Fiber-Coupled Laser Sources: Visible

SM, MM, and PM Sources Available
Full Output Powers from 2.5 to 50 mW
Stable, Low Noise, Constant Power Operation

S1FC660

660 nm, 15 mW

Front Panel Display Provides an Enable Button, Laser Power Control, and Display Screen

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Overview
Specs
Pin Diagrams
Laser Safety
Feedback

Single Channel Benchtop Laser Sources Selection Guide
Spectrum	Wavelength	TEC	Laser Type	Cavity Type	Output Fiber Type
Visible	405 - 675 nm	No	Semiconductor	Fabry Perot	SM, MM, or PM
Visible	405 - 685 nm	Yes	Semiconductor	Fabry Perot	SM
NIR	785 - 1550 nm	No	Semiconductor	Fabry Perot	SM or PM
	705 - 2000 nm	Yes	Semiconductor	Fabry Perot	SM
	1310 - 1550 nm	Yes	Semiconductor	DFB	SM
	1900 - 2000 nm	N/A	Fiber Laser	Fabry Perot	SM
MIR	2.7 µm	N/A	Fiber Laser	Fabry Perot	SM
Other Fiber-Coupled Laser Sources

Features

Available Wavelengths:
- SM: 405 to 675 nm
- MM: 473 nm
- PM: 635 nm
Single Mode or Multimode FC/PC Fiber Interface
Power Level is Adjustable via Knob and BNC Modulation Input
Stable, Low Noise, Constant Power Operation
Interlock Circuit Provided via 2.5 mm Mono Jack

Thorlabs offers single mode, multimode, and polarization-maintaining fiber-coupled laser sources in the visible spectrum. Each benchtop laser source features both a pigtailed Fabry-Perot laser diode and current controller in a single unit.

The front panel of each laser source displays the output power in mW, an on/off key, and an enable button, and a knob to adjust the laser power. The back panel includes a BNC input that allows the laser diode drive current to be controlled via an external DC or sine wave voltage source and a remote interlock input.

Please refer to the table to the right for all of our single channel benchtop laser sources.

Key Specifications^a
Item #	S1FC405	S1FC635	S1FC637	S1FC660	S1FC675	S1FC473MM	S1FC635PM
Fiber Type	SM					MM	PM
Wavelength	405 nm	635 nm	637 nm	660 nm	675 nm	473 nm	635 nm
Spectrum						-	-
Full Output Power	8.0 mW (Min)	2.5 mW (Min)	8.0 mW (Min)	15.0 mW (Min)	2.5 mW (Min)	50 mW (Max)	2.5 mW (Min)
Power Stability	15 min: ±0.05 dB, 24 hr: ±0.1 dB (After 1 hr Warm-up at 25 ± 10 °C Ambient)

Complete specifications are available in the Specs tab above.

Click to Enlarge
S1FC473MM Shown with M43L01
Multimode Patch Cable

Single Mode Source Specifications
Item #		S1FC405	S1FC635	S1FC637	S1FC660	S1FC675
Wavelength	Minimum	395 nm	625 nm	630 nm	645 nm	660 nm
	Typical	405 nm	635 nm	637 nm	660 nm	675 nm
	Maximum	415 nm	640 nm	645 nm	665 nm	680 nm
Spectrum^a
Minimum Full Output Power		8.0 mW	2.5 mW	8.0 mW	15.0 mW	2.5 mW
Setpoint Resolution		0.01 mW	0.01 mW	0.01 mW	0.01 mW	0.01 mW
Laser Class		3B	3R	3B	3B	3R
Fiber
Fiber Type		S405-XP	SM600	SM600	SM600	SM600
Mode Field Diameter^b		3.3 µm @ 405 nm	3.6 - 5.3 µm	3.6 - 5.3 µm	3.6 - 5.3 µm	3.6 - 5.3 µm
Numerical Aperture		0.12	0.10 - 0.14	0.10 - 0.14	0.10 - 0.14	0.10 - 0.14
Output Fiber Connector		FC/PC, Wide 2.1 mm Key Compatible
Electrical
Power Stability	15 min: ±0.05 dB, 24 hr: ±0.1 dB (After 1 hr Warm-up at 25 ± 10 °C Ambient)
Display Accuracy	±10%
Adjustment Range	~0 mW to Full Power
Input Power	115 VAC / 230 VAC (Switch Selectable) 50 - 60 Hz
Modulation Input	0 - 5 V = 0 - Full Power, DC or Sine Wave Input Only
Modulation Bandwidth	5 kHz Full Depth of Modulation 30 kHz Small Signal Modulation
Environmental
Operating Temperature	15 to 35 °C
Storage Temperature	0 to 50 °C

Spectral plots are typical, and actual spectra vary from lot to lot. For further information, please contact Tech Support.
Mode Field Diameter (MFD) is specified as a nominal value.

Multimode Source Specifications
Item #	S1FC473MM
Wavelength	473 nm
Max Output Power^a	50 mW
Stability	15 min: ±0.05 dB, 24 hr: ±0.1 dB (After 1 hr Warm-Up at 25 ± 10 °C Ambient)
Display Accuracy	±10 %
Setpoint Resolution	0.1 mW
Adjustment Range	~0 mW to Full Power
AC Input	115 / 230 VAC (Switch Selectable) 50 - 60 Hz
Modulation Input	0 - 5 V = 0 - Full Power, DC or Sine Wave Input Only
Modulation Bandwidth	5 kHz Full Depth of Modulation 30 kHz Small Signal Modulation
Fiber	FG105UCA
Environmental
Operating Temperature	15 to 35 °C
Storage Temperature	0 to 50 °C

Output power ranges from 0 - 50 mW. Due to variations between laser diodes, maximum output power may be higher.

Polarization-Maintaining Source Specifications
Item #	S1FC635PM
Wavelength^a	635 nm
Min Full Output Power	2.5 mW
Extinction Ratio^a	>20 dB
Stability	15 min: ±0.05 dB, 24 hr:±0.1 dB (After 1 hr Warm-up at 25 ± 10 °C Ambient)
Display Accuracy	±10%
Setpoint Resolution	0.01 mW
AdjustmentRange	~0 mW to Full Power
Environmental
Operating Temperature	15 to 35 °C
Storage Temperature	0 to 50 °C
AC Input	115 VAC / 230 VAC (Switch Selectable) 50 - 60 Hz
Modulation Input	0 - 5 V = 0 - Full Power, DC or Sine Wave Input Only
Modulation Bandwidth	5 kHz Full Depth of Modulation 30 kHz Small Signal Modulation
Fiber	PM630-HP

The information provided in the specifications table is meant to serve as a guideline. However, since each pigtailed laser diode is unique, the specific data is included on a specifications sheet that is shipped with the product.

Modulation In

BNC Female

0 to 5 V Max, 50 Ω

Remote Interlock Input

2.5 mm Mono Jack

2.5 mm Phono Jack

Terminals must be shorted either by included plug or user device, i.e. external switch, for laser mode "ON" to be enabled.

Laser Safety and Classification

Safe practices and proper usage of safety equipment should be taken into consideration when operating lasers. The eye is susceptible to injury, even from very low levels of laser light. Thorlabs offers a range of laser safety accessories that can be used to reduce the risk of accidents or injuries. Laser emission in the visible and near infrared spectral ranges has the greatest potential for retinal injury, as the cornea and lens are transparent to those wavelengths, and the lens can focus the laser energy onto the retina.

Safe Practices and Light Safety Accessories

Laser safety eyewear must be worn whenever working with Class 3 or 4 lasers.
Regardless of laser class, Thorlabs recommends the use of laser safety eyewear whenever working with laser beams with non-negligible powers, since metallic tools such as screwdrivers can accidentally redirect a beam.
Laser goggles designed for specific wavelengths should be clearly available near laser setups to protect the wearer from unintentional laser reflections.
Goggles are marked with the wavelength range over which protection is afforded and the minimum optical density within that range.
Laser Safety Curtains and Laser Safety Fabric shield other parts of the lab from high energy lasers.
Blackout Materials can prevent direct or reflected light from leaving the experimental setup area.
Thorlabs' Enclosure Systems can be used to contain optical setups to isolate or minimize laser hazards.
A fiber-pigtailed laser should always be turned off before connecting it to or disconnecting it from another fiber, especially when the laser is at power levels above 10 mW.
All beams should be terminated at the edge of the table, and laboratory doors should be closed whenever a laser is in use.
Do not place laser beams at eye level.
Carry out experiments on an optical table such that all laser beams travel horizontally.
Remove unnecessary reflective items such as reflective jewelry (e.g., rings, watches, etc.) while working near the beam path.
Be aware that lenses and other optical devices may reflect a portion of the incident beam from the front or rear surface.
Operate a laser at the minimum power necessary for any operation.
If possible, reduce the output power of a laser during alignment procedures.
Use beam shutters and filters to reduce the beam power.
Post appropriate warning signs or labels near laser setups or rooms.
Use a laser sign with a lightbox if operating Class 3R or 4 lasers (i.e., lasers requiring the use of a safety interlock).
Do not use Laser Viewing Cards in place of a proper Beam Trap.

Laser Classification

Lasers are categorized into different classes according to their ability to cause eye and other damage. The International Electrotechnical Commission (IEC) is a global organization that prepares and publishes international standards for all electrical, electronic, and related technologies. The IEC document 60825-1 outlines the safety of laser products. A description of each class of laser is given below:

Class	Description	Warning Label
1	This class of laser is safe under all conditions of normal use, including use with optical instruments for intrabeam viewing. Lasers in this class do not emit radiation at levels that may cause injury during normal operation, and therefore the maximum permissible exposure (MPE) cannot be exceeded. Class 1 lasers can also include enclosed, high-power lasers where exposure to the radiation is not possible without opening or shutting down the laser.
1M	Class 1M lasers are safe except when used in conjunction with optical components such as telescopes and microscopes. Lasers belonging to this class emit large-diameter or divergent beams, and the MPE cannot normally be exceeded unless focusing or imaging optics are used to narrow the beam. However, if the beam is refocused, the hazard may be increased and the class may be changed accordingly.
2	Class 2 lasers, which are limited to 1 mW of visible continuous-wave radiation, are safe because the blink reflex will limit the exposure in the eye to 0.25 seconds. This category only applies to visible radiation (400 - 700 nm).
2M	Because of the blink reflex, this class of laser is classified as safe as long as the beam is not viewed through optical instruments. This laser class also applies to larger-diameter or diverging laser beams.
3R	Class 3R lasers produce visible and invisible light that is hazardous under direct and specular-reflection viewing conditions. Eye injuries may occur if you directly view the beam, especially when using optical instruments. Lasers in this class are considered safe as long as they are handled with restricted beam viewing. The MPE can be exceeded with this class of laser; however, this presents a low risk level to injury. Visible, continuous-wave lasers in this class are limited to 5 mW of output power.
3B	Class 3B lasers are hazardous to the eye if exposed directly. Diffuse reflections are usually not harmful, but may be when using higher-power Class 3B lasers. Safe handling of devices in this class includes wearing protective eyewear where direct viewing of the laser beam may occur. Lasers of this class must be equipped with a key switch and a safety interlock; moreover, laser safety signs should be used, such that the laser cannot be used without the safety light turning on. Laser products with power output near the upper range of Class 3B may also cause skin burns.
4	This class of laser may cause damage to the skin, and also to the eye, even from the viewing of diffuse reflections. These hazards may also apply to indirect or non-specular reflections of the beam, even from apparently matte surfaces. Great care must be taken when handling these lasers. They also represent a fire risk, because they may ignite combustible material. Class 4 lasers must be equipped with a key switch and a safety interlock.
All class 2 lasers (and higher) must display, in addition to the corresponding sign above, this triangular warning sign.

Posted Comments:

user (posted 2021-04-23 01:45:27.227)

In my optical system,maybe about 20% laser power will back reflection into laser source.I am worried about back reflection light will damage laser source.Does this laser source include isolator?Thank you.

YLohia (posted 2021-04-23 11:35:06.0)

Thank you for contacting Thorlabs. Unfortunately, such a high back reflection will damage the source since this doesn't come with an integrated isolator. That being said, a custom fiber based isolator for 635 nm can be ordered using the form on this page (https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=3260) and be used right on the output to reduce the amount of backreflections going into the laser cavity.

user (posted 2019-05-21 14:13:05.223)

In the product description you state "... All of our fiber-pigtailed lasers utilize an angled fiber ferrule at the internal laser/fiber launch point to minimize reflections back into the laser diode, thereby increasing the stability of the laser diode's output." And yet the specifications call out an FC/PC and not an FC/APC. I am confused. Can you please clarify?

YLohia (posted 2019-05-21 03:00:34.0)

Hello, thank you for your feedback and bringing this typo to our attention. The specs are correct -- the items on this page (as of 5/2019) are FC/PC and not FC/APC (APC connections can be quoted as custom items by emailing techsupport@thorlabs.com). I am working with our technical marketing team to get this resolved. Please accept our apologies for any confusion caused by this.

Andrey Kuznetsov (posted 2019-05-01 14:28:16.583)

NOTICE to Customers: I compared 630HP and SM600 fibers when connected to these Fiber sources. These sources have an internal SM600 fiber from the diode to the front bulkhead connector. Thorlabs rightly says to use cables of the same type, however even though 630HP and SM600 share almost exactly the same parameters like NA, etc, based on my tests: 630HP insertion can cause output attenuation up to 95%, while SM600 fiber attenuation was only up to 20%. The issue I had was that when inserting a fiber into the bulkhead, with the key polarizer aligned, rotating and tightening the connector would result in an unpredictable attenuation of light output as measured with a photodiode. We're now switching to SM600 fibers to avoid severe attenuation losses due to fiber coupling issues. Thorlabs should explicitly state this on the Overview page in bold letters that customers must use SM600 fiber to avoid huge attenuation losses due to coupling.

mmcclure (posted 2019-05-02 10:52:01.0)

Hello, thank you for your feedback. Yes, for our single mode fiber-coupled laser sources, we recommend using a single mode patch cable that is the same fiber type as the fiber-pigtailed laser inside the device. We will make this recommendation more explicit on the webpage.

akuznetsov (posted 2018-09-27 19:42:45.16)

What is the fiber core size inside these laser bench sources? What core size fiber patch cable should I use to optimize light throughput?

YLohia (posted 2018-09-28 11:33:03.0)

Hello, the fiber types used are listed in the Specs tab: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=1500&tabname=Specs along with the MFD and NA. In order to maximize coupling efficiency, you should use the same fiber or a multimode fiber with a larger MFD and NA than the one used in the benchtop unit.

akuznetsov (posted 2018-09-27 17:33:36.43)

We have a S1FC637 and we see that 637*2=1274nm wavelength is also present on the output, is this normal? Shouldn't there be a filter in the unit to prevent the doublet from outputting? We are using the 637nm to excite emission in the NIR so the 1274nm output from the laser is interfering with out results.

YLohia (posted 2018-10-03 03:02:17.0)

Hello, thank you for contacting Thorlabs. This is certainly not normal and not expected of a GaAs-based chip. I took a few scans of the S1FC637 with our OSA207C optical spectrum analyzer and did not find any significant emission around 1274nm (at max output power setting). Based on our correspondence, the issue was being caused by the small fraction of the stimulus light (1274nm) being fed into the spectrometer since the stimulus and collection path were the same.

melanie (posted 2018-09-04 08:20:38.627)

1.What is the laser threshold power for S1FC635PM ? 2.Would you consider making a PM fibre-coupled green laser ?

nbayconich (posted 2018-09-25 10:17:46.0)

Thank you for contacting Thorlabs. We do not specify a threshold power for the S1FC635PM benchtop source however the setpoint resolution is 0.01mW and can be adjusted from 0 - 2.5mW. The threshold current for the diode is about 50mA and the minimum range is set to just below the lasing threshold. The output is mostly off but there will be a very small amount of light still present since a small amount of light is needed for the power control circuit to be active. I will reach out to you directly to discuss our custom capabilities.

melanie (posted 2017-03-23 13:05:57.74)

I have 2 questions: 1) If connected to one of your PM patchcords, what will be the typical polarisation extinction when the light emerges from the patchcord ? 2) If we turn the laser right down, will it become incoherent ? (this is useful to us) Thanks, Melanie

tfrisch (posted 2017-03-30 01:17:52.0)

Hello Melanie, thank you for contacting Thorlabs. When used with a PM patch cable, S1FC635PM has an extinction ratio of >20dB. As for the laser power, this unit is not intended for operation below the threshold current of the diode. I will reach out to you directly to discuss your application.

acable (posted 2008-08-15 10:52:31.0)

Related Products… please think about the related products that are most often used with the product that is being featured. In the case of the fiber coupled laser sources it would probably be: patch cable, collimation package, and perhaps a mirror mount and adapter to hold and aim the collimated light field. I would even think about adding a little text by each price box with a labeled photo of the parts all connected together, with a kit being offered for each of the wavelengths. I would then use the Related Products links (and refer to them in the text) to allow the customer to put together their own parts list (longer cables, different collimation packages, different mounts).

Single Mode Fiber-Coupled Laser Sources

Zoom

Five Wavelengths Available from 405 to 675 nm
Single Mode, FC/PC Fiber Interface
Minimum Full Output Powers of up to 15 mW
Fiber Patch Cables Sold Separately
Custom Wavelengths Available; Contact Tech Support

These Single Mode Fiber-Coupled Laser Sources conveniently package a pigtailed Fabry-Perot laser diode and current controller into a single benchtop unit. The Fabry-Perot laser diode inside each unit is pigtailed to a single mode fiber that is terminated at an FC/PC bulkhead (wide and narrow key compatible) attached to the front panel of the unit. Thorlabs offers single mode fiber optic patch cables for connecting to the bulkhead on the front panel. To minimize losses, we recommend using a fiber patch cable that is the same fiber type as the fiber-pigtailed laser; refer to the Specs tab for the internal fiber type used for the pigtail. Additionally, to reduce noise from back reflections, we recommend that a hybrid FC/PC to FC/APC cable be used with the FC/PC end connected to the laser source.

Also found on the front panel is a display that shows the output power in mW, an on/off key, an enable button, and a knob to adjust the laser power. The back panel includes an input that allows the laser diode drive current to be controlled via an external DC or sine wave voltage source and a remote interlock input.

Note: The laser must be off when connecting or disconnecting fibers from the device, particularly for power levels above 10 mW.

For applications using a 635 nm source, Thorlabs also offers a compact fiber-coupled laser source with a USB interface. For optogenetics applications, Thorlabs offers a 473 nm benchtop laser source below that incorporates multimode fiber. For a polarized output, laser sources that incorporate polarization-maintaining fiber are also available below. For telecom applications that require tunable output, please see our benchtop tunable telecom laser sources. For laser sources with custom wavelengths or with an FC/APC fiber interface, please contact Tech Support.

Multimode Fiber-Coupled Laser Source

Zoom

Output Wavelength: 473 nm
Multimode FC/PC Fiber Interface
50 mW Power Output
Fiber Patch Cables Sold Separately

The S1FC473MM Fiber-Coupled Laser provides 50 mW of output power and a wavelength of 473 nm, making it an ideal source for many Optogenetics applications. It includes a pigtailed FP laser diode and current controller in a single benchtop unit. The unit's output can also be externally modulated at 5 kHz full depth/30 kHz small signal. The output is a FG105UCA multimode fiber terminated at an FC/PC connector. The unit is compatible with our extensive line of multimode patch cables and optogenetics equipment.

The front panel includes a display that shows the output power in mW, an on/off key, an enable button, and a knob to adjust the laser power. The back panel includes an input that allows the laser diode drive current to be controlled via an external voltage source and a remote interlock input. For complete operating instructions, please refer to the manual, available by clicking the red Docs icon ( docs icon ) below.

Note: The laser must be off when connecting or disconnecting fibers from the device, particularly for power levels above 10 mW.

We also offer fiber-coupled LEDs as well as other fiber-coupled laser sources.

Polarization-Maintaining Fiber-Coupled Laser Source

Zoom

Output Wavelength: 635 nm
Single Mode Polarization-Maintaining FC/PC Fiber Interface
Minimum Full Output Power of 2.5 mW
Fiber Patch Cables Sold Separately
Slow Axis of the PM Fiber Aligned to the Narrow Key of the FC/PC Bulkhead Connector
Custom Visible Wavelengths Available; Contact Tech Support

These Polarization-Maintaining Fiber-Coupled Laser Sources package a pigtailed Fabry-Perot laser diode inside each benchtop unit. The laser diode is pigtailed to a single mode PM fiber that is terminated at an FC/PC bulkhead attached to the front panel of the unit. During the pigtailing process, the fiber alignment is actively maintained so that the polarization axis of the laser diode is aligned with the slow-axis of the PM fiber. In addition, the slow-axis of the PM fiber is aligned to the narrow key of the FC/PC bulkhead connector on the front panel of the benchtop unit. Thorlabs offers polarization-maintaining fiber optic patch cables for connecting to the bulkhead on the front panel. To minimize losses, we recommend using a fiber patch cable that is the same fiber type as the fiber-pigtailed laser; refer to the Specs tab for the internal fiber type used for the pigtail. Additionally, to reduce noise from back reflections, we recommend that a hybrid FC/PC to FC/APC cable be used with the FC/PC end connected to the laser source.

Also found on the front panel is a display that shows the output power in mW, an on / off key, an enable button, and a knob to adjust the laser power. The back panel includes an input that allows the laser diode drive current to be controlled via an external voltage source and a remote interlock input.

Note: The laser must be off when connecting or disconnecting fibers from the device.