PD300-IRG | Laser Photodiode Sensors | Power Sensors - Ophir



The PD300-IRG is a sensitive photodiode laser measurement sensor for telecom applications. It can accept either fiber input or free space with 5mm aperture. It has a removable filter. Without filter, its spectral range is 800 - 1700nm and its power measuring range is 10pW - 800µW. With filter the spectral range is 950 - 1700nm and the power range is 20µW - 150mW. The sensor comes with a 1.5 meter cable for connecting to a meter or PC interface.

PD300-IRG | Laser Photodiode Sensors | Power Sensors - Ophir
  • N.A.
  • Ø5mm (max)
  • 800-1700nm
  • 10pW-200mW
  • N.A.
  • Ø30 W x 29 D (mm)
  • 100μJ
  • 5W/cm²
  • 0.2 s
  • N.A.
  • N.A.
  • 200mW
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The total error when using a PD-300 head is listed as +/- 3%. Is that 3% of the reading or 3% of the total range?

It's +/-3% of the reading from full scale down to 5% of full scale. Below 5% of full scale one should switch to next range down for the best accurate linear results.


When using the fiber optic adaptor, how do we handle power loss due to the fiber relative to calibration?

All Ophir power meters, including photodiode power meters, have an air gap between the fiber tip and the sensor. Therefore they measure the power emitted by the fiber into the air and do not take into account any reflection losses there are in the fiber. Therefore, if in actual use, the fiber will be coupled with no loss to another element, then the losses should be added to the reading. These losses are usually about 4%. Thus if the reading on the Ophir meter is say 100mW, then in lossless use, the real power will be 104mW.


Can the PD300 be used with the filter in and with fiber adapter at the same time?

Yes, the adapter is arranged so the user can use it either with filter out or in.


When measuring a fiber output, should I put the fiber tip right up against the PD300 detector? If not, how close should I come?

The PD300 sensors are not designed to measure with the fiber pushed up right against the detector surface. It may be reading lower in such a case due to saturation of the detector from the concentrated beam or higher due to back reflections off the detector and back again from the fiber tip. The optimal reading will be where the beam is expanded to a size of 2-5mm diameter. Therefore, you should back off the fiber to a distance where the beam has expanded somewhat. Do not back off too far, otherwise if the nominal beam size is larger than given above, you may lose some of the beam off the edges of the detector.

FAQ: Photodiode Sensors for measuring very low laser powers FAQ: Photodiode Sensors for measuring very low laser powers
How to measure power of very low power pulsed laser beams How to measure power of very low power pulsed laser beams How to measure power of very low power pulsed laser beams

When using a photodiode laser power sensor to measure very low power pulsed beams (nW to mW), there are some issues you need to be aware of. This video shows you how to avoid some common problems and ensure maximum accuracy.

How do I measure laser power in telecom applications? How do I measure laser power in telecom applications? How do I measure laser power in telecom applications?

Optical measurements in telecom applications have unique challenges. This video will introduce you to the solutions Ophir offers to help you.

In this short “Basics” video, we review in general the use of photodiode sensors for measuring very low laser powers.

Tutorials and Articles

Laser Power Sensors introduction

As described in the general introduction, the thermopile sensor has a series of bimetallic junctions. A temperature difference between any two junctions causes a voltage to be formed between the two junctions. Since the junctions are in series and the «hot» junctions are always on the inner, hotter side, and the «cold» junctions are on the outer, cooler side, radial heat flow on the disc causes a voltage proportional to the power input. Laser power impinges on the center of the thermopile sensor disk (on the reverse side of the thermopile), flows radially and is cooled on the periphery. The array of thermocouples measures the temperature gradient, which is proportional to the incident or absorbed power. In principle, the reading is not dependent on the ambient temperature since only the temperature difference affects the voltage generated and the voltage difference depends only on the heat flow, not on the ambient temperature.


Common Reasons for Photodiode Sensor Damage or Out of Tolerance Conditions

We have included this document with your recent calibration order because we have noticed an out of tolerance condition obtained from your equipment when returned for calibration. This document was created to assist our valued customers in the proper care and maintenance of Ophir photodiode sensors. The following information is for reference only. If you have any reason to believe that the sensor is no longer performing within the original specifications, we always recommend that you send it in for repair and/or recalibration by our trained technicians to bring the unit back to the proper NIST traceable standards.

Ophir photodiode sensors can be used for many years without any repairs when used with the proper laser optical setup. Many of our customers have sensors that are using their original absorber that are over ten years of age. We hope that this document will enable you to also enjoy the long life and reliable results that Ophir- Spiricon is known for.


Effect of Ambient Conditions on Laser Measurements

We are often asked about the specified ranges of various ambient conditions (temperature, humidity, etc.) for Ophir instruments. In this article we will clarify the effects of these conditions on laser measurements, so you’ll be able to use your Ophir laser measurement instrument effectively.


Online Sensor Finder

The online sensor finder now gives comments to help the user find a solution in case he does not succeed in doing so. Examples below: Read more...


Customers that purchase the above items also consider the following items. Ophir-Spiricon meters and sensors include a standard manufacturers warranty for one year. Add a one year Extended Warranty to your meter or sensor, which includes one recalibration.