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646nm Longpass Dichroic Mirror
646nm Longpass Dichroic Mirror is an optical filter designed to transmit wavelength above 646nm and reflect wavelength below 646nm. Coligh manufactures dichroic mirror
It has key features below:
- Cut on wavelength 646nm
- Interference Hard Caoting
- High transmission and high reflection
- Suitable for separating excitation and emission signals of red fluorescent probes (such as Alexa Fluor 647, Cy5)
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Hard-Coated Dielectric 646nm Longpass Beamsplitter Description
646nm Longpass Dichroic Mirror is a high-performance optical filter designed to reflect wavelengths below 646nm and transmit longer wavelengths above this cutoff point. With durable hard-coated dielectric layers, , this mirror delivers excellent spectral separation, high thermal and environmental stability, and minimal autofluorescence.
- Its cut on wavelength is 646nm, Enables precise spectral separation of excitation and emission bands, minimizing overlap.
- High reflectivity >98% for the wavelength nd high transmission>90% for wavelength
- Hard coating interference dielectric design will offer exceptional durability, scratch resistance, and long-term stability
- Substrate fused silica will make the filter with ultra low auto fluorescence, idea for high-resolution imaging systems and fluorescence applications
- Useful in FRET, live-cell imaging, optogenetics, and multichannel fluorescence setups requiring accurate beam routing.
646nm Longpass Dichroic Mirror Technical Datasheet
| Parameter | Specification |
| Product Type | Dichroic Optical Filter / Longpass Beamsplitter |
| Cut On Wavelength | 646nm ± 1 nm |
| Angle of Incidence (AOI) | 45° |
| Reflectance | ≥98% |
| Transmission Range | > 90% average |
| Working Wavelength Rang | 350-800nm |
| 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 |
| Fluorophores | Compatible with Fluorophores Like Cy5, Alexa Fluor 647, Atto 647N, |
646nm Longpass Dichroic Mirror Applications
- Alexa Fluor 647 Signal Capture
STORM imaging requires 640nm laser to activate Alexa Fluor 647 probes, with emission around 670nm. The 646nm longpass mirror reflects the 640nm excitation light while transmitting >650nm fluorescence, preventing excitation light from overwhelming single-molecule localization signals. - APC-Cy7 Fluorescence Detection in Flow Cytometry
APC-Cy7 has an emission peak at 780nm and is excited by a 640nm laser. The 646nm mirror blocks 640nm scattered light and FITC/PE channel crosstalk (500–600nm), ensuring the purity of far-red signals. - Cy5-Labeled Vascular Imaging
In deep tissue imaging, Cy5 emission at 670nm penetrates tissue well but is prone to interference from surface hemoglobin absorption (540–580nm) and excitation light scatter. The 646nm dichroic mirror blocks <640nm noise and only transmits deep tissue signals. - Multicolor Fluorescence Channel Separation
TRITC emits at 580nm and overlaps spectrally with Cy5 emission at 670nm. Traditional 560nm dichroic mirrors cause crosstalk. The 646nm mirror fully reflects TRITC and transmits only the Cy5 signal, enabling dual-channel scanning with minimized crosstalk.
