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Dichroic Beamsplitter (Custom design)
Dichroic beamsplitters transmit light of a certain waveband and reflect its complement. They have a dielectric coating that exploits interference rather than absorption to isolate the spectral bands, resulting in a steep transition between the region of transmission and reflection, but are sensitive to the incident angle.
Dichroic Beamsplitter Cubes
Dichroic beamsplitter cube consists of a pair of precision right-angle prisms cemented together to minimize wavefront distortion. The hypotenuse of one of the prisms is coated with a metal-dielectric hybrid or all dielectric dichroic beamsplitter coating designed to fit the needs of the color combination or color separation. A beam of color light is reflected and its complement is transmitted through the cube. The four external faces are broadband AR coated to reduce surface reflection over the application waveband. We can offer cube sizes of 5.0, 6.35, 10, 12.7, 15, 20, 25.4, 38.1 and 50.8 mm.
Polarizing Dichroic Beamsplitter Cubes
Polarization dichroic beamsplitter cubes transmit a certain color and reflect its complementary color when a light beam is incident upon the outside face. Both the incoming and outgoing beams are s-polarized.
Polarization State Transform
| Incoming Beam |
Outgoing R/T Beams |
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Two s-polarized light beams |

Non-polarizing Dichroic Beamsplitter Cubes
The hypotenuse of one of the prisms is coated with a metal-dielectric hybrid dichroic beamsplitter coating designed to separate a certain wavelength range from another. The beamsplitter has moderate absorption but minimal polarization sensitivity. Cube sizes are available of 5.0, 6.35, 10, 12.7, 15, 20, 25.4, 38.1 and 50.8 mm.

| Incoming Beam |
Outgoing Beams |
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45º linearly polarized, Circularly polarized, Natural light
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Same as incoming light |
Dichroic Edge Pass Beamsplitter Plates
Little or no absorption
Independent of polarization
Edge pass beamsplitter plates are divided into short-pass and long-pass filters according to whether they transmit below or above the transition wavelength. The transition wavelength or cut-on/off wavelength (COWL) is the wavelength at which the transmission is 50% of its peak value.
These filters have a very steep transition between the region of transmission and reflection, much steeper than that of colored glass filters. They have a hard and dielectric filter coating using interference rather than absorption to isolate the spectral bands. Unlike colored glass filters, the center wavelength will shift to shorter wavelengths with an increase in angle of incidence. This can be useful for tilt tuning these filters to the exact wavelength. A certain bandpass filter with excellent performance can be constructed using a combination of a short-pass and a long-pass filter.


| Material: |
BK7 grade A optical glass or fused silica |
| Dimension: |
±0.5 mm |
| Thickness: |
±0.5 mm |
| Wedge: |
3 arc minute |
| Wavefront Distortion: |
1l per inch over the clear aperture |
| Surface Quality: |
80-50 scratch-dig |
| Clear Aperture: |
> 85% of dimension |
| Angle of Incidence: |
±5 |
| Transmission |
> 85%, average |
| Blocking |
< 1%, average |
| Cut-on/Cut-off Wavelength |
< 10 nm |
| Wavelength Shift With Temperature |
< 0.25 nm/°C |
| Temperature Range: |
-50°C to +100°C |
| Damage Threshold |
1kW/cm2 CW & 1 J/cm2 pulsed |
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