Product Descriptions:
| Characteristics: | 820nm Bandpass Filter |
| Type: | Interference type |
| Central Wavelength (CWL): | 820+-5nm |
| Full Width at Half Maximum(FWHM): | 40/45/70nm |
| Peak Transmittance(%) : | >92% |
| Surface Quality: | 60/40 scratch-dig |
| Optical Density (OD): | OD2-OD3 |
| Color: | Black |
| Shape： | Square, Round, Irregular Shape |
| Dimension(mm): | specified** |
| Thickness(mm): | specified** |
| Substrate: | Ultra-clear glass,K9,BK7,B270,D2637T, Quartz Glass(Fused Silica) or other specified |
| Remark： Spectral range:350-1100nm *Customized capability: 380-2500nm, stock for 10nm intervals. **Common for 86x86mm, 80x80mm, other can customized, max. 300x300mm *** Thickness available: 0.21、0.3、0.55、0.7、1.0、1.1、1.5、1.8、2.0、3.0mm…etc. |
Measured Spectral Graph – 820nm Bandpass filter:
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| Picture 1: BP820-40nm Spectral Graph measurement |
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| Picture 2: BP820-45nm Spectral Graph measurement |
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| Picture 4: BP820-70nm Spectral Graph measurement |
What is typical application for 820nm bandpass filters?
An 820nm bandpass filter is a precision optical component that selectively transmits light within a narrow band centered at 820nm in the near-infrared spectrum, while blocking all ultraviolet, visible light and other out-of-band wavelengths. Typical application for 820nm bandpass filter is very broad, include NIR laser systems, spectral analysis and biophoton detection. It also suits industrial photoelectric sensing, medical imaging and machine vision, removing interfering light to improve signal quality and detection accuracy.
What are key parameters when choose for a suitable Bandpass Filter?
When selecting a Narrow Bandpass Filter, normally the following factors need to be taken into consideration：
- Central Wavelength (CWL)：CWL is one of key parameter to designate first, it refer to the central wavelength at stable high transmission rate passband.
- Peak or Average Transmittance: typically ≥90%, Higher transmittance might need Anti-reflective(AR) coating.
- Full width at half maximum (FWHM): FWHM 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 will be OD4-OD6 per requirement.
- Angle of Incidence (AOI): AOI need to be considered 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.
Related products:
https://liyuan-optics.com/855nm-bandpass-filter-855nm-cwl-25nm-fwhm-support-customized/ Shenzhen Hengda Liyuan Optoelectronics introduced advanced optical technology that apply depositing nanomaterials 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. Liyuan optoelectronics have been focus on optical coating for more than 17 years and offer one-stop optical filters solution including Narrow Bandpass Filters, IR cut-off Filters, Longpass & Short Filters, Notch Filters, ND filters, Star filters and Optical sapphire block. Other typical Bandpass filters in stock from Liyuan Optoelectronics include BP810 BP820 BP830 BP840 BP850 BP860 BP870 BP880 BP890 BP…etc.
