OTG-M420 Fiber Optic Temperature Sensor

High accuracy SCBG-based fiber optic temperature sensor for tip measurement applications.

Opsens Solutions’ OTG-M420 fiber optic temperature sensor offers the highest performances in the industry. The OTG-M420 sensor uses the well proven technique based on the temperature-dependent bandgap of GaAs crystal as the temperature transduction mechanism. Its small sensing GaAs crystal located at the tip of the optical fiber makes it convenient for tip measurement applications.

Combined with Opsens Solutions’ SCBG (Semiconductor Bandgap) signal conditioning technology and with the inherent advantages of fiber optic, the OTG-M420 delivers unprecedented repeatability and reliability in the most adverse conditions such as high level of EM, RF, MR and microwave field environments.

The OTG-M420 is made with industry standard optical fiber and is compatible with all Opsens Solutions’ SCBG signal conditioners. This compact and robust fiber optic temperature sensor is available with different optical cables and sheath options and is customizable according to customer specific applications or for OEM-type applications.


  • Small and robust design
  • Outstanding repeatability
  • EMI/RFI and microwave immune
  • Intrinsically safe
  • OEM-type and custom version


  • Surface and core temperature monitoring in EMI environments
  • RF, ultrasound environments
  • Temperature monitoring for industrial applications
Temperature operating range

-40 °C to +250 °C (Other ranges available upon request)


0.01 °C


± 0.8 °C or better for other temperature range

Response time

220 ms or better

Operating humidity range

0-100 %

MRI/EMI/RFI susceptibility

Complete immunity


NIST traceable

Cable length

1.5 meters standard (Other lengths available)

Optical connector

LCA, ST standard

Sensor diameter

0.420 mm O.D.

Cable sheathing

PVC tight buffer ( ≤ 85 °C) or Teflon™ ( ≥ 85 °C)

Signal conditioner compatibility

All Opsens Solutions’ SCBG signal conditioners

Opsens Solutions Inc. reserves the right to make any changes to the above specifications without prior notice.

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