Product Descriptions:
| Characteristics: | 660nm Narrow Bandpass Filter |
| Type: | Interference type |
| Central Wavelength (CWL): | 440nm |
| Full Width at Half Maximum(FWHM): | 40/60nm or customized. |
| Peak Transmittance(%) : | >90% |
| Surface Quality: | 60/40 scratch-dig |
| Optical Density (OD): | OD2 |
| Color: | Blue |
| Shape： | Round or customized. |
| 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 – 440nm Bandpass filter:
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| Example 1: BP440-40nm Spectral Graph measurement |
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| Example 2: BP440-60nm Spectral Graph measurement |
What is typical application for 440nm Bandpass Filter?
A 440nm bandpass filter is an optical component that selectively transmits blue light centered around the 440nm wavelength while blocking light at all other wavelengths.
Typically application for 440nm Bandpass Filters are very broad, include fluorescence microscopes and biochemical immunoassay equipment, blue-violet spectral analysis instruments, industrial particle detection and optical sensing systems, medical diagnostic optical devices, Light source calibration and environmental optical monitoring.
What are key parameters when choose for a suitable Bandpass Filters?
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:
450nm Bandpass Filter, 450nm CWL, 30/45/50nm 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. The company 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：Because the interference type filter varies its performance at different angles, the spectral parameters usually determine its appearance color; moreover, the pictures in this link may originate from various shooting angles, so the actual color should therefore rely on the final spectral parameters required as the standard.
