Product Descriptions:
| Characteristics: | 855nm Bandpass Filter |
| Type: | Interference type Filter |
| Central Wavelength (CWL): | 855+-5nm |
| Full Width at Half Maximum(FWHM): | 25nm |
| Peak Transmittance(%) : | >90% |
| Optical Density (OD): | OD2 |
| Shape: | Round, Square or customized. |
| Color: | Black |
| Surface Quality: | 60/40 scratch-dig |
| Dimension(mm): | Customized, max. 300x300mm |
| Thickness(mm): | 0.21、0.3、0.55、0.7、1.0、1.1、1.5、1.8、2.0、3.0mm…etc. |
| Substrate: | Ultra-clear glass,K9,BK7,B270,D2637T, Quartz Glass(Fused Silica) or other specified. |
| Remark: Support customized for wavelength from 200-2000nm. | |
Measured Spectral Graph – 855nm Bandpass filter:
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| Picture 1: BP855-25nm Spectral Graph measurement |
What is typical application for 855nm Bandpass Filters?
An 855nm bandpass filter is an optical component for transmitting light specifically at a wavelength of 855nm while blocking other wavelengths. So, It finds applications in NIR spectroscopy, OCT, fluorescence imaging, gas sensing, and machine vision.
What is key parameter when choose for suitable Bandpass Filter?
When selecting a Dual Bandpass Filter, normally the following factors need to be taken into consideration：
- Central Wavelength (CWL)：Firstly, CWL is one of key parameter to designate, and it refer to the central wavelength at stable high transmission rate passband.
- Peak or Average Transmittance(in %): typically ≥90%, Higher transmittance might need Anti-reflective(AR) coating.
- Full width at half maximum (FWHM): it refer to the interval between the two wavelength points where the transmittance rate reaches 50%.
- Blocking rate: usually in terms of optical density(OD), OD2-OD3 for standard and higher blocking rate will be OD4-OD6 per requirement.
- Angle of Incidence (AOI): as Interference Filter is angle sensitive, 0° AOI by default, other AOI e.g. 30/45° need to be specified.
- Physical and environmental requirement: Substrate type, dimensions and thickness, surface quality, and environmental durability.
Shenzhen Hengda Liyuan Optoelectronics introduced advanced optical vacuum technology that apply depositing nano-materials through ion-assisted evaporation onto a multilayer hard film in a high vacuum environment which coating layer is firm and has good tightness, and small bandwidth drift. Besides, Liyuan optoelectronics have been focus on optical coating for more than 17 years ,and the company offer one-stop optical filters solution including Narrow Bandpass Filters, IR cut-off Filters, Longpass Filters, Shortpass Filters, Notch Filters, ND filters, Star filters and Optical sapphire block.
Remark：The appearance color of the optical filter is usually determined by the spectral parameters, the interference type filter varies at different angles, and the pictures in this link may have been taken from different angles, so the actual color should be based on the final spectral parameters required！
