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540nm Dichroic Filter
540nm dichroic filter is a optical filter reflect wavelengths shorter than 540nm while transmitting longer. Coligh manufactures dichroic mirrors.
It has key features below:
- Cut on wavelength 540nm
- Above 90% in high transmission band
- Above 98% reflection on shorter wavelength
- Hard coating superior durability
540nm Dichroic Longpass Filter Description
The 540nm dichroic filter achieves high-precision spectral separation at 540nm, transmitting wavelengths below 540nm and reflecting wavelengths above 540nm. It features a steep transition between the transmission and reflection bands, ensuring clear spectral analysis without crosstalk.
- We use ion-assisted deposition (IAD) to coat the optical thin films. This multi-layer hard coating technology enhances the durability and adhesion of the film layers.
- The 540nm dichroic filter operates within the 350–750nm spectral range. The average transmittance in the transmission band is over 90%, and the average reflectance in the reflection band exceeds 98%. High transmission and reflectance significantly improve the system’s signal-to-noise ratio and eliminate interference from stray light.
- This dichroic mirror uses fused silica as the substrate. Fused silica has a near-zero thermal expansion coefficient, making it suitable for high-power or thermally variable environments. It also has an ultra-low autofluorescence background, making it especially suitable for fluorescence imaging and ensuring accurate detection of weak signals.
- We offer a wide range of dichroic filters in stock, from 415nm to 772nm. Inquiries are welcome.
540nm Dichroic Filter Technical Datasheet
| Parameter | Specification |
| Product Type | Dichroic Optical Filter / Longpass Beamsplitter |
| Cut On Wavelength | 540 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 |
540nm Dichroic Filter Applications
- Fluorescence Microscopy
In fluorescence microscopy, the 540nm dichroic mirror is mainly used for fluorescence imaging. It plays a key role in separating the excitation and emission light paths. It transmits the excitation light while reflecting the emission light from the fluorescent sample toward the detector. Therefore, the 540nm dichroic mirror enables efficient and precise separation of excitation and emission light, greatly suppressing background noise and excitation light leakage, and significantly improving image signal-to-noise ratio and contrast. This is essential for detecting weak fluorescence signals, high-resolution imaging, and long-term live cell observation.
- Flow Cytometry
Flow cytometers need to simultaneously detect signals of different colors emitted by multiple fluorescent markers on cells. The 540nm dichroic mirror can be used to precisely separate specific fluorescence channels by reflecting light with wavelengths shorter than 540nm (which may be signals from other channels or scattered light), while transmitting light with wavelengths longer than 540nm. This ensures high-purity separation of fluorescence signals from different channels and reduces crosstalk, making it suitable for immunophenotyping, cell function analysis, and cell sorting.
- Laser Beam Combining and Splitting Systems
In systems that require combining multiple laser beams of different wavelengths or separating specific wavelengths from composite light, highly efficient and low-loss optical components are essential. The 540nm dichroic mirror can separate composite light containing multiple wavelengths or combine 540nm light with others into a single beam. By offering high transmittance/reflectance and low absorption loss, it simplifies optical path design, improves system light efficiency, and reduces heat generation.
- Biochemical Analyzers and Point-of-Care Diagnostic Devices
Many fluorescence- or absorbance-based biochemical assays require precise measurement of light intensity changes at specific wavelengths. The 540nm dichroic mirror can be used in combination with other filters. For example, it may reflect excitation light to the sample cuvette while transmitting the signal light generated after the sample reaction—typically with characteristic emission or absorption near 540nm—to the photodetector. This ensures reliable results in clinical diagnostics and biochemical analysis.
