Broadband Dielectric Beamsplitters

Our Broadband Dielectric Beamsplitters are designed to split or combine laser beams operating in the visible through infrared wavelengths. Split ratio is 50/50 R/T for S-polarized light at 45 degrees incidence. Unwanted interference effects are reduced due to a slightly wedged substrate, and an AR coating on the back surface.

S-polarized beams split 50/50 (R/T)
P-polarized beams split 30/70 (R/T)
AR coated back surface eliminates ghosting
Slight wedge virtually eliminates internal fringes
N-BK7 or UV fused silica substrates
Beamsplit ratio maintained over wide wavelength range

See All Features

Show Filters:

Showing 23 of 23 total products

Compatibility:

Description	Compatibility	Diameter	Wavelength Range	Material	Surface Quality	Avail.	Price
10B20BS.1Broadband Dielectric Beamsplitter, 25.4 mm, N-BK7, 480-700 nm	UNIVERSAL	25.4 mm	480-700 nm	Grade A N-BK7	15-5 scratch-dig		$158
10B20BS.2Broadband Dielectric Beamsplitter, 25.4 mm, N-BK7, 700-950 nm	UNIVERSAL	25.4 mm	700-950 nm	Grade A N-BK7	15-5 scratch-dig		$168
10B20BS.3Broadband Dielectric Beamsplitter, 25.4 mm, N-BK7,1290-1580 nm	UNIVERSAL	25.4 mm	1290-1580 nm	Grade A N-BK7	15-5 scratch-dig		$177
10Q20BS.1Broadband Dielectric Beamsplitter, UVFS, 25.4 mm, λ/10, 480-700 nm	UNIVERSAL	25.4 mm	480-700 nm	UV Grade Fused Silica	15-5 scratch-dig		$184
10Q20BS.2Broadband Dielectric Beamsplitter, UVFS, 25.4 mm, λ/10, 700-950 nm	UNIVERSAL	25.4 mm	700-950 nm	UV Grade Fused Silica	15-5 scratch-dig		$190
10Q20BS.3Broadband Dielectric Beamsplitter, UVFS, 25.4mm, λ/10, 1290-1580 nm	UNIVERSAL	25.4 mm	1290-1580 nm	UV Grade Fused Silica	15-5 scratch-dig		$205
10Q40BS.1Broadband Dielectric Beamsplitter, UVFS, 25.4 mm, λ/20, 480-700 nm	UNIVERSAL	25.4 mm	480-700 nm	UV Grade Fused Silica	10-2 scratch-dig		$760
10Q40BS.2Broadband Dielectric Beamsplitter, UVFS, 25.4 mm, λ/20, 700-950 nm	UNIVERSAL	25.4 mm	700-950 nm	UV Grade Fused Silica	10-2 scratch-dig		$774
10Q40BS.3Broadband Dielectric Beamsplitter, UVFS, 25.4 mm, λ/20, 1290-1580 nm	UNIVERSAL	25.4 mm	1290-1580 nm	UV Grade Fused Silica	10-2 scratch-dig		$702
20B20BS.1Broadband Dielectric Beamsplitter, 50.8 mm, N-BK7, 480-700 nm	UNIVERSAL	50.8 mm	480-700 nm	Grade A N-BK7	15-5 scratch-dig		$260
20B20BS.2Broadband Dielectric Beamsplitter, 50.8 mm, N-BK7, 700-950 nm	UNIVERSAL	50.8 mm	700-950 nm	Grade A N-BK7	15-5 scratch-dig		$315
20B20BS.3Broadband Dielectric Beamsplitter, 50.8 mm, N-BK7,1290-1580 nm	UNIVERSAL	50.8 mm	1290-1580 nm	Grade A N-BK7	15-5 scratch-dig		$313
20Q20BS.1Broadband Dielectric Beamsplitter, UVFS, 50.8 mm, λ/10, 480-700 nm	UNIVERSAL	50.8 mm	480-700 nm	UV Grade Fused Silica	15-5 scratch-dig		$360
20Q20BS.2Broadband Dielectric Beamsplitter, UVFS, 50.8 mm, λ/10, 700-950 nm	UNIVERSAL	50.8 mm	700-950 nm	UV Grade Fused Silica	15-5 scratch-dig		$396
20Q20BS.3Broadband Dielectric Beamsplitter, UVFS, 50.8mm, λ/10, 1290-1580 nm	UNIVERSAL	50.8 mm	1290-1580 nm	UV Grade Fused Silica	15-5 scratch-dig		$395
20Q40BS.2Broadband Dielectric Beamsplitter, UVFS, 50.8 mm, λ/20, 700-950 nm	UNIVERSAL	50.8 mm	700-950 nm	UV Grade Fused Silica	10-2 scratch-dig		$1,007
20Q40BS.3Broadband Dielectric Beamsplitter, UVFS, 50.8mm, λ/20, 1290-1580 nm	UNIVERSAL	50.8 mm	1290-1580 nm	UV Grade Fused Silica	10-2 scratch-dig		$1,024
30Q20BS.1Broadband Dielectric Beamsplitter, UVFS, 76.2 mm, λ/10, 480-700 nm	UNIVERSAL	76.2 mm	480-700 nm	UV Grade Fused Silica	15-5 scratch-dig		$881
30Q20BS.2Broadband Dielectric Beamsplitter, UVFS, 76.2 mm, λ/10, 700-950 nm	UNIVERSAL	76.2 mm	700-950 nm	UV Grade Fused Silica	15-5 scratch-dig		$774
30Q20BS.3Broadband Dielectric Beamsplitter, UVFS, 76.2mm, λ/10, 1290-1580 nm	UNIVERSAL	76.2 mm	1290-1580 nm	UV Grade Fused Silica	15-5 scratch-dig		$906
30Q40BS.1Dielectric Beamsplitter, Fused Silica, 76.2 mm, λ/20, 480-700 nm	UNIVERSAL	76.2 mm	480-700 nm	UV Grade Fused Silica	10-2 scratch-dig		$2,369
30Q40BS.2Dielectric Beamsplitter, Fused Silica, 76.2 mm, λ/20, 700-950 nm	UNIVERSAL	76.2 mm	700-950 nm	UV Grade Fused Silica	10-2 scratch-dig		$2,289
30Q40BS.3Dielectric Beamsplitter, Fused Silica, 76.2 mm, λ/20, 1290-1580 nm	UNIVERSAL	76.2 mm	1290-1580 nm	UV Grade Fused Silica	10-2 scratch-dig	Contact Us	$2,204

Show Less

Specifications

Angle of Incidence
45°
Reflection
R_s = 50 ±5%, R_p ≤R_s
Damage Threshold
500 W/cm² CW, 0.5 J/cm² with 10 nsec pulses, typical
Surface Flatness
λ/10 at 632.8 nm over the clear aperture
Diameter Tolerance
+0/-0.13 mm
Thickness Tolerance
±0.38 mm

Wedge
30 ±15 arc min
Clear Aperture
> central 80% of diameter
Chamfers Angle Tolerance
45° ±15°
Durability
MIL-C-675C, moderate abrasion million cycles
Cleaning
See How to Clean Optics

Features

Polarization Effects

Our beamsplitting optics are designed for splitting or combining laser beams, which commonly have S-polarized output in a typical scientific setup. S-polarization will be equally split with R/T = 50/50 at 45° incidence. P-polarized beams will be split 30/70 (R/T). Unpolarized light will be split 40/60 (R/T) on average.

Three Broadband Dielectric Beamsplitter Coatings

Beamsplitters are available with a wide selection of broadband dielectric coatings on the reflecting surface and matching anti-reflection coatings on the back surface. Each set of coatings is essentially achromatic across a wide spectral band so that a single optic will work for the entire range of a particular tunable laser, for several laser diode wavelengths, or for most visible laser wavelengths. BS.1 covers the 480-700 nm spectral range, BS.2 covers the 700-950 nm spectral range and BS.3 covers the 1290-1580 nm spectral range.

N-BK7 Substrates for VIS and NIR Applications

N-BK7 is an excellent lens material for general use such as most visible and near infrared applications. It is the most common borosilicate crown optical glass, and it provides great performance at a good value. Its high homogeneity, low bubble and inclusion content, and straightforward manufacturability make it a good choice for transmissive optics.

UV Fused Silica for UV & Broadband Applications

UV Grade Fused Silica is synthetic amorphous silicon dioxide of extremely high purity providing maximum transmission from 195 to 2100 nm. This non-crystalline, colorless silica glass combines a very low thermal expansion coefficient with good optical qualities, and excellent transmittance in the ultraviolet region. Transmission and homogeneity exceed those of crystalline quartz without the problems of orientation and temperature instability inherent in the crystalline form. It will not fluoresce under UV light and is resistant to radiation. For high-energy applications, the extreme purity of fused silica eliminates microscopic defect sites that could lead to laser damage.

Slight Wedge Suppresses Unwanted Fringes

Optics with perfectly parallel faces are unsuited for use as reference elements in laser setups as reflections from both surfaces would be collinear resulting in undesired large period fringes. Introduction of a slight wedge causes unwanted reflections from the second surface to be deflected from the optical path. An arrow on the side points to the non-wedged side (S1) of the beamsplitter, where has the BS.x beamsplitter coating.

AR Coated Back Surfaces

An antireflection coating NC.x is applied on the back surface to minimize ghost reflections. Three broadband AR coatings are offered and optimized for 45° angle of incidence beams with <0.75% reflectance. NC.1 covers the 440-700 nm spectral range, NC.2 covers the 660-1000 nm spectral range and NC.3 covers the 1010-1550 nm spectral range.

Resources

Selection Guides

Beamsplitting Mounts Guide

Broadband Dielectric Beamsplitters

Broadband Dielectric Beamsplitters

Specifications

Features

Polarization Effects

Three Broadband Dielectric Beamsplitter Coatings

N-BK7 Substrates for VIS and NIR Applications

UV Fused Silica for UV & Broadband Applications

Slight Wedge Suppresses Unwanted Fringes

AR Coated Back Surfaces

Resources

Selection Guides

Related Products

Broadband Non-Polarizing Cube Beamsplitters