Cube Beamsplitter Diagram (Coating and Cement Layer Not to Scale)

Features

5 mm, 10 mm, 1/2" (12.7 mm), 20 mm, and 1" (25.4 mm) Cubes
4 Wavelength Ranges Available:

420 - 680 nm
620 - 1000 nm
900 - 1300 nm
1200 - 1600 nm

Extinction Ratio

T_P:T_S > 1000:1

Thorlabs' polarizing beamsplitting cubes are offered in 5 sizes and with 4 ranges of beamsplitting coatings. These cubes separate the S and P polarization components by reflecting the S component at the dielectric beamsplitter coating, while allowing the P component to pass. For the highest polarization extinction ratio, use the transmitted beam, which offers an extinction ratio of T_P:T_S > 1000:1. As a guideline, the reflected beam will have an extinction ratio of roughly 100:1.

Thorlabs offers polarizing beamsplitter cubes in 5 mm, 10 mm, 1/2" (12.7 mm), 20 mm, and 1" (25.4 mm) sizes. These cubes are made from N-SF1 and are offered in four different coatings to cover the following wavelength ranges: 420 - 680 nm, 620 - 1000 nm, 900 - 1300 nm, and 1200 - 1600 nm. Please see the Specs tab for more information on each cube including its damage threshold, or see the Graphs tab for S and P polarization transmission graphs.

The dielectric beamsplitting coating is applied to the hypotenuse of one of the two prisms that make up the cube. Then, cement is used to bind the two prism halves together (refer to the diagram to the right). Light can be input into any of the polished faces to separate the s- and p-polarizations. However, for best performance, the light should enter through one of the entrance faces of the coated prism, which are indicated by a dot on all sizes except the 1" cubes. The 1" cubes are engraved with arrows indicating the direction of light propagation.

Custom beamsplitter cubes can be ordered by contacting Technical Support.

Coating Range	Damage Threshold
420 - 680 nm	2 J/cm² at 532 nm, 10 ns, 10 Hz, Ø0.803 mm
620 - 1000 nm	2 J/cm² at 810 nm, 10 ns, 10 Hz, Ø0.166 mm
900 - 1300 nm	2 J/cm² at 1064 nm, 10 ns, 10 Hz, Ø0.484 mm
1200 - 1600 nm	5 J/cm² at 1542 nm, 10 ns, 10 Hz, Ø0.181 mm

Beamsplitter Cube Size	5 mm Cube	10 mm Cube	12.7 mm Cube	20 mm Cube	25.4 mm Cube
Coating Range: 420 - 680 nm	PBS051	PBS101	PBS121	PBS201	PBS251
Coating Range: 620 - 1000 nm	PBS052	PBS102	PBS122	PBS202	PBS252
Coating Range: 900 - 1300 nm	PBS053	PBS103	PBS123	PBS203	PBS253
Coating Range: 1200 - 1600 nm	PBS054	PBS104	PBS124	PBS204	PBS254
AR-Coating Reflection	R_avg < 0.5% @ 0° AOI
Dimensional Tolerance	±0.2 mm
Material	N-SF1
Extinction Ratio	Tp:Ts >1,000:1
Transmission Efficiency*	Tp > 90%
Reflection Efficiency*	Rs > 99.5%
Transmitted Beam Deviation	<5 arcmin
Reflected Beam Deviation	90° ± 5 arcmin
Clear Aperture	>70% of Dimension	>80% of Dimension
Surface Flatness	λ/10 @ 633 nm
Wavefront Distortion**	<λ/4 @ 633 nm
Surface Quality	40-20 Scratch-Dig

*Transmission and reflection data is based on that of the beamsplitter coating and does not account for the BBAR surface coating.
**Wavefront distortion is for both transmitted and reflected beams.

Legend for Beam Diagrams

Reflected Beam:

Transmitted Beam:

Beamsplitter Selection Guide

Thorlabs offers five main types of beamsplitters: Pellicle, Cube, Plate, Economy, and Polka Dot. Each type has distinct advantages and disadvantages.

Pellicle Beamsplitters - Pellicle beamsplitters are the best choice when dispersion must be kept to a minimum. They virtually eliminate multiple reflections commonly associated with thicker glass beamsplitters, thus preventing ghosting. In addition, unlike plate beamsplitters, there is a negligible effect on the propagation axis of the transmitted beam with respect to the incident beam.

Pellicle beamsplitters have two disadvantages: They exhibit sinusodial oscillations in the splitting ratio as a function of wavelength, due to thin film interference effects. Click Here for more details. They are also extremely delicate. Since they are fabricated by stretching a nitrocellulose membrane over a flat metal frame, the beamsplitter cannot be touched without destroying the optic. Thorlabs offers pellicle beamsplitters mounted in metal rings for use in kinematic mounts as well as cage cube mounted pellicles.

Beamsplitting Cubes
Thorlabs’ beamsplitter cubes are composed of two right-angled prisms. A dielectric coating, which is capable of reflecting and transmitting a portion of the incident beam, is applied to the hypotenuse surface. Since there is only one reflecting surface, this design inherently avoids ghost images, which sometimes occur with plate-type beamsplitters. Antireflection coatings are available on the entrance and exit faces of certain models to minimize back reflections. As well as providing a cost-effective solution, another advantage of the beamsplitting cube is the minimal shift it causes to the path of the transmitted beam. Thorlabs offers both polarizing and nonpolarizing beamsplitting cubes, in mounted and unmounted configurations, the former being compatible with our 30 mm cage systems.

Polarizing Beamsplitting Cubes - Thorlabs’ polarizing beamsplitter cubes split randomly polarized beams into two orthogonal, linearly polarized components (S and P), as shown in the diagram to the right. S-polarized light is reflected at a 90° angle with respect to the incident beam while P-polarized light is transmitted. Polarizing beamsplitting cubes are useful in applications where the two polarization components are to be analyzed or used simultaneously. Thorlabs offers mounted and unmounted polarizing beamsplitter cubes.

Nonpolarizing Beamsplitting Cubes - These cubes provide a 50:50 splitting ratio that is nearly independent of the polarization of the incident light. The low polarization dependence of the metallic-dielectric coating allows the transmission and reflection for S- and P-polarization states to be within 10% of each other. These beamsplitters are particularly useful with randomly polarized lasers and are specifically designed for applications in which polarization effects must be minimized. Thorlabs offers mounted and unmounted beamsplitter cubes.

Plate Beamsplitters - Thorlabs' plate beamsplitters are optimized for an incidence angle of 45° and feature a dielectric coating on the front surface for long-term stability. To help reduce unwanted interference effects (e.g., ghost images) caused by the interaction of light reflected from the front and back surfaces of the optic, a wedge has been added to these beamsplitters. Dispersion, ghosting, and shifting of the beam may all be potential problems, however. These are the best choice for a general-purpose beamsplitter. Thorlabs offers both polarizing and nonpolarizing plate beamsplitters.

Economy Beamsplitters - These are the most cost effective of all the beamsplitter types. Thorlabs' economy beamsplitters, which have an exposed oxide coating on one side and are uncoated on the other side, are designed to have either a 50:50 or 30:70 splitting ratio throughout the visible spectrum (450 - 650 nm) when used with unpolarized light incident at 45°.

Please note that the Fresnel reflections off of the uncoated back surface of these economy beamsplitters can lead to interference effects in the reflected beam. For applications sensitive to these effects, consider using a beamsplitting cube or a pellicle beamsplitter.

Polka Dot Beamsplitters - This type of beamsplitter consists of a glass substrate with a vacuum-deposited reflective coating that is applied over an array of apertures, giving the beamsplitter a "polka dot" appearance. Half of the incident beam is reflected from the coating, and half of the beam is transmitted through the uncoated portion of the substrate.

Polka Dot Beamsplitter

Polka dot beamsplitters are useful over a wide wavelength range and are negligibly angle sensitive, which makes them ideal for splitting the energy emitted from a radiant source. These are not recommended for imaging applications, as the polka dot pattern will affect the image.

Laser Induced Damage Threshold Tutorial

This tutorial 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.).

Testing Method

Thorlabs' LIDT testing is done in compliance with ISO/DIS11254 specifications. A standard 1-on-1 testing regime is performed to test the damage threshold.

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.

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 a set duration of time (CW) or number of pulses (prf 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.

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 it is only representative of one coating run and that Thorlabs' specified damage thresholds 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. Additionally, when pulse lengths are between 1 ns and 1 µs, LIDT can occur either because of absorption or a dielectric breakdown (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].

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 large 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:

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

The power density of your beam should be calculated in terms of W/cm. The graph to the right shows why the linear power density provides the best metric for long pulse and CW sources. Under these conditions, linear power density scales independently of spot size; 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 consider hotspots in the beam or other nonuniform 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 1/e² 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). 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 pulse lengths that our specified LIDT values are relevant for.

Pulses shorter than 10^-11 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^-9 s and 10^-6 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^-11 s	10^-11 < t < 10^-9 s	10^-9 < t < 10^-6 s	t > 10^-6 s
Damage Mechanism	Avalanche Ionization	Dielectric Breakdown	Dielectric Breakdown or Thermal	Thermal
Relevant Damage Specification	N/A	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].

Wavelength of your laser
Energy density of your beam (total energy divided by 1/e² area)
Pulse length of your laser
Pulse repetition frequency (prf) of your laser
Beam diameter of your laser (1/e² )
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 the energy density provides the best metric for short pulse sources. Under these conditions, energy density scales independently of spot size, 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 power 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^-11 s and 10^-9 s. For pulses between 10^-9 s and 10^-6 s, the CW LIDT must also be checked before deeming the optic appropriate for your application.

[1] R. M. Wood, Optics and Laser Tech. 29, 517 (1997).
[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).

Please Give Us Your Feedback

Email		Feedback On
(Optional)
Contact Me:
Your email address will NOT be displayed.

Please type the following key into the field to submit this form:

Click Here if you can not read the security code.
This code is to prevent automated spamming of our site
Thank you for your understanding.

Would this product be useful to you? Little Use 1 2 3 4Very Useful

Enter Comments Below:

Characters remaining 8000

Posted Comments:

Poster: jlow

Posted Date: 2012-08-08 16:50:00.0

Response from Jeremy at Thorlabs: The difference between the beamsplitters for different wavelength ranges are mainly the AR coating and the beamsplitter coating. The performance for out-of-band wavelength cannot be guaranteed.

Poster: dominic.siriani

Posted Date: 2012-08-08 09:09:50.0

Is the difference between the wavelength ranges on the polarizing beam splitters only the AR coatings on the cube faces? If the 1200-1600 nm splitter were used at ~900 nm, would the transmission extinction ratio still be Tp:Ts > 1000:1?

Poster: tcohen

Posted Date: 2012-07-03 10:37:00.0

Response from Tim at Thorlabs: Thank you for your inquiry. The design wavelength of the PBS051 is 420nm-680nm. Even with an AR coating of 400nm-700nm, the beamsplitter coating would be out of the specified band. To change the design wavelength would involve creating a custom coating, which would include engineering costs and coating production costs. We offer N-BK7, UVFS, CAF2, ZnSe and Ge right angle prisms. I would like to discuss with you the requirements of your system to provide the best options for your application and I will contact you directly to continue this conversation.

Poster: joekkrause

Posted Date: 2012-06-28 23:39:17.0

How much would it cost for you to make a custom cube of N-SF1 with an AR coating for the 400-700 nm range? Also do you offer any right angle prisms made of N-SF1?

Poster: tcohen

Posted Date: 2012-05-16 16:43:00.0

Response from Tim at Thorlabs: Thank you for your feedback! The wavefront distortion is for both the transmitted and reflected beam. We will update our web presentation with this information.

Poster: ahambi

Posted Date: 2012-05-15 03:51:16.0

Is the wavefront distortion $ \lambda/4 $ also for the reflected beam?

Poster: tcohen

Posted Date: 2012-03-01 10:54:00.0

Response from Tim at Thorlabs: Thank you for your feedback on the PBS251. It is difficult to produce exact damage thresholds because of the many variables involved. For CW, usually damage occurs first in the substrate. However, surface irregularities in the optic can also play a role. The intensity profile of your beam will also have an influence on a CW LIDT. As an estimate, we advise not using over 13W/cm^2 CW for this product. However, because LIDT decreases with an increase in frequency, the threshold will be lower for your lower wavelength. I have contacted you directly to find out more information on your setup.

Poster: utsavdeepak.dave

Posted Date: 2012-02-29 09:55:44.0

Hi, I would like to know the damage threshold for the PBS251 product used with blue light (464 nm, CW).

Poster: bdada

Posted Date: 2011-10-06 20:21:00.0

Response from Buki at Thorlabs: Thank you for your feedback. What you may be experiencing is the magneto optical Kerr effect - where the polarization of light changes when it interacts with magnetized media. We think the coating and not the material is what is being magnetized and causing the reflected/transmitted beams to be altered. This magnetization will change as the external magnetic field changes, explaining why the unbalance changes at the same frequency as the rotation of the magnetic field. Please contact TechSupport@thorlabs.com if you want to discuss this further.

Poster: nmandal

Posted Date: 2011-09-28 15:56:42.0

Should the intensities of the two beams coming out of the PBS change in presence of magnetic field? I balance the two beams coming out of the PBS and bring a rotating magnetic field closer to the PBS and I see that the beams are not balanced anymore and the unbalance has the same frequency as the magnetic field. I know the PBS contains SF2 which is polar, could this be the cause or something else.

Poster: jjurado

Posted Date: 2011-06-22 12:50:00.0

Response from Javier at Thorlabs to Mikhail.Levin: Thank you very much for contacting us with your request. We currently do not have information regarding the dependence of the extinction ratio upon the angle of incidence for these polarizing beamsplitters. However, as a guideline, increasing the AOI beyond +/- 2 degrees from the normal of the front surface of the PBS will most likely negatively affect the resultant extinction ratio between the s and p polarizations. I will contact you directly for further support.

Poster: Mikhail.Levin

Posted Date: 2011-06-21 16:00:08.0

Please inform about the angular sensitivity of your product Other words: show the andle( +/- N degrees) in which the extinction parameter (~30dB) is valid Customer Email: Mikhail.Levin@amo.abbott.com This customer would like to be contacted.

Poster: jjurado

Posted Date: 2011-03-18 11:14:00.0

Response from Javier at Thorlabs to drdougsnyder: Thank you for contacting us with your inquiry. Intrinsic variations in the beamsplitter coating result in different retardance values for both s and p components. For the passing beam (this would be Tp, and Rs), you can expect a retardance on the order of 0.01 waves (worst case), and 0.00 waves in the best case. For the rejected beam (Ts and Rp), the phase change can range from 0.00 to 0.125 waves.

Poster:

Posted Date: 2011-03-15 16:21:10.0

What is the refracted index of SF2 at 1064nm? We inted to tilt the beam splitter a little bit and Id like to compute the lateral displacement of the beam. Thank you

Poster: jjurado

Posted Date: 2011-03-15 11:55:00.0

Response from Javier at Thorlabs to last poster: Thank you for submitting your inquiry. The refractive index of SF2 at 1064 nm is 1.62758. Please contact us at techsupport@thorlabs.com if you have any further questions.

Poster: drdougsnyder

Posted Date: 2011-03-09 13:52:35.0

I did not see any information regarding phase change to s and p components due to interaction of light with polarizing beamsplitter cube. You may want to add that information, and I would not mind knowing it.

Poster: christian.roedel

Posted Date: 2011-03-03 13:34:55.0

Dear Sir or Madam, we would like to use polarizing beamsplitters in our high intensity laser. For this purpose we need an excellent AR coating in the cube sides to improve our contrast. I would like to purchase several beamsplitters without the AR coating to see if this has any effect. Would it be possible to buy polarizing beamsplitter cubes without any AR coating? Thanks in advance Sincerely, Christian Rödel

Poster: jjurado

Posted Date: 2011-03-03 10:31:00.0

Response from Javier at Thorlabs to Christian Roedel: Thank you for contacting us with your request. Although is is unlikely that the AR coating on the cubes will considerably affect contrast, we can certainly offer these polarizing cubes uncoated. Keep in mind, however, that the cement used to bond the two prisms together limits the damage threshold of the cube to ~2J/cm^2 (810nm, 10Hz PRF, 10ns pulse width).

Poster: jjurado

Posted Date: 2011-02-07 18:01:00.0

Response from Javier at Thorlabs to Tmel630: Thank you very much for contacting us with your request. Our beamsplitters are comprised of two separate prisms. We apply a dielectric coating to the hypotenuse side of one of the two prisms, and then we use cememt to bond the two prisms together. In order to achieve the desired 50:50 split ratio, it is recommended for the light to enter through one of the faces of the coated prism, which is indicated by a dot. We have updated our Overview Tab with this information.

Poster: Tmel630

Posted Date: 2011-02-04 23:18:42.0

Which face is the input face?

Poster: Thorlabs

Posted Date: 2010-09-13 16:00:38.0

Response from Javier at Thorlabs to Luis: the recommend maximum energy density for the polarizing beamsplitters coated for 1200-1600 nm (PBS054, PBS104, PBS204, and PBS254) is 5 J/cm^2 (tested at 1542 nm, 10 ns pulse). We currently do not have CW damage threshold information for these cubes.

Poster: luis.dussan

Posted Date: 2010-09-13 14:15:17.0

what is the damage threshold for the 1550 wavelength for cw and fluence.

Poster: Thorlabs

Posted Date: 2010-09-10 17:18:24.0

Response from Javier at Thorlabs to Melanie: The wavefront distortion will not vary with size. All of our PBS series beamsplitters have a wavefront distorion spec of < lambda/4 at 633 nm.

Poster: melanieadams

Posted Date: 2010-09-09 15:11:48.0

I like the idea of mounting the PBS in a cube, but notice you only do these for a 1" PBS cube. I have a small beam ~ 2 mm across. How will the wavefront distortion across my beam, vary with the size of the PBS ? Is it better or worse with a larger PBS ? thanks, Melanie

Poster:

Posted Date: 2010-08-10 18:23:31.0

Can I cascade two PBSs to get a higher extinction ratio? (>1000:1)

Poster: vladimirlee

Posted Date: 2010-08-10 15:46:35.0

Does the extinction ratio of the transmitted beam depend on the input polarization? It seems to me that this PBS yields very bad polarization(low extinction ratio) if the input polarization is almost horizontal.

Poster:

Posted Date: 2010-06-01 18:57:56.0

Response from Javier at Thorlabs to guille2306: we do not offer any solutions at the moment. However, we are currently evaluating the possibility of expanding the coating into the UV range. I can keep you updated on the progress of this project. Also, we can discuss your application internally in case you have any additional questions.

Poster: guille2306

Posted Date: 2010-06-01 17:41:27.0

I would be interested in this product, but for the UV range (roughly 230-370nm). Do you have something along this line?

Poster: jens

Posted Date: 2010-03-29 12:55:39.0

A reply from Jens at Thorlabs to Vladimir: yes, the beamsplitter coating is the reason for the lower extinction ratio of the reflected beam. A dielectric coating is used for these cubes.

Poster: vladimirlee

Posted Date: 2010-03-28 19:21:25.0

As a follow-up question regarding the extinction ratio: what makes the reflected beam having a lower extinction ratio than the transmitted beam? Is it the beamsplitting coating that makes this difference? And what kind of beamsplitting coating is used in the cubes? Appreciate for your help.

Poster: Adam

Posted Date: 2010-03-17 18:07:38.0

A response from Adam at Thorlabs to jwoillez: We do have a %T curve and will send this data out to you. Please note that any behaviors outside the designated coating range will vary with every coating run. One run may provide a %T for the P polarization of 65%, while another run may provide a T% for P polarization of 75%. The %T is only optomized for the designated coating range of each product.

Poster: jwoillez

Posted Date: 2010-03-16 21:36:40.0

What is the behavior of at 600~700 nm of the 900-1300 nm polarizing beamsplitter cube? Practically I would like to combine a 1319 nm p polarization with a red laser (tbd 633, 658, or 690) that would be reflected off the cube. If you had a %T curve for p and s polarizations extending to the visible for the 900-1300 nm, that would help.

Poster: apalmentieri

Posted Date: 2010-03-11 13:37:28.0

A response from Adam at Thorlabs to vladimirlee: The extinction ratio for the reflected beam is not the same as the transmitted extinction ratio of 1000:1. The reflected beams extinction ratio is 100:1. If you need higher purity polarization, we would suggest using the transmitted beam.

Poster: vladimirlee

Posted Date: 2010-03-10 16:20:12.0

I wonder whether the extinction ratio is also 1000 to 1 for Ts:Tp for reflected beam? In other words, which beam (reflected or transmitted) do you think should be used for having higher purity polarization? Thanks.

Poster: apalmentieri

Posted Date: 2010-03-01 17:09:06.0

A response from Adam at Thorlabs: We have not yet sent this optic our for damage threshold testing. We will be sending this optic out in the near future and hope to have more information then. In the meantime, I did not see any contact information. If you could, please send us your information to techsupport@thorlabs.com so we can respond direclty to you when we get the information. The information will also be added to the website, but we would like to ensure you get a proper response.

Poster:

Posted Date: 2010-03-01 14:21:58.0

Has the damage threshold data come back yet? If you were to provide this data, I could purchase this product immediately.

Poster: apalmentieri

Posted Date: 2009-11-20 11:09:53.0

A response from Adam at Thorlabs: The cement used is the epoxy Norland 61. Unfortunately, we do not have damage threshold information for this cement.

Poster: apalmentieri

Posted Date: 2009-11-20 10:06:37.0

A response from Adam at Thorlabs: Currently, we do not have a specification on how the separation ratio will change with incident angle. Please note we are looking into this. We also do not have an exact fs damage threshold for the beamsplitters, but we do know that the cement is the limiting factor. I am currently looking into the cement material.

Poster: tiwari.dhir

Posted Date: 2009-11-19 15:32:43.0

Is there any angle of incidence dependence on seperation ratio of polarizations? I would like to know about power ratings for e.g. for pulsed laser (any standard like 1064 nm @ frequency) and continuous laser. Or what kind of cementing material is used it these polarizing beam splitters. I am interested in using it with 1050 nm Femtosecond laser. Dhirendra

Poster: herman

Posted Date: 2009-11-17 21:40:36.0

What is an angular dependence of the polarization ratio? Thanks, Petr H.

Poster: jens

Posted Date: 2009-06-11 16:17:00.0

A reply from Jens at Thorlabs: the item has not specifically designed for femtosecond lasers, so I currently do not have for example dispersion data for the product. There is no inherent feature which would prevent using this item with femtosecond lasers. I would suggest to go ahead and test the device in your setup. Certainly we could take the item back if any unforseen effect prevents you from using the item.

Poster: Dgmoses

Posted Date: 2009-06-11 16:12:02.0

Are there any special issues with this product and use of ultrashort laser pulses.

Poster: ghegenbart

Posted Date: 2008-12-02 04:02:12.0

Response from Gerald (Tech Support Thorlabs Germany): Thank you very much for your interest in our polarizing beam splitters. The product PBS3 is specifically desigend for application in the telecom wavelength range from about 1525 to 1610 nm. It comes with an AR coating for these wavelengths. Using it for the visible part of the spectrum is not possible. We do not offer other polarizing beam splitters yet, but we will introduce them shortly. The family will consist of products covering 4 different wavelength ranges, one of it being 420 to 680 nm. Sizes range from 5 to 25.4 mm. The products are planned to be released by mid to end of January 2009 and will be featured on our web site as soon as they are available. You may also use our RSS feeds service to get notified when the products are introduced.

Poster: patrickm

Posted Date: 2008-12-01 14:53:42.0

To what extent is this product designed for 1525-1610nm. Is there an antireflection coating? I would need a polarizing beam splitter for an application at 532nm - would PBS3 also work at this wavelength? Do you have polarizing beam splitters (with AR coating) specifically designed for visible wave lengths? Best wishes, Patrick Maletinsky

Poster: Laurie

Posted Date: 2008-10-03 09:09:21.0

Response from Laurie at Thorlabs to ADudley: Thank you for your interest in our polarizing beamsplitters. Currently, we cannot provide custom beamsplitters due to the expense of the coating. However, if size is not of primary concern, we are currently in the process of fabricating a 10 mm polarizing beamsplitter for the 400 - 700 nm range. If you are just looking to split the S and P states of light, you may want to try a glan laser polarizer. These can be found on the following website: http://www.thorlabs.com/NewGroupPage9.cfm?ObjectGroup_ID=815&pn=GL5-A&CFID=24982801&CFTOKEN=29910522. However, these do not work as well as the PBS3, and you may receive some wavefront errors from the extraordinary ray, as this side does not have a good polish. If we can be of further assistance, please let us know.

Poster: ADudley

Posted Date: 2008-10-02 03:41:49.0

I am interested in this product, but for the visible wavelength (400-700nm). How do I go about ordering it? And what is an estimated cost for it? As well as delivery time? I am based in South Africa.

Click on any phrase below to search our site using our new Search Engine:

1 1/2"beamsplitters 10 10mm 12.7 12.7mm 20 20mm 25.4 25.4mm 5 5mm BD27 beam Beam splitters beamsplitter beamsplitter cube beamsplitters cube cube mount dichroic cube laser beam splitter linear polarizer nir linear polarizer polarization beam splitter polarization cube polarizers polarizing polarizing beamsplitting cube polarizing cube splitter

View All »Matching Part Numbers

Polarizing Beamsplitter Cubes

Features

Legend for Beam Diagrams

Beamsplitter Selection Guide

Laser Induced Damage Threshold Tutorial

Testing Method

Continuous Wave and Long-Pulse Lasers

Pulsed Lasers