefficient of thermal expansion as the adjacent optical system elements, and the optical axis a
A spacer 9 having a hole larger than the optical diameter is interposed along the optical axis, and the interface where the optical system element and the spacer 9 are fused is point-bonded by UV-ultraviolet bonding or the like. prism 7
An auxiliary prism 8 having a concave portion on its surface is fixed to the outside of the total reflection surface of the optical path. These optical system elements and spacers are integrated into a storage case 10 through an elastic body 11.
Fixed to.

According to this embodiment, the optical voltage sensor has a non-contact state at the boundary surfaces of each optical system element in the portion through which light passes, so that the boundary surfaces are not subjected to physical distortion due to heat or the like. The plane of polarization remains unchanged. Furthermore, since it is airtight and is not exposed directly to the atmosphere, there is no need to worry about atmospheric dust or condensation. Therefore, stable and highly accurate voltage measurement is possible even if there are changes in the external environment such as external vibrations or temperature changes.

Although the present invention has been described with respect to a photovoltage sensor, similar effects can be obtained when applied to a photocurrent sensor having a similar optical system.

〔Effect of the invention〕

According to the present invention, it is possible to prevent the occurrence of distortion in the portion of each optical system element of a photovoltage sensor through which light passes and the incorporation of external impurities, and to achieve stable and variable-accuracy photovoltage measurement. effective.

[Brief explanation of the drawing]

The figure is a 4'* diagram showing one embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Photovoltage measuring device, 2.2', 2'... Collimator, 3... Polarizer, 4... 174 wavelength plate, 5...
... Electro-optical element, 6... Analyzer, 7... Right angle prism, 8... Auxiliary prism, 9... Spacer, 10
...Storage case. 11...Elastic body.

Claims (1)

[Claims] 1. Optical method conversion characterized in that an optical device consisting of a polarizer, an electro-optic effect element, and an analyzer is arranged in a storage case, and a spacer having an opening is interposed between each optical system element of the optical device. Device.