Optical Fiber Sensor
Optical Fiber Sensor
Optical fiber sensor created by the fusion of Shinkosha’s crystal
and optical technology helps disaster prevention and mitigation by utilizing information technology.

OTDR-optical fiber sensor disaster prevention system


  • Since sensor does not use electricity and data transmitter is unnecessary, high reliability without data loss due to failure is realized.
  • Already used on site in electricity, harbors and river management.
  • Information from scattered sensors is collectively measured almost in real time (once every 5 second).
  • Optical fiber sensors can be used in adverse environments such as mountains, coasts, and sewers.


Faraday sensor series (single core, single mode fiber)

A series of optical fiber sensors that detect “magnetic field” by Faraday effect. We have the following products required for disaster prevention systems by optimizing the configuration of sensors and magnets.

Please contact sensor@shinkosha.com for catalog request.

Proximity sensor

When a magnetic field of 1000 gauss or more is applied to the sensor, the incident light to the sensor returns as reflected light through the same optical fiber. However, when no magnetic field is applied to the sensor, the incident light to the sensor does not return to the optical fiber. It operates as a simple optical fiber proximity sensor if you use a permanent magnet to apply a magnetic field.
<Application examples>

  • Open / close detection of sluiceway and sluice pipe
  • Open / close detection of tide gate
  • Open / close detection in explosion-proof area
  • Open / close detection in noisy environment such as electric power facilities

<Related products>
We have small type (φ6 × 20L / without waterproof structure) and sensor & magnet integrated type. Also there is a type in which a magnet is built into the sensor case and the target is a magnetic plate (e.g. SUS430).


Float type liquid level sensor

This is a liquid level sensor using a float with a built-in magnet. The structure of the float has been sufficiently examined so that it can be used outdoors, such as in rivers.
<Application examples>

  • Monitoring of warning and dangerous water levels in rivers
  • Wide area monitoring of flood in urban areas such as underground malls and subways
  • Completion and verification of flood hazard map
  • Detection of road flood

Tipping bucket rain gauge

This tipping bucket rain gauge has an optical fiber proximity sensor instead of a reed switch. The number of tipping movement of the bucket is measured as the number of state transitions of the reflected light. Since no electrical components are used in the rain gauge and the monitoring line is made up of components used for optical communication, a highly reliable system can be easily constructed.
<Application examples>
Via an optical coupler, the rain gauge can be connected to an optical fiber with other sensors such as warning water level sensor and debris flow sensor. This makes it easy to build a comprehensive disaster monitoring system that integrates different information such as “rainfall & warning water level” and “rainfall & debris flow”.

Tilt sensor (prototype)

Activated when a vertically fixed sensor is tilted above the threshold. (In normal conditions, incident light returns on the same optical fiber as reflected light, but when the sensor is tilted, the reflected light disappears.)
<Application examples>

  • Slope collapse detection
  • Fence tilt detection due to falling rocks

Flow direction sensor (prototype)

This sensor is attached to the sluiceway at the point where the tributary joins the main stream, and detects the backflow of the tributary to notify the gate operation timing. The sensor detects the direction of water flow with a blade and changes the level of the reflected light by forward and backward flow.
Please contact sensor@shinkosha.com

Business content related to optical fiber sensors

Item Content
Optical fiber sensor For design / manufacturing / sales Products other than described above and prototypes, please contact us at the following.
OTDR (Optical Time Domain Reflectmeter) Using commercialized OTDR from domestic and foreign manufacturers for monitoring optical fiber lines. (Since an off-the-shelf OTDR is used as a sensor detector, it is possible to construct a system with reduced costs.)
We can introduce the product according to customer’s request.
Monitoring software Standard software for system review is available. Also important points in your own software development will be supported. Furthermore, we can introduce proven system integrators upon request.
System construction Construction of a disaster prevention system is not included in our business, but we will provide support for customers, including tests on redundant design and track design.
Installation work Installation work is not included in our business, but the designing of sensor mounting jig is available upon request. Please contact us at the following.
Small-scale system (Stand-alone type) Please contact sensor@shinkosha.com

Please contact sensor@shinkosha.com for inquiries about our optical fiber sensors.