Product Descriptions：
| Characteristics: | BP475-65nm bandpass filter |
| Type: | Interference filters |
| Central Wavelength (CWL): | 475nm |
| Full Width at Half Maximum (FWHM): | 65nm |
| Average Transmittance(%): | 90% |
| Optical Density： | OD2 |
| Surface Quality: | 60/40 scratch-dig |
| Color: | Blue |
| Shape | Circular or customized |
| Dimension(mm): | Dia. 23.8mm or customized |
| Thickness: | 1.0mm or customized |
| Substrate: | Ultra-clear glass,K9,BK7,B270,D2637T, Quartz Glass(Fused Silica) or other specified. |
| Remark：Support customized. | |
Spectral measurement graph
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| Picture 1: BP475-65nm bandpass filter Spectral measurement graph |
What is the BP475nm optical bandpass filter?
The BP475 bandpass filter precisely isolates a narrow band of blue light centered at 475 nm. Its primary function is to transmit this specific blue wavelength with high efficiency while blocking all other unwanted light, including UV, other visible colors, and near-infrared (NIR) radiation. The transmittance range depends on the the bandwidth which varies by model, offering options such as narrow 18 nm, 30 nm, or wider 50 nm, 65nm …etc FWHM.
What are key parameters when choose for a suitable Bandpass Filter?
When selecting 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:
480nm Bandpass Filter, 480nm CWL, 40nm 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.
