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518nm Dichroic Longpass Filter
518nm dichroic longpass filter is designed to reflect light below 518nm and transmit wavelength above 518nm. Coligh manufactures high precision dichroic filters.
It has key features below:
- Cut on wavelength 518nm
- Above 90% in high transmission band
- Above 98% reflection on shorter wavelength
- Hard coating superior durability
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518nm Hard-Coated Dichroic Longpass Filter Description
The 518nm dichroic longpass filter is based on the interference effect of multiple dielectric layers deposited on a fused quartz substrate.
- This 518nm longpass filter is designed for a 45° incident angle and is ideal for applications that require beam splitting or light direction control.
- Below518nm reflectivity>=98%, efficiently reflecting the band below green light. It can efficiently isolate the excitation light and minimize the interference of excitation light with fluorescence detection.
- Above 518nm transmittance>=90% ensures lossless passage of red to near-infrared 550-750nm signals, supports wide-band detection, and improves imaging/detection sensitivity.
- By reflecting excitation light and transmitting fluorescence emission light, high-contrast observation and accurate signal reading are achieved, which is especially suitable for fluorescence microscopy imaging.
- We use fused quartz as the substrate. Fused quartz has very low absorption in the ultraviolet, visible and near-infrared bands, can withstand high temperatures, has a low thermal expansion coefficient, and its optical properties change very little with temperature. In addition, the fused quartz material itself has almost no fluorescence background, making it suitable for fluorescence microscopy and bio-optical applications to avoid signal interference.
518nm Dichroic Longpass Filter Technical Datasheet
| Parameter | Specification |
| Product Type | Dichroic Optical Filter / Longpass Beamsplitter |
| Cut On Wavelength | 518 nm ± 1 nm |
| Angle of Incidence (AOI) | 45° |
| Reflectance | ≥98% |
| Transmission Range | > 90% average |
| Working Wavelength Rang | 350-750nm |
| Coating Type | Hard-coated dielectric multilayer |
| Substrate Material | Fused Silica |
| Surface Quality | 60/40 or better (per MIL-PRF-13830B) |
| Size Options | 15*11*1.0mm, custom sizes available |
| Clear Aperture | > 90% of dimension |
| Thickness | 1.0 mm ± 0.1 mm |
518nm Dichroic Longpass Filter Applications
- Multicolor fluorescence microscopy
Multi-fluorescence markers FITC and Cy3 need to separate the excitation light 488nm, 514nm and the emission light 550nm, 570nm to avoid signal cross-contamination. The 518nm Wavelength-Selective Mirror can be installed in a fluorescence microscope to reflect the excitation light onto the sample, accurately separate the excitation wavelength (<518nm) and the emission wavelength (>518nm), and ensure that the fluorescence signal is not interfered by the excitation light. Significantly improve image contrast and signal-to-noise ratio, and improve weak fluorescence detection capabilities - Laser beam combining and splitting system
Multi-wavelength laser systems need to guide laser beams of different wavelengths to different channels or focus on one point to achieve multi-channel laser excitation or detection. The 518nm Reflective Longpass Filter can reflect blue light and transmit red light to achieve dual-wavelength coaxial output. - Fluorescence quantitative PCR system
During the fluorescence signal acquisition process, it is necessary to eliminate the stray excitation light to obtain accurate fluorescence intensity. The 518nm Cut-On Dichroic Filter is installed in the detection channel to reflect stray excitation light below 518nm and only allow emission fluorescence to pass through. It improves the accuracy, repeatability and sensitivity of quantitative PCR and is suitable for high-throughput detection platforms.
