Product Descriptions
| Characteristics: | 730nm Longpass Filter |
| Type: | Interference filter |
| Cut-off Wavelength(CWL): | 730nm ±7nm |
| Average Transmittance(%) : | >92% |
| Optical Density (OD): | OD2 |
| Shape: | Round, Square or customized |
| Color: | Silver |
| Surface Quality: | 60/40 scratch-dig |
| Dimension(mm): | Customized* |
| Thickness(mm): | Customized** |
| Substrate: | Optical Glass *** |
Remark：Spectral range:350-1100nm *Size customized: 86x86mm, 80x80mm, other can customized, max. 300x300mm | |
Measured Spectral curve
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Picture 1: LP730nm Spectral measurement Curve |
What is typical application for 730nm Longpass Filter?
A 730nm longpass filter is an optical interference filter designed to transmit red and near-infrared light at wavelengths longer than 730nm, while effectively blocking shorter-wavelength light below 730nm. The 730nm longpass filters are commonly used in following applications:
- Security and biometric systems – eliminating stray light to boost recognition accuracy.
- Biomedical devices – filtering harmful short-wave light and transmitting near-infrared for effective treatment.
- Fluorescence microscopy and Raman spectroscopy – blocking excitation light to enhance signal-to-noise ratios.
- Industrial machine vision – excluding environmental interference to improve imaging clarity and contrast.
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.
Related products:
760nm Longpass Filter for beauty apparatus,760-1200nm or 760-1800nm Long wavelengths pass, OD2, 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.
