Fixed Magnification Beam Expanders: Mid-Infrared


  • 2X, 5X, or 10X Beam Expansion
  • Sliding Lens Design for Collimation Adjustment
  • ZnSe Optics Ideal for CO2 and QCL Laser Applications
  • AR Coated for 7 - 12 μm

Output

Input

GBE02-E3

2X Magnification

GBE10-E3

10X Magnification

Application Idea

The GBE05-E3 Mounted in a KM200 Kinematic Mount using the SM2A21 Adapter

Related Items


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5X MidIR Beam Expander
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The 5X magnfication beam expander has an M43 x 0.5-threaded output.
2X MidIR Beam Expander
Click for Details

The 2X magnfication beam expander has an SM1-threaded output.
10X MidIR Beam Expander
Click for Details

The 10X magnfication beam expander has an M43 x 0.5-threaded output.

Features

  • 2X, 5X, or 10X Beam Expansion
  • Optics Made from ZnSe Substrate
  • Broadband AR Coated for Wavelengths from 7 - 12 μm
  • Sliding Lens Collimation Adjustment Minimizes Beam Walk Off
  • Housing with Fixed Mechanical Length and Non-Rotating Ends
  • Lockable Collimation Adjustment Ring
  • Threaded Apertures for Easy Integration into Optical Systems
  • Custom Broadband and V Coatings Available (Contact Tech Support)

Thorlabs' Mid-Infrared Beam Expanders can expand or reduce the diameter of a collimated beam by a factor of 2, 5, or 10. These Galilean beam expanders use a low-aberration, air-spaced design optimized to provide a wavefront error of less than λ/4 (i.e., diffraction-limited performance) and minimize the impact on the M2 value of the expanded beam. An expanded beam can be focused to a narrow diffraction-limited waist, allowing an optical system to achieve a higher power density at its focal point.

The beam expanders feature lenses with a broadband AR coating optimized for the 7 - 12 μm spectral range to minimize reflections at the air-to-glass interfaces. The optics themselves are made from ZnSe, which is an optical substrate that has a wide transmission band extending from the red portion of the visible spectrum to the mid-IR. As a result, these beam expanders are suitable for applications requiring CO2 lasers, which operate at 10.6 μm, or other infrared sources, like our quantum cascade lasers. See the Specs and AR Coatings tabs for more information on the coating performance. Contact tech support if you require a quote for a custom broadband or V coating to optimize performance in a particular wavelength region.

The sliding lens design allows for the collimation to be adjusted while minimizing the beam walk-off effect that is inherent to lens adjustments. The red ring, shown in the photos to the right, adjusts the output beam collimation; once the desired collimation is obtained, the ring can be locked by tightening the locking screw using a 0.05" (1.3 mm) ball driver or hex key (not inlcuded).

Mounting Options
These Galilean beam expanders have threaded input and output apertures, which allow additional lenses and filters to be installed easily along the optical axis of the beam expander. The input of each beam expander has internal SM05 (0.535"-40) and external SM1 (1.035"-40) threads for ease of use with Thorlabs' lens tubes and other optical components. The output of the 2X beam expanders is externally SM1 threaded as well. The beam expanders with 5X or 10X expansion have an externally M43 x 0.5-threaded output, which can be integrated with SM2 (2.035"-40) threaded components by using the SM2A30 adapter. All housings are designed so that the mounting surface and threaded ends do not rotate when turning the collimation adjustment ring, allowing the user to adjust the divergence without disturbing any attached optics and maintain pointing stability.

The Ø1.2" section of the barrel on the 2X, 5X, and 10X beam expanders provides a smooth mounting surface with the same diameter as our Ø1" lens tubes. Below we provide a variety of adapters that allow users to mount these expanders on an optical post, in a cage system, or in a kinematic mount. We also offer the SM1A52 adapter, which allows the input to be mated with components using the M30 x 1.0 thread standard.

Thorlabs offers other fixed magnification beam expanders with UV fused silica optical elements for narrowband applications, achromatic designs for broadband applications, or reflective designs that use mirrors for cases where chromatic aberration is a concern. Variable magnification beam expanders, including our UV fused silica or achromatic zoom beam expanders, are also available. For more information on our extensive line of beam expanders, please see the Beam Expanders tab.

Handling ZnSe Optics
The optics inside the beam expander are made from ZnSe, a hazardous material. For your safety, please follow all proper safety precautions should you need to handle these lenses, including wearing gloves and thoroughly washing your hands afterward. Click here to download a pdf of the MSDS for ZnSe.

Thorlabs will accept all ZnSe lenses back for proper disposal. Please contact Tech Support to make arrangements for this service.

Item # Prefix GBE02 GBE05 GBE10
Expansion 2X 5X 10X
Max Input Beam Diametera 9.5 mm 6.7 mm 3.5 mm
Diffraction-Limited Input Beam Diametera,b 9.5 mm 5.0 mm 3.5 mm
Input Thread Internal: SM05 (0.535"-40)
External: SM1 (1.035"-40)
Output Thread External SM1 (1.035"-40) External M43 x 0.5c
Typical Total Transmission 94%
Surface Quality 80-50 Scratch-Dig
Housing Dimensions
Input Housing Diameter 30.5 mm (1.20")d
Output Housing Diameter 30.5 mm (1.20")d 45.0 mm (1.77")
Housing Length 52.0 mm (2.05") 85.5 mm (3.37") 135.0 mm (5.31")
Mounting Optionse SM1RC(/M), SM1TC, CP36, SM2A21 SM1RC(/M), SM1TC, CP36, SM2A21, SM2A30
  • For a Collimated Beam
  • Maximum Input Beam Diameter for Output Peak-to-Valley Wavefront Error (WFE) <λ/4 with Refocusing
  • The SM2A30 thread adapter can be used to integrate these beam expanders with our SM2-Threaded Lens Tubes and 60 mm Cage System.
  • This is the same diameter as our SM1-Threaded Lens Tubes. See below for recommended mounting options.
  • The options in this row are available below. The beam expanders can also be integrated with various threaded components using our thread adapters.

AR Coating Specifications
Item # Suffix -E3
AR Coating Range  7 - 12 μm
Average Reflectance per Surfacea Ravg < 1.0%
Absolute Reflectance per Surfacea Rabs < 2.0%
Damage Thresholdb 5 J/cm2 (10.6 µm, 100 ns, 1 Hz, Ø0.478 mm)
  • Each beam expander has two elements for a total of four coated surfaces.
  • The maximum power that the beam expander can accept is limited by the AR Coating Damage Threshold.

The graph below shows the reflectance per surface with respect to wavelength of the AR coating deposited on both sides of each lens incorporated in our Mid-IR Galilean beam expanders. Each beam expander has two optical elements coated on each side, totaling four coated surfaces. The blue shaded region indicates the wavelength range specified for the -E3 coating. The table below provides the coating specifications.

Triplet Collimator Coating Reflectance
Click to Enlarge
Click Here for Raw Data
The blue shaded region indicates the specified operating wavlength range for the coating. Performance outside of this region is not guaranteed.
Antireflection Coating
Item # Suffix Wavelength Range Reflectance per Surface
-E3 7 - 12 μm Ravg < 1.0%
Rabs < 2.0%

    Optical Coatings and Substrates

    Prolonged use of beam expanders with high-power beams can cause the housing of the beam expander to become hot. The measured temperature rise of our GBE02-E3 and GBE10-E3 mid-infrared beam expanders during use with high-power CW beams is shown in the graphs below. A CW CO2 laser operating at 10.6 µm with powers of 80 W and 200 W was applied for separate trials of 40 minutes each. The input beam had a diameter of 9.5 mm for the trials with the GBE02-E3 and a diameter of 3.5 mm for the trials with the GBE10-E3. Thermocouples were attached at both the input and output sides of the beam expanders while a third thermocouple was placed in air to record the ambient room temperature.

    After 40 minutes of use with an 80 W beam, the temperature of the GBE02-E3 housing reached a temperature of ~36 °C, while the GBE10-E3 housing reached a temperature of ~34 °C. With a 200 W beam, the GBE02-E3 housing reached a temperature of ~55 °C and the GBE10-E3 housing reached a temperature of 63 °C. For reference, the average internal body temperature is 37 °C. Care should thus be exercised if using the beam expanders for long periods of time with very high-power beams.

    The raw data for these measurements is available by clicking here.

    Damage Threshold Specifications
    Item # Suffix Damage Threshold
    -E3 5 J/cm2 (10.6 µm, 100 ns, 1 Hz, Ø0.478 mm)

    Damage Threshold Data for Thorlabs' Mid-IR Galilean Beam Expanders

    The specifications to the right are measured data for Thorlabs' Mid-IR Galilean Beam Expanders. This is the damage threshold of the AR coating, which limits the power that the beam expander can accept. Note that if these items are being used to reduce the size of a beam, the power at the exit aperture must not exceed this damage threshold.

     

    Laser Induced Damage Threshold Tutorial

    The following is a general overview of how laser induced damage thresholds are measured and how the values may be utilized in determining the appropriateness of an optic for a given application. When choosing optics, it is important to understand the Laser Induced Damage Threshold (LIDT) of the optics being used. The LIDT for an optic greatly depends on the type of laser you are using. Continuous wave (CW) lasers typically cause damage from thermal effects (absorption either in the coating or in the substrate). Pulsed lasers, on the other hand, often strip electrons from the lattice structure of an optic before causing thermal damage. Note that the guideline presented here assumes room temperature operation and optics in new condition (i.e., within scratch-dig spec, surface free of contamination, etc.). Because dust or other particles on the surface of an optic can cause damage at lower thresholds, we recommend keeping surfaces clean and free of debris. For more information on cleaning optics, please see our Optics Cleaning tutorial.

    Testing Method

    Thorlabs' LIDT testing is done in compliance with ISO/DIS 11254 and ISO 21254 specifications.

    First, a low-power/energy beam is directed to the optic under test. The optic is exposed in 10 locations to this laser beam for 30 seconds (CW) or for a number of pulses (pulse repetition frequency specified). After exposure, the optic is examined by a microscope (~100X magnification) for any visible damage. The number of locations that are damaged at a particular power/energy level is recorded. Next, the power/energy is either increased or decreased and the optic is exposed at 10 new locations. This process is repeated until damage is observed. The damage threshold is then assigned to be the highest power/energy that the optic can withstand without causing damage. A histogram such as that below represents the testing of one BB1-E02 mirror.

    LIDT metallic mirror
    The photograph above is a protected aluminum-coated mirror after LIDT testing. In this particular test, it handled 0.43 J/cm2 (1064 nm, 10 ns pulse, 10 Hz, Ø1.000 mm) before damage.
    LIDT BB1-E02
    Example Test Data
    Fluence # of Tested Locations Locations with Damage Locations Without Damage
    1.50 J/cm2 10 0 10
    1.75 J/cm2 10 0 10
    2.00 J/cm2 10 0 10
    2.25 J/cm2 10 1 9
    3.00 J/cm2 10 1 9
    5.00 J/cm2 10 9 1

    According to the test, the damage threshold of the mirror was 2.00 J/cm2 (532 nm, 10 ns pulse, 10 Hz, Ø0.803 mm). Please keep in mind that these tests are performed on clean optics, as dirt and contamination can significantly lower the damage threshold of a component. While the test results are only representative of one coating run, Thorlabs specifies damage threshold values that account for coating variances.

    Continuous Wave and Long-Pulse Lasers

    When an optic is damaged by a continuous wave (CW) laser, it is usually due to the melting of the surface as a result of absorbing the laser's energy or damage to the optical coating (antireflection) [1]. Pulsed lasers with pulse lengths longer than 1 µs can be treated as CW lasers for LIDT discussions.

    When pulse lengths are between 1 ns and 1 µs, laser-induced damage can occur either because of absorption or a dielectric breakdown (therefore, a user must check both CW and pulsed LIDT). Absorption is either due to an intrinsic property of the optic or due to surface irregularities; thus LIDT values are only valid for optics meeting or exceeding the surface quality specifications given by a manufacturer. While many optics can handle high power CW lasers, cemented (e.g., achromatic doublets) or highly absorptive (e.g., ND filters) optics tend to have lower CW damage thresholds. These lower thresholds are due to absorption or scattering in the cement or metal coating.

    Linear Power Density Scaling

    LIDT in linear power density vs. pulse length and spot size. For long pulses to CW, linear power density becomes a constant with spot size. This graph was obtained from [1].

    Intensity Distribution

    Pulsed lasers with high pulse repetition frequencies (PRF) may behave similarly to CW beams. Unfortunately, this is highly dependent on factors such as absorption and thermal diffusivity, so there is no reliable method for determining when a high PRF laser will damage an optic due to thermal effects. For beams with a high PRF both the average and peak powers must be compared to the equivalent CW power. Additionally, for highly transparent materials, there is little to no drop in the LIDT with increasing PRF.

    In order to use the specified CW damage threshold of an optic, it is necessary to know the following:

    1. Wavelength of your laser
    2. Beam diameter of your beam (1/e2)
    3. Approximate intensity profile of your beam (e.g., Gaussian)
    4. Linear power density of your beam (total power divided by 1/e2 beam diameter)

    Thorlabs expresses LIDT for CW lasers as a linear power density measured in W/cm. In this regime, the LIDT given as a linear power density can be applied to any beam diameter; one does not need to compute an adjusted LIDT to adjust for changes in spot size, as demonstrated by the graph to the right. Average linear power density can be calculated using the equation below. 

    The calculation above assumes a uniform beam intensity profile. You must now consider hotspots in the beam or other non-uniform intensity profiles and roughly calculate a maximum power density. For reference, a Gaussian beam typically has a maximum power density that is twice that of the uniform beam (see lower right).

    Now compare the maximum power density to that which is specified as the LIDT for the optic. If the optic was tested at a wavelength other than your operating wavelength, the damage threshold must be scaled appropriately. A good rule of thumb is that the damage threshold has a linear relationship with wavelength such that as you move to shorter wavelengths, the damage threshold decreases (i.e., a LIDT of 10 W/cm at 1310 nm scales to 5 W/cm at 655 nm):

    CW Wavelength Scaling

    While this rule of thumb provides a general trend, it is not a quantitative analysis of LIDT vs wavelength. In CW applications, for instance, damage scales more strongly with absorption in the coating and substrate, which does not necessarily scale well with wavelength. While the above procedure provides a good rule of thumb for LIDT values, please contact Tech Support if your wavelength is different from the specified LIDT wavelength. If your power density is less than the adjusted LIDT of the optic, then the optic should work for your application. 

    Please note that we have a buffer built in between the specified damage thresholds online and the tests which we have done, which accommodates variation between batches. Upon request, we can provide individual test information and a testing certificate. The damage analysis will be carried out on a similar optic (customer's optic will not be damaged). Testing may result in additional costs or lead times. Contact Tech Support for more information.

    Pulsed Lasers

    As previously stated, pulsed lasers typically induce a different type of damage to the optic than CW lasers. Pulsed lasers often do not heat the optic enough to damage it; instead, pulsed lasers produce strong electric fields capable of inducing dielectric breakdown in the material. Unfortunately, it can be very difficult to compare the LIDT specification of an optic to your laser. There are multiple regimes in which a pulsed laser can damage an optic and this is based on the laser's pulse length. The highlighted columns in the table below outline the relevant pulse lengths for our specified LIDT values.

    Pulses shorter than 10-9 s cannot be compared to our specified LIDT values with much reliability. In this ultra-short-pulse regime various mechanics, such as multiphoton-avalanche ionization, take over as the predominate damage mechanism [2]. In contrast, pulses between 10-7 s and 10-4 s may cause damage to an optic either because of dielectric breakdown or thermal effects. This means that both CW and pulsed damage thresholds must be compared to the laser beam to determine whether the optic is suitable for your application.

    Pulse Duration t < 10-9 s 10-9 < t < 10-7 s 10-7 < t < 10-4 s t > 10-4 s
    Damage Mechanism Avalanche Ionization Dielectric Breakdown Dielectric Breakdown or Thermal Thermal
    Relevant Damage Specification No Comparison (See Above) Pulsed Pulsed and CW CW

    When comparing an LIDT specified for a pulsed laser to your laser, it is essential to know the following:

    Energy Density Scaling

    LIDT in energy density vs. pulse length and spot size. For short pulses, energy density becomes a constant with spot size. This graph was obtained from [1].

    1. Wavelength of your laser
    2. Energy density of your beam (total energy divided by 1/e2 area)
    3. Pulse length of your laser
    4. Pulse repetition frequency (prf) of your laser
    5. Beam diameter of your laser (1/e2 )
    6. Approximate intensity profile of your beam (e.g., Gaussian)

    The energy density of your beam should be calculated in terms of J/cm2. The graph to the right shows why expressing the LIDT as an energy density provides the best metric for short pulse sources. In this regime, the LIDT given as an energy density can be applied to any beam diameter; one does not need to compute an adjusted LIDT to adjust for changes in spot size. This calculation assumes a uniform beam intensity profile. You must now adjust this energy density to account for hotspots or other nonuniform intensity profiles and roughly calculate a maximum energy density. For reference a Gaussian beam typically has a maximum energy density that is twice that of the 1/e2 beam.

    Now compare the maximum energy density to that which is specified as the LIDT for the optic. If the optic was tested at a wavelength other than your operating wavelength, the damage threshold must be scaled appropriately [3]. A good rule of thumb is that the damage threshold has an inverse square root relationship with wavelength such that as you move to shorter wavelengths, the damage threshold decreases (i.e., a LIDT of 1 J/cm2 at 1064 nm scales to 0.7 J/cm2 at 532 nm):

    Pulse Wavelength Scaling

    You now have a wavelength-adjusted energy density, which you will use in the following step.

    Beam diameter is also important to know when comparing damage thresholds. While the LIDT, when expressed in units of J/cm², scales independently of spot size; large beam sizes are more likely to illuminate a larger number of defects which can lead to greater variances in the LIDT [4]. For data presented here, a <1 mm beam size was used to measure the LIDT. For beams sizes greater than 5 mm, the LIDT (J/cm2) will not scale independently of beam diameter due to the larger size beam exposing more defects.

    The pulse length must now be compensated for. The longer the pulse duration, the more energy the optic can handle. For pulse widths between 1 - 100 ns, an approximation is as follows:

    Pulse Length Scaling

    Use this formula to calculate the Adjusted LIDT for an optic based on your pulse length. If your maximum energy density is less than this adjusted LIDT maximum energy density, then the optic should be suitable for your application. Keep in mind that this calculation is only used for pulses between 10-9 s and 10-7 s. For pulses between 10-7 s and 10-4 s, the CW LIDT must also be checked before deeming the optic appropriate for your application.

    Please note that we have a buffer built in between the specified damage thresholds online and the tests which we have done, which accommodates variation between batches. Upon request, we can provide individual test information and a testing certificate. Contact Tech Support for more information.


    [1] R. M. Wood, Optics and Laser Tech. 29, 517 (1998).
    [2] Roger M. Wood, Laser-Induced Damage of Optical Materials (Institute of Physics Publishing, Philadelphia, PA, 2003).
    [3] C. W. Carr et al., Phys. Rev. Lett. 91, 127402 (2003).
    [4] N. Bloembergen, Appl. Opt. 12, 661 (1973).

    In order to illustrate the process of determining whether a given laser system will damage an optic, a number of example calculations of laser induced damage threshold are given below. For assistance with performing similar calculations, we provide a spreadsheet calculator that can be downloaded by clicking the button to the right. To use the calculator, enter the specified LIDT value of the optic under consideration and the relevant parameters of your laser system in the green boxes. The spreadsheet will then calculate a linear power density for CW and pulsed systems, as well as an energy density value for pulsed systems. These values are used to calculate adjusted, scaled LIDT values for the optics based on accepted scaling laws. This calculator assumes a Gaussian beam profile, so a correction factor must be introduced for other beam shapes (uniform, etc.). The LIDT scaling laws are determined from empirical relationships; their accuracy is not guaranteed. Remember that absorption by optics or coatings can significantly reduce LIDT in some spectral regions. These LIDT values are not valid for ultrashort pulses less than one nanosecond in duration.

    Intensity Distribution
    A Gaussian beam profile has about twice the maximum intensity of a uniform beam profile.

    CW Laser Example
    Suppose that a CW laser system at 1319 nm produces a 0.5 W Gaussian beam that has a 1/e2 diameter of 10 mm. A naive calculation of the average linear power density of this beam would yield a value of 0.5 W/cm, given by the total power divided by the beam diameter:

    CW Wavelength Scaling

    However, the maximum power density of a Gaussian beam is about twice the maximum power density of a uniform beam, as shown in the graph to the right. Therefore, a more accurate determination of the maximum linear power density of the system is 1 W/cm.

    An AC127-030-C achromatic doublet lens has a specified CW LIDT of 350 W/cm, as tested at 1550 nm. CW damage threshold values typically scale directly with the wavelength of the laser source, so this yields an adjusted LIDT value:

    CW Wavelength Scaling

    The adjusted LIDT value of 350 W/cm x (1319 nm / 1550 nm) = 298 W/cm is significantly higher than the calculated maximum linear power density of the laser system, so it would be safe to use this doublet lens for this application.

    Pulsed Nanosecond Laser Example: Scaling for Different Pulse Durations
    Suppose that a pulsed Nd:YAG laser system is frequency tripled to produce a 10 Hz output, consisting of 2 ns output pulses at 355 nm, each with 1 J of energy, in a Gaussian beam with a 1.9 cm beam diameter (1/e2). The average energy density of each pulse is found by dividing the pulse energy by the beam area:

    Pulse Energy Density

    As described above, the maximum energy density of a Gaussian beam is about twice the average energy density. So, the maximum energy density of this beam is ~0.7 J/cm2.

    The energy density of the beam can be compared to the LIDT values of 1 J/cm2 and 3.5 J/cm2 for a BB1-E01 broadband dielectric mirror and an NB1-K08 Nd:YAG laser line mirror, respectively. Both of these LIDT values, while measured at 355 nm, were determined with a 10 ns pulsed laser at 10 Hz. Therefore, an adjustment must be applied for the shorter pulse duration of the system under consideration. As described on the previous tab, LIDT values in the nanosecond pulse regime scale with the square root of the laser pulse duration:

    Pulse Length Scaling

    This adjustment factor results in LIDT values of 0.45 J/cm2 for the BB1-E01 broadband mirror and 1.6 J/cm2 for the Nd:YAG laser line mirror, which are to be compared with the 0.7 J/cm2 maximum energy density of the beam. While the broadband mirror would likely be damaged by the laser, the more specialized laser line mirror is appropriate for use with this system.

    Pulsed Nanosecond Laser Example: Scaling for Different Wavelengths
    Suppose that a pulsed laser system emits 10 ns pulses at 2.5 Hz, each with 100 mJ of energy at 1064 nm in a 16 mm diameter beam (1/e2) that must be attenuated with a neutral density filter. For a Gaussian output, these specifications result in a maximum energy density of 0.1 J/cm2. The damage threshold of an NDUV10A Ø25 mm, OD 1.0, reflective neutral density filter is 0.05 J/cm2 for 10 ns pulses at 355 nm, while the damage threshold of the similar NE10A absorptive filter is 10 J/cm2 for 10 ns pulses at 532 nm. As described on the previous tab, the LIDT value of an optic scales with the square root of the wavelength in the nanosecond pulse regime:

    Pulse Wavelength Scaling

    This scaling gives adjusted LIDT values of 0.08 J/cm2 for the reflective filter and 14 J/cm2 for the absorptive filter. In this case, the absorptive filter is the best choice in order to avoid optical damage.

    Pulsed Microsecond Laser Example
    Consider a laser system that produces 1 µs pulses, each containing 150 µJ of energy at a repetition rate of 50 kHz, resulting in a relatively high duty cycle of 5%. This system falls somewhere between the regimes of CW and pulsed laser induced damage, and could potentially damage an optic by mechanisms associated with either regime. As a result, both CW and pulsed LIDT values must be compared to the properties of the laser system to ensure safe operation.

    If this relatively long-pulse laser emits a Gaussian 12.7 mm diameter beam (1/e2) at 980 nm, then the resulting output has a linear power density of 5.9 W/cm and an energy density of 1.2 x 10-4 J/cm2 per pulse. This can be compared to the LIDT values for a WPQ10E-980 polymer zero-order quarter-wave plate, which are 5 W/cm for CW radiation at 810 nm and 5 J/cm2 for a 10 ns pulse at 810 nm. As before, the CW LIDT of the optic scales linearly with the laser wavelength, resulting in an adjusted CW value of 6 W/cm at 980 nm. On the other hand, the pulsed LIDT scales with the square root of the laser wavelength and the square root of the pulse duration, resulting in an adjusted value of 55 J/cm2 for a 1 µs pulse at 980 nm. The pulsed LIDT of the optic is significantly greater than the energy density of the laser pulse, so individual pulses will not damage the wave plate. However, the large average linear power density of the laser system may cause thermal damage to the optic, much like a high-power CW beam.

    ESK22 SmartPack Packaging
    Click to Enlarge

    Old Beam Expander Packaging
    ESK22 SmartPack Packaging
    Click to Enlarge

    New Beam Expander Packaging

    Smart Pack Goals

    • Reduce Weight of Packaging
    • Increase Usage of Recyclable Materials
    • Improve Packing Integrity
    • Decrease Shipping Costs

    Thorlabs' Smart Pack Initiative is aimed at minimizing waste while providing adequate protection for our products. By eliminating any unnecessary packaging, implementing design changes, and utilizing eco-friendly materials, this initiative seeks to reduce the environmental impact of our product packaging.

    The new fixed magnification beam expanders packaging is made from over 60% recycled paper products and weighs
    25.44 g less than the old packaging. The transition from foam and non-recycled paper to recycled paper products results in a 68.05% reduction in the amount of CO2 produced per kg of packing materials. All products on this page have transitioned, or are in the process of transitioning to recycled paper.

    As we move through our product line, we will indicate re-engineered, eco-friendly packaging with our Smart Pack logo, which can be seen in the image to the right.


    Posted Comments:
    Nate Hough  (posted 2023-12-01 09:40:31.133)
    Could these beam expanders be made with Si or BaF2 optics and optimized for the 2-5um band? Looks like these are labeled mid-IR but the 7-12um band is usually referred to as long wave-IR.
    fnero  (posted 2023-12-04 04:15:40.0)
    Thank you for your feedback. At the moment, the only beam expanders we have for the the wavelength range 2-5um, are the reflective beam expanders, available here, https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=4089. We have reached out to you to further discuss your application.
    Jungwook Kim  (posted 2022-09-30 14:01:37.697)
    Can you provide the LIDT for CW? We are using 9.6 um CO2 laser.
    jgreschler  (posted 2022-10-17 03:30:11.0)
    Thank you for reaching out to Thorlabs. We do not currently have LIDT data for this product at 9.6um. Additional specs and data can be requested by emailing techsupport@thorlabs.com. I have reached out to you directly to discuss this further.

    Thorlabs offers fixed magnification beam expanders, as well as zoom beam expanders that do not need to be refocused when the magnification is adjusted since the collimation remains constant. The table below provides a direct comparison of the options we offer. Please contact Tech Support if you would like help choosing the best beam expander for your specific application.

    Beam Expander
    Description
    Fixed Magnification UVFS Laser Line,
    Sliding Lens
    Fixed Magnification Achromatic,
    Sliding Lens
    Fixed Magnification Mid-Infrared,
    Sliding Lens
    Expansions Available 2X, 3X, 5X, 10X, 20Xa 2X, 3X, 5X, 10X,
    15X, 20X
    2X, 5X, 10X
    AR Coating Range(s)
    (Item # Suffix)
    240 - 360 nm (-UVB)
    248 - 287 nm (-266)
    325 - 380 nm (-355)
    488 - 580 nm (-532)
    960 - 1064 nm (-1064)
    400 - 650 nm (-A)
    650 - 1050 nm (-B)
    1050 - 1650 nm (-C)
    7 - 12 μm (-E3)
    Mirror Coating (Range) N/A
    Reflectance (per Surface) Rmax < 1.5% (-UVB)
    Ravg < 0.2% (All Others)
    Rmax < 0.5% Ravg < 1.0%
    Max Input Beam Diameter 2X: 8.5 mm
    3X: 9.0 mm
    5X: 4.3 mm
    10X: 2.8 mm
    20X: 2.0 mm
    2X: 8.5 mm
    3X: 9.0 mm
    5X: 5.0 mm
    10X: 3.0 mm
    15X: 2.5 mm
    20X: 2.0 mm
    2X: 9.5 mm
    5X: 6.7 mm
    10X: 3.5 mm
    Wavefront Error <λ/4 (Peak to Valley)
    Surface Quality 10-5 Scratch-Dig 20-10 Scratch-Dig 80-50 Scratch-Dig
    • These 20X beam expanders are only available with V coatings for 355 nm, 532 nm, or 1064 nm.

    Beam Expander
    Description
    Zoom UVFS,
    Sliding Lens
    Zoom Achromatic,
    Sliding Lens
    Reflective Beam Expander
    Fixed Magnification
    Expansions Available 0.5X - 2.5X, 1X - 4X,
    2X - 8X, 4X - 16X
    0.5X - 2.5X, 1X - 4X,
    2X - 8X, 4X - 16X
    2X, 4X, 6X
    AR Coating Range(s)
    (Item # Suffix)
    240 - 360 nm (UVB)
    330 - 370 nm (3)
    495 - 570 nm (2)
    980 - 1130 nm (1)
    400 - 650 nm (A)
    650 - 1050 nm (B)
    1050 - 1650 nm (C)
    N/A
    Mirror Coating (Range) N/A Protected Silver
    (450 nm - 20 μm)
    Reflectance (per Surface) Rmax < 1.5% for (UVB)
    Ravg < 0.2% (All Others)
    Rmax < 0.5% Ravg > 96%
    Max Input Beam Diameter 0.5X - 2.5X: 10.9 to 8.0 mm
    1X - 4X: 10.9 to 8.8 mm
    2X - 8X: 6.0 to 4.4 mm
    4X - 16X: 6.0 to 2.7 mm
    0.5X - 2.5X: 10.9 to 8.0 mm
    1X - 4X: 10.9 to 8.8 mm
    2X - 8X: 6.0 to 4.4 mm
    4X - 16X: 6.0 to 2.7 mm
    3 mm
    Wavefront Error <λ/4 (Peak to Valley) <λ/10a (RMS)
    Surface Quality 10-5 Scratch-Dig 20-10 Scratch-Dig 40-20 Scratch-Dig
    • For a Ø1.5 mm Input Beam at 2X magnification, Ø1.0 mm Input Beam at 4X magnification, or Ø0.5 mm Input Beam at 6X magnification.
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    Mid-IR Beam Expanders, Broadband AR Coated: 7 - 12 µm

    Item # Expansion Max Input
    Beam Diameter
    Diffraction-Limited Input
    Beam Diametera
    Input Thread Output Thread
    (External)
    AR Coating
    Reflectance
    Typical
    Transmission
    Damage
    Thresholdb
    GBE02-E3 2X 9.5 mm 9.5 mm Internal: SM05
    External: SM1
    SM1 Ravg < 1.0%
    Rabs < 2.0%
    for 7 - 12 μm
    94% 5 J/cm2
    (10.6 µm, 100 ns, 1 Hz, Ø0.478 mm)
    GBE05-E3 5X 6.7 mm 5.0 mm M43 x 0.5c
    GBE10-E3 10X 3.5 mm 3.5 mm
    • Maximum input beam diameter for output Peak-to-Valley Wavefront Error (WFE) <λ/4 with refocusing.
    • This is the damage threshold of the AR Coating, which limits the power that the beam expander can accept. Note that if these items are being used to reduce the size of a beam, the power at the exit aperture must not exceed this damage threshold.
    • The SM2A30 thread adapter can be used to integrate these beam expanders with our SM2-Threaded Lens Tubes and 60 mm Cage Components.
    Based on your currency / country selection, your order will ship from Newton, New Jersey  
    +1 Qty Docs Part Number - Universal Price Available
    GBE02-E3 Support Documentation
    GBE02-E32X Mid-IR Galilean Beam Expander, AR Coated: 7 - 12 µm
    $768.64
    Today
    GBE05-E3 Support Documentation
    GBE05-E35X Mid-IR Galilean Beam Expander, AR Coated: 7 - 12 µm
    $966.64
    7-10 Days
    GBE10-E3 Support Documentation
    GBE10-E310X Mid-IR Galilean Beam Expander, AR Coated: 7 - 12 µm
    $1,001.58
    7-10 Days
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    Mounting Accessories

    Several mounting options for the Mid-IR Beam Expanders are provided in the table below. For our complete selection of thread adapters, see our Optical Component Thread Adapters selection guide.

    Item # SM1RC(/M) SM1TC CP36 SM2A21 SM2A30
    Photo
    (Click to Enlarge)
    SM1RC SM1TC CP36 SM2A21 SM2A30
    Application Slip Ring for Post Mounting Clamp for Post Mounting 30 mm Cage Mount for Ø1.2" Housing Mount Beam Expander in Ø2" or
    SM2-Threaded Optic Mounts
    Integrate Beam Expander with
    SM2-Threaded Components
    Compatible MidIR Beam Expanders (Item # Prefix) GBE02
    GBE05
    GBE10
    GBE02
    GBE05
    GBE10
    GBE02
    GBE05a
    GBE10a
    GBE02
    GBE05
    GBE10
    GBE05
    GBE10
    Internal Bore /
    Threads
    Ø1.2" Bore Ø1.2" Bore Ø1.2" Bore Ø1.2" Bore M43 x 0.5 Threads
    External Threads / Outer Diameter - - - SM2 Threads and
    Ø2" Smooth Surface
    SM2 Threads
    Mounting Holes 8-32 (M4) Tap #8 (M4) Counterbore Compatible with
    30 mm Cage Systems
    - -
    • The output of these beam expanders will not fit inside of a 30 mm cage system. The CP36 can be used to mount these beam expanders if they are being used at the termination of a section of cage system, i.e., the cage rods only extend over the Ø1.2" section of the housing. If the entire beam expander needs to be enclosed in the cage system, the SM2A21 adapter can be mounted in an LCP36 cage plate for integration into a 60 mm cage system.
    Based on your currency / country selection, your order will ship from Newton, New Jersey  
    +1 Qty Docs Part Number - Imperial Price Available
    SM1RC Support Documentation
    SM1RCSlip Ring for SM1 Lens Tubes and C-Mount Extension Tubes,
    8-32 Tap
    $27.56
    Today
    +1 Qty Docs Part Number - Universal Price Available
    SM1TC Support Documentation
    SM1TCClamp for SM1 Lens Tubes and C-Mount Extension Tubes
    $50.18
    Today
    CP36 Support Documentation
    CP3630 mm Cage Plate, Ø1.2" Double Bore for SM1 and C-Mount Lens Tubes
    $24.23
    Today
    SM2A21 Support Documentation
    SM2A21Externally SM2-Threaded Mounting Adapter with Ø1.20" (Ø30.5 mm) Bore and 2" Outer Diameter
    $53.75
    Today
    SM2A30 Support Documentation
    SM2A30Adapter with External SM2 Threads and Internal M43 x 0.5 Threads
    $18.18
    Today
    +1 Qty Docs Part Number - Metric Price Available
    SM1RC/M Support Documentation
    SM1RC/MSlip Ring for SM1 Lens Tubes and C-Mount Extension Tubes,
    M4 Tap
    $27.56
    Today