1.Product Descriptions:
| Characteristics: | 490nm Bandpass Filter |
| Type: | Interference Type Filter |
| Central Wavelength(in nm): | 490nm |
| Peak Transmittance(%) : | >85% |
| Full Width at Half Maximum(FWHM): | 35nm |
| Optical Density (OD): | OD2 – OD3 |
| Shape: | Round, Square or customized. |
| Color: | Green |
| Angle of Incidence(AOI): | 0° |
| 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 materials: | Ultra-clear glass,K9,BK7,B270,D2637T, Quartz Glass(Fused Silica) or other specified. |
| Remark: Support customized for wavelength from 200-2500nm. | |
2.Measured Spectral Graph – 490nm bandpass filters:
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| Picture 1: BP490-35nm Spectral Graph |
What is typical application for 490nm narrow bandpass filter?
A 490nm bandpass filter is an optical device that selectively transmits light centered around the 490nm wavelength while blocking light at all other wavelengths. 490nm bandpass filters serve a broad range of applications, including biomedical instruments, environmental monitoring, fluorescence microscopy, and industrial inspection.
What is key parameter when choose for right Narrow bandpass filters?
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, 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): 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 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.
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.
