Stabilized Deuterium UV Light Source

200 - 700 nm Output with Continuous UV Spectrum from 200 - 400 nm
Long 2000 Hour Lifespan
SMA905 Fiber-Coupled Output
Compatible with SM1 Components and 30 mm Cage Systems

SLS204

Deuterium Light Source

Application Idea

SLS204 Shown with Included M114L01 Solarization-Resistant Patch Cable

SLS254B

Replacement Deuterium Bulb (Not to Scale)

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Overview
Specs
Graphs
Bulb Replacement
Feedback
Lamp Selection Guide

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The fiber adapter and dust cap on the output port can be removed to use 30 mm cage system components and SM1-threaded components with the SLS204.

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The measured spectral power distribution for the SLS204 Light Source. The blue-shaded region indicates the lamp's operating wavelength range. Click here for raw data.

Features

Deuterium Light Source for 200 - 700 nm
Stabilized 30 W Bulb Intensity Using Closed-Feedback Loop
0.02% Per Hour and 0.1% Per °C Output Power Drift
SMA905 Fiber-Coupled Output with Dust Cover
Internally SM1-Threaded (1.035"-40) Aperture
Compatible with 30 mm Cage Systems and Ø1" Lens Tubes
Replacement Light Bulb Available Separately
Location-Specific Power Cord Included

Thorlabs' SLS204 Deuterium Light Source provides stable illumination from 200 nm to 700 nm. The strong continuous spectrum at short UV wavelengths (200 - 400 nm) makes this an ideal source for UV spectroscopy applications. A closed-loop feedback system stabilizes the 30 W bulb which is coupled into a SMA905 bulkhead for connecting to a fiber patch cable. A low-noise fan cools the light source and bulb enabling continuous operation for >50 hours (see the Graphs tab for lamp stability over time). Each SLS204 includes a location-specific power cord.

The SLS204 includes a M114L01 Solarization-Resistant Multimode Fiber Patch Cable. The light source has a typical fiber-coupled output power of 0.1 mW using the included patch cable and a typical 2 mW output power when used in a free-space configuration.

Within the light source housing is a deuterium bulb and a series of UV fused silica lenses to focus the emitted light on the fiber port. Within the bulb, an electric arc is generated that excites the gaseous deuterium causing molecular emission of a continuous UV spectrum. In addition, two other major spectrum peaks occur at 486 nm and 656 nm. The deuterium bulb in the SLS204 has a lifetime of 2000 hours. Replacement bulbs are available for purchase separately. Please see the Bulb Replacement tab for detailed instructions on how to replace the bulb in these lamps.

The SLS204 comes equipped with an SMA905 fiber adapter on the output aperture and a hinged dust cap. The adapter can be removed to expose internal SM1 (1.035"-40) threading that is compatible with other externally SM1-threaded fiber adapters. The dust cap can also be removed using the included 5/64" hex key or balldriver in order to access the two of the four 4-40 tapped holes for 30 mm cage rods that 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 seen in the image above).

Please note that the SLS204 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 #	SLS204
Wavelength Range	200 - 700 nm
Bulb Electrical Power	30 W
Output Fiber	M114L01 Patch Cable (Included) Ø600 µm, 0.22 NA, SMA905 Connectors
Fiber-Coupled Output Power^a	0.1 mW (Typical)
Free-Space Output Power^b	2 mW (Typical)
Output Power Drift	0.02% Per Hour (Typical) 0.1% Per °C (Typical)
Output Power Stability^c	<0.06%
Bulb Lifetime^d	2000 h
Power Supply	100 - 240 VAC, 50 - 60 Hz
Operating Temperature	0 - 40 °C
Storage Temperature	-15 - 70 °C
Dimensions (L x W x H)	246.3 mm x 170.0 mm x 129.8 mm (9.70" x 6.69" x 5.11")

Measured with M114L01 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 at 230 nm.

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SLS204 Front Panel

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SLS204 Back Panel

Patch Cable Item #	Wavelength Range	NA	Core Diameter	Cladding Diameter	Coating Diameter	Bend Radius (Short Term)	Bend Radius (Long Term)
M114L01	180 - 1200 nm	0.22	600 ± 12 µm	660 ± 6 µm	750 ± 20 µm	53 mm	106 mm

Click to Enlarge
The measured spectral power distribution for the SLS204 Light Source. The blue-shaded region indicates the lamp's operating wavelength range. The continuous spectrum of the deuterium lamp extends from 200 nm - 400 nm. Please note that the lower apparent intensity of the output is due to detection limitations from 300 to 400 nm and <225 nm.

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The output of the SLS204 over 50 hours of continuous operation. This graph does not include 45 minutes of warm-up to ignite the source and stabilize the output.

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The bulb can be held by the metal casing with gloved hands. Avoid making contact with the bulb envelope directly.

Bulb Handling

The bulbs used in a deuterium 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, 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 10 minutes for the bulb to cool down before handling the bulb after operation.
Electrostatic discharge (ESD) protection is recommended when handling the bulb.

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Step 3: Press Clamps and Pull Connector

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Step 2: Remove the Bulb Cover

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Step 1: Loosen Panel Screw

Click for Details
Step 6: Replace with New Bulb

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Step 5: Remove Bulb from Holder

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Step 4: Unscrew Bulb

Bulb Installation

The instructions and photos to the right detail the recommended procedure for replacing the bulbs in the SLS204 Deuterium Light Source. Do not attempt to change the light bulb while the bulb and unit are hot. Allow at least 10 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.

Open the Lamp Housing

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

Remove the Old Bulb

Press the two clamps on the sides of the connector at the same time and pull the connector from the socket to electrically disconnect the bulb.
Use the 2 mm (5/64") hex key to remove the two cap screws holding the bulb within the lamp.
Pull out the bulb by the metal housing; do not touch the bulb envelope.

Install the New Bulb

Place the replacement bulb within the lamp aligning the slot in the bulb base with the pin on the front side of the bulb holder. Tighten the two cap screws with the hex key and plug in the black connector to connect the bulb. Afterwards, replace the side panel and tighten the panel screw with the hex key.

Posted Comments:

Raymond Garcia (posted 2023-12-18 17:37:57.87)

to whom it may concern: can you tell me it this product, SLS204, is UL-listed? Thank you. ray

ksosnowski (posted 2023-12-21 09:24:51.0)

Thank you for contacting Thorlabs. The SLS204 is not UL-listed.

Chih-Chun Hsu (posted 2022-01-19 03:40:40.417)

Hello sir, We bought a SLS204 last December However the intensity of the output light is changing through time. Is there anything we may check? Or may I turn off the light corrections? Thank you Best wishes Jim

YLohia (posted 2022-01-20 03:20:56.0)

Thank you for contacting Thorlabs. The SLS204 is equipped with an internal feedback loop to ensure a constant output intensity. Please allow 45 minutes to 1 hour for the light source to stabilize and reach a state of equilibrium. It is not possible to turn off this correction feature. The measured power fluctuations are usually dependent on the measurement method used. We will contact you directly to discuss this further.

user (posted 2021-01-28 12:08:30.307)

The describtion for the SLS204 says that a "series of UV fused silica lenses to focus the emitted light on the fiber port" and that the fiber port can be dismounted and Ø1" optics can be used instead. My question is what sort of lenses is needed to create a Ø1" or Ø1/2" collimated beam? Kind regards, Jesper Skottfelt

YLohia (posted 2021-02-01 10:07:53.0)

Thank you for contacting Thorlabs. With the fiber adapter removed, this can operate as a free-space light source. The NA of the source is roughly 0.50, which would make it quite hard to properly collimate and you will need an even higher NA lens in order to do so. We recommend these high NA UV Fused Silica aspheric lenses for collimating the Dt light source (https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=14329). Please note that the output beam cannot be perfectly collimated, since it is a lamp and not a laser.

masonkn608 (posted 2019-01-02 16:24:20.267)

Can you advise a filter to remove the visible lines from the deuterium lamp SLS204, but still passs 200-400nm? Regards, Ken Mason

YLohia (posted 2019-01-03 09:13:37.0)

Hello Ken, thank you for contacting Thorlabs. Unfortunately, we currently do not offer a short pass filter that passes the UV region and blocks the visible light. I have posted your request on our internal engineering forum for further consideration.

ktothejw (posted 2018-07-16 22:11:31.62)

Unlike the equipment spec, the intensity is greatly reduced around 275 nm (using CCS200). If you give me mail, I will send the data together. Best regard.

YLohia (posted 2018-07-17 08:42:59.0)

Hello, thank you for contacting Thorlabs. In general, you can reach us via email at techsupport@thorlabs.com. That being said, this attenuation is to be expected when using the CCS200. For one, amplitude correction is not available below 380nm, so the spectrum curves will not be true. To add to that, a large difference in the relative response of the system from the UV to the visible inhibits reliable power readings in the UV when performing broadband measurements. Features in the UV may still be visible with the use of a bandpass or shortpass filter to prevent saturation at longer wavelengths.

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 Enlarge; Not to Scale)	Emitter Type	Wavelength Range (Click for Plot)	Output Coupling	Output Power	Lamp Electrical Power	Color Temperature	Lamp Lifetime	Replacement Lamp
SLS204		Deuterium	200 - 700 nm	Free Space or Fiber Coupled (SMA)	2 mW^a 0.1 mW^b (Typ.)	30 W	N/A	2000 h^c	SLS254B
SLS205		Xenon Arc	240 - 1200 nm	Free Space or Fiber Coupled (SMA)	290 mW^a 5 mW^d (Typ.)	75 W	5800 K^a 5400 K^d	2000 h^c	SLS255B
SLS401		Xenon Arc	240 - 2400 nm	Free Space^e	>1.3 W^a	150 W	5800 K	2000 h^c	SLS401B^f or SLS402B
SLS402		Mercury-Xenon Arc	240 - 2400 nm	Free Space^e	>1.3 W^a	150 W	6000 K	2000 h^c	SLS401B or SLS402B^f
SLS302		Quartz Tungsten-Halogen	360 - 2500 nm	Free Space^e	>10 W^a	150 W	3400 K	1000 h^g	SLS301B
SLS201L(/M)		Quartz Tungsten-Halogen	360 - 2600 nm	Free Space^e or Fiber Coupled (SMA)	500 mW^a 10 mW^h	9 W	2796 K	10 000 h	SLS251
SLS301		Quartz Tungsten-Halogen	360 - 3800 nm	Free Space^e	>1.6 W^a	150 W	3400 K	1000 h^g	SLS301B
SLS603		Xenon Arc	380 - 780 nm	Ø3 mm Liquid Light Guide	>7 W^h	300 W	6000 Kⁱ	1000 h^c	SLS600B
SLS605		Xenon Arc	380 - 780 nm	Ø5 mm Liquid Light Guide	>15 W^h	300 W	6000 Kⁱ	1000 h^c	SLS600B
OSL2		Tungsten-Halogen	400 - 1600 nm (Typical)	Fiber Bundle	1.4 W^k	150 W	3200 K	1000 h^c	OSL2B^f, OSL2B2, or OSL2BIR
OSL2IR		Tungsten-Halogen	400 - 1750 nm (Typical)	Fiber Bundle	3.8 W^k	150 W	3200 K	200 h^c	OSL2B, OSL2B2, or OSL2BIR^f
QTH10(/M)		Quartz Tungsten-Halogen	400 - 2200 nm	Free Space	50 mW (Typ.)	10 W	2800 K^l (Typ.)	2000 h	QTH10B
SLS203F(/M)		Silicon Carbide Globar	500 nm - 9 µm	Free Space^e or Fiber Coupled (SMA)	1.8 W^a	24 W	1500 K	10 000 h	SLS253
SLS303		Silicon Nitride Globar	550 nm - 15 µm	Free Space	4.5 W^a	70 W	1200 K	5000 h^g	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.