Fiber Optic Power Meters with Internal Sensor

PM60 and PM61 Series Features
Item #	PM60 Series	PM61 Series
Rechargeable Battery
Fast Charging vis USB-C Connector
Embedded Wireless Charging Coil	-
Data Storage to Internal Flash Memory
Internal Flash Memory Access via USB
Pass / Fail Analysis	-
Admin / User Levels	-
Physical Menu Button Configuration	-
Visual Fault Locator (VFL)	-
USB 2.0 Full Speed Interface
Bluetooth Low Energy Connectivity	-
OPM Software Compatible

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Figure 1.1  A PM61CH power meter with a fiber-optic patch cable (sold separately) attached to the detector port is shown here.

Fiber Optic Power Meter Features

• Si (PM6xA) or InGaAs (PM6xC or PM6xCH) Sensors
• Wavelength Range:
• 400 nm - 1100 nm (Si)
• 800 nm - 1700 nm (InGaAs)
• Power Ranges:
• -65 dBm to 16 dBm (300 pW - 40 mW) for PM6xA
• -70 dBm to 13 dBm (100 pW - 20 mW) for PM6xC
• -55 dBm to 23 dBm (3 nW - 200 mW) for PM6xCH
• Interchangeable Fiber Connectors:
  • PM20-25 2.5 mm Ferrule Adapter Included
  • FC/PC, FC/APC, SC, ST^®, LC, or SMA Adapters Sold Separately Below
• Absolute and Relative Measurements Displayed in dBm, dB, pW, nW, µW, mW, and W
• NIST- and PTB-Traceable Wavelength Calibration
• Digital Menu Navigation via Physical Buttons and Capacitive Touchscreen
• Support for Remote Operation
  • Optical Power Meter PC Software Available (See Software Tab for Details)
  • Applications for Android™ or iOS^® for Wireless Operation from a Mobile Device (Not Included)

The PM60 and PM61 Series of Fiber Optic Power Meters are robust, full-featured, handheld instruments, which together cover the full range of optical fiber applications within the 400 - 1700 nm range with optical powers ranging from -70 dBm to +23 dBm (100 pW - 200 mW). A rugged enclosure, internal sensors, kickstand, and hand strap eyelet (hand strap not included) make these models ideal for field or lab applications. The PM60A and PM61A power meters use a Si sensor for detection between 400 nm and 1100 nm, while the PM60C, PM60CH, PM61C, and PM61CH use an InGaAs sensor for detection between 800 nm to 1700 nm. 

Each unit is shipped with a PM60 or PM61 series power meter with an attached PM20-25 fiber adapter, USB cable (Type A to Type C), Certificate of Calibration, and Quick Reference.

Device Design
The PM60 and PM61 series power meters can be operated using both a 2.8" capacitive touchscreen and the physical keys shown in Figure 1.1. An interactive GUI is available to demo all the features (click here or see the Interactive Demo tab). Each power meter comes with a USB C rechargeable, lithium polymer (LiPo) battery with a 2300 mAh capacity. The PM61 series power meters feature an additional wireless charging capability via an inductive charging coil. Each power meter is shipped with an SM05 (0.535"-40) internally threaded PM20-25 adapter for fiber patch cables with 2.5 mm ferrules. The PM20-25 adapter is designed without a locking mechanism to allow for fast and efficient power measurements using patch cables with a variety of terminations.

The PM61 series power meters are equipped with a Visual Fault Locator (VFL) consisting of a 650 nm class 2 guide laser and 2.5 mm ferrule receptacle which can be used to find fibers in a bundle, breaks in a fiber, or alignment into an optical fiber. The VFL can be used in a continuous wave (CW), 1 Hz flashing, or 3 Hz flashing setting.

Remote Operation
The PM60 and PM61 series power meters can be controlled remotely using Thorlabs' Optical Power Monitor (OPM) software. Both series feature a USB 2.0 interface to connect to a PC. Additionally, the PM61 series has a built in Bluetooth module that allows the user to establish a wireless connection to a PC. Remote connectivity allows the user to access the power meter settings, visualize power measurements, and record data directly through the OPM software. Please see the Software tab for details.

Analysis Tools
The Fiber Power Meter Series offer Data Logging and Statistics analysis tools which allow for power levels over a specified time period to be recorded and saved on the internal memory to be accessed at a later time using the USB connection and an external PC. The Data Logging tool shows a time trace of the power levels over the given interval while the Statistics tool shows the number of samples, elapsed time and mean, maximum, and minimum power levels. The PM61 series also features the Pass / Fail Analysis tool which gives a visual indication to whether a given measurement is within a predefined power range. 

*ST^® is a registered trademark of Lucent Technologies, Inc.

Interactive Demo

An interactive GUI is available in this tab to demo all the features of the PM60 and PM61 Series Power Meters. A full-screen demo is also available by clicking the Full-Screen PM60 / PM61 Demo button. For computers with a touchscreen, the demo supports all swipe gestures to switch screens. Otherwise, a mouse or directional and enter keys can be used to interact with these functions. The GUI provides the opportunity to browse all submenus and change settings. For information on navigating the measurement and menu screens, please see the PM60 and PM61 Series Power Meter manual.

The demo offers access to all the features of the PM60 or PM61 Series Power Meters that are selectable while using either the touchscreen or the physical keypad with limited configurability. The simulated measured power level can be set over several decades and simulated measurements can be performed displaying as it would on the physical device.

Pulsed Laser Emission: Power and Energy Calculations

Click above to download the full report.

Determining whether emission from a pulsed laser is compatible with a device or application can require referencing parameters that are not supplied by the laser's manufacturer. When this is the case, the necessary parameters can typically be calculated from the available information. Calculating peak pulse power, average power, pulse energy, and related parameters can be necessary to achieve desired outcomes including:

• Protecting biological samples from harm.
• Measuring the pulsed laser emission without damaging photodetectors and other sensors.
• Exciting fluorescence and non-linear effects in materials.

Pulsed laser radiation parameters are illustrated in Figure 170A and described in Table 170B. For quick reference, a list of equations is provided below. The document available for download provides this information, as well as an introduction to pulsed laser emission, an overview of relationships among the different parameters, and guidance for applying the calculations. 

Equations:
Period and repetition rate are reciprocal:			and
Pulse energy calculated from average power:
Average power calculated from pulse energy:
Peak pulse power estimated from pulse energy:
Peak power and average power calculated from each other:
		and
Peak power calculated from average power and duty cycle*:
		*Duty cycle () is the fraction of time during which there is laser pulse emission.

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Figure 170A  Parameters used to describe pulsed laser emission are indicated in this plot and described in Table 170B. Pulse energy (E) is the shaded area under the pulse curve. Pulse energy is, equivalently, the area of the diagonally hashed region. 

Table 170B  Pulse Parameters
Parameter	Symbol	Units	Description
Pulse Energy	E	Joules [J]		A measure of one pulse's total emission, which is the only light emitted by the laser over the entire period. The pulse energy equals the shaded area, which is equivalent to the area covered by diagonal hash marks.
Period	Δt	Seconds [s]		The amount of time between the start of one pulse and the start of the next.
Average Power	Pavg	Watts [W]		The height on the optical power axis, if the energy emitted by the pulse were uniformly spread over the entire period.
Instantaneous Power	P	Watts [W]		The optical power at a single, specific point in time.
Peak Power	Ppeak	Watts [W]		The maximum instantaneous optical power output by the laser.
Pulse Width		Seconds [s]		A measure of the time between the beginning and end of the pulse, typically based on the full width half maximum (FWHM) of the pulse shape. Also called pulse duration.
Repetition Rate	frep	Hertz [Hz]		The frequency with which pulses are emitted. Equal to the reciprocal of the period.