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254/10nm Laser Filters for Hg laser
254/10nm laser filters is optical filter specially for Hg laser. Coligh manufactures 254-1550nm laser bandpass filters for laser applications.
- Center wavelength 254nm
- FWHM 10nm
- Transmission above 15%
- Blocking depth OD5 for 200-1200nm
254/10nm Laser Filters Description
The 254/10nm laser filter has a central wavelength of 254nm. It uses the principle of multi-layer dielectric film interference and is designed specifically for the 253.7nm ultraviolet spectrum of mercury (Hg) lasers. It allows ultraviolet light near 254nm to pass through, ensuring that the target wavelength transmittance is >15%, with a bandwidth of 10nm (transmission range of approximately 249-259nm). It eliminates interference from other mercury spectral lines (such as 365nm, 404nm, and 435nm) to ensure efficient selection of this wavelength, block other wavelengths, and improve the spectral purity of the laser system.
254/10nm Laser Filters Technical Datasheet
| Parameter | Specification |
| Center Wavelength (CWL) | 254 nm ± 2 nm |
| Bandwidth (FWHM) | 10 nm ± 2 nm |
| Peak Transmission | ≥ 15% |
| Blocking Range | < 0.001% (OD5) from 200 nm to 1200 nm |
| Substrate Material | Fused silica / Optical glass |
| Surface Quality | 80-50， 60-40， 40-20 scratch-dig (per MIL-PRF-13830B) |
| Clear Aperture | > 90% of the diameter |
| Filter Diameter | Customizable (e.g.2.0mm, 12.5 mm, 25 mm, 50 mm) |
| Coating Type | Hard-coated, ion-Assisted coating |
| Angle of Incidence (AOI) | 0° (normal incidence) |
| Durability | MIL-STD-810E, Method 507.3 compliant |
| Tempreture | -40℃- +60℃ |
254/10nm Laser Filter Application
This filter is designed for the 253.7nm ultraviolet spectrum of mercury laser. Its narrow bandpass, high transmittance and strong suppression ability make it a key component for ultraviolet precision control. It is mainly used in the following aspects:
- Ultraviolet sterilization and disinfection system
Mercury lamp or mercury laser is the core light source for water treatment, air purification, and medical device disinfection. It needs to efficiently output 254nm ultraviolet light (the band with the highest sterilization efficiency). The transmittance of 254/10nm laser wavelength is greater than 15%, ensuring the maximum sterilization energy. The out-of-band cutoff depth OD5 completely blocks long-wave ultraviolet light such as 365nm - Fluorescence microscopy
In biomedical research, 254nm ultraviolet light is required to excite specific fluorescent dyes (such as DNA probe DAPI, quantum dot materials). The 254/10nm laser bandpass filter matches the probe absorption peak (such as DAPI absorption peak ~ 260nm), blocks stray light such as 365nm and 435nm, and maximizes the excitation efficiency. - Medical treatment equipment
In the treatment of skin diseases (such as psoriasis and vitiligo), narrow-band ultraviolet light (NB-UVB) targeted treatment is required to avoid the side effects of broad-spectrum ultraviolet light. The narrow-bandpass design of the 254/10nm filter accurately controls the treatment wavelength range, filters out infrared and long-wave ultraviolet light, and reduces the risk of skin burns.
