1.Product Descriptions：
| Characteristics: | 690nm IR Cut-Off Filter |
| Type: | Interference type filter |
| Cut-off Wavelength(in nm): | 690 nm |
| Average Transmittance(%) : | >90% |
| Optical Density (OD): | OD2-OD3 |
| Color: | Light green |
| Surface Quality: | 60/40 scratch-dig |
| Dimension(mm): | Standard for 86x86mm, 80x80mm, other can customized, max. 300x300mm |
| Thickness(mm): | Available: 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: Spectral range:380-1100nm | |
2.Measured Spectral measurement
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Picture 1: IR690nm spectral measurement curve |
3.What is 690nm IR Cut-Off Filter？
A 690nm IR cut-off filter is a type of shortpass filter, Which core function is to efficiently transmit visible light below 690nm while deeply blocking or reflecting near-infrared light above 690nm.
4.What is typical application for 690nm IR Cut-Off Filters?
- Cut-off Wavelength: refers to the designated intermediated wavelength (e.g. 650nm) at transition from transmission to reflective zone, and measure at 50% transmittance.
- Peak or Average Transmittance(in %): typically ≥90%, Higher transmittance might need Anti-reflective(AR) coating.
- Blocking rate: usually in terms of optical density(OD), OD2-OD3 for standard and higher blocking rate 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:
IR650 , 650nm Infrared cut-off Filter, Lens Filter, 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. 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.
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.
