1.Product Descriptions:
| Characteristics: | 408nm Longpass filters |
| Type: | Interference type |
| Central Wavelength (CWL): | 408+-5nm |
| Average Transmittance: | >95% |
| Cut-off depth: | OD2-OD3 |
| Surface Quality: | 60/40 scratch-dig |
| Color: | Transparence |
| Shape: | Round, Square, Custom Shape |
| Dimension: | Specified |
| Thickness: | Specified |
| Substrate: | Ultra-clear glass,K9,BK7,B270,D2637T, Quartz Glass(Fused Silica) or other specified |
| Remark: Spectral range:200-1100nm
*Customized capability: 380-2500nm, stock for 10nm intervals.
**Common for 86x86mm, 80x80mm, other can customized, max. 300x300mm
*** Thickness available: 0.21、0.3、0.55、0.7、1.0、1.1、1.5、1.8、2.0、3.0mm, etc. |
2. Measured Spectral curve
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Picture 1: LP408nm Spectral Curve |
3.What is typical application for 408nm longpass filter?
A 408 nm longpass filter is a precision optical component. It allows light with wavelengths longer than 408nm to pass through, while blocking all shorter ultraviolet and short-wavelength visible light. The 408nm longpass filter finds applications in fluorescence microscopy, UV laser equipment, biochemical analysis and spectral measurement instruments. It filters out short-wavelength stray light to optimize signal quality and detection precision.
4.What is key parameter when choose for right Longpass Filter?
When selecting a Longpass Filter, normally the following factors need to be taken into consideration：
- Cut-Off Wavelength: it is one of the most important parameters, typically defined as the wavelength transmittance at 50% .
- Average or Peak transmittance: usually average transmittance ≥90%, higher transmittance e.g. 92% or 95% on average or specific single point need to definite and communicate with manufacturer, higher transmittance need to additional AR coating.
- Blocking rate: usually expressed 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 consider 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.
other Longpass filters in stock from Liyuan Optoelectronics: LP430 LP500 LP560 LP600 LP650 LP800…etc.
