Laser marking filters are mainly used to selectively transmit lasers of specific wavelengths, while blocking stray light, reflected light, and other interfering light to improve marking accuracy, protect equipment components, and ensure the safety of operators. This type of filter needs to have a high damage threshold, high transmittance, and good thermal stability in high-power laser environments.
Main functions and application scenarios:
Wavelength selection and purification
The laser output may contain multiple wavelength components, and the filter can ensure that only the target wavelength (such as 1064nm, 532nm, 355nm, etc.) passes through, improving the beam quality. For example, 1064nm narrowband filters are commonly used in fiber laser marking systems, with a center wavelength accuracy of ± 2nm.
Improve machining accuracy
By eliminating interference from ambient light and non target wavelengths, filters help improve sensor detection accuracy and imaging clarity, thereby optimizing marking positioning and quality control.
Equipment and personnel protection
During the laser marking process, reflected light may cause damage to optical sensors or human eyes. Specific filters can effectively block harmful light radiation and achieve safe operations.
Suitable for multiple types of lasers
Infrared band: 980nm and 1064nm filters are widely used in semiconductor and fiber laser systems.
Green light band: 532nm filter used in conjunction with frequency doubling laser, commonly used in fine marking and microfabrication.
UV band: 365nm narrowband filter is used for UV laser marking and supports high-resolution marking.
Common types and technical characteristics:
Narrowband filter: Only allows a very narrow range of wavelengths to pass through (such as a bandwidth of 30nm), suitable for precise wavelength selection.
Bandpass filter: It can efficiently transmit within a specific wavelength range (such as 1940nm ± 5nm) and is used for special material processing.
Interference type filter: Utilizing multi-layer thin film interference effect to achieve highly selective filtering, suitable for high-precision demand scenarios.
Absorption type filter: It absorbs unwanted wavelengths through the material itself, with a simple structure but weak heat resistance.
