Product Descriptions:
| Characteristics: | 840nm Bandpass Filter |
| Type: | Bandpass Filter |
| Central Wavelength (CWL): | 840+-5nm |
| Full Width at Half Maximum(FWHM): | 30/140nm or customized. |
| Peak Transmittance(%) : | BP840-30nm:>85% BP840-140nm:>92% |
| Cut-off depth: | OD2 |
| Shape: | Round, Square or customized. |
| Color: | Black |
| Surface Quality: | 60/40 scratch-dig |
| Dimension(mm): | Common for 86x86mm, 80x80mm, other can 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. | |
Spectral measurement graph examples
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| Example 1: BP840-30nm Spectral Graph measurement |
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| Example 2: BP840-140nm Spectral Graph measurement |
What is typical application for 840nm Bandpass Filters?
An 840nm bandpass filter is an optical component designed to transmit infrared light centered at 840nm wavelength with specified bandwidth while blocking other wavelengths.
Typically, It finds applications in biomedical instrumentation, chemical analysis, and fluorescence detection. Besides, Spectroscopy and imaging systems also incorporate these filters, which transmit near-infrared light and reject other wavelengths, thereby enhancing measurement accuracy.
What are key parameters when choose for a suitable Bandpass Filter?
When selecting a Bandpass Filter, normally the following factors need to be taken into consideration：
- Central Wavelength (CWL)：Firstly,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%, and 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:
850nm Bandpass Filter, 850nm CWL, 25/40/45/55/60/70/140nm FWHM, Support Customized
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.
