Product Descriptions:
| Characteristics: | 500-650nm & 900-1800nm Dual Bandpass Filter |
| Central Wavelength (CWL): | 500-650nm 900-1800nm dual bandpass |
| Transmittance: | >90% |
| Dimension(in mm): | 80*80mm |
| Thickness(in mm): | 1.0mm |
| Substrate: | Optical Glass |
| Spectral range(in nm): | 380-1800nm |
| Remark： (1) Customized wavelength capability: 380-2500nm, stock for 10nm intervals. (2) Common size for 86x86mm, 80x80mm, other can customized, max. 300x300mm (3) Optional thickness: 0.21、0.3、0.55、0.7、1.0、1.1、2.0、3.0mm…etc (4) Optional substrates: Ultra-clear glass,K9,BK7,B270,D2637T, Quartz Glass(Fused Silica) or other specified. | |
2. Measured Spectral curve example
 |
Picture 1: 500-650nm & 900-1800nm Dual Bandpass Filter spectral measurement. |
What is a Bandpass filter?
A narrow bandpass filters is for transmitting specified wavelength band and block the rest wavelength range.
- By visible and invisible views, there are VIS range, IR and UV bandpass filters.
- By numbers of wavelengths band, there are bandpass filters, dual bandpass, triple bandpass and multi bandpass.
- Typically, for those short range of bandwidth, it’s so called Narrow bandpass filters.
When selecting a Narrow bandpass filters:
- The center wavelength (CWL) will be one of key parameter to be designated, with a tolerance of generally +/-5nm or +/7nm which depend on the user inquiry.
- Secondly, Full Width at Half Maximum(FWHM) means the transmittance range, for those FWHM is short, normally called narrow bandpass filters which no united definition and typically for lower than and equal to 10nm.
- Then, Peak and Average Transmittance, e.g 90%,95%…etc. higher transmittance might need Anti-reflective(AR) coating.
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 Fitlers, IR cut-off Filters, Longpass & Short Filters,Notch Filters, ND filters, Star filters and Optical sapphire block.
