Product Descriptions:
| Characteristics: | 770nm Bandpass Filter |
| Type: | Interference type |
| Central Wavelength (CWL): | 770nm |
| Full Width at Half Maximum(FWHM): | 40nm |
| Peak Transmittance(%) : | >92% |
| Optical Density (OD): | OD2 |
| Shape: | Customized. |
| Color: | Silver |
| Surface Quality: | 60/40 |
| 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. | |
2.Measured Spectral Graph – 770nm Bandpass filter:
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| Picture 1: BP770-40nm +AR Bandpass Filters_Spectral Graph measurement |
What is typical application for 770nm Bandpass Filters?
A 770nm bandpass filter is an optical components designed to selectively transmit a narrow range of near infrared light centered at 770nm while blocking light at all other wavelengths.
A 770nm bandpass filter is widely used in near-infrared spectroscopy and biomedical instrumentation to isolate specific NIR signals for fluorescence and immunoassay applications.
Besides, It also plays a critical role in laser-based systems, such as Raman spectroscopy and laser diode cleanup, by effectively separating the target wavelength from background light and other laser lines.
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)：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.
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.
