Fiber-Coupled Xenon Light Source

  • 75 W Xenon Short-Arc Bulb with 240 - 1200 nm Output
  • Long 2000 Hour Lifespan
  • SMA905 Fiber-Coupled Output
  • Compatible with SM1 Components and 30 mm Cage Systems


Xenon Light Source


Replacement Xenon Bulb (Not to Scale)

Application Idea

The SLS205 Light Source in a Free-Space Configuration with 30 mm Cage System Components and SM1-Threaded Components

Related Items

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Xenon lamp fiber-coupled
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The SLS205 fiber-coupled light source shown with the included M111L01 solarization-resistant patch cable.
deuterium lamp front
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Click for Raw Data
The measured spectral power distribution for the SLS205 light source. The spectrum is plotted on a log scale so that both the underlying shape and spectral lines are visible.


  • Xenon Short Arc Light Source for 240 - 1200 nm
  • 75 W Xenon Bulb with a 1.3 mm Arc Gap
  • Removable SMA905 Fiber Adapter
  • Internally SM1-Threaded (1.035"-40) Aperture
  • BNC Port for External CMOS Shutter Control
  • 0.12% Per Hour and 0.1% Per °C Output Power Drift
  • Compatible with 30 mm Cage System and Ø1" Lens Tubes
  • Replacement Xenon Bulb Available Separately
  • Location-Specific Power Cord Included

Thorlabs' SLS205 Fiber-Coupled Xenon Light Source provides illumination from 240 nm to 1200 nm with intense lines between 800 nm and
1000 nm. The strong continuous spectrum at UV and visible wavelengths (240 - 700 nm) makes this an ideal source for UV and visible spectroscopy applications. This light source also emits at wavelengths out to 1200 nm, allowing for use with near-infrared-light applications. A constant power supply stabilizes the 75 W bulb, which has a short arc gap of 1.3 mm to support high coupling efficiency when used with the included patch cable. The shutter in the SLS205 light source can be controlled manually via the switch on the front panel or externally via a 0 to 5 V CMOS BNC port on the back panel. A fan cools the light source and bulb, enabling continuous operation for >30 hours (see the Graphs tab for lamp stability).

The SLS205 light source comes equipped with an SMA905 fiber adapter on the output aperture and ships with a SMA to SMA Solarization-Resistant Multimode Fiber Patch Cable (Item # M111L01). The fiber adapter can be removed so the lamp functions as a free-space source. The removal of the fiber adapter also exposes the internal SM1 (1.035"-40) threading, which can connect other externally SM1-threaded fiber adapters. The minimum fiber-coupled output power is 3.5 mW using the included patch cable and 290 mW when used in a free-space configuration. For more information on the output power and radiance of compatible Thorlabs fiber patch cables and liquid light guides, see the Output Coupling tab.

Four 4-40 tapped holes on the front panel are designed for 30 mm cage rods to provide compatibility with 30 mm cage system components. Using the cage system, it is possible to incorporate various optic mounts that are centered along the optical center of the lamp (as pictured in the image to the upper right).

Within the light source housing is a xenon bulb and a series of lenses to focus the emitted light into the fiber port. A mirror placed behind the bulb helps to increase the coupling efficiency. Within the bulb, an electric arc is generated that excites the gaseous xenon, causing emission of a broadband spectrum that ranges from UV into near-infrared wavelengths. The xenon bulb in the SLS205 light source has a lifetime of 2000 hours. A status LED on the front panel indicates when the unit is functioning normally or if an issue occurs, such as overheating or the bulb nearing the end of its lifetime. Additionally, the bulb power can be monitored via a BNC port on the back panel that provides a voltage feedback signal from a photodiode inside the housing. Replacement bulbs can be purchased separately below. Please see the Bulb Installation tab for detailed instructions on how to install and replace the bulb in these lamps.

Please note that the SLS205 light source generates high-intensity UV light. Wear appropriate eye protection and do not look directly at the output during operation. Do not place hands or body parts in the path of the beam.

Item # SLS205
Wavelength Range 240 - 1200 nm
Bulb Electrical Power 75 W
Included Output Fiber M111L01 Patch Cable
Ø105 µm, 0.22 NA, SMA905 Connectors
Fiber-Coupled Output Powera 3.5 mW (Minimum)
Free-Space Output Powerb 290 mW (Typical)
Fiber-Coupled Color Temperaturea 5400 K (Typical)
Free-Space Color Temperatureb 5800 K (Typical)
Output Power Drift 0.12% Per Hour (Typical)
0.1% Per °C (Typical)
Output Power Stabilityc <0.5%
Bulb Lifetimed 2000 h
Bulb Arc Gap 1.3 mm
Shutter Switch Time 5 ms
Shutter Repetition Rate (Max) 10 Hz (Burst)
Bulb Power Monitor 0 - 5 V Analog
External Shutter Control 0 - 5 V CMOS
High: 3.8 - 5 V, Low: 0 - 1.5 V
Power Supply 100 - 240 VAC, 50 - 60 Hz
Operating Temperature 0 - 45 °C
Storage Temperature -15 - 70 °C
Dimensions (L x W x H) 325.6 mm x 162.5 mm x 162.8 mm
(12.82" x 6.40" x 6.41")
  • Measured with M111L01 Fiber Patch Cable at Beginning of Bulb Lifetime
  • Measured at the Output Port with the Fiber Adapter Removed at Beginning of Bulb Lifetime
  • Standard deviation of optical power measured at room temperature over a 1 hour period (after 45 minutes of warm-up) with a 1 Hz sampling rate.
  • Defined as the time it takes for the bulb to decrease to ≤50% of the initial output intensity.
SLS205 Front Panel
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SLS205 Xenon Light Source Front Panel
SLS205 Front Panel
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SLS205 Xenon Light Source Back Panel
Patch Cable Item # M111L01
Wavelength Range 180 - 1200 nm
NA 0.22
Core Diameter 105 ± 2.1 µm
Cladding Diameter 125 ± 1 µm
Coating Diameter 250 ± 10 µm
Bend Radius (Short Term) 16 mm
Bend Radius (Long Term) 32 mm
Length 1 m
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Click for Raw Data
The measured spectral power distribution for the SLS205 lamp.
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Click for Raw Data
The output of the SLS205 lamp over 30 hours of continuous operation. This graph does not include 45 minutes of warm-up to ignite the source and stabilize the output.
Bulb Handling
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The bulb should be held by the handle with gloved hands. Avoid making contact with the bulb envelope directly.

Bulb Handling

The bulbs used in a xenon lamp operate at a very high temperature. If handled incorrectly, they will become a serious hazard to users and could potentially cause severe injury. It is critical to follow safety instructions when handling them.

The guidelines below describe correct bulb handling.

  • Any dust or grease on the bulb will compromise the integrity of the bulb envelope, increasing the chance that the bulb will burst. Clean any dirt, oil, or lint away from the bulb with alcohol and a lint free cloth or tissue.
  • Never bump, drop, apply excessive stress to, or scratch the bulb. This could cause it to burst.
  • Always transport the bulb in the provided protective case or cover until installation.
  • Save the protective case or cover and packaging materials (box) for bulbs that have been used to their rated service life.
  • Always wear gloves when handling the bulb; never hold the bulb by its envelope (see photo to the right). Thorlabs offers gloves that can be used for bulb handling.
  • The bulb generates very high-intensity UV light output; wear the appropriate laser safety glasses during operation.
  • The bulb gets very hot during operation. Always wait at least 30 minutes for the bulb to cool down before handling the bulb after operation.
  • Electrostatic discharge (ESD) protection is recommended when handling the bulb.


Bulb Installation

The bulb must be installed in the SLS205 Xenon Light Source before operation. The instructions and photos below detail the recommended procedure for installing the bulb. Do not attempt to change the light bulb while the bulb and unit are hot. Allow at least 30 minutes after turning the lamp off before attempting to replace the light bulb.

We strongly recommend wearing gloves when replacing the bulb to prevent skin oils from being deposited onto the bulb. If you suspect the bulb is dirty, carefully clean it with alcohol before connecting it to a power supply.

Prepare the Bulb for Installation

  1. Remove the bulb base from its original packaging. Always hold the module at its handle. Avoid holding the glass envelope.
  2. Loosen the setscrew on the bulb base by turning it counterclockwise using the included torque driver. Remove the pre-installed dummy bulb.
  3. Carefully place the 75 W Xenon short arc bulb into the bulb base with the cathode facing down. Make sure the bulb slides all the way down the bulb base until it is in contact with the bottom of the slot.
  4. Then, using the same torque driver, turn the setscrew on the side of the bulb base clockwise until the torque driver clicks.

Note: Failure to use the torque driver for installation will likely damage the bulb.

Open the Lamp Housing

  1. Use the included 2 mm (5/64") hex key to loosen the panel screw on the side of the light source.
  2. Grip the bulb cover and pull to remove it.

Secure the Bulb in Place

  1. Slide the bulb base into the optics base on the bottom of the lamp house.
  2. Place the heatsink on the bulb anode.
  3. Turn the thumb screw clockwise to tighten it. The thumbscrew only needs to be finger tight. Applying too much torque on the thumb screw may break the bulb. Replace the side panel and tighten the panel screw with the hex key.

For instructions on removing and replacing the bulb, please refer to steps listed in the manual, which can be accessed by clicking on the red docs icon () below.

SLS205 Bulb Installation
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Step 1: Remove Bulb from Packaging
SLS205 Bulb Installation
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Step 2: Remove Dummy Bulb
SLS205 Bulb Installation
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Steps 3 & 4: Install Bulb in Base
SLS205 Bulb Installation
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Step 5: Loosen Panel Screw
SLS205 Bulb Installation
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Step 6: Remove Bulb Cover
SLS205 Bulb Installation
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Step 7: Slide Bulb into Optics Base
SLS205 Bulb Installation
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Step 8: Place Heat Sink on Bulb Anode
SLS205 Bulb Installation
Click for Details
Step 9: Tighten Thumbscrew

The SLS205 Xenon Light Source is compatible with any SMA-terminated fiber patch cable when using the included SMA905 fiber adapter. For compatibility with our Liquid Light Guides (LLGs), the fiber adapter can be replaced with our AD3LLG or AD5LLG SM1 adapters for LLGs. We recommend several LLGs and multimode solarization-resistant fiber patch cables. These are listed in the table below with the corresponding typical output power and radiance when coupled to the SLS205 light source.

The SLS205 Xenon Light Source's coupling optics are not designed or aligned for a single mode fiber, but it is possible to use a single mode fiber. This would result in a significant drop of coupled power and could result in a high variation of coupled power. Also, we do not recommend using a fiber patch cable that is not solarization-resistant as it can result in photon darkening and degradation of the fiber patch cable. 

Recommended Patch Cables and LLGs for the SLS205
Patch Cable Item # Wavelength Range NA Core Diameter Output Powera,b Radiancea,c
M111L01d 180 - 1200 nm 0.22 105 ± 2.1 µm 3.5 mW (Min.), 5 mW (Typ.) 3723 mW/sr/mm2 (Typ.)
M112L01 200 ± 4 µm 18 mW (Typ.) 2757 mW/sr/mm2 (Typ.)
M113L01 400 ± 8 µm 52 mW (Typ.) 1673 mW/sr/mm2 (Typ.)
M114L01 600 ± 12 µm 88 mW (Typ.) 960 mW/sr/mm2 (Typ.)
LLG Item # Wavelength Range NA Core Diameter Output Powere Radiancee
LLG3-4T 220 - 650 nm 0.42 3 mm 62 mW (Typ.) 15 mW/sr/mm2 (Typ.)
LLG5-4T 5 mm 66 mW (Typ.) 6 mW/sr/mm2 (Typ.)
LLG03-4H 340 - 800 nm 0.59 3 mm 140 mW (Typ.) 16 mW/sr/mm2 (Typ.)
LLG05-4H 5 mm 147 mW (Typ.) 6 mW/sr/mm2 (Typ.)
LLG3-4Z 420 - 2000 nm 0.52 3 mm 195 mW (Typ.) 30 mW/sr/mm2 (Typ.)
LLG5-4Z 5 mm 204 mW (Typ.) 11 mW/sr/mm2 (Typ.)
  • When coupled to the SLS205 light source using the included SMA905 fiber adapter.
  • This is the total output power which includes the cladding modes.
  • The radiance is calculated based on the output power with the cladding modes removed.
  • Included with the SLS205 light source.
  • When coupled to the SLS205 light source using an SM1 adapter for LLGs. The AD3LLG and AD5LLG adapters were used for LLGs with 3 mm and 5 mm core diameters, respectively.

Posted Comments:
Florian Foschum  (posted 2021-04-23 01:59:16.913)
Hello, can you please provide me spectral data for this light source using a 600 µm or even a 1000 µm optical fiber (180 to 1200 nm) in mW/nm? Best regards, Florian Foschum
YLohia  (posted 2021-04-26 01:57:13.0)
Hello Florian, thank you for contacting Thorlabs. We will reach out to you directly with some spectrum data.
YI Yang  (posted 2020-11-26 09:43:32.463)
Dear Thorlabs, 您好,请问你们这款氙灯方便发我一份excel或者txt的光谱数据吗? 杨翼, 上海睿励科学仪器 谢谢!
YLohia  (posted 2020-12-01 10:30:47.0)
An applications engineer from our team in China ( will reach out to you directly.

Below is a selection guide for all of our white-light, broadband, lamp-based light sources. In addition to these sources, Thorlabs also offers unmounted white-light LEDs, white-light mounted LEDs, white-light fiber-coupled LEDs, and high-powered, white-light Solis® LEDs.

Broadband Light Source Selection Guide
Item # (Click to
Not to Scale)
Emitter Type Wavelength
(Click for Plot)
Output Coupling Output Power Lamp
SLS204 Deuterium 200 - 700 nm Free Space or
Fiber Coupled (SMA)
2 mWa
0.1 mWb
30 W N/A 2000 hc SLS254B
SLS205 Xenon Arc 240 - 1200 nm Free Space or
Fiber Coupled (SMA)
290 mWa
5 mWd
75 W 5800 Ka
5400 Kd
2000 hc SLS255B
SLS401 Xenon Arc 240 - 2400 nm Free Spacee >1.3 Wa 150 W 5800 K 2000 hc SLS401Bf
or SLS402B
SLS402 Mercury-Xenon Arc 240 - 2400 nm Free Spacee >1.3 Wa 150 W 6000 K 2000 hc SLS401B
or SLS402Bf
SLS302 Quartz
360 - 2500 nm Free Spacee >10 Wa 150 W 3400 K 1000 hg SLS301B
SLS201L(/M) Quartz
360 - 2600 nm Free Spacee or
Fiber Coupled (SMA)
500 mWa
10 mWh
9 W 2796 K 10 000 h SLS251
SLS301 Quartz
360 - 3800 nm Free Spacee >1.6 Wa 150 W 3400 K 1000 hg SLS301B
SLS603 Xenon Arc 380 - 780 nm Ø3 mm
Liquid Light Guide
>7 Wh 300 W 6000 Ki 1000 hc SLS600B
SLS605 Xenon Arc 380 - 780 nm Ø5 mm
Liquid Light Guide
>15 Wh 300 W 6000 Ki 1000 hc SLS600B
OSL2 Tungsten-Halogen 400 - 1600 nm
Fiber Bundle 1.4 Wk 150 W 3200 K 1000 hc OSL2Bf,
OSL2IR Tungsten-Halogen 400 - 1750 nm
Fiber Bundle 3.8 Wk 150 W 3200 K 200 hc OSL2B,
QTH10(/M) Quartz
400 - 2200 nm Free Space 50 mW (Typ.) 10 W 2800 Kl (Typ.) 2000 h QTH10B
SLS203L(/M) Silicon Carbide Globar 500 nm - 9 µm Free Space >1.5 Wa 24 W 1500 K 10 000 h SLS253
SLS303 Silicon Nitride Globar 550 nm - 15 µm Free Space 4.5 Wa 70 W 1200 K 5000 hg SLS303B
  • Free-space optical power measured without adapters at the beginning of lamp lifetime.
  • Measured with Thorlabs' M114L01 solarization-resistant patch cable at beginning of lamp lifetime.
  • Operation time before the maximum optical output power of the lamp reaches 50% of its original output.
  • Measured with Thorlabs' M111L01 solarization-resistant patch cable at beginning of lamp lifetime.
  • Adapters are available separately to couple the free-space output into liquid light guides (LLGs).
  • This lamp is identical to the original lamp that comes with the light source.
  • Operation time before the controller cannot stabilize the output power of the lamp.
  • Measured at the liquid light guide tip at the beginning of lamp lifetime.
  • Prior to LLG
  • Fiber-coupled optical power, measured with included fiber patch cable at beginning of lamp lifetime.
  • Power at Fiber Tip at Maximum Lamp Intensity
  • Color temperature will vary from unit to unit.
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Fiber-Coupled Xenon Light Source

Based on your currency / country selection, your order will ship from Newton, New Jersey  
+1 Qty Docs Part Number - Universal Price Available
SLS205 Support Documentation
SLS205Fiber-Coupled Xenon Light Source, 240 - 1200 nm
SLS255B Support Documentation
SLS255BReplacement Xenon Bulb for the SLS205 Light Source