Working principle the optical power meter


The optical power meter is used to measure absolute optical power or relative loss of optical power through a section of optical fiber

In fiber optic systems, measuring optical power is fundamental, much like a multi-meter in electronics;

In optical fiber measurement, the optical power meter is a common table of heavy load.

By measuring the absolute power of a transmitter terminal or optical network, an optical power meter can evaluate the performance of optical terminal equipment.

The combination of optical power meter and stable light source can measure the loss of optical fiber connection, check the continuity and effectively help to evaluate the transmission quality of optical fiber link.

Working principle

The basic structure of optical power meter contains the host and the probe, the basic principle of optical power meter figure as shown in the figure below, when the metering exposure to produce the corresponding photocurrent, namely on the optical detector host part of the role is to detect the signal amplification and D/A transformation into the CPU and the CPU processing digital signal in optical power or power level of the corresponding form display.

Basic diagram
Basic diagram△

The function:

A measuring instrument that directly expresses the intensity of the received light in terms of power, and is used to measure the intensity of light, such as the power output of optical fiber transmission and the laser size emitted by laser generator.

The production standard of the product is 500mw output laser power, which can be measured by optical power meter if the product meets the requirements。

The optical power meter is a kind of instrument to test the strength of laser signal in optical cable, it is generally used with laser light source, or can be used alone (one end of the light terminal machine).

Optical power is essential for the manufacture, installation, operation, and maintenance of an optical transmission system.

In the field of optical fiber, no engineering, laboratory, production shop or telephone maintenance facility can work without an optical power meter.

Orientek TPM-35 power meter

For example, the optical power meter can be used to measure the output power of the laser light source and LED light source;

Used to confirm the loss estimation of optical fiber links;

The most important is that it is the key instrument to test the performance index of optical components (optical fiber, connector, attenuator, etc.).

Model of the optical power meter

Orientek now have 4 types of power meter: T22M、T25m、TPM35、KPN-35。


Pocket mini design, compact and light, easy to operate;

2.5mm universal interface design, which can meet FC, SC, ST, and LC(optional) interfaces;

It has a high accuracy of ± 0.2db and can be calibrated with six wavelengths.

100 hours of ultra-long standby, long endurance, its wavelength range up to 800-1700nm;

The effective service life of the rubber dust cap can reach tens of thousands of times, fully and effectively protecting the laser


The appearance and functions are similar to those of the T22M. The difference lies in the simple bracket design of the T25m, which is convenient to operate.

Split-type anti-falling silicone sleeve can effectively protect the machine;

Plug and play, fast response, generally used with the stable source T15m.

Orientek T25m power meter & T15m light source
Orientek T25m power meter & T15m light source△


Compared with the previous two models, the size is slightly larger. The standard SC adaptor interface is equipped with ±0.2db high precision measurement, 6 kinds of memory wavelengths can be calibrated, and the backlight LED large screen display can adapt to special conditions. Its 200 hours of ultra-long standby, effectively improve work efficiency; Waterproof button with a key to start automatic shutdown function, do not worry about accidental loss; Simple bracket design, can choose their own way of placement; Rubber dust cap, rubber sheath, effectively protect the fuselage, dust, and fall.

Normally, the auspicious kpm-35 optical power meter is used in combination with theTLS-35.

Orientek TPM-35power meter& TLS-35 light source
Orientek TPM-35power meter& TLS-35 light source△


KPN-35, PON power meter,The main measurement is 1310nm burst signal.

The shape is light and easy to carry; It sets the threshold value of instrument test through the management software, and can provide ten groups of threshold value choices, with the mode of pass, warning and failure; USB can be connected to the computer, with large capacity data storage; LED automatic backlight setting, automatic shutdown can be quickly canceled, simple bracket design and split anti-fall silicone cover protection, to meet the user's maximum demand.


1)Turn on the machine;

2)Press“λ”key to adjust the wavelength;(Ps:Manual zero setting is required (some instruments have automatic zero setting). Note that zero setting is required after each shift;)

3)Access the light signal to be measured;

4)The screen displays the current measured value (dBm), and the corresponding value of power can be displayed by pressing the "dB" key;

5)In order to avoid the error caused by receiving port connection, the average value can be obtained by repeated measurement several times。


1)the wavelength of power meter and tested optical signal should be same;

2)If the optic to be measured is output by the movable connector, clean the end surface of the movable connector and connect it with the optical power meter; If it is bare fiber, the corresponding bare fiber adaptor interface shall be used;

3)The interface of power meter must be well connected and accurately positioned, otherwise the measurement result error is large;

4)Pay attention to keep the laser clean, after use or long time unused should be covered with dust cap;

5)The instrument should avoid strong mechanical vibration, collision and drop during use/transportation.